M-90 3.0; it begins now. - Page 2 - TurboDodge.Com - Turbo Dodge forum for Turbo Mopars, Shelbys, Daytona, SRT-4, PT Cruiser, Omni and more!

Avenger · 08-04-2006, 07:12 PM

Hey Big, take a look at the Ford Motorsport 30lb injectors for your set-up. Bit more than +20%, but that allows you room for more boost later. And Lord knows they are cheap enough to find on Mustang boards, and you actually get 2 spares when you think about it! They are a straight drop-in into the stock rails too, and I'm pretty sure even the electrical connectors are the same.
My set-up is going to be basically like yours, but I'm using a GM SC instead of the Ford unit. I'm mounting the unit over the rear cylinder bank just like Harv did, and setting it up so that the bypass is controlled by a t-body vacuum source.
If you need help with the blower, hit the Greater Ohio Club GP site. I don't know the exact URL there, but my brother is very into the 3800SC scene, and he recommends that site for technical info. I can testify, some of the guys from there that I've met have been a great help to my own project.

Ntrain2k · 08-05-2006, 07:21 AM

Pete,

I would suggest you plate the top of the plenum. A direct bolt on wont last, as it is thin. There will be a lot of pressure on it from belt tension.

big_P · 08-05-2006, 02:56 PM

yes, those were my intentions. The aluminum appears to be only 1/4" thick. I'll see what I can do. I may have to fabricate a bracket that goes completely over the plenum.

big_P · 08-05-2006, 05:51 PM

But, does anyone here think that the 3.0 will be able to hold constant boost?

**c2xejk** · 08-05-2006, 06:02 PM

By constant boost you mean?

Stein runs boost every day... I have pulled 1/4 mile runs with 8+psi of boost all the way down the track... (other than the launch when I didn't have enough traction...)

big_P · 08-05-2006, 06:46 PM

....I mean the constant boost that the s/c is throwing at it.

**c2xejk** · 08-05-2006, 07:04 PM

That won't happen... atleast if you want to go legal speeds.

If the SC were constantly pumping boost in, the engine would not idle and acceleration would be only limited by the wind resistance/friction...

The throttle limits the amount of air the engine can ingest...

big_P · 08-05-2006, 07:23 PM

It was stated that I was not going to run high boost, because the setup is non intercooled.

**c2xejk** · 08-05-2006, 07:40 PM

Let me put another way... What would happen if you ran a normally aspirated 3.0 at WOT (ie. 0 psi boost)?

big_P · 08-05-2006, 08:05 PM

The Eaton M-90 supercharger, while driven slower by the underdrive pulley, is still throwing massive amounts of air into the engine. If I get a lot of "part throttle boost", as said by Ondonti, will this effect the longevity of the engine that I just rebuilt.

Avenger · 08-06-2006, 04:32 AM

Shouldn't affect a properly built engine at all. My brother's GM doesn't seem to make boost with less than 50% throttle, or not more than a pound or so.

**c2xejk** · 08-06-2006, 06:21 AM

Any boosted engine can/should get part throttle boost...

On a normal drive, I bring up part-throttle boost a lot with Stein... But still while cruising on the interstate, Stein is deep in the vacuum... Cruising at legal highway speeds, Stein will pull 10-15 in Hg...

Tip into the throttle and boost comes up QUICK. Which causes RAPID acceleration. Point is, most of the time is spent in vacuum...

Ntrain2k · 08-06-2006, 09:01 AM

I think if the motor is properly rebuilt, boost whould only affect the longevity of it based on the drivers right foot.

I.E. Hammer it all the time, it wears out faster...