E36S50

What will it take to get 350 reliable, lag-free RWHP from a '91 turbo?

Is is possible to get this level of power with the stock turbo? I was thinking of a good exhaust (no cats), large intercooler and more boost & fuel. I am not opposed to a larger turbo but don't want to spend the $$$ unless it is necessary, plus I don't want anymore lag than stock!

Does anyone know what these 315HP cars dyno at stock?

Thanks

James.E

Headers, 1 bar on electronic boost controller, cat/muffler bypass and K&N will get you close. Then add K27HF, 964 cams.... Oh, and remove the O2/lambda conection, made a huge difference to my car...

Sameer

E36S50,

your ride already comes with the bigger intercooler and K27 from factory. What you would need is to run at 1 bar, headers, muffler and air filter.

set your CO to around 3% and dyno your car to see if you need more fueling, if you do than get either the Andial fuel enrichment or the Lee rice enrichment.

That will give you the power you want.

KeithC2Turto

I think stock C2T tests around 270-280 rwhp at stock .8 bar boost. (boost gauge goes to .7 bar)

I'd vote: a good full service first.

Then remove cat, add 1 bar spring, set co to 3-4%, check A/F & boost on dyno, shim spring till get full 1 bar measurement from the manifold section after the throttle. Most 1 bar springs only get around .9 w stock headers.

May need an adjustable over-boost switch or relocate a new stock switch to manifold section.

Also a good idea to relocate the boost feed from the 69EZ ignition module to the manifold section as C2T's have been known to blow these. You get a pretty big boost spike here when the throttle is slammed closed at high rpms on boost in the turbo to throttle body section. I think the factory did this with the late C2T's.

Should get you to about 330-350 rwhp.

Then, if you need more, I'd like to try the Koklen turbo for a solid 350-370 rwhp. The K29's & other bigger k27's will reduce your low end kick some but will make it fly at high rpms. I tried the K29 & HF's. Again they kill on the top end. The K29 came in with a bang at 3800 rpm and the HF came is soft early with a very smooth transition. Almost like a normal aspirated motor. I missed the low kick of the 7200. The Koklen might be a better balance of early boost & increased mid range rpm efficiency. But I have not tryed one myself.

Expect 5-10% more hp from the bigger turbos with potential lean condition above 5500 rpms.

The more I learn I don't know if I'd spend the $3k on a header set. I suspect that most of the gain is from the weak waste-gate circut tricking the wg to deliver more boost than the stock design does. But that is just my guess.

Keith
C2T with all the goodies.

Adrian

Purchase the 370 HP RCT or 425 HP RCT Evo kit from RUF. The latter I believe in the US will cost $US23,000. Check out Weissach the RUF distributor for the USA and Canada.
Ciao,
Adrian
964C4

C2 Turbo

Adrian,
Regarding the RUF HP #'s,are they at the wheels or at the crank.Thanks
Later, Yasir

fc-racer

The RUF RCT EVO is based on the NA 3.6L motor, not the 3.3L turbo motor.

Staffan

Keith
Have you done this ?
Where is the orginal location and where should it be moved ?
I am currently looking for a place to read boost pressure for my EBC, will check this out right away.

Thanks
Staffan

Adrian

Dear FC-Racer,
You are 100% correct. I missed a line out of that post. I meant to say purchase a 3.6 l engine and the RCT kit. RUF HP figures are always at the crank. Always seriously conservative as well. RUF no longer sells the kits for the 3.3 l Turbo or the 3.8 normally aspirated engines unless you ask really nicely of course and are prepared to pay a little more. Generally they are no longer available.
Ciao,
Adrian
964C4

fc-racer

As huge of a fan of RUF as I am, I still don't think this would be the most cost effective route or provide the greatest value to this individual. Considering he already has low compression pistons, an intercooler, turbo and intake plumbing, it would be silly to start with over with a 3.6L NA motor and repurchase all of that. Instead, some mild upgrades such as turning the boost up slightly, a cat bypass and a mild turbo upgrade would likely get him where he wants to be without major expense.

Vince5

FYI for the 3,3T RUF have what they call the BR kit, which is basically what is often recommanded on this board, 0,9bar spring, decat then they have there own camshaft and they work on the air flow. They take the power up to 360/370hp and assured me it gives less lag. Only draw back is the price which is hardly competitive