Gen V LT Direct Injection Horsepower Secret: Tech Tip Tuesday

[@zdub4124]

Keep the LT stuff coming. More people need education and tips for them. Thg thanks guys!

[@pra3t0rian]

Just the tip.

[@1kGarandGuy]

facts , we need all the info we can get on these things

[@lukedoehrman2304]

Fun fact, when I was a process engineering intern I worked with this fuel line and there is actually a check valve inside the flex joint. GM wanted to prevent the high pressure pump from loosing fuel before starting. If I ever get an lt4 this will be the first thing I remove.

[@trey8543]

Do you see any harm in using the checkless line with a checkless fuel pump? This will be a max effort race application on a gen v LT1 using the LT4 pump and injectors. Plan to convert the in-tank lift pump to a walbro 535- which has no built in check.

[@lukedoehrman2304]

@@trey8543 might take longer to crank after sitting.

[@MoonBoost]

@@lukedoehrman2304 this, my C7Z mostly takes longer to start now once it’s been driven and warm. Cranks a little bit and slowly fires. No big deal.

[@Deetroitmuscle]

I always thought the check valve was the large drum looking part before the rails. Makes that ticking sound that makes all the Boomers bring in their vettes to service thinking they have a bad lifter....🤣

[@groomlake51]

🤦‍♂️ where do you work now?

[@That_Corvette_Guy]

Thank you for looking out for us LT guys 👍. Excited to see what else you come up with.

[@chuck1607]

Great video, thank you. Your explanation was simple and straight forward. I'm doing a swap and was curious about how to convert from push-on fitting to AN. Perfect!!! I just bought 2 from your website.

[@mrmchaffey]

I have a l86 and a 72 nova so I appreciate all your videos, keep them coming

[@iVitalzHD]

Itd be pretty cool if you guys did more gen V tech tips. I don’t have one but I want to learn! I feel like you guys do a great job at explaining things so there easy to understand.

[@MWR-lg9qp]

Sure wish I had seen this 5 years ago. Great advice guys.

[@jayvog1601]

Would like to see a video updating us on your Nova, after what happen on your way up race week. Never heard any details on what actually happened..

[@JWP1990]

Same!

[@christopherselepec247]

Great tech tip. Will order parts tomorrow. Building a Gen V 427 for my truck now! Keep it coming on the GEN V stuff. Curios how you did your catch can on the Nova. Left a message for you guys and have not heard back.

[@MotionRaceworksOfficial]

Jay Vog should be going back together in the next few weeks. We will work that into the channel!

[@jayvog1601]

I just really was amazed when I first saw that combination, on top of that body style Nova has always been my favorite. The first I remember, my father (RIP), had a 1971 that I have always wanted to build one in rememberance of him, hopefully one of these days.

[@mrmchaffey]

I will be buying my fittings from you guys to help support your R&D thanks for all your efforts

[@MotionRaceworksOfficial]

Thank you!

[@matrox]

@@MotionRaceworksOfficial Mine is a 17 SS Camaro 6spd. How much more HP will I gain?

[@saudi75]

can you show what the finished line looks like after you do this upgrade ?

[@charleswayne8595]

Did we get it finished

[@bowlofduck]

Awesome video, I just subscribed. Would love to see more on beefing up an L83, both expensive and inexpensive options.

[@hanssgarage1886]

Tech Tip Tuesday is my new favourite! Good job!

[@MountainMcCumbee]

I wish this would be offered as a kit. I’m going to de doing a cam swap on my L83 and just ordering 1 kit would be great and not having to search different fittings. Have you guys thought about or tried anything on the injector side of the pump? There’s restrictions inside that tubing as well but with the high pressure maybe a bigger I.D. stainless solid line that could match diameter of the pre pump side hose and fittings.

[@thehpw]

Love the gen 5 videos. Going to swap into my 68 Camaro

[@aaronmindrup9587]

can you show what the finished line looks like after you do this upgrade ? pretty please

[@scotmiller8379]

More LT content! Gonna be swapping a L83 into my BMW 1 series track car.

[@jeredtapp5760]

More Gen V!! Pretty please.

[@anthonybomicino3276]

Do you offer a flex line replacement with the fittings for a direct swap on LT1/6th gen Camaro?

[@jdray6834]

I would like to cover fuel flow threw the low side and high side of the lt motors. Along with covering mechanical pump spacer and when is it needed

[@MotionRaceworksOfficial]

We have not found a need for a mechanical pump spacer yet.

[@Jommybutler1234]

JD Reynolds Are you referring to a lash cap?

[@Jommybutler1234]

Motion Raceworks Official Are you referring to a lash cap?

[@RAWRMotorsports]

Got my first LT in the shop for teardown now L83 2015 1500 truck with afm problems .. getting stage 2 cam and all supporting mods

[@emanueltucker1561]

Which cam and supporting items you running did you op for the trunion

[@oneounceslugAPEX]

Is there a more in-depth video on this

[@paulpasternak2026]

Like the tip. Lt to 91 c1500 planed. Please more!

[@rubenvor]

Great info! Thanks for sharing. Who does stand alone flashing for the PCM and TCM on these engines?

[@booostin21psi]

Do you guys have any videos on engine builds of the GenV? Also, I have a Tahoe with an L83 that I’m building an L86 for.. anything I should be aware of? Can you use the same computer and just tune it for the L86?

[@ericmclaughlin4459]

Great tip! I am working on a gen V swap for my JK and was looking at using a stroker gen V but I can't seem to find torque numbers below like 3500 rpm. Not looking to build a dragster but would love to have stump pulling torque.

[@bigbrown2690]

So does MRW sell a bigger line to use between the two fittings? Or do we just supply our own that we find? Maybe it’s not as easy to make but I think it’d be great for MRW to sell a whole “LT1/LT4” Fuel line upgrade kit that came with the two fittings and the bigger line to connect the two in a stock location.

[@anthonypapa8676]

what about the check valve in the line

[@charleswayne8595]

So do I need to take the cam pump out?😊

[@markhoward3851]

Is this the same thing on the new L8T? What are options to use that with an aftermarket EFI system for an LS swap?

[@Very_Angry_Citizen]

GrubWorm seems to have LT's dialed in. He made LT motors great again.

[@Maplefed]

Different LT

[@Tdot21]

Cool 😎. Thanks for the tip.

[@MarkHyle-fw9lr]

I have a 2023 zl1. I'm doing a complete cam pkg, dod/after delete, headers. Would you recommend changing the fuel lines to your system?

[@Techangler65]

Yes looking for a shop to do a cam swap on my 2015 Silverado L86 Any thoughts?

[@Sixtupletslived]

L8T content would be awesome

[@jasonnellis3566]

i have 2014 silverado ill do this when do LT2 swap. will this work for my truck as well

[@joeyjojojr.shabadoo915]

DOUG, you had mentioned before that Holley was a bit finicky with DI control, but now that it has been out for long enough, I would imagine the issues are sorted out. I would really like to know if it's possible to run a Dual Fuel setup on an LT1, where as pump gas runs through the DI system, then Methanol can be PORT injected via 8 injectors at high boost levels similar to how guys are doing Dual Fuel LS Drag/Drive setups right now. It's just such a shame that many guys are running LT setups, but have ditched the DI setups for pure port injection at higher HP levels when a Dual Fuel DI/Port combo would be so sweet if it could be controlled like on an LS.

[@Jommybutler1234]

How did you test this “Black Magic” to confirm that the changes resulted in additional fuel delivery thru the injector?

[@MotionRaceworksOfficial]

Engines not making the hp they should and then making the hp they should after changing it.

[@Jommybutler1234]

Motion Raceworks Official I wish you would have elaborated on that in the video and showed your work on the dyno. It would have been interesting. Without a correlation between the effort and the results, it falls flat. There is still a great deal of mystery surrounding DI and no one in the industry seems willing to put in the work to give definitive answers on a system that has been put for over five years. There isn’t even an online calculator that works for DI. People are forced to throw things at the problem, without knowing what actually worked. You have an opportunity to make a great video, that should get lots of views with the correct title. “How to gain 25 horsepower for $25”. I know there are loads of variables, but the basic questions are still unanswered, except with anecdotal evidence on the Forums: - How far can you go with the stock Gen V LT1 fuel system? - Does a +38% Cam Fuel Lobe actually deliver 38% more Fuel to the cylinder - Which component is first to have an impact and should be addressed first. Low side, HPFP, Injectors, Plumbing - If you upgrade the Plumbing, how much does that raise the cap on HP? - How much further will upgrading to the LT4 HPFP get you? - At what HP does the low side pump need to be upgraded? - At what power level do the stock injectors become the limitation? No one seems to have any real answers, they just want to sell a package upgrade Just my simple thoughts. Hopefully, you will produce the video. Thanks, Kyle

[@Jommybutler1234]

Motion Raceworks Official Publication of information like this from vendors, further muddies the water: www.lsxmag.com/tech-stories/engine/lingenfelter-kit-delivers-serious-fuel-flow-capability-lt-motors/ Using the assertions in the article, the Lingenfelter Big Bore pump delivers 30% more fuel to the injector than an LT1 HPFP and will support 1,100 hp in a turbo or SC applications. If this is the case, shouldn’t a +38% fuel lobe paired w the LT1 HPFP support 1,100 hp?

[@TheRdub82]

@@Jommybutler1234 Is 100% correct; this video needs more context and data and could have been more in depth. After watching this video I had even more questions. There's no such thing as the easy button, if you wan to give the performance customer some confidence; make sure you give as much pertinent information as possible.

[@sc_mastertech8641]

I find this topic very interesting. I am a dealership tech and work on Corvettes at the dealership level. I have actually replaced that little line to fix a surprisingly loud rattle noise under accel. According to GM there is a check valve in it to isolate the high pressure pump from making noise or transmitting that noise. Certainly I can see that line being a restriction and understand your position of using AN line instead, but I’m curious if this transmits any noticeable noise. Next time I get my hands on one I can cut up I intend on doing so because GM saying there’s a valve in it doesn’t make much sense, maybe something to dampen but I don’t know. Curious on your thoughts if you have any.

[@MotionRaceworksOfficial]

Scott Cordell to be quite honest we have only done this on race applications and they’re loud already so probably wouldn’t notice it. Def keep us posted!

[@D2O2]

Haven't cut one open either, but I suspect there is something in the hose section being held in place via the pinch clamp on the outside, otherwise what is the clamp for?

[@erikbrown2682]

Do u guys do cams there

[@jeffglover262]

i bought a 2016 model 6.2 out of a denali thats got a ton of aftermarket parts, cam, ls7 lifters, pushrods, a lot of goodies, dod delete, vvt delete, etc etc, i bought it to go in my 09 G8 Gt to replace the 6.0, my question it can i do away with this high pressure fuel pump headache and just use my 6.0 heads and fuel system and will this motor run?

[@thephantomzoneboxing]

yes wanna know how?

[@ShawnTyree-x9u]

I'm working on a 2021 gen v swap going into a k5 blazer. It has the 10 speed transmission with it . The ecm is the e90, how or where do I go to get the ecm unlocked and tuned?

[@jgonzalez6250]

Great info 👍🏼

[@509camaro9]

Ordering now thanks men

[@mfrfpv9079]

If the high pressure pump goes out does it destroy the fuel injectors?

[@optimusprime2015m7]

Do you think it needs a check valve in there somewhere to keep pressure on the high side pump? I saw that lingenfelter offers one for around $200 but is it necessary?

[@That_Diesel_Guy]

Doesn’t the factory fuel line have a check valve in it? Without it wouldn’t it be possible to bleed back fuel and cause the hpfp to start up dry?

[@robbygray9562]

No the line doesnt, the check valve is in the pump assembly thats in the tank

[@Standyourground21]

I really wish you would show the finished project with the hose hooked up. My brain is just not seeing it, I get what you are saying but I am the type that needs to see the finished project then the light goes on in my brain.

[@garymathews4042]

I believe there is a check ball in that section of the fuel line ,so swap out the stock GM fuel line .

[@leenorton2406]

What is the height from the valley on the block to the top of the supercharger?

[@chrisford9637]

What brand of harness are you guys using for the gen v engine

[@groomlake51]

My question is if you increase the fuel supply lines diameter from lift pump to the injection pump. You get more volume @ lower pressures. Cavitation occurs in a fluid aka positive pressure hydraulic pump. When the outlet pressure diverges too far from the pumps inlet pressure. In theory your trick is ass backwards. The restriction are there in the oem fuel line must be there to keep fuel pressure high with reduced volume due to different engine displacement and or power out puts. To combat cavitation due to using the same size injection pump on multiple engine displacements with different power out put demands!!! I know nothing about modern Oem LT stuff. I’m guessing and hoping that line is a supply line from the “Lift” pump to “injection” pump and only sees 40-50 psi if your Recommending switching from a hard line to soft hose. Help me understand how a pressurized line at even lower pressures can collapse? Increasing inlet fuel (volume) to a injection pump from a lift pump could only effect injection pump output in a incorrectly engineered system. I can’t see GM spending 6 million hours engineering the system and missing that. I’m assuming what you are talking about is cavitation. Witch is what happens when hydraulic pumps inlet pressure and outlet pressure divergent pressures become to great. It’s the reason a Bosch CP3 diesel injection pump houses 3 individual pumps to step the 20 psi @ the inlet from the lift pump to 30,000 psi to the injector so that it can over come cylinder pressures and spray fuel into the combustion chambers. I read the modern LT platform injection pump supply’s 2,000 psi to the injector witch fires much earlier in the compression stroke at reduced cylinder pressure when compared.

[@lorider4693]

Ok so what about the cp3 with no lift pump?? Id say thats a serious difference in inlet/outlet pressure???

[@josemartin5871]

i ordered a lt4 mechanical fuel pump and lt4 injectors for a buddy of mine that is doing an 6.2 swap on a single cab 2019 silverado that had the original l83 in it with cam and magnuson supercharger. the 6.2 is getting cam and supercharger thrown on it in your opinion will it need that fuel line delete? We are just looking to make basically lt4 power around 500 to 600 at the wheels. currently made 420 hp with the 5.3 and supercharger

[@johnnieburge4997]

This was a great video! I’m doing a LT4 to an LT5 swap. I need part #12665549 & #12665159. But I can’t find the LT5 multi port fuel rails for supercharger. How can I make my own fuel rails, any suggestions?

[@wadebond7679]

What do you mean by tuning.

[@n5yiz]

Wait until you see the size of the inlet bore on the pump itself.

[@Jommybutler1234]

I wondered that as well and asked if they did any flow testing. The answer was “No” Seems that the smallest passage will always be the limiting factor. Pumping non-compressible fuel from a small tube into a larger tune and back into a smaller tube, should not change the volume or pressure at the injector. Physics calls it conservation of energy. I’m not positive, but, I think that’s how it works

[@liambauer7922]

hey bro im tryna lt swap my brz any big warnings before i jump off the deep end and buy the engine

[@TheMrmmkkpro]

I have a somewhat mundane question. I own a 2015 silverado L86, lifters #4 & #7 collapsed, so im tearing her down to repair. Do you guys know how to get the oil dipstick tube out? I can spin it to a point but can't get it out. I have pulled, twisted, but no luck. I'm afraid it will break if I pull to hard. I need it out of the way so I can push exhaust back and get to bottom head bolts. Cool tip on that fuel line, now would be a good time for me to try that mod, thanks. 👍👍🏁🏁

[@lorider4693]

Mine just pulled out the same as an ls..... spin it back to where it was and pull hard come easy is what I always say. Hope this helps

[@alexmosurak2773]

How would I go about putting a 4L80 on it? Bolt pattern is different?

[@philwatson9288]

What about the fuel lines from the pump to the injectors. Do you have an aftermarket solution for them?

[@Jommybutler1234]

Phil Watson The lines he is discussing connect the High Pressure Fuel Pump to the Fuel Rails, which comment to the Injectors There is no fuel line that connects the HPFP directly to the Injectors

[@philwatson9288]

@@Jommybutler1234 I understand which lines he is discussing. I am asking about the lines to the fuel rail...you know the ones that aren't reusable from GM?

[@Jommybutler1234]

Phil Watson I have not heard of the High Pressure Rail Crossover Fuel Line being considered a restriction in the system. Can you provide some addl info ?

[@philwatson9288]

@@Jommybutler1234 where did I say it's a restriction? I am looking for an alternative to the GM lines that aren't reusable.

[@Jommybutler1234]

Phil Watson Relax The focus of the video was removing restrictions within the fuel delivery system, so I thought that’s what your question was related to. Swapping to quality AN fittings is most $ than the OEM parts. How often are you disassembling your HPF system?

[@knjpollard]

I just added an E85 kit to my LT4 Z06, will this help me run more than E50 mix?

[@jerrychase4177]

How do you keep the intake valves clean?

[@MotionRaceworksOfficial]

With port injection

[@ddn79]

So...when is the Gen 6 Camaro ever going to be finished or go down the track?

[@MotionRaceworksOfficial]

Jeremy at Fasterproms and his crew have it currently. We had some strange issues with cam and crank signals. They diagnosed and fixed it. Currently tuning on it as we speak. Should be hitting the track very soon!

[@kjellarnelver5364]

Do a story on the venting system

[@reamsfabrication5215]

So with the 5.3 and 6.2 is there a difference in diameter of the feed and high pressure lines to the high pressure pump. Currently building a 5.3 rear mounted turbo in a 16 Silverado and going to a 525 low side in a factory housing. Curious what power I can make without swapping injectors and hpfp

[@trey8543]

Howd it go swapping low side only? Did you end up going LT4 high side? I have a LT4 blower ported by Katech waiting to go on my 5.3, my goal is to push 10psi+ on straight E85. I have the LT4 pump and injectors, plan to go with the walbro 535 pump for low side and going to do the upgrade in this video. I’m trying to find someone that knows if this setup would support straight e85 @ 10-12lbs. There’s a guy on here with the 525 walbro and stock high side the and he’s out of fuel with E60 blend and 6-7psi making around 485whp I believe.

[@rongosick4546]

@@trey8543 I'm thinking 2 525s in tank with 10an feed out of the tank to a good high pressure efi fuel regulator with the lt4 injectors and mechanical pump on e85 should support 1400 hp I'm thinking. I'm thinking of going 6.6 gen5 so I'm here for information about the DI before I pull the gun on the swap

[@reamsfabrication5215]

@@trey8543 I went 535 and lt4 injectors and ran out with stock hpfp at e62. Waiting to either shim stock or go to lt4. I made 580 on 62% e

[@trey8543]

@@reamsfabrication5215 Nice, how much boost? I still haven’t started my build, I’m trying to settle on a cam still and there have been some essential GM parts out of stock for awhile now (head gaskets etc). I’m looking at the cam motion PD 220/236 w/+38% fuel lobe. I have the walbro 535, lt4 hpfp & injectors, and the LT5 fuel feed line for the hpfp w/ no check valve. Goal is to hit 600+whp and be able to run full e85.

[@reamsfabrication5215]

@@trey8543 I’d suggest a Brian tooley specd camshaft for boost with 38% lobe. I’m running 10.5-11.2 roughly and my tune is conservative as I don’t want to blow the ring lands. I’m looking for a new block now to just install new rings and tap to .028 for boost. Swap cam for a non vvt/dod delete but stock specs as I want to break the sbe record with no changes to specs internally

[@Van_LifeCardz]

You are a VIP 🎉🎉

[@davidperez6493]

Ty useful tip 👍

[@JuanHernandez-qg6mp]

Hello u have the part numbers

[@jameshesler7850]

I have 4.3l V6 version I would like to fuel line upgrade

[@cramstick]

There is a check valve in it too.

[@DjSubstain]

What's going on with the Nova?

[@J2A61]

Cool I need this

[@Van_LifeCardz]

Please do more LT engines everyone is a professional hacker at LS because its so easy the hard one is LT

[@amasterson1490]

What's a good header for the gen 5?

[@MountainMcCumbee]

Kooks

[@Gurdil95]

Wouldn't AN lines burst due to extreme pressures from DI ?

[@MotionRaceworksOfficial]

The extreme pressures are only after the high pressure fuel pump, this is before

[@ChickenwithaHelmet]

This may sound like a stupid idea, but since these engines are direct injection, and some hotrod guys prefer mechanical injection over electronic injection (me being one of those guys), why not fit a properly built Bosch MW8 injection pump on it? The end result: a Direct Injection P-Pumped LT engine.

[@ChickenwithaHelmet]

@@bryangreenleaf1946 Thanks! The idea came up one day when I was researching a mechanical fuel injection system for big and small blocks of all makes. Kinsler made/makes mechanical fuel pumps and mechanical fuel injection systems. I also looked up Cummins diesel injection pumps when I thought about their compatibility. Perkins diesels used similar style injection pumps on their 540 V8 diesels. There are slight differences between the two fuel injection systems (big difference is fuel type and lubrication) but they both have similarities as well (one being that they're both used in direct injection engines). It could work with a little bit of modifications. Replace the diesel injectors with gasoline injectors and if lubrication of the injectors is a problem (which I don't see why it would be), find a way to improve the pump lubrication.

[@itsdavid-hq2kv]

👍👍

[@mohahareb1463]

more volume = less pressure

[@n5yiz]

All you need is GM# 12663577

[@Jommybutler1234]

It is odd that he shows what appears to be an LT4 engine on the stand and what appears to be the LT1 high pressure fuel feed pipe.

[@smoothdrive3055]

Gm gang!!!

[@fredflintstone7778]

Wow, you're a rocket scientist...!!! Lmao

[@pryotex]

I want to see the guy who uses plain neoprene fuel line and tries to fire it up.

[@levenwhite5388]

I went to order the part and the shiping was 3.00 less then the part itself needless to say I didn't order it just because of that

[@zacharymorris9917]

Are you going to cry about it?

[@barryscarlett1647]

Gen 4 . Mods be good . Lt1

[@groomlake51]

You should do some research so you understand the dynamics. I applaud your effort but you are completely wrong unless your trying to sell people injection pumps. Research cavitation in positive placement hydraulic pump like your injection pump in a multi stage system being supplied by a non positive displacement “lift pump”. Bosch CP3 or CP4 is a great place to start. You seem to have good content and want to genuinely help people I totally respect that🦾😎🤘🏽