Head shim MPI 10-12 psi supercharger ?

[wkeggenhoff]

Anybody installing a head shim on MPI stage 2. want to run 10-12 pi on pump fuel. Looking for 220-230 hp.
Is this recommended ? Any other options needed. Want ba little more than 200 hp @ 6psi boost
Cheers Werner

 

[kinger]

Hello Werner,

What your wanting is my exact set up. I used a head shim from Ulmer that gets the compression down to 10:1 and I run 10-11 psi on 91 octane gas. The set up dyno'd 241 hp on Ulmers dyno. I had to add a in tank 255lph fuel pump to keep up with the beast on long pulls it would slowly lean out.

I have put on over 1500 miles and its sweet never missed a beat after the install and fuel pump.

Overall its my favorite set up for trail boost. MPG takes a hit though it gets around 8-11 depending how hard I drive it.

 

[wkeggenhoff]

Can you adda BOV valve to get milage bag and turn boost down if going on long ride ? Does stock injector flow enough fuel or do you replace and or bore out ? 240 hp that's just what the doctor ordered.
Did you change gearing and run external track drivers ?
Thanks

 

[kinger]

I run a BOV already a vortec unit. I am toying with a valve that I can run to the BOV and pressurize both sides of the BOV and make it run 5psi or valve it to the atmposhere and run 10psi but I haven't got it hooked up yet. The 10 psi is just to much fun LOL

Stock injectors are fine

When I got the sled it has different gearing 24/42. If I was doing a stocker I would go to a 24 or 25 top gear and be done with it. If you leave it stock it will pull even harder just wont have the crazy tops speeds possible with the power of the SC. Mine tops out around 140-144 mph now.

I have a stock driveshaft with intro/extro doo drivers on it for sale in the classifieds and I am going to run a HD shaft and avid drivers for this year for no reason other then peace of mind with such a powerful sled.

Really you dont 'have' to do anything except the head shim and a BOV in my opionion then see how you like it!

 

[wkeggenhoff]

Thanks again for all the info, gives me a peace of mind as my dealer is telling me to turbo as motor won't live Supercharged
Thing your set up is exactly what I want to run
Cheers

 

[wkeggenhoff]

Forgot to ask you what kind of fuel controller are you using and have you had any problems dialing it in ? Gems ? dynojet pc ?
Do you know what Allan Ulmer supplies with his kits
Thanks

 

[kinger]

I am using the GEMS that came with the kit. I really dont have any complaints it does everything well but nothing perfect. There is one spot at 90 mph crusing (yes the sled will 'cruise' at 90 mph) it will go very very lean you either run 88 mph or WOT just dont hold it at 90.

It used to bother me but if I have the space to run 90 mph i will be running way faster then that so it really isn't a issue, now if this issue was at 50 mph I would have a big problem but at 90 no worries. It has to do with how the controller steps into the different modes and that is just one limitation of a piggy back.

I'm pretty darn anal about my stuff and it really doesn't bother me.

What does bother me is it appears the sled start and the MPI controller are not compatible as it does something to the injector signals and the sled start doesn't register it running at all. I still need to figure that out.

Other then that it idles like a stocker and purrs everywhere, I have a well trained ear and all you hear is power I'm actually impressed it does as good as job as it does when you read all the stuff about it being junk and what not.

 

[347strokin]

X 2. I'm running about 12 lbs on a Stage 2 with a head shim. I run about 10% race fuel at 1800 feet just to be safe. I'm running the Rapid Bike 3 right now but when I had the GEMS dialed in it worked great.
Awesome sled, runs great. I don't know why your dealer would tell you the sled wont live long supercharged.

 

[machzrobbie]

I run a BOV already a vortec unit. I am toying with a valve that I can run to the BOV and pressurize both sides of the BOV and make it run 5psi or valve it to the atmposhere and run 10psi but I haven't got it hooked up yet. The 10 psi is just to much fun LOL

Stock injectors are fine

When I got the sled it has different gearing 24/42. If I was doing a stocker I would go to a 24 or 25 top gear and be done with it. If you leave it stock it will pull even harder just wont have the crazy tops speeds possible with the power of the SC. Mine tops out around 140-144 mph now.

I have a stock driveshaft with intro/extro doo drivers on it for sale in the classifieds and I am going to run a HD shaft and avid drivers for this year for no reason other then peace of mind with such a powerful sled.

Really you dont 'have' to do anything except the head shim and a BOV in my opionion then see how you like it!

Are you sure you're running 24/42??? That gear is way to low to pull 140 - it will top out at 120 ish

 

[kinger]

140 ish on the dreameter sorry never had it on radar

 

[helmic]

Calculator

140 ish on the dreameter sorry never had it on radar[/quote

Here Kinger this should help you to get the gearing bang on.]
http://www.turboaddictionparts.com/cata ... lator.html

 

[kinger]

Yeah I played with that one, not sure what I want to do with the gearing. the 42 reverse bottom gear is expensive to replace.

I had 10T drivers when I hit the speed on the dreammeter and some track spin.

 

[machzrobbie]

Yeah I played with that one, not sure what I want to do with the gearing. the 42 reverse bottom gear is expensive to replace.

I had 10T drivers when I hit the speed on the dreammeter and some track spin.

You can buy a stock 38 tooth reverse gear cheap. it would get you back close to where you need to be

 

[nate007]

Kinger,
Have you tried to mod your speedo gear yet? I took 2 teeth off of mine (180 degrees from eachother) and it's dead on now, with little or no error at lower speeds. Yeah, it's a little dis-heartening when you don't see the bigger numbers from the dream meter, but it makes it read correct. I checked mine with a couple different gps units, and its consistant with them!

 

[aja636]

Me and my dad where just talking about this. His old S/C set up was running 11-12 lbs boost on 100% stock motor with no head shim running pump gas. We had no issues with it also. Just had to be smart. Don't heat soak the engine or intercooler. keep it to 800-1000 runs at the most. But on the trails there was no problems at all. He ran the 1st gen GEMS controller and threw it in the trash. Went to a boondocker box and everything was nice from there. SPEED is the guy that came up with the in tank fuel pump. You can see his info on Dynotech. If I remember 240ish HP.

A head shim would be great insurance for ??? fuel. If your dealer is telling you to go turbo for reliablity, timw to get a new dealer, sounds like he is trying to get you on the hook for the labor bill of installing a turbo...which is 2-3 times longer then the S/C

Now we went turbos and dont have the S/C anymore, but sometimes we miss it. Yes the turbos are faster boost for boost, but NO turbo is as fun on the trails as the S/C was.