After switching from the 3.12 pulley to the 2.87 pulley, my car hesitates in the 2-3 shift and then continues as if nothing happened. By hesitate, I mean that it literally feels like it cuts all power and then goes back to normal in a split second....almost feels like the rev limiter but I have mine set to 7300rpm yet shift at 6500-6800. The only way it doesn't happen is if I short shift at about 5800-6000rpm, there it won't do it.

What could it be? The 1-2 shift is fine and the 3-4 shift is fine as well...it's just the 2-3 shift. It's not slipping or anything, it just hits a blank spot and then goes on.

 

did you retune after changing pully?

 

its probably the tune

 

Yes, I did. If it were the tune, what could be wrong to cause it to hesitate only in the 2-3 shift? I run osiris btw.

 

i've seen this issue come up with a few folks on here...seems to be an issue with the load tables (whatever that means).

 

Hmmmm....I could play with that.

 

Hahaha....my injector duty cycle is over 100%!! Do you guys think that could be the problem...lol. I'm going to have to drop down to the 3.12" pulley.

I'm running 600cc injectors on the oem returnless system. Should it already be running out of fuel?

 

with the pulley your running i heard it was only around 80% duty cycle...

 

+1 you should be fine with the 600cc injectors.

 

600 Inj and 2.87 i made up to 399whp on dyno dynamic in TX summer, no problem.
Sounds like tunning issue? Jared@uprev tuned my car at last, did put down 420whp with added stage 0 RFS. But jared mention i don't need it at my power level but if i have it's good.

 

I didn't log IPW with the 2.87 pulley but I have a log with the 3.12" pulley and when I calculated the IPW it came out to 93% on the 3.12"....I can only assume the 2.87 will be 100%.

Keep in mind I have no fuel return system...just the stock setup with a walbro and 600cc injectors. I checked out a fuel injector calculator and it seems to add up.

Anyone have 600cc or smaller injectors with no fuel return pushing 400+whp?

I didn't exactly put 400whp but after installing the cutout my car does seem to feel a lot better with it open then it closed ( I dynoed 360whp with it closed ).

 

I honestly don't know what to tell you....timing is good and A/F ratio is good...what else could there be?

 

I run the 2.87cc pulley with 420cc injectors, no problems at all.

 

With no fuel return? Hmmmm....why are my IDC's so high then?

 

I'm sure that's with a fmu

 

BTW- I installed the 3.12 pulley again and everything is fine now....errrrrr....

 

Yes, it is with the vortech fuel system.

 

The vortech fmu raises fuel pressure, it cannot be compared.

 

Apologies, I was not aware you were running something different.

 

how can you check the duty cycle of the injectors? IPW (injector's pulse width) is available in cipher?

keep us posted on how it goes..