Full exhaust vs up pipe on a turbo b series Honda

Today we test out a 3” up pipe vs a full 3” turbo back exhaust on my car. All runs are done using the same tune file with no changes whatsoever to fueling, ignition timing, etc. All runs were also completed the same morning to try and have the most accurate apples to apples comparison between the two different styles of exhaust systems.
One thing to note the car did make more hp with the midpipe and no muffler, than the up pipe, but it still made a little less than the full exhaust with the muffler. It almost seems as if the small 1.6 needs a bit of back pressure.
Setup:
B16a3 CSS block: CP 9.8:1 pistons Manley H beams
Gsr head: Valves, springs, Skunk2 tuner 3 cams
Turbo: Turbolab hx40 6264
Exhaust: 3” up pipe; 3” downpipe to mid pipe to 3” vibrant street power muffler
Fuel system: walbro 525 FIC 1650c
Fuel: Sheetz pump ethanol 74% about 1 month old
Tuner: Derf Tuned August 2020 (same file used today)

[@ericzmusic]

I think it's just exhaust velocity. A lot of cars seem to bog a bit if they don't have the exhaust attached. Surprising that such a high HP turbo setup seems to enjoy a full exhaust, though.

[@tafuentes]

Yeah both good points. I did go to the track to try and test but I couldn’t get back to back runs with and without the exhaust. I will say the 2 runs I did do with the full were slower, but it could’ve went a few different things. I’m waiting for cooler weather to try again.

[@johnmeza955]

Good video man, definitely not what i was expecting. Thats a sick del sol 👍👍

[@tafuentes]

Thank you, it definitely surprised us. We will see how the car runs at the 1/4 to compare it with my past runs on the short exhaust.

[@nicholasvonrhine6311]

There is a delicate balance between high flow and restrictions just like nature.

[@ll.7927]

Sounds way better cruising with full exhaust Than up

[@boostismagic]

I say it again, Turbo Lab kicks ass....

[@tafuentes]

Excellent turbo for the money. It’s been on this car since January 2017. It doesn’t owe me a thing.

[@Yonelll_Kim]

That band up top will be smooth once the fuel changes are done!

[@tafuentes]

Yeah I have a cleaned up map that I’ve ran at the track once. A good bit leaner and cleaner lol. I might try and see what it does on the dyno once it gets cooler out.

[@andycarbajal5493]

I see a boosted del sol, I click like.

[@tafuentes]

Thank you kind sir !

[@ricerfoo5805]

Im running same set up and wanted to see how full exhaust and top mount turbos work but i guess i should be fine , Cool vid man

[@tafuentes]

Yeah I was pretty surprised by the results. It seems if you want to make about 6-650 a full exhaust is still very okay to use.

[@ricerfoo5805]

@@tafuentes 🤟

[@ALYangRSX]

Were you tuned on the full exhaust? If you were it would make sense that you’re losing power with an up pipe. When I tuned open downpipe, I installed a e cut out and lost 30 hp with the valve closed (515-520hp). With the valve open, I was still making close to when I tuned with an open down pipe (545-550hp) Just an fyi, these Honda motors don’t like restrictions. Try tuning with that up pipe.

[@louielou8262]

That 😜 wild! Thanks for the upload new subscriber 🙌🏼

[@chowchronicles9411]

Sounds good 👌🏼

[@intheworkseg6]

You around NC? Im central NC...Thats a mean ass sol!

[@tafuentes]

Yup. Charlotte area. Thank you 👍🏼

[@X4hunterx4]

Working on upgrading my old turbo kit on my Del Sol and thinking about running full exhaust..

[@californiaracing5099]

Delsol is badass man

[@tafuentes]

Thank you !

[@ivangranillo]

Sick del sol brother whats the name of the racing front wheels?

[@tafuentes]

They are VMS drag wheels. I’m not sure the actual name but the brand is VMS.

[@Loustylz203]

I had that same issue the turbo was sucking in the gasses and it literally made 60hp more

[@tafuentes]

Yeah that’s what my tuner thinks happened in this case. Once it gets cooler out I may try and do another back to back dyno test with the cleaned up fuel map I have and I will try to have a secondary exhaust fan running by the up pipe.

[@justinmike2zrfe]

Oh so this makes sense why when people do just the turbo downpipe they may extend it a little bit further out instead of just a couple inches off the turbo up

[@TheNonnell]

Great video! Have you made your decision about running full exhaust vs up pipe?

[@tafuentes]

I feel like I will run it with the full exhaust for the time being. It’s quieter and doesn’t seem to be holding the car back.

[@Wyzral4vid]

best sound of turbo bseries. what exh manifold you use? turbo have twinscroll?

[@torquise518]

hey man any chance you know the brand of the downpipe, ive been looking everywhere to get one i cant get the right size

[@tafuentes]

I’m pretty sure it was spit industries. I know it was made for the manifold I bought about 8-9 years ago. I bought them both together.

[@joshuam1241]

*Could back pressure have anything to do with this? You fonʻt want to much back pressure but also im guessing to little back pressure could also be not so great*

[@tafuentes]

Could be a possibility, but on all the runs boost stayed exactly the same and the dyno plot’s looked almost identical to about 7-8k rpm. I’m thinking it’s more to do with the car sucking in the exhaust fumes.

[@nicolebivens4226]

What about at track? Does it trap higher with up pipe or full exhaust

[@tafuentes]

Just about 2-3 mph quicker. I’m waiting for cooler weather to try and test back to back at the drag strip.

[@brianrucker3376]

What turbo you running bud

[@zavierlopez5297]

What is the comparison when u took off the muffler but still had downpipe

[@tafuentes]

It was a little less than full exhaust with muffler maybe 5-10 HP if I remember correctly

[@zavierlopez5297]

Sounds like better i tune with full exhaust

[@jochycharger87]

👍👍👍🙏🔥🔥🔥🔥🔥🔥🔥

[@russellvwgli]

Excuse me, what muffler is that? 😀

[@tafuentes]

It’s a vibrant street power 3” inlet and outlet

[@alitoroganan2442]

Wtf i hope someone can explain what happened here, why did the full exhaust made more than a hood exit

[@tafuentes]

Like I said at the end of the video. It could be because the turbo was sucking in exhaust fumes which would make it lose some power. That can happen if you don’t have a fan directly pushing the fumes away.

[@alitoroganan2442]

@@tafuentes but the fumes are heading out towards the top away from the compressor housing

[@tafuentes]

@@alitoroganan2442 true but you’d be surprised as to how much force a turbo pulls in air.

[@alitoroganan2442]

@@tafuentes im curious bro, hopedyou did a pull while the hood down

[@tafuentes]

@@alitoroganan2442 i didn’t. Maybe another time I will.

[@slamblackek9]

What’s the best et u have on the car

[@tafuentes]

10.44

[@slamblackek9]

I’m asking cause I’m hoping to run a 10.8 to 10.9 my car was tune made about 550whp also spinning on the dyno I went to the track but had a bad my trans was because I had bad twin disc in the trans I bought the 725 now also getting my trans re done also buy brand new coil overs also new inner putter tire rods the fastest my car gone 12.77 @ 121 mph

[@slamblackek9]

@@tafuentes also are u at full weight ?

[@tafuentes]

@@slamblackek9 yeah my car weighs about 2650 with me in it. No weight has been removed other than the spare tire lol. Car still has everything in it, radio, heat, full interior, bumper supports etc.

[@slamblackek9]

@@tafuentes love it but go faster my goal is 10.5 how hp do u think I need also what did u do to Strengthen your transmission

[@terrellhubert5753]

Man that was way to rich. Lean it up to 11.5

[@tafuentes]

I agree, but the motors been ran real rich like that for almost 5 years. I have recently leaned it out to low 11s.

[@boostedlawnmower9955]

Boost is up and down

[@tafuentes]

30 psi boost gauge doesn’t read correctly over 30 psi. Once it exceeds its internal map sensor it freaks out.

[@boneyman5365]

That car needs tuning BADLY! Then you would see the real effects of an up pipe on a Honda. This vid holds no water! Sorry to say

[@ronaldgallihugh9456]

Motor has to have back pressure

[@zebulenplacke5183]

𝓅𝓇o𝓂o𝓈𝓂 💪