Huntley Racing

We have designed the manifold for the 32V car with the 16V in mind. They are totally different but will have the same 'feel' and 'look' with the different pattern and smaller plenum to keep the power range in check with the RPM potential of the motor. The kits for the 32V will likely be $6000 but no real pricing yet. The 16V will either be packaged without injection or with stand-alone EFI since we don't want to use a hokey additional injector or other substandard enrichment device. We are looking for input on this. The EFI is not cheap. Once we are done with the 32V application the 16V should take very little time to complete.

Drewster67

Time to pick your Brain -

For us ROW Owners, what may we expect from a supercharger installation.

My 84S2 (16v) has 310 stock and roughly 265 rwhp. What rwhp would you speculate the final range would be, with a SC?.

Thanks for answering my previous questions.

Jim Nowak

Drew,

Check out: <a href="http://www.superchargersonline.com/hp_calculator.asp" target="_blank">http://www.superchargersonline.com/hp_calculator.asp</a>

I have a custom supercharger kit on my 1986 560 SEC with CIS-E injection. I picked up the exact Dyno Jet RWHP that the formula from superchargersonline uses. I'm running around 11 psi of boost in my car and the difference in horsepower and torque is amazing. I'm running a methanol/water injection system to cool the charge. Without the methanol/water injection I was retarding the timing by 10 degrees at full boost. Now, I can run full advance when the methanol/water injection is activated. I eventually want to add a permanent air to water intercooler but I was trying to do my project for as little as I could. Total investment on my kit:

ATI P1SC with blowoff valve = $2,200
Custom bracketry, pulley, tensioner, plumbing & connectors = $1,000
MSD boost timing master = $200
Methanol/water injection kit = $300

I have not dynoed the car with the methanol/water injection but I feel I picked-up quite a bit of power. When the methanol/water injection hits it feels like I've activated NOS and the tires immediately break loose.

Drewster67

Jim -

Thanks for the link - On paper at 5 pds of boost=

HP Loss due to timing adjustment: 0
Est. flywheel HP with supercharger: 415.4
Est. rear wheel HP with supercharger: 332.32
Total HP Gain: 105.4 flywheel HP
Percentage Gain: 34 %

Impressive I will say and it only gets better with more boost. Now if I can only find I practical/affordable supercharger for my s2.

Jim V

Jim,

I'll shoot this at you also:

Although the KE is differnt from the plain k-jet on my '79 it should still apply.
How did you determine that the injection system would take the extra air and what mods did you have to make if it didn't?
It's my understanding from asking around and reading here and there that the K-jet on nearly every application is oversize and will maintain proper A/F ratio with any mods that increase the engine's airflow ( bigger TB,boring or stroking),
but, there has to be a limit and I assume when that once the plate bottoms out you start going lean with any additional air.

Any thoughts?

Jim Nowak

Jim,

I feel you can use a boost sensitive rising rate fuel pressure regulator in series behind your stock FPR. In theory, it should work fine. The 911 CIS turbo tuners should know how well it will work. I bought one for my CIS-E car but didn't need it at the boost I'm running. I may need it at another 5 to 10 psi but then again I'd probably need to fire-ring my heads too.

I sold my old Paxton based supercharger kit to a guy in Canada and I'm in the process of helping him tune this system. He is having an overly rich condition at 5 psi. His Mercedes uses the stock CIS, I guess it is K-jet, like the 928. The rich condition, I feel, is caused by his lack of a bypass valve and the pressure is forcing the CIS metering plate too far down at idle and partial throttle. With a blow-off valve he should be able to aleviate his issues and have a perfect running engine. His system currently uses a pop-off valve that is set to release the pressure at 5 psi. The pop-off valve is good as a safety device to avoid over boost but it does not work well if there is not a bypass valve used in conjunction. The bypass valve also allows the tranny to shift under vacuum when he is not at full throttle. I found venting the bypass to the atmosphere works as well as rerouting it to the supercharger intake.

Huntley Racing

To answer the power question....we have seen 30% to 40% gains in the 944 based cars we have supercharged. The reason we can get as high as 40% gain is because we are spending lots of time engineering the manifolds to flow very well at higher RPMs where peak HP occurs. The EATON blower, being a positive displacement unit, has almost too much bottom end grunt. You never really hear about tourqe increases since 'HP sells', even though 'TQ wins races'. Anyway, we found that by changing the manifold from the typical street style (long runner/small plenum) to a race style (short runner/large plenum) gave us the top end that the Eaton couldn't and therefore good all around performance. What we strive for in power delivery is a very flat TQ curve and a steadily building HP curve to redline. The custom intake with the Eaton gave us that on the 16V 944 S2 (baby 928 S4). Look at the link below for the dyno chart from a SC 944 S2.

<a href="http://www.huntleyracing.com/superchargerkitpics/images/2/stage_2_dyno.gif" target="_blank">http://www.huntleyracing.com/superchargerkitpics/images/2/stage_2_dyno.gif</a>