sentry65

iTrader: (11)

well I ended up going with an MSD booster pump and upped the fuel pressure by overdriving the fuel pump when it reaches a certain level of boost pressure. I think of it as a short term band-aid fix, but it does work really pretty great. I'm gradually raising pump voltage from the normal 12 volts to something like 13.5 volts at redline. I just have to take caution to make sure I have 1/4 tank of gas so that the pump doesn't overheat since sitting in gas is what helps pumps stay cool

otherwise I have the CJM stage 2 pipe ready to go in, but I think I'll wait for the CJM twin fuel pump assembly and do it all at once since it's probably doubtful the stage 2 hard line will solve it - especially given that the booster pump is able to cram enough fuel through the stock one

that's all I have planned. I'm running 750cc injectors and even they didn't solve my fuel pressure issue - if it's the same issue you have. The good news is I have more than enough fuel in terms of the A/F ratio.

The other thing I might try is the Cobb tuning ECU software when it's released, but not sure yet if that'll offer anything to mess with fuel pressure.
The last resort is to do a 2nd smaller fuel tank kinda like the AAM stage 2 fuel system

oh, one thing that I think helped a little for an extra 2-3 psi of fuel pressure was connecting the fuel pressure regulartor's boost line to the blower itself instead of the intake manifold. I dunno if my SSV was having inconsistent boost pressure, but the blower won't lie

rocks

iTrader: (1)

Has anyone thought about using one of these for a returnless system?
http://www.aeromotiveinc.com/pdetail.php?prod=32

I have been talking to a shop that turbos mustangs and vettes with returnless systems making upwards of 800whp without a return. But they are able to modify the Pulse Width of the intank fuel pump from the factory ecu. I dont see why we are not able to do something like this on the Z even if it requires using a external unit like the aeromotive.

gsazabi

iTrader: (51)

Sorry for the late reply guys, I just got back from work.
The pulley was on the car for about 7,000 miles.
The leak was pretty severe; I ended up replacing the seal and put the stock
pulley back in.
I think I will stick with stock pulley for now.
I did think about getting the UR, but I have big stereo system setup so I'm afraid it might not be a good idea.

Well my point is that this will not happen on every single KJR installed. I could just be one
of few unlucky ones. I'm just giving you guys heads up on what can potentially happen.

Audible Mayhem

iTrader: (48)

hey bartzen, why cant you rev past 6000 with the CJ motorsports system, you should be able to rev as high as you want if the properly matched injectors are in there

pm me cause i will forget about this thread, there is no reason you shouldnt have full range, i have installed a couple 3.12 pulleys lately with CJ motorsports RFS with only 440 injectors and it works perfectly

booger

iTrader: (6)

I had the KJR alum. crank pulley on for just a couple thousand miles if that . There was a good groove already dug into it . I wouldnt run one of them for nothing . And if you have one on now , take it off ASAP

MustGoFastR

iTrader: (13)

Both the KJR and CNR pullies are succeptible to this problem since they do not have a steel sleeve like the UR pulley does to prevent the oil seal from wearing a groove. There IS a fix; it was posted in one of the other threads about the issue. You just need to get a hold of the proper steel sleeve and sleeve the pulley yourself (the part number and where to get it was posted as well).

I had a CNR pulley that I ended up replaceing with a UR one (got a good deal on it and didn't feel like messing with the sleeve). I replaced the oil seal as well, but there was really nothing wrong with it. At some point, I'll sleeve the CNR pulley and resell it, I guess...

Ztalker

my UR pulley's been installed for two and a half years(daily driver)...no issues.

cvt

iTrader: (1)

you sold me that pulley....

booger

iTrader: (6)

Didnt know then...what we know now ...sorry dude !

gsazabi

iTrader: (51)

LOL

gargoyleZ

iTrader: (4)

The KJR pulley I had failed also. There was a vibration in the engine bay, I could not find it. Narrowed it down to the pulley. The OEM one is dampened and without it causes vibrations. Once removed, I found the key way grooved and expanded. I stuck with the OEM one, and won't be changing it. There are quite a few threads (as I remember) that address a few different and the same issues. I never heard from KJR either.

cvt

iTrader: (1)

ii've actually had the pulley on for around 10-12K miles and 14 months...no problem so far. I am concerned as the gains i felt were minimal and for the damage it can potentialy cause is quite severe.

gsazabi - how much did you pay for the replace at west covina?

sentry65

iTrader: (11)

something I've wondered about crank pulleys is what flywheel are people running with theirs?

I mean, if you reduce the weight at the front of the crankshaft by 2/3, shouldn't you reduce the weight at the other end (flywheel) by roughly the same amount? Otherwise I'd think trying to spin something that was dramatically heavier at one end could end up being bad for crankshaft bearings

I know that has nothing to do with the aluminum wearing down on the KJR, but might have something to do with excess vibration. The big heavy stock crank pulley was put on with the stock flywheel in mind

Motormouth

iTrader: (44)

I am looking at a lightweight pulley

I have a ACT prolite 14lb flywheel. what ratio difference is that?

sentry65

iTrader: (11)

the stock flywheel is 25 lbs

so 14 lb flywheel is 56%

KJR is slightly over 2 lbs
UR pulley I think is about the same as the KJR as far as weight


I'm not sure if it's an exact science or if it's even true, but just something I wanted to bring up since the flywheel sits on the other end of the crankshaft and is supported directly by the crankshaft

gsazabi

iTrader: (51)

I'm running JWT flywheel, which is 13lbs I believe.

sentry65

iTrader: (11)

yeah i dunno, you didn't have vibration though, the pulley itself wore out due to the aluminum being weak

actually I think the JWT is 14 lbs
http://www.jimwolftechnology.com/cus...asp?PartID=430

baptist

I got rid of mine when I had my engine built, didnt do anything worth noting, and the engine builder didnt think it was a very good idea to use it.

gsazabi

iTrader: (51)

It was free of charge All covered under the warranty.
I just had to bring my stock pulley and pay for a new belt cuz I lost mine.

Barzten1

iTrader: (18)

At about 5800 I my fuel pressure drops and after 6500 its dangeously low. Kind of the same issue Sentry65 up above was having. Im using 550 inj and I think he is using bigger. Maybe if I went down to 440's Id be better off.