hans14914

I am definitely going forced induction sometime, but still on the fence with what kit to use. At one time I was working on my own, but it never got past cad drawings. I like a lot of aspects of Johns kit, but personally, I am a water/air guy. I cant imagine a better application of air/air than Johns, but it still requires cutting the bumper cover. He managed to make the cutouts look great, but I am fixed on getting the Strosek cover, so watercooling is really the only option for me as of now.

123quattro

The problem with having a 500 hp daily driver is you get used to it. After that, everything else just feels slow.

Randy V

Why is it that this:


Becomes this:

Schmoopie?


What is that all about?

Information is information. I wonder why you are attempting to suppress it.

James-man

Schmoopie. That is funny.

Really good to hear the twin turbo S4 has come alive. That isn't just information, that is news!

Thanks for the posts.

IcemanG17

Okay I made a homemade dyno comparo with Kuhns TT at 12psi, Murf Stage 3 at 12 psi & Louie Ott's stroker.....yes its rough..but its interesting how the SC makes more torque until the turbo spools up..then lags behind it... of course the stroker trumps all....but also cost more than both the others put together!

AO

Dude... where's the love?

Fabio421

I'm not trying to suppress anything. I think the information is great. I am trying to keep you from suppressing it. I posted a similar thread about a Kuhn built turbo car a few months ago and you shut it down. I am trying to keep that from happening again.

RicerSchnitzzle

So how long until someone force feeds a stroker? Or has it been done?

hacker-pschorr

Awesome!! Boost is always a good thing. Nice writeup
There have been other threads on those projects.

Wade T

Yea, it is strange comming from a centrifical but there's so many varibles like the size of the turbos. And on the stroker, it seems peaky if you will. And IIRC, that was not dynoed on a dyno jet. It was some sort of dyno simulation?

IcemanG17

Andrew
I thought about adding yours or Woodys....but it already was getting pretty cluttered dont you think?

Wade
I didn't think the stroker was peaky....& I drove IT!!!! 400lbs of torque from just above idle to past 6500rpms...is very nice!

Z

It's going to be kind of hard to get real comparisons. In the above comparison, the Murf car is an S4 with an automatic transmission, and was run on a Superflow dyno. The twin turbo car is an S4 with a 5-speed, was run on a DynoJet dyno, and the numbers are using the higher resulting STD correction factor, instead of the SAE correction. The stroker is a 5-speed with aftermarket cams, engine management, individual throttle bodies, etc., was run on a Dynocom brand dyno, and also using the STD correction factor.

Below is an overlay comparison of the twin turbo car's chart and the very first Murf customer car's chart, from almost four years ago now. There are still some differences, but at least less of them, and it's about the closest to a really even comparison that I could come up with using the data I've got. Both cars are '87 S4 5-speeds, both runs were done on a DynoJet, both charts are using the STD correction factor, and both are stated as being internally stock engines. The Murf car is intercooled and using the stock engine management with just the FMU (stage 2 kit). The twin turbo car is intercooled and using the stock engine management with SharkTuned chips. The Murf car is using stock exhaust manifolds, an X-pipe, and stock 928 exhaust pipes. The twin turbo is using a custom dual 3" exhaust after the turbo exhaust manifolds and other turbo stuff. The most significant difference between the two is probably that the Murf car is at 10psi of boost and the twin turbo is at 12psi of boost. The thinner blue lines are the Murf car, and the thicker gray lines are the twin turbo car. It's too bad that the boost wasn't the same for both cars, but even so, I think it makes for an interesting comparison.

Vilhuer

Kuhn's setup on 6.5L stroker would be something special. His kits only real pronlem is that body needs to be cut. Its probably possible to build air/water cooling TT without cutting body but such setup will be serious plumbing compromise. "Stock" stroker build is about $10k if almost everything is done DIY style. Its clear there is no way to compete against any form of SC or TT setup on $/hp or $/tq race if hp/tq is only measure of how good system is. Now build stroker first and then add rear turbo to it...

Courtshark

Got any info on the specs of the turbos? Make, model, wheel size, etc. Also curious about the intercooler (make, flow specs). How many lbs of boost was he running? @ 8.5:1 compression I'd imagine you can run 10+ psi easily, assuming the IC properly does it's job.

I'd love to see some photos of the install. I assume it has a FMIC. Right now I am debating whether to go with the rear-mounted turbo set up or a TT set-up like this; another option is a larger, single turbo unit.

I really like the torque "curve" of the TT (more like a nice straight line), though it peaks way too soon, well before 6k. Why the power loss up top? Perhaps the turbos are running out of air... Properly matched turbos with proper IC/water injection should be able to keep producing power well into the upper power bands.

Abby Normal

You'll need to visit Pelican to get those answers. John does not post here.