JW in Texas

Kirk,
I like the Blown Six gauge too. I'll probably end up ordering one. Lots of good information in a clean package.

I was thinking, you might want to contact the seller of the SoK set up on Ebay & see if they can give you a part number from one of the injectors. Might help in decoding what you will need with yours.
J

Jeff Curtis

R6XTERRA, in those pics, you are missing the reinforced/modified factory motor mount (the long "span" mount from motor mount to motor mount) that the tensioner assembly bolts to. These are modified by SOK and pre-drilled for the tensioner...so if that part did not commence with the sale, you have some work to do.

Just a "tip" from someone who has installed a few of these kits...good buy by the way (from what I understand).

KirkF

Jay,

I asked and they replied that:

The diameter of their pully on the blower is 2.5"
Injectors are MOTORCRAFT Part # CM4719 {#F1SZ9F593B}; Red; E9SE-B1B
I cross referenced them to be the ones used on 1990 Ford Thunderbirds with Superchargers

At 55 PSI these injectors would flow 33.733 lb/hr (354.54 cc/min)
Using the Max Hp calculators with .6 as a BSFC I still dont get numbers that work out. (270 hp @ 80% duty cycle) close to 300hp @ 95% duty cycle.

Kirk

JW in Texas

Kirk,
That's what I figured. I just talked to Cory @ Planet 9Eleven who has the other SoK car that I mentioned earlier & he agreed. SoK never made a system that used stock compression. Your pulley is the same size as mine so you will need to go to the 9.0:1 pistons.

I also found out from him that the race car he has with this setup puts 500hp to the ground @ 12psi, race gas only! Has 110 race hours on it so that tells you how reliable these can be when done right

KirkF

Well that was the pulley on the EBAY setup, we'll see what my pulley is when it comes in.

If the compression has to be lowered the next question is how SoK did it. Did they machine the existing pistons down or replace the P&Cs with a lower compression set.

I asked a question about lowering compression on Pelican, and Steve from Rennsport replied that you shouldnt use spacers at the bottom of the piston, because the increase in deck height can cause unwanted detonation. He didnt think I could reach 9:1 by machining the pistons without weakening them too much.

Jeff do you have any input on this?


Kirk
The joy of hobbies is that they keep you poor enough that you cant get into trouble elsewhere.

JW in Texas

Cory seemed to think it was done with machining.

Cory Jump

I have never seen a SOK setup that was designed to be used with stock compression on a 3.6. I can get you some photos of the pistons that are machined to 9.0 to 1 compression ration as used in all of the SOK setups that I am aware of. A good friend of mine has also built quite a few of these engines over the years. The version I have is using the larger whipple blower running nearly 12 lbs of boost and a mass air setup. I ran it on the dyno three weeks ago and it made 498 rwhp and 540 ft lbs of torque. The same day i dynoed my E class 964 with fresh stock class legal engine that made 248 hp. Too bad I couldn't sneak this thing under the decklid.
I have installed some of the tpc kits on boxsters but don't have any experience with the 3.6 911 kits.

The SOK setup makes serious horsepower and torque and as JW has said makes it feel like you have a big block out back.

Unfortunately it is not a bolt on kit for a stock engine.

Cory

this one is destined to reside in a backdated 87 carrera chassis that is now a longhood RSR.

KirkF

Cory,

I am hoping when the parts arrive that they are similar to what Jay has. Copying his setup will probably be the easiest way to go.

(Mine might have a different pully size but I should be able to get replacements from somewhere)

If you can get a picture of the pistons I can have some place like Supertec do the machining for me.

If you happen to see any of these engines out in the near future, detailed pictures would be great.
In particular the main engine mount, which it looks like SoK beefed up and mounted one of their pulleys on. Measurements of where the pulley went, and what thickness of metal they used for any strengthening would make my job easier.

The other question will be the injectors. I'm curious what models were used on the various SoK installs.

What about cam shafts?


Kirk

P.S. I'm glad to hear there are a couple guys with experience on this setup on Rennlist. You guys are making this alot simpler for me!

KirkF

Another question:

What is the manufacturer and model number of the superchargers that SoK used?

Kirk

JW in Texas

Kirk,
I emailed Zane who originally had this motor & his response was:

"Yes lower compression is a must. The stock pistons were milled - just like Ruf used to do and many others.

I'm pretty sure the injectors are Ford 5.0 Mustang. They're enough for street use so that it's easier to tune. Larger injectors are required for a track motor - along with a lot more fine-tuning."

Zane knows Alois Ruf very well. His response should be accurate regarding the pistons.

I also dug out the cam specs. The company that did them was C&P Performance, ph# (770) 922-1613 (circa 2000). The specs are:

Stock: Lift: .464 intake; .425 exhaust
Duration: 240 intake; 230 exhaust

SoK specs: Lift: .400 intake; .400 exhaust
duration: 245 intake; 260 exhaust

Recommended rocker arm ratio of 1.3

Their grind # FRA-45-60

I also have the SoK brochure that gives some info. The supercharger is a Whipple. I used Kenne Bell for my rebuild a couple of years ago when it started using some oil. Ran around $ 900.00. Might be a good idea to refresh yours before you go to the trouble of getting it installed.

Email me your fax# & I will send this stuff over so you can take a look.

pcarcraig

Kirk you have a PM.

KirkF

I wonder what they mean by recommended rocker arm ratio?

I asked on Pelican and the rocker arm ratio for a 911 is

1. Cast 2 valve 911 Porcshe rockers are 1.45 :1.
2. Forged rocker both adjustable and solid are 1.5:1.
(Courtesy of Henry Schmidt)

The formula for changes to lift due to rocker arm ratios is:
New Lift = (Current Lift / Original Ratio) * New Ratio

I dont know whether the recommended rocker arm ratio number they supplied means anything or you just ignore it?

How does this cam behave in your car? How is the idle? Does it work well on the street? I assumed you have been using your SoK porsche mostly for street use and your GT3 as your track car. (Have I mentioned I am jealous?)

Kirk

JW in Texas

Kirk,
It has some lope but it's not crazy. The cam & exhaust note sound a lot like my 327/350hp, '66 Vette with side pipes when you are standing next to the car. The midyear Vettes use chambered , straight-through side pipes which is similar to the SoK car. Add that supercharger whine & it makes for a very distinctive sounding car

I'm not sure on the rocker arms. Mine may have the stock ones for all I know. That's just what the cam spec sheet said.

Zane put about 10k track miles on this motor when it was in the RSA. I use it mainly on the street these days but since the cup stays at a track over an hour from the house, I have been driving it here on the new track, Eagles' Canyon, that we have being built nearby. They are awesome on the track when set up right. That seamless power is great for squirting you out of the corners & they build some serious velocity very quickly

KirkF

Still waiting for SC to arrive...

Kirk

KirkF

The supercharger arrived on friday. Unfortuneatly today I had to leave town for the next two weeks for work. But I had a chance to look through the parts and take some pictures.


The intercooler is 21" x 11" (Which I assume is the larger size offered from SoK)