i don't get it.

[98svtconvert]

i have a 98 cobra with a 1.5 ltr kenne bell. made the numbers in sig with a stock motor. since then i have had the motor rebuilt with stock length rods and 5cc dish pistons. i added long tube headers as well. heads and cams have not been touched and are stock. the 6 psi pully was 3.25 inches. i called kenne bell and asked for a 12psi pully. they sent me a 2.25 inch pully. the car is seeing 16 psi on the dyno. intake temps were at 200. the outside air temp is only in the 40's. we couldn't make a full pull do to heat. i called kenne bell and they insist that the pully i have is for 12 psi. i ordered a 2.75 and a 3 inch pully. will try again after i change them. my question is, what would cause me to see so much more boost than what i should be seeing. with their 6psi pulley i was seeing 6psi so i just don't get it. any help is, as always, appreciated.


Justin

 

[Bad03gt]

If ur intake temps are 200 sound like u need a new heat exchanger pump. Or a meth kit

 

[98svtconvert]

it is a non i/c supercharger. i have a meth kit but we have not sprayed it yet. the idle iat's were 150. tuner said that with that small of a pully the temps were going to be to high even with the meth. it's 40 outside right now and during the summer it can get to upper 90's-100 degree's outside. i am just trying to figure out why i am seeing 16 psi on a 12 psi pulley.

 

[crazycarlo]

i dunno if anything....... you should be making less with the longtubes and all.

 

[RSbeast]

Perhaps you fixed a boost leak during all your replacement stuff? Or the 12psi pulley is designed to run a different crank pulley?

 

[MLS]

Maybe cam timing is off.

 

[SVTContique]

jesus 16psi on the stock internals... ouch.

 

[MLS]

Maybe imrcs are closed and blockinflow making extra boost

 

[98svtconvert]

Maybe cam timing is off.

that's what i was thinking but aren't the mod motors interfierance motors?

jesus 16psi on the stock internals... ouch.

not stock internals. diamond 5cc dish pistons and mahle rods.

 

[BajaBoy]

that's what i was thinking but aren't the mod motors interfierance motors?

IDK from experience but i have read it will still "run" being one tooth off. But im sure you would notice this upon the first start up

 

[MLS]

They are interference motors but there is slack in the keyways. Maybe they screwed up during porting.

 

[crazycarlo]

do you have any underdrive or overdrive pullies on the car? It says the kit comes with a 5 inch underive pulley.

 

[98svtconvert]

i removed the imrc's when i installed the S/C. heads are stock, no port work. what is the easiest way to check the cams? or is there not a quick way.

 

[MLS]

+1 to crazy carlo

 

[RIO RED SNAKE]

yea i am with crazy carlo as well...i have a 8 psi pulley on mine..with the longtubes i was seeing 8lbs of boost..then i put the stock manifolds back on but they are ported and now i see about 10-12lbs of boost on the 8psi pulley...i am curious to see if she goes kaboom now with the 10 psi pulley...but i have a meth kit and a iat to go on....but for your situation..i would see about a diff crank pulley..i think anything smaller than the 10psi pulley then you DO need a diff crank pulley..and spray that meth homeboy

 

[98svtconvert]

when i bought the kit in 2005(i think it was), i don't remember changing any pulleys. just adding the idler pulley. i still have the stock crank pulley. with the 6 psi pulley i saw 6 spi. put longtubes on and had the motor rebuilt with forged internals. i put on, according to kenne bell, the 12 psi pulley and i am seeing 16 psi. i called KB to verify that they gave me the right pulley and they said yes. i bought some bigger pulleys to put on to drop the boost. what size pulley is anyone running to get 12 psi? i am going to put the 6 psi pulley back on and see how much boost i get. i think kenne bell's info is messed up. they gave me a 2.25" pulley for 12 psi. i think that is way to small.

 

[98svtconvert]

and spray that meth homeboy

i would love to get to spray it. i can't even get through a full pull on the dyno to tune without it. my intake temps at idle were 150 and went to 205 under throttle and it's only 40 outside. i am really starting to think kenne bell gave me the wrong pulley.

 

[SVTContique]

i would love to get to spray it. i can't even get through a full pull on the dyno to tune without it. my intake temps at idle were 150 and went to 205 under throttle and it's only 40 outside. i am really starting to think kenne bell gave me the wrong pulley.

???

You spray the meth while running the pulls, it will cool the IAT's and allow you to run advanced timing as well.

 

[Toasty]

i have a 98 cobra with a 1.5 ltr kenne bell. made the numbers in sig with a stock motor. since then i have had the motor rebuilt with stock length rods and 5cc dish pistons. i added long tube headers as well. heads and cams have not been touched and are stock. the 6 psi pully was 3.25 inches. i called kenne bell and asked for a 12psi pully. they sent me a 2.25 inch pully. the car is seeing 16 psi on the dyno. intake temps were at 200. the outside air temp is only in the 40's. we couldn't make a full pull do to heat. i called kenne bell and they insist that the pully i have is for 12 psi. i ordered a 2.75 and a 3 inch pully. will try again after i change them. my question is, what would cause me to see so much more boost than what i should be seeing. with their 6psi pulley i was seeing 6psi so i just don't get it. any help is, as always, appreciated.


Justin

kenne Bell is retarded when it comes to ordering bits for their older 1.5.

Call them again and explain the situation that you are seeing 16 psi with the pulley they shipped you for 12psi.

The newer 1.7 and 2.1 use different pulley sizes to get their psi ratings than the 1.5l does. I went thru EXACTLY the same issue with KB sending me teh wrong pulley for 8 psi.

 

[96S/Cobra]

I had a 1.5L KB on my car for years, but I sold it last year. I gave the new owner the owners manual that I had, and it had a chart in there showing what pulley size equals what psi.

Back when I had it, I called the KB tech line and they told me that 12 psi was max for the 1.5L. I had my engine rebuilt with forged internals so I wanted max boost, but they told me it wasn't a good idea to run that much psi everyday all the time. They said it was fine to swap to the 12 psi pulley at the track, but to stick with the 10 psi for all other times, so that's what I did.

Unfortunately I don't remember what size equals what psi, but I know that a 2.25" pulley was is too small. I want to say the 2 5/8 = 12 psi and the 2 3/4 = 10 psi. Again, if I had the owners manual there is a chart in it denoting which is which. I'm sure they got in a hurry, were thinking about a different blower instead of the 1.5L, and they told you the wrong size. Like has already been said, call them back, explain the situation, and hopefully they will get things squared away for you.