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3.5" or 3.6" pulley

2

2004l67

New member
I'm finally ready to give in to temptation and drop pulley size.

The zzp charts are a little confusing. The car is a 2004 Impala SS, but they say 3.5 should be stock. Mine is no doubt 3.8.

I'm running Autolite 104 plugs, 180 tstat, 2.5" catless zzp downpipe, and a very basic tune. Have at most .2-.5 of kr under very heavy acceleration.

Can I do a 3.5, or err on the side of caution and go 3.6?
 


zzp charts are complete BS ... don't drop pulley until you see 0 kr. that .2 -.5 will likely turn into much bigger numbers when you put a smaller pulley on , even a 3.6 .
upgrade your intake and consider getting a powerlog . then rescan and go from there.
even though zzp's chart is BS info , keep in mind a gen V SC needs more supporting mods than a gen III. their claim of a 3.5 being ok for stock is for gen III and it's still wrong.

read this thread....twice
http://www.grandprixforums.net/threads/17482-Safely-Modding-Your-3800-Powered-Car!!
 
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EHB said:
zzp charts are complete BS ... don't drop pulley until you see 0 kr. that .2 -.5 will likely turn into much bigger numbers when you put a smaller pulley on , even a 3.6 .
upgrade your intake and consider getting a powerlog . then rescan and go from there.
even though zzp's chart is BS info , keep in mind a gen V SC needs more supporting mods than a gen III. their claim of a 3.5 being ok for stock is for gen III and it's still wrong.
Click to expand...


FWIW, my car has a Gen 3 blower on it. Hence some confusion, their website makes it sound like it should be a Gen5.

The .2-.5 or so is really worst case. I could make a few WOT passes thru the gears and not see anything. Gonna order the plog for not to quench my need to mod. :)

Intake is the stock airbox with a K&N drop in. I seem to recall reading somewhere the 04+ air boxes actually flow a lot better than the older ones.
 
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Idk why but that just seems like a lot of knock for a car with a downpipe, colder plugs, and a colder tstat on a stock pulley. I am willing to bet that if you had a better tune you could run a 3.6.
Yup only cars that got the Gen 5 were the 04+ GPs. IIRC after 2005 they were the only cars available with a supercharged 3800.
 
2004l67 said:
FWIW, my car has a Gen 3 blower on it. Hence some confusion, their website makes it sound like it should be a Gen5.

The .2-.5 or so is really worst case. I could make a few WOT passes thru the gears and not see anything. Gonna order the plog for not to quench my need to mod. :)

Intake is the stock airbox with a K&N drop in. I seem to recall reading somewhere the 04+ air boxes actually flow a lot better than the older ones.
Click to expand...

ok well the fact that you're seeing any knock on the mods you already do have with the gen III , proves that zzp is full of crap. you've already went beyond what they say you need and still see kr. what did you gap your plugs at ? are you using 93 octane? the amount of kr you're getting isn't a big deal in itself , but as slick pointed out , you shouldn't be getting any at all. the plog will wipe out the rest. put the plog on and get the 3.5 , scan and retune accordingly.
 


I want to say I gapped them at .50.

Think I'm fine with that k&n drop in, or would I be better suited to some sort of FWI? I played around with a cone filter and a little bit of piping, but couldn't get it into the fender enough to shield it from engine heat.
 
Lol engine heat.

Flow > Temps.

Unless you plan on making some exhaust system that routes the crossover under the transmission, it's not going to make a difference no matter what intake you come up with.
 
you could always wrap the cross over with header wrap . not sure how much it helps , but it certainly can't hurt none.
 


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