I have a D1 with a 15psi pully on it and i am only seeing 11psi on the boost guage, any ideas? I am runing the new ATI Inlet tube.

 

I think the way they rate their pulleys is on stock motors. So depending on what work you have done to the motor it will change. Like my self I have a 10lbs pulley and am only seeing 8. Plus with it being a procharger you can chaulk a lot of it up to belt slip

 

That pulley may show 20 lbs on another car... Like Wicked said, it really depends on what you have done to your motor... what exhaust, what cam, what head work, etc. The only other thing you could check is your air filter.

What size pulleys are you running? I have a 7.6 crank pulley and a 3.4 blower pulley and I see 15 lbs on my motor..

--Sean

 

Are you running SDCE or is that with a stock ATi tensioner??

 

boost is a measure of restriction not of volume....

 

SDCE tensioner with a 12 rib belt. I guess it is time to throw the 20psi pully on

 

Do you know what pulley sizes you have saint?? Screw it, give that D1 hell

 

xxsaint69x what Crank and Blower pulley's are you running, 7.6 and 3.4???
I beleive the D1 has a few hundred more RPM capability over the D1SC which I have.
The more efficient the Motor is the less boost you can run on a Certain pulley size. Just wondering Saint but what heads, cam, intake, exhaust, intercoolers, ETC are you running. Give me a run down on your car specs. You made need a big 18-20lb Pulley to see 15lbs of boost, I wanna know b/c I need to find out what sixe I need for my setup VRE 383, LE AFR heads, d1SC FMIC shooting for 12-15lbs with a Small mid to high 220 duration cam.

Also how do you like the SDCE peice, I plan on getting one soon but i have heard of no Slip issues with it, and thats usually with the 8rib Ls1 guys.

 

SDCE tensioner, canned that POS ATI tensioner last time it broke. Went with an ATI SuperDamper and Big Block Snout Hub too ..

--Sean

 

well i just took the blower off to grind down the ABS bracket, looked at the pully and its a 4.25, i looked at the crank but i could not see any numbers on it. the heads are LT1 CNC, CC305 Cam, FMIC, Hooker Longtubes, 3inch ypipe, GMMG. I have another pully and it is 3.70. With that pully im suppose to be seeing 19psi. Any ides waht kind of crank pully i might be running?

 

Just measure it.. and I would bet if you put that 3.7 on, you'll see your 15#'s ..

 

Saint I really couldn't tell you (I could do some Math and figure it all probably but i am Lazy , lol) Sounds like a Pretty good setup and take that 4.24 Blower pulley off, the 3.7 should do the trick with the 15lbs, hell Depending on the RPMs your pulling at 3.4 would yield even more. Who is doing your tunning???


Sean94Z what do you tihnk is wrong with the SDCE peice, was your aligned properly, I am not at all calling BS but I have seen a lot of guys run 15lbs+ with them with no problems. How much is the setup you are running now with the Cog and what is your Boost level??

 

Are the D1 and P1 crank pulley sizes different because I have a 3.7 pulley on my blower now and I only see the 8 lbs??

 

There is NOTHING wrong with the SDCE piece, I think it's awesome .. I said I got rid of the POS ATI Tensioner after it broke the 3rd time .. I don't have a COG, I have the ATI Superdamper and big block chevy snout connected to a 12-rib 7.6" v-belt pulley, then to the SDCE Tensioner and up to a 3.4" Blower Pulley. I see 15#'s on my motor..

The guys over at SDCE are great. Scott has a good shop going and great customer service.

 

I am running a 388 stroker (8.8:1 compression), huge Griffin intercooler, F1 (22 psi) with the ATI tensioner... no belt slip. I'd say that you would have to do a pulley swap to get your desired boost. Your engine and it's supporting cast have a big part in what kind of boost is made.