is it a safe setup to run a 2.75 or 2.65 upper with stock lower and stock blower, i need more torque and want more whine out of the eaton :rolling: if i run a 2.75 what other pulleys should be changed so i dont get slip, running 2.90 right now w/ all stock pulleys... 14lbs w/ current setup...
2.75 pulley on stock eaton w/ stock lower??
- Thread starter Venomm
- Start date
I have a stage 4 port and a 2.76 upper with stock lower. i need to put a 4lb lower to bring my #'s up. I made 13.5 psi and fell of to 13.2. Stock tensioner. I made 457/447. I have seem guys make more than me without a port. that is why I need the lower
im at 462/455 w/o port.... ?? will going one size smaller on the pulley to the 2.76 from the 2.90 cause loss or gains... numbers seem really low for havin a port??? im lookin to get 530rwhp out of the stage 5+..... but till then i want a quick fix
i've got a 2.76 upper only. everything else engine related is stock (lower pulley, unported eaton, t/b, fuel pumps, inj's, maf, etc.). it still even uses the factory belt. i originally wanted a 2.93 upper only because i was afraid about pushing a daily driver, but the shop i used (hpp in dfw) talked me into the 2.76. Manny told me i'd get alot more tq hit lower in the rpm and they felt confident about tuning it safely for long term. i've been daily driving this car since early october with zero problems.
Right my car is not moving enough air. the port is not functioning. I need to spin it faster.
Pluss tuned in middel of summer and it was hot and humid. 98 degrees. tons of humidity. that did not help. And every car is different.
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Yah its safe as long as you get a good tune, i made 456/478 with intake,exhaust,2.76....Id get some BF idlers to go with the upper, dont wait for one of the stockers to go out...
I AGREE, im just afraid once i get mine ported it might become less affective w/o dialing in the right set up...
That's what I run...a proven winner...
what tuner are yall using ?? dyno tune or hand held, i have diablo amazon tune right now but would prob need retune if i go from the 2.9 to a 2.75
You'll be fine with a 2.65 or 2.75 and stock Eaton. I would get an aux idler to prevent belt slip but the other idlers aren't "needed".
You don't need a to throw any more boost at that car until you find out what is holding it back. You're missing over 50rwhp/rwtq, who tuned your car and what were the parameters of the tune?
Has nothing to do with needing to spin it faster, most likely a tuning issue.
Why?
It depends, if the car was tuned through the MAF the extra 1-1.5lbs of boost won't throw the tune off. If you got tunes through Rick @ Amazon and have the lifetime revisions go ahead and have him email you new tune for the smaller pulley just to be safe.
96Stanggt, you have some impressive #'s on your signature 
Every car is different. There are mayn variables. And how far close to the edge you want to run the car is up to you and what you want the tuner to do.
Like I said my car has stage 4 w/ 2.76 upper. MaFIA,JLT in the fenderwell, and Bassani catted X and Cat back.
The car was dyno tuned. I want a safe tune. I can not afford to blow a motor. I am luckey to keep the car.
It made 13.58 psi. Rpm max at 6500. And A/F was in the 11.8-12.0 range on the sniffer My clutch went not long after.
What Perameters do you speak of ?
and yeah I know someone who made 490hp with a stage 3/2.76 but his tune was running way to lean A/F was upper 12's and hit 13 a few times.
Like I said my car has stage 4 w/ 2.76 upper. MaFIA,JLT in the fenderwell, and Bassani catted X and Cat back.
The car was dyno tuned. I want a safe tune. I can not afford to blow a motor. I am luckey to keep the car.
It made 13.58 psi. Rpm max at 6500. And A/F was in the 11.8-12.0 range on the sniffer My clutch went not long after.
What Perameters do you speak of ?
and yeah I know someone who made 490hp with a stage 3/2.76 but his tune was running way to lean A/F was upper 12's and hit 13 a few times.
OP: Personally I don't think it's worth it to swap pulleys from a 2.90 to a 2.76 to pick up maybe 5hp/10tq or less. Not to mention the 2.76, and especially the 2.65 will likely put your MAF on the edge or pegged. I think the best move for you is to upgrade your idlers but most importantly the aux idler with a good fitting belt. You could easily pick some hp/tq because you may have a little slip now and not know it.
When you're ready for a big gain just port it, there's some amazing porting deals out there right now! :beer:
When you're ready for a big gain just port it, there's some amazing porting deals out there right now! :beer:
keep the 2.90 get XCAL3 can idler pulley....??
I have a 2.76 upper only with an upper idler on a stock eaton it put down 465 rwhp and 501 rwtq. No issues at all. I would not go thru all the trouble of replacing the 2.90 IMO just wait and port what you have and add a lower
I'm not talking on a ragged edge tune. With a nice safe tune with mid 11's AFR and 21-23* of timing you should be at 490-500rwhp easily with that combo. What octane are you using and what did your tuner set max timing at?
I am not sure where he set the timing at. I only use BP 93.
Guess my car is a underachiever:cryying:
I doubt that man, sounds like a tuning issue. With the MAFia you should have enough fuel to supply the power your car should make with those mods. Who tuned the vehicle?
01cobravortech
Banned
All tuners aren't created equal and maybe its time for a straight shot type filter. I'm not a big fan of dyno tunes. Mine was tuned on the street and I think that makes a world of difference in what kind of power you really see.
I hope so I 60lb. injectors and a BAP. also have a gords dual pass HE
I always side on caution with cooling and fuel.
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