UEL + Turbo
 

Just to poll this to see your thoughts ... who would be interested if @FullBlown had a UEL option with their turbo kits?

What would be the expected performance loss? I get mixed feedback on this ... some think with proper tuning for the UEL you would not see much of a loss. (Didn't Borla claim they got more HP out of their UEL over EL?)
http://www.ft86club.com/forums/showthread.php?t=20525

:cheers:

Burble + BoV? Yes plz

Negligible performance loss. The Subaru (WRX/STI) people who claim power loss conveniently compare OEM UEL to aftermarket EL, obviously there is a performance gain to be had in that case.

I don't see this ever happening, but it is nice to dream…I'm right there with you

i wouldn't agree that the performance loss is negligible. i've seen information that would suggest very much otherwise in certain cases. and the logic is sound, as i think it's pretty well universally accepted that exhaust pulse timing is crucial on turbocharges engines. if it were negligible, twin scroll turbos wouldn't offer the benefits they do.

so might you be giving up 10-15whp under the most extreme case or a few if you're not pushing it as hard, or a lot less or a lot more, no one has really done any testing to say either way on this platform. the only thing known for sure in my opinion is that it's not a plus in any case. it always detracts from performance to some degree, due to far from ideal exhaust pulse timing.

@JDLAutoDesign has a UEL turbo setup in development if anyone is interested.

https://fbcdn-sphotos-g-a.akamaihd.n...86815016_n.jpg

https://scontent-b-ord.xx.fbcdn.net/...32421422_n.jpg

Borla UEL produced more power than the EL. Obviously, this is not definitive proof, but at least it cannot be said that it is absolutely 1000% of the times EL will outperform UEL.

that's na though. we're talking about turbocharged, where the effects of pulse timing are far more important as they effect spool, which of course itself greatly effects the powerband. i think we agree though that it's very application specific and whether it's a material concern is unknown. my point is just that it's never better to have uneven exhaust pulse timing in a turbo car. maybe there is some case where it is, i could be wrong, but it doesn't make any sense why that would be.

I'm sorry because my statement seemed absolute and extremely confident. The truth is there is not much hardcore data and I do agree performance should be less with UEL how much is the question. I BELIEVE it should not be much, but have no hardcore data to back it up. I believe I will have a UEL and EL manifolds constructed at the same time. It would be nice if I could test them both.

Yeah, this is my problem ... I wish we could get some dyno's of properly tuned car both ways. Same kits, different manifold. I would gladly give up 10-15 hp for that sound. But if I saw definite numbers of around 50hp loss or more ... than I would have to rethink this.

Does anyone have some hardcore data anywhere ... for any turbo car?

You wont see 50 whp loss. STI's in the 400+ whp see 15-30 WHP increae when going from STOCK UEL to aftermarket EL, so comparing aftermarket UEL to aftermarket EL should not be anything over 30 whp at the worst possible scenario. Just using an example, again no hard concrete data.

Edit: Interesting R&D piece form Tomei. See below, Chapter three is about exhaust manifold design EL vs. UEL and why they chose UEL

http://www.tomei-p.co.jp/news/Report-EJ25-V1.html#C3.1

that tomei piece is Hard core uel :popcorn:

If you're looking for maximum efficiency in a turbo manifold i think equalizing the pressure drop between the runners is much more important than length.

that would be awesome if you could. i'd expect results similar to what you see with ej's, but it'd be great to actually know for sure, for science lol.