REMOTE MOUNT TWIN TURBO TEST-MEGA LAGGY LS?

[@dr1ver267]

Richard you’re such an OG for this my man😂 taking up the entire dyno room with pipes in the name of science!

[@richardholdener1727]

IT WAS A SERIOUS MESS

[@james10739]

OG means original gangster or old gangster right I disagree I think he is a good guy

[@brandonpanozzo86]

@@james10739 it can mean many things in this case i just think its a way of saying richard is a fucking legand

[@james10739]

Like how bad means good and ill means cool and men can be women and babies are not born with a gender and riots are called peaceful protest or mostly peaceful and unarmed means he had a weapon man I remember when words had meaning that mattered

[@JohnnyAnderson1]

@@james10739 I remember when words (a verbal promise) actually ment something too. And im not even 40 years old yet! My how times have changed quickly..... Crazy to think people used to actually do what they said they would do.... WOW Anyways, Richard is taking all the mystery out of building an awesome power plant. And most of the time he is doing it on my kinda budget!

[@brettcombs774]

I’d love to see thermal coating testing, header wraps, ceramic coatings, turbo blankets. Things like that.

[@joshuagriego1562]

Investigation into the correlation between engine bay heat vs performance/economy would be extremely educational. I personally observed a three point five mile per gallon reduction in gas mileage effeciency on a trip from Albuquerque New Mexico to Flagstaff Arizona recently. On the leg we got the worst mileage, we vapor locked twice, with the fuel evaporation occuring inside the under-hood section of the fuel line, and/or the carburetor.

[@salesteam274]

Those items are generally used to protect other items in your engine bay not to gain power. Great products and I also use them, but only to increase longevity of wiring harnesses and other items that could be compromised from long term heat 👍

[@Entertainment_Enterprise]

@@salesteam274 That's not 100% true if you can maintain the heat inside your headers instead of the heat escaping it'll actually go down the headers you do gain a little bit of horsepower.

[@user-mf2gr3cz6e]

@@Entertainment_Enterprise the general effect will be the same as doing a pull on cold vs hot headers, the more insulated your piping up to the turbo is the better the response will be but horsepower increase is negligible

[@allandriver2066]

@@joshuagriego1562 I certainly think a heavier exhaust tube wall thickness and thermal wrapping would conserve a good amount of thermal energy. 👍

[@KreatorOfDeath1985]

Alternative Channel name, Motor Mythbusters.

[@timearll266]

It would be interesting to test the effect of exhaust tube diameter on lag.

[@iceolation05]

You’d think the smaller the exhaust pipe the faster the volume fills to spin up the turbo

[@carlosmastronardi3296]

my thoughts exactly, sure back pressure might be a concern application depending but would definitely help spool time

[@mrsheetballz]

I think it’s more about energy than volume or speed. Long exhaust means the gasses will cool and loose energy compared to short exhaust.

[@kreflinez9905]

This is totally anecdotal but on my rear mount gt45 5.3 setup going from dual 2.5 inch to a single 2.5 inch heat wrapped increased my spool by 700-800ish rpm. It definitely affects spool and it's especially noticeable in transient driving when rolling into it but it's hard to say how much of that is heat retention vs size and velocity.

[@Hitman-ds1ei]

From some old nascar testing done on primary header tube diameters there was a direct relationship between cylinder volume and exhaust pulse speed in specific diameter correlation, the problem mostly seemed to be too small a diameter primary would create a detrimental subsonic pulse speed and HP would drop off, too large a primary diameter had minimal effect in comparison, assuming from that, pipe diameter used for turbos will have negligible effect other than greater surface area for heat loss, just an observation maybe !

[@stevenkirk2563]

My experience with twin rear mount is higher back pressure ratios than front mounts. Headers work on NA and they work on rear mount turbos, less reversion and it took more timing. Wrap for response. Killer video. Thank you Richard.

[@infinitibossauto]

so wrap an it improve response

[@zapa47]

This one is one of my favorite videos on this channel.

[@patlandymore7035]

Epic!! The best, most informative dyno session I’ve seen yet! Thanks Richard

[@Kj16V]

This is EXACTLY the information I was looking for. Definitely the best rear mount turbo video on KZbin.

[@orangetruckman]

I’m betting that the longer charge piping is allowing for more cooling and that’s why there’s a couple more ponies at the top of the curve. BUT, this is only a guess! Richard is the king of the dyno cell 🤗

[@dennisrobinson8008]

Richard opened my thoughts on remote mount turbos, and it's a viable option! There's alot more space to mount the turbo when we aren't confined to the engine bay. Plus we get the heat out of the engine bay. If oiling is required, a remote reservoir and a electric pump can give the turbo it's own oil supply. Many of the builds I"m seeing mounts the turbo in the place of the muffler. The cars seem plenty muffled.

[@ChinzySpecials]

that's exactly my plan for my reg cab shortbox mud truck. if the engine let's go I don't want metal going through my turbo. or vice versa

[@802Garage]

I assumed the exhaust length would matter more than the charge pipe length for multiple reasons, but I am surprised how little difference the boost path length made. Awesome video!

[@pissedoffpistongarage]

Fancy seeing you here.

[@802Garage]

@@pissedoffpistongarage Well hello kind sir! Nice boosted S-10 Corvair you've got there!

[@pissedoffpistongarage]

@@802Garage shhhhh. No body knows about that yet!😂

[@keithtobin5369]

Just want to say again. Thank you for sharing all your hard work Richard.

[@mygasolineprojects9931]

Another great video, Richard ! Thanks for that ! In a „real live“ remote system, you would wrap the exhaust tubes to keep the heat and energy of the exhaust gas inside all the way up to the turbo. This usually helps a lot to keep them more responsive.

[@mikerounds1907]

Should wrap the exhaust with header wrap to keep the heat in them. I have built a remote turbo both ways.

[@W4RH4WK_W468]

@Richard Holdener you have to be one of the hardest working guys on KZbin. Never short of content or valuable information. I'll keep watching you keep testing.

[@richardholdener1727]

THNX

[@chadwilbur5364]

Agree

[@rodolfogoncalves6189]

Science man! Nothing like a lab and a good scientist to answer all our questions. Thanks for the video.

[@ChadLisonbee]

I’ve been curious about this for a very long time. Awesome video as usual!!

[@malamri424]

deep respect for Mr. Holdener for answering many questions

[@TwoLotus2]

This was settled in the 1980s by the engineering decisions for F1 cars and the better factory turbo motorcycles in the 1980s. 40 years ago. But then people still argue about how airplanes fly, when the math was sorted out in about 1920, or before. 100 years ago.

[@roughwater3454]

I'm exhausted from watching the amount of testing you do. See what I did there? Almost any question I could ever think of you answer for me through testing. Outstanding.

[@richardholdener1727]

THEN THE SYSTEM IS WORKING

[@drbendaroo9610]

Finally. Been looking for some real info on these setups...

[@EricJ411]

When the dyno room gets hot, the bench racing BS stops. Great video. Keep it up!

[@livingintheLight.]

I love all the stuff Richard does, this one was really interesting

[@mbda1]

awesome work Richard! lot's of good comments on how to help some of us that run rear mount on optimizing. This is gold right here, thank you!

[@victorricolucero]

The “why it spoils slower”is because of the law of thermodynamics. I a free with the other guys, I’d like to see the heat wrap, ceramic coating stuff tested. You are Great Richard, TGANKS!

[@johnhazel5385]

Regarding heat loss in the long exaust: What would an insulated long exaust. (header wrap or even a flex pipe over the long exaust tube) Also if a tube was put over the intake tube you could run water beteen the two tubes to create an intercooler.

[@ChurchAutoTest]

Excellent question. When testing remote mount turbos on the chassis dyno making several consecutive runs will result in dramatically improved spool up. I can only attribute this to the exhaust system being much hotter therefore pulling less heat out of the exhaust stream before it reaches the turbo. When you think about it from a physics perspective, this makes sense since the velocity of both the intake and exhaust streams at full throttle are quite high (100-200 ft/s easily - pressure pulses in the streams move even faster). This means that covering the extra distance should only take a tenth of a second or less. This would equate to about 50-100 rpm on the dyno depending on sweep rate. But the rpm to reach full boost is much, much later - on the order of 500-800 rpm. That implies thermal factors.

[@The3chordwonder]

I was thinking the same thing. Header wrap that exhaust pipe. I also wonder if it would improve spool by downsizing the exhaust diameter to keep the gas velocity up. It would probably hurt top end boost, but maybe only when running the highest boost settings. Lastly, I wonder how bad it would be if you put a cat on, e.g. to simulate doing a remote turbo on a late model car. I know the cats pull a lot of temp out, so I know it would be lousy, but the question is "how lousy"?

[@MRMOPARMAN0426]

It depends what you are doing with the engine. For engines under high load for long periods (endurance racing, hauling etc) wrapping the exhaust can create such high exhaust temps that the tube can melt and cave in. This happened to the mod father with his circuit racing holden. Then you have to start looking a either exotic exhaust tube (titainium?) or losing the wrap. For high load for short periods (street/drag etc) its super beneficial to wrap/coat the exhaust as richard mentioned.

[@Donn29]

Keeping heat in will be better, just like any other exhaust setup, but there is still a large surface area to transmit the heat out. There is probably a break even point where a long exhaust with wrap will preform as well as short and no wrap. But I would think that point is not long enough to be called a remote mount. TLDR wrap/coatings will probably make any situation better, but it can only do so much, shorter is better on the exhaust, as shown in the video.

[@NatoriousGamePlay]

What about a ceramic coating? Would that not reduce thermal transfer to the pipe itself providing good benefits

[@davidsabyan2481]

Great comparison, shows how much energy (in the form of heat loss because of the dissipation of the long exhaust pipes) is lost spin the turbo. Have a look at the work that racers have gone to in order to mount the turbos as close as possible to the heat source in recent years. Thank you for the great lesson Richard.

[@5533851]

Awesome work Richard. So far out of any LS configuration, the one I like the most is a big single up front, but low mounted, next to the front pulley or so area. You get weight down low, direct intake fresh air is easy, exhaust dump pipe straight back and low and very short Y pipe/headers. Only down side is a scavenge pump is needed to pull oil.

[@DBSSTEELER]

Going back through your catalog and watching and liking what I missed. Digging the Super Ritchie Fabrication rearmount turbo set up.

[@danbufford8848]

Now you gotta test different diameter exhaust tubing to see tbe change in spool rate. All the old STS kits claimed thdy gest for bigger or smaller tubing to give as much total flow while factoring the speed of the flow.

[@traviswilson3447]

Final conclusion should have also mentioned the importance of keeping heat/energy in the exhaust. My preference would be to run a single 7675 or 7875 with a 2.25 inch single exhaust feed wrapped real good to keep the heat in. Run it on the dyno at like 3k rpms for a few seconds before starting the pull to understand how it would perform on the street or off a trans brake. Great video! Really hope more people will understand that proper rear/remote mount setups don't create a ton of lag. The "it'll take 5 seconds to build boost" and "holy lag!" people are getting annoying. Ha

[@bw3506]

As I was watching I was thinking about the heat loss on hot side. Part of it due to a video of his where he compared turbos he displayed evidence of lower power output/boost on cold startup vs building heat in the system before the pulls.

[@AllAxcess8427]

Very Happy to this Richard! I personally run a remote mount on my car simply cause there was not acquit room for a single under the hood to fit all the hot side and charge tubing, and your results matched mine rather closely on the dyno, very soft below 3k rpm's with expected upper and peak hp numbers. Love all the testing your doing and valuable information your showing. I very much look forward to seeing you test the 3800 v6's soon

[@QPC_LLC]

AYE!! I BEEN PATIENTLY WAITING!! THANKS FOR DOING THIS! Exactly what I expected!

[@keithtobin5369]

Richard. Thank you. You must have been reading my mind. Reporting on this. Thank you for sharing all your hard work

[@rsh7017]

I’d be interested in seeing a video on turbo sizing for remote mount applications. See if you can get response time up with different exhaust diameters and different turbine housing sizes. Figure it might be a cool follow up.

[@srninjastar]

i went from an s480 t6 1.32 at to an s475 t6 1.10 ar. the spool rate was night and day

[@eatonv8747]

@@srninjastar me too but I did it on the 80

[@brianclayton499]

Great test. Before I go bigger later, I am planning to swap mine from front mount to rear, just to play with the differences. Keep up the good work!!

[@yolofullsend]

Wrapping the exhaust in heat wrap greatly improves the response rate in remote mount..

[@frankiethomas1776]

You truly are doing the lords work, thank you for your service!

[@richardholdener1727]

Thank you kindly

[@button-puncher]

Amen to that! Richard Holdener, the Saint of Boost.

[@johnfaubion7720]

You could address the lag like we did in the old days, add a shot of nitrous with a pressure switch to cut the nitrous once the boost came in. Worked best with remote mounted solenoids so that the nitrous faded out as the boost rapidly increased.

[@adamtropin1125]

Thanks Richard I actually asked for this exact test on one of your Q&A sessions. Thanks for getting it done. I'm planning to do bed mount in my project truck so very informative.

[@marcstlaurent3719]

Nice test Richard , I do remember Squire turbos sizing them differently for rear mounts back in the day .

[@nyplantings2420]

Firstly, I have just become a new subscriber and catching up on your content. Good work. I googled rear mount turbos this morning and here you are again! I see the comparative dyno graphs and I eat this stuff up! Would you ever consider plugging these into a drag race simulator to show how a car that makes less low and mid range (or more top end) power will do in the 8th and 1/4 miles? Thanks.

[@LukeSportsman]

Thank you for doing the test I've waited to see and requested back in Feb 2020. Not only specifically for this, BUT as a testing cams.....you can test extremes and then extrapolate the middle from there. THANKS! YOU ROCK

[@DodgyBrothersEngineering]

Great video Richard this is the sort of testing we need to know about. Not everyone want to go the mainstream route, but there is little information out there of what awaits you off the beaten track.

[@fredjones554]

Bro, thanks for the upload. I have always wanted to know these answers. U r a legend

[@docfischer7291]

A friend of mine had worked with these systems on a corvette back in early 2000. I want to say this one was along side Lingenfelter and his system. Ran the system with 2.25” pipes and no change in compression except for replacement cylinder head gaskets. Also twin GT 30’s. You would see a much larger difference. Watch “Nugget Garage “ . Probably an 11.0:1 4.0 1uz doing 1000+Hp. He used 2.25” pipes as well I believe. With the pipes you have there the thermal energy is completely lost .

[@ronnieheath6840]

I think anyway I know how this KZbin stuff goes, anyway happy to just support this channel. Good job man

[@richardholdener1727]

HOW DOES IT GO?

[@ronnieheath6840]

Nobody knows!!!!!!

[@rogergm92]

I learned something huge. Length in exhaust affects but in the intake no. That means that an enormous intercooler is not going to make considerable lag

[@BLKMGK4]

Learned that the hard way myself after being told my small turbo large intercooler wouldn’t work on a 2JZ. I datalogged and debunked that! The tubing has volume but the engine and turbo move massive air and fill that pipe.

[@lucysmith4242]

If anything a bigger IC has less pressure drop and can probably dissipate heat better

[@Shadow0fd3ath24]

it could be a large restriction to air flow though

[@ChurchAutoTest]

In the subaru world going from a relatively inefficient top mount setup to a front mount intercooler typically increases boost onset rpm by 400-600 rpm on the same turbo. We are adding 6 ft of piping though and usually a bigger intercooler core. I doubt the piping makes much difference but the bigger core definitely has an impact. You're trading response for the ability to cool the air much better at higher boost levels.

[@tuloko16]

Is not only the lenght of the exhause. The turbo doesn’t rely 100%on exhaust blowing and spinning the turbine. In fact a vast majority of the force driving the turbine is heat, ie hot expanding gases. On a remote mount you lose a lot of this thermal energy. There are ways to regain some of that thermal energy. Back in the day we experimented with adding cats before the remote mout turbo. And there were noticeable gains. But who would chance it with a chunk of cat making it to the turbine. Another way some of that thermal energy can be re gained is by retarding timing. But its harder on the exhaust valves and you lose power by giving up timing. Now the most extreme way i have seen this done was adding an injector and a coil and plug near the turbo(think mexican low rider flame trowers) this method actually produced better results then turbo front mounted. But it was problematic. We teied this on the 90’s, so we didn’t really had a way to control what was going on with the injector by the turbo. It was either on or off. So lets say we had “issues” with the flame traveling back into the exhaust and exploding the pipes, so we aborted that. With todays available controllers, this may be wort a re-visit.

[@derrick_v]

Wow, you do everything! Thanks

[@richardholdener1727]

I try

[@mrb.5610]

Can't argue with the numbers ! Good video !!

[@sickTSI]

The STS remote kit on my 6.4 Hemi is quite responsive and spools really quick.

[@god1st.530]

An army buddy of mines had the 1st remote rear mounted turbo on a 98 trans am ls car. An even bk then he was hard to beat. I'm still a nos guy. But thanks for all the info on turbos. Helps alot on me knowing exactly what to do. Gm ls lt FTW

[@xoxo9623]

I guess rear mount need more time to build pressure on the long pipe to the intake, smaller pipe size will help?

[@richardholdener1727]

it's not the intake tube length-it's the exhaust length and temp

[@xoxo9623]

​@@richardholdener1727ah I see, I hear that wrapping the exhaust pipe can help to keep the gas temp?

[@sons_of_slewfoot_garage]

I built my s10 how it is because of this video. Lm7, gapped rings, tbss, summit 8710r1 cam, flowtech stainless 1 7/8 longtubes heat wrapped, deka 80s, 2 380 pumps, water to air, twin gt3582 turbos in the bed. 3 in collector to 2.5 stainless exhaust pipe wrapped, 2 44mm gates, turbosmart gen 2 50mm bov. Cant wait to rip in it. Im going to 30psi though in e85!

[@richardholdener1727]

start at lower boost then work your way up

[@sons_of_slewfoot_garage]

Oh for sure, but for the truck to trap what I want it to at the weight it's at, my math says 25psi or more. Haven't done as many as you, but this isn't my first turbo rig. Have an 81 c10 with a 416, billet wheel s488 and a csu blowthrough as well. Good advice though, but I'm throwing the kitchen sink and the dirty dishes at it! Lol

[@button-puncher]

YES! THANK YOU!!! I've always wanted someone to do this. Just like your previous video, it's all about the heat. Like others have said, I'd love to see header wrap and maybe even rock wool pipe insulation, and also 0.5" smaller pipe and a reduced AR ratio turbine housing. Check out MinWool-1200 Pipe Insulation. Also, I think the majority doing remote mount will have a single turbo setup (like a GT4508R aka GT45R). I'd also be interesting to use a small 25 or 50 shot of nitrous to help spool. Use a progressive controller to have the nitrous run below 4.5-5k. 20lb bottle would last quite a while.

[@ts302]

Great work Richard! With a little ingenuity, I sure most of the cons of running a remote setup could be minimized. A remote turbo(s) mount would be ideal for a drag application (spooling the turbos on a trans brake)-less underhood temps, weight distribution.....

[@HurricaneLantern]

Love the video Would love a follow up video attempting to mitigate the dowsides Maybe using a ceramic header or even a fully wrapped exhaust And a smaller turbo Id also like to see if the intercooler placement makes on the lag (next to turbo in the rear, or near the intake at the front

[@scotttod6954]

Back to back 90s is like adding 15 feet of pipe. So I heard in HVAC school.

[@richardholdener1727]

that seems excessive

[@scotttod6954]

@@richardholdener1727 How tight the bend matters a lot. www.thermopedia.com/content/577/ . I know 15 feet seems like a lot but 15 feet of straight pipe really does not have that much restriction. Your first 90 will be the same restriction as 9 feet of pipe.

[@lucysmith4242]

Yeah K factors and equivalent head losses for different geometries/fittings. This is interesting however, I believe what you are talking about is in steady state analysis

[@orangetruckman]

In a car I have no doubt that there would be a many tighter twist and turns to make it fit remotely.

[@calvinmathers]

Were you measuring intake temps? I would think the long intake would help with cooling a tiny bit. Not enough to purposely do it but to make sense of the tiny bit more peak power.

[@eatonv8747]

Lot of great ideas to test in here in the comments Richard. You played with the cold side ( the easy side) now can you play with the hot . It would be interesting to see the power graph shapes between cast, shorty's and long tube. I know from real world testing in the spool time differences but the effect and top end power figures I cannot give as we were road tuning it. It is a constant internet conversation piece can you put it to bed.

[@timwhiting6854]

Looks like you combined a LS with a Trombone!

[@boostedgringo5885]

Thanks once again for doing all these crazy combos. I’ve said it for years they the intake tract doesn’t get effected n welt as much as exhaust. My current combo is a 2.0 with a remote mounted gt30r and I can certainly tell a lag in comparison. It’s only temporary, so I’m not worried about it. Thanks again

[@Bigchief45]

Should see if decreasing pipe size increases response. Or increasing size changes it.

[@capefisher2857]

Great video Richard. Be great if you showed how to maximise rear mount turbo performance, by showing the benefits of wrapping exhaust, selecting smaller turbo AR, advantages of smaller hot side pipes etc.

[@Pointless-fishing-adventures]

Ok great video. Maybe the first test with the turbo mounted in what would be in the engine bay you could have tested a long dump off the back of the turbo to simulate an exhaust seeing we are looking at more stock appearing setups.

[@surreaLinnovatioN]

Really insightful, thank you I'm interested in seeing a big single in remote mount and Snuffy also

[@totensiebush]

I'd really love to see this done using longtube headers for the remote mount. I wonder how much of the extra length they'd make up for.

[@bluecollarfox913]

What an awesome test. I’m thinking about remote mounting a turbo on my F-Body LT-1 Camaro. This should work great.

[@Shadow0fd3ath24]

I swear its like people dont realize just how fast that air is moving and that its COSNATSNTLY moving and that the lag is pretty well unnoticeable to most people with a 3500+ stall on a v8 since it doesnt engage fully till the converter is working fully

[@gofastwclass]

That's only because you're waiting on the 3500 RPM stall to spool on the street.

[@Shadow0fd3ath24]

@@gofastwclass exactly my point. So the lag to the turbos is imperceptible

[@otm646]

@@Shadow0fd3ath24 You're missing his point. Few people are running a converter that loose on the street. Off the line the turbo lag would be immense on a streetable converter.

[@Petrol360]

So what I learned was turbo=good. Haha great to see the video actually testing this! From my prospective it opens up some good options. Front mounted turbos can be a bit harder for packing compared to front mount. If you are of with the lag and response its a great option. Besides boost is always better no matter where you put it!

[@MilanoGuyTexas]

Hey that was great, real data, as opposed to speculation. Very good to note that the engine seems largely insensitive to the length of the intercooler piping. I t would be interesting to know if on the remote mounted turbo if you could get some of that lost torque back, by wrapping the exhaust pipes, using stainless pipe, having less U-turns in the system and so on. Keep up the good work.

[@LacticPK]

Would be interesting to test the cooling effect of a longer intake tubing on non intercooled applications

[@QPC_LLC]

Negligible. There's just not enough surface area x time.

[@Plainjuicebox]

Would love to see this test again with updated cam selections.

[@richardholdener1727]

updated to what?

[@johnparrish9215]

Mr. Holdener, a question. We know that a certain amount of exhaust pressure is needed to drive the turbo and that amount varies for each combination. However, is it possible to use a second wastegate to regulate excessive back pressure without interfering with the function of the primary wastegate's boost controlling duties? The engine test that comes to mind was the GT45 single on the 454. It had massive backpressure at low boost but an excellent response. If the engine could have seen the same boost but with half the backpressure it would have been acceptable for street use.

[@tommylyeah]

Sounds like a cool idea.

[@fascistpedant758]

If you dump back pressure you'll lower boost. That's how the waste gate works. Unless the turbo is already choking.

[@yolofullsend]

I'd guess that if the turbo is sized correctly then the backpressure won't be an issue... If you're trying to use a small turbo for response in a max effort build then it may help some but youre still going to be overspinning the lil guy and creating lots of heat.

[@johnparrish9215]

@@yolofullsend I was thinking LOW boost truck engine. Off idle boost would be great for that engine.

[@johnparrish9215]

@@fascistpedant758 But what if you regulate the maximum exhaust pressure at 5 psi more than the turbo needs? The first wastegate would be set for what boost you want, say 7 pounds, but the second turbo is set at a level the turbo will never need to provide that boost it would just shed excessive pressure. Follow what I'm saying???

[@Adrianzx]

I have experience with this kind of stuff and have a pretty good idea of what's going to happen but I'm still going to enjoy every moment of verifying

[@maurymoynihan5245]

Great Job Richard! Would b interesting to see charge pipe diameter changes/IC/nonIC/length and IAT's. Thx agian!

[@Dr_Xyzt]

I bet you could feel the heat from all that turbo piping. Kudos for doing that work!

[@Erichhh]

The exhaust side likes preservation of pulse energy, the intake side likes the elimination of pulse energy. The longer tubing (larger diameter is similar) acts like a capacitor to smooth out pulse energy.

[@wildnfree223]

dissipation vs inhalation lol ?

[@johnroberts9311]

Richard THANK YOU for this video. Long time watcher, first time poster. I am designing a remote mount turbo system right now for a 5.7L LS1 and was agonizing over response time based on some of the various widespread comments on the ugly side of remote mount turbos. After watching this, I am not as concerned about it. Splitting the test into intake vs exhaust effects, as well as twin vs single turbos was also very helpful. I'll definitely be going with a single turbo, probably a T4 76mm size since my power gain goals are modest (and will stay that way). Questions: - I would expect a wrapped (insulated) exhaust between the engine and the turbine to help with spool. Is this something you have tested (or seen tested)? - With E85 as the fuel, I would expect some of the spool lag to be offset by the increased exhaust gas flow vs. the same setup with E10 (pump gas). I saw this when, using the same turbo setup on the same motor, the spool was MUCH faster when the fuel was switched to E85. I would expect the same to be true here. Do you agree?

[@Aladinscave]

On the salt flats remote mounting the turbos can be like traction control because the boost hit is way smoother as the exhaust volume acts like a cushion building pressure before boost

[@daveyorke3818]

Yes finally, back to the BUICK!!!!!

[@jonathansalgado9194]

Can we get another test with header wrap? And maybe figure out a way to optimize the rear mount set up. Thanks!

[@projectinlinesix]

Factual evidence from recorded testing! I love it.

[@punker6506]

Test effect of exhaust wrap on lag in remote mounts. Always heard wrap helps them spool faster

[@Dynodon64]

I like to gradual power output of the remote mount turbos better. They climb like a centrifugal blower. Nice gradual power increase with rpm. Less concern with timing advance as boost comes in more steady. Also gives the tires more time to hook up without the higher low torque from the closer mount turbos. It's a better output curve all the way to max RPM.

[@keithtobin5369]

😊 next we need to compare cast-iron exhaust manifolds to headers. On a turbo setup and see what the end result would be? The reason I ask is because. A turbo puts a restriction in the exhaust and headers are made to help scavenge the overlap area.

[@thetransformatorium7980]

This guy has my dream job! Awesome as always Richard! Cheers! 😁

[@Mikeoxhard24_7]

should test with heat wrap to see how keeping the heat in exhaust affects reponse, or some cheaper alternative to heat wrap

[@coalstang]

awesome test. thank you.

[@richardholdener1727]

You're welcome!

[@383mazda]

You've got to remember, a street car has the same amount of exhaust whether the turbo is under ther hood or remote mount. Your first test should have that 12ft of exhaust pipe bolted on after the turbo (which would also hinder low end response).

[@BoyRacer141]

If the post turbo pipe work is sized appropriately to not reduce the pressure difference across the turbine then the length of that pipe should have little impact to low end response. I don’t think there is such thing as too big for post turbo pipe diameter. Having said that, it would be challenging to fit the correct size full system behind a big single turbo V8 particularly in a tight engine bay.

[@srninjastar]

@@BoyRacer141 the diameter of the pipe feeding the turbo doesn’t really matter. it’s the diameter of the dow pipe that does. lots of power can be gain from going to a 3” dp to a 4” and so on. the faster the exhaust can be expelled the more power it will make.

[@Dr_Xyzt]

Fabbing that up in the dyno room is awkward enough....

[@turbotunna3794]

Richard - thank you for doing this comparison! Great video man. It makes sense that us remote mount turbo guys drop a size in the turbine housing (A/R) when rear mounting. I'd be really interested in seeing a similar comparison with that change in turbine A/R implemented using the same turbos.

[@richardholdener1727]

NEEDS SMALLER TUBING, SHORTER AND CHANGE IN AR

[@abz520]

You're doing GOD'S work. You need your own show.

[@Z28David]

Have you considered running this test but with a single? I'd say its rather rare for a twin remote setup unless it's for a corvette or gto. I believe single remote setups are more common. Perhaps recreate and see what the effect longtubes have on response rate? Also do you think there would've been a difference if you had increased the length of pipe from the turbo to the intercooler instead of the intercooler to the throttlebody?

[@supernova5end]

Nice work. I wonder if the response time could be offset by coating the pipes or wrapping them. So glad you did this because this can give people more options for turbo'ing their cars and what they can expect or modify for.

[@leftcoastdrifter]

great video. i've been toying around with remote mounting a turbo on my pick up.

[@escuelaviejafarms]

Oh yeah, definitely smaller turbos and decrease the exhaust diameter. I would love to see what happens.

[@Hydrazine1000]

Richard, YOU LEFT THE CAPS LOCK ON! Really, I'll happily listen to you dispensing knowledge, you have my attention without shouting too. Can you run the dyno in locked RPM mode? Is that a thing that is possible? It would be interesting to see what happens locked at 5000 rpm. Measure how long it takes to get to max. torque by jumping from, say, 10% throttle to wide open while the engine brake maintains 5000 rpm. This should be able to give you an idea of dynamic response of remote vs close turbo location.

[@dadsgarage420]

What’s our back pressure saying about all this

[@richardholdener1727]

YES

[@madmod]

This could be the reason sts kits get away with relatively smaller turbochargers.

[@Xxcody3232xX]

@@madmod always running into you lol

[@madmod]

@@Xxcody3232xX hell yeah! Hey i just ordered a victor jr manifold and was thinking about your vid!

[@Xxcody3232xX]

@@madmod that's awesome. Try it out. Haven't got the truck going yet. Need to surface the heads. No compression in every cylinder good timing and valves

[@tommylyeah]

John's already in here... AND he already blamed squirrels.😂

[@christopherc3017]

Thank you for the info. I am in the process of setting something similar to this.

[@AAELMIGER]

I would like to see this setup with compounding turbos, small turbo close to the motor, big turbo 12-ft away that would fix your lag issue maybe???. Awesome video keep up the good work 👍👍🍻

[@ryancrisp6786]

Interested but practically, you'd never run it that way. If you went though the effort of mounting them underhood you'd never compound in the engine bay. But still, I'm interested to see the result!