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~7 degrees of KR on 3.5" pulley, please Advise

Impala131

Impala131

New member
Alright, so you may or may not remember my posts a month or two ago, but I had headers, AL104's, open cone, stock pulley, stock tune. I used the android torque app, and thoroughly tested for KR. Had 1-2* of part throttle KR, but no WOT KR. I took this as a green light to pulley down.

Then, I installed a 3.4" pulley on an MPS I bought online (knew I was going to have to settle for a 3.5, but I got a great combo deal) and scanned for KR again. This time, I got 6* of KR at WOT (IAT~90*F, which was of course unacceptable. I purchased a 3.5" pulley from a member on here, and installed it. I drove lightly until today (finally had day off and nice day to scan).

So today, the air temperature is about 50*F. The IAT was reading +or- 70*F. Remember, stock tune. When I really stomped on it, I was hitting about 6.5* of KR... much worse than I was expecting. It was all during WOT, and at this time I didn't suspect anything is banging around, because I had no KR on stock pulley. I did, however, notice that my coolant temp was about 215*F, which was way higher than I thought it might be... my dial never shows higher than 190ish.

I plan to use a 180* thermostat from now on, but I only expect that will remove 1 or 2 degrees of KR. The KR is fairly steady, peaks on the shifts but shifts aside I'm getting a good 5* of KR at WOT.

I was trying to avoid spending money on tuning, but it appears that I might have no other choice. Please, share your thoughts and ideas. Also, is it normal for the engine temperature dial to be friggin 30 degrees off the sensor's reading?
 


I hope you plan on putting the stock pulley back on ASAP before you chip a piston. Right off the bat I can tell you you don't have enough flow mods to be dropping pulleys just yet. You need some headers or a plog and get rid of those restrictive manifolds. PCM needs to be tuned for a 180tstat throw the stocker back in until you have one.

I'm going to suggest right off the back you go and read nicks modding sticky.. Your not ready to drop a pulley just yet.
 
you could just pulley down. but i think a tune is the most beneficial route. and alot of guys seem to like the idea of a bigger pulley with more added timing
 
What's more expensive a new motor or a tune..in the end having knock is going to kill the motor. A tune is way more beneficial than mods at the moment.
 


Totally missed that part damn you tapatalk. You need a tune guy! Even a mailed order one is better then nothing.
 
Don't waste your time with a canned tune. I'd advise you try and find a local to hook you up with a street tune.
 
In car tune > canned tune but of course that cost more $$$ and that's if your able to find anybody local that can tune. But if you can't it's not a waste of money getting a canned tune.
 


Huh, well this just kind of sucks. I figured with a 3.4" getting 6* of KR, then a 3.5" would be just about there. Does throwing more fuel at it help the issue? Say if I tuned it?
 
Not really.

Added fuel will just be pissing your money away and the car won't go any faster than if it had a larger pulley.
 
Sooo... are you stating that I'll either have to pull a ton of timing or pulley up? Just doesn't seem right with my mods. Will tuning do me any good then?
 
Needs a tune. ASAP. I'd go back to stock pulley for the winter, and take it to a shop for a tune. That's just me tho
 


Check and make sure your trans dipstick isn't hitting the header and that your motor mounts are good and not causing the headers to hit the firewall or anything like that.
 
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