is anyone running with a 2.8 pulley and 42.5 injectors? Any probs???
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From: Phoenix, AZ
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From: WNY
I've been running the 2.8 with my stage 2 for 10 months now. I haven't had any problems - But I also don't make a habit of going past 5k rpm. I getting 60lb'ers and a tune this summer anyways so I don't have to worry. Too much research and documentation out there not to.
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From: RTP, NC
Your AFR's are plenty safe (11.5-12) on a 2.8 and 42# injectors up to a 7k redline.
If you look at the several I blew up my engine threads you will see most of them are running bigger injectors and they are running a richer AFR ( 10 -11 )... I haven't read any threads where a piston popped because of a lean condition.... Just a thought...
If you look at the several I blew up my engine threads you will see most of them are running bigger injectors and they are running a richer AFR ( 10 -11 )... I haven't read any threads where a piston popped because of a lean condition.... Just a thought...
I have been running the 2.79 and my GM stage tune for a while with no negative repercussions.
I went to the now out of business VT racing for dyno time at 3 different times.
once stock
once with stage 2
once with my stage 2.79 (as I call it)
all in all it ran very rich with stage 2 on it. When I slapped the 2.79 on it leaned it out a bit.
when I look at my dyno charts right now to me it looks like the tune is attempting to balance the a/f in stages. it starts a little lean then adjust, finds that it is still lean then adjust a third time where it ends up a bit on the rich side.
I went to the now out of business VT racing for dyno time at 3 different times.
once stock
once with stage 2
once with my stage 2.79 (as I call it)
all in all it ran very rich with stage 2 on it. When I slapped the 2.79 on it leaned it out a bit.
when I look at my dyno charts right now to me it looks like the tune is attempting to balance the a/f in stages. it starts a little lean then adjust, finds that it is still lean then adjust a third time where it ends up a bit on the rich side.
What where your dyno results with the 3 different runs?
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From: between heaven and hell
I run the Stage 2 injectors + tune, Injen, and a catback exhaust.
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From: Socal
I see your located in cali, and from your sig pic it looks like damn near you live at sea level like me. I run it perfectly fine until 6grand, then the AFR starts to climb back up at a slight level. It ends up somewhere in the 12's right before the redline hits.
I run the Stage 2 injectors + tune, Injen, and a catback exhaust.
I run the Stage 2 injectors + tune, Injen, and a catback exhaust.
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From: Saginaw/Fort Worth, Texas
I wish I had some input of value to add to this but I don't. The only thing I can say is if you are one that believes it is not safe don't run it. For the people that believe it is safe, then run it. All in all if something goes wrong put the stage 2 pulley back on and use the warranty you bought the kit for. Just M.O. try not to take offense.
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From: Phoenix, AZ
everyone i know who's blown their motor is because of being lean in the 4th cylinder. but it's always the big injector, small pulley guys... I haven't heard of anyone here in AZ who's blown their motor with a 2.8 & 42's
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From: Mesa, AZ
Thats because they are not running lean like everyone thinks they are. Just because the injectors are at or over 100% IDC doesn't mean they are lean, it means the injectors are working really hard to maintain a fairly rich AFR. The are also not running high amounts of cylinder pressure and heat like the 2.5-2.6/60s guys are. Poor coolant flow to cylinder 4 is a major problem and high IAT2 is fatal in most cases.
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From: Still fixing others mistakes.
Thats because they are not running lean like everyone thinks they are. Just because the injectors are at or over 100% IDC doesn't mean they are lean, it means the injectors are working really hard to maintain a fairly rich AFR. The are also not running high amounts of cylinder pressure and heat like the 2.5-2.6/60s guys are. Poor coolant flow to cylinder 4 is a major problem and high IAT2 is fatal in most cases.
just because you are runnin 11.8 a/f, seeing no knock does NOT mean it is safe.
what is the cylinder temps? dunno? hmmmmmmm
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From: Mesa, AZ
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From: Still fixing others mistakes.
this is why the egt is so important!!!!!
if your a/f starts to climb the closer you get to 7k this is a sign that your injectors are going static. mine is doing the same thing.
2.8 and 50 lbers would be peachy.
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From: Orange CA
On most boosted motors 12.8 is about the max you want to go but there are many many many factors such as: air temp, octane/gas quality amount of boost and combustion chamber design. On any motor you really dont want to run ritcher than 11:1 because then you are washing down the cininder walls and your EGTs skyrocket.
I have beel looking at my spare fuel rail and there is a problem on the inlet. it almost completly blocks off the first injector im not shure if that is cilinder #1 or #4
I have beel looking at my spare fuel rail and there is a problem on the inlet. it almost completly blocks off the first injector im not shure if that is cilinder #1 or #4
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From: Orange CA
Like i said 12.8 is relative and if you notice i said that is max on a boosted car. Most NA guys run about a 13.5. Oh the other thing i thought about was if you run to rich there is a chance of burnning your exaust valves or getting them so hot that they will cause detonation .
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From: Still fixing others mistakes.
most NA honda guys run 13.5
the rest of the world runs 12.8. who ever told you that 12.8 is fine for a boosted application is on crack. i never ran that in my gxp on bottle. it was sitting at 11.8 a/f
hell my tsi ran 12.1 with water injection, the gsx ran 11.3.
denny, it apprears the only cylinder in danger is the number 4.
i ran out of money, so i can't give you concrete answers on egt temps yet
the rest of the world runs 12.8. who ever told you that 12.8 is fine for a boosted application is on crack. i never ran that in my gxp on bottle. it was sitting at 11.8 a/f
hell my tsi ran 12.1 with water injection, the gsx ran 11.3.
denny, it apprears the only cylinder in danger is the number 4.
i ran out of money, so i can't give you concrete answers on egt temps yet
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From: Still fixing others mistakes.
Awesome an old DSM guy
Yeah I know about number#4 I just talked to Al "WITT" he told me to add the EGT on number#3 for an accurate reading of them all.
Im going to order one today, I really need to know whats going on.
Damn its getting expensive these mods.....lol....
Ah well!! money spent towards prevention is better then money spent fixing.
Yeah I know about number#4 I just talked to Al "WITT" he told me to add the EGT on number#3 for an accurate reading of them all.
Im going to order one today, I really need to know whats going on.
Damn its getting expensive these mods.....lol....
Ah well!! money spent towards prevention is better then money spent fixing.
wheeeeeeeeeeeee
the tsi never broke, the gsx was broken every two weeks like freakin clock work.
anyways, i was just going off my dsm knowledge of putting the probe in number 4. what really sucks is we don't have full control over individual cylinders, such as timing and injectors. that would solve a lot of problems
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From: Orange CA
most NA honda guys run 13.5
the rest of the world runs 12.8. who ever told you that 12.8 is fine for a boosted application is on crack. i never ran that in my gxp on bottle. it was sitting at 11.8 a/f
hell my tsi ran 12.1 with water injection, the gsx ran 11.3.
denny, it apprears the only cylinder in danger is the number 4.
i ran out of money, so i can't give you concrete answers on egt temps yet
the rest of the world runs 12.8. who ever told you that 12.8 is fine for a boosted application is on crack. i never ran that in my gxp on bottle. it was sitting at 11.8 a/f
hell my tsi ran 12.1 with water injection, the gsx ran 11.3.
denny, it apprears the only cylinder in danger is the number 4.
i ran out of money, so i can't give you concrete answers on egt temps yet
Most na cars dont like lower than 13:1 they load up and dont acelerate as fast.
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From: Phoenix, AZ
NA can run a higher AFR than Forced Induction... but for the supercharged cobalt, 11.8 is not safe. Otherwise, Cameron, you would still have a running car! I guarentee your mods with a 11.0 AFR would be still running today... but since you were 11.8, you blew your motor up.
11.0-11.4 max for the Cobalt IMO.
11.0-11.4 max for the Cobalt IMO.
Those 42lbs injectors are for the pulley they came with and the stage 3 pulley 77.9mm vs 76mm, not much of a difference. I had the 2.8 with stage 2, but the car ran like crap. Limp mode, felt sluggish after hitting the rev limiter, etc...
If you want to be safe, use the 60lbs and tune them in with HP Tuners. The results are much better, as some of the guys here claim. Check out tag racing, New Era, etc...
Hope this helps
If you want to be safe, use the 60lbs and tune them in with HP Tuners. The results are much better, as some of the guys here claim. Check out tag racing, New Era, etc...
Hope this helps
