Upsetting dyno day
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Joined: 02-23-10
Posts: 205
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From: Stratford, NJ
Upsetting dyno day
Well to start thing's off the numbers in my sig were from my old cobalt that got hit from behind and totaled. Last year I went to Race proven Motorsports to get my stage 2 kit put on and a custom tune. 3.0 pulley 42's i/e thats all. I made 222/198 on 91 octane, which I was pleased with. Although yesterday was when my biggest disappointment occurred. I installed my zzp stage 3 h/e, 2.9 pulley and kept the 42's, brought it back to RPM for a tune and made the exact SAME horsepower WTF?! The only thing I gained was 10ftlbs of torque. I know alot of you guys are making 240-250 with my mods. I just dont get how this could be. It was on a dynojet so the numbers have to be pretty dead on.....right?? Anyway the tuner (roshan) said the car stopped making power on the top end, around 6300 to be exact. Could it be the injector's? Im thinking about getting 60's and a retune. I know this is a pointless post but I just wanted to vent to people who understood where i was coming from.
Please any and all suggestions would be appreciated.
you're probably lacking fuel up top. 42s can be done on a 2.9 but a very experienced ecotec tuner would need to be involved. i have a 2.9 and made 280whp in bad conditions along with stock exhaust and stock cooling mods lol. so now still on my 2.9 i easily see me sitting 290+ 
Well to start thing's off the numbers in my sig were from my old cobalt that got hit from behind and totaled. Last year I went to Race proven Motorsports to get my stage 2 kit put on and a custom tune. 3.0 pulley 42's i/e thats all. I made 222/198 on 91 octane, which I was pleased with. Although yesterday was when my biggest disappointment occurred. I installed my zzp stage 3 h/e, 2.9 pulley and kept the 42's, brought it back to RPM for a tune and made the exact SAME horsepower WTF?! The only thing I gained was 10ftlbs of torque. I know alot of you guys are making 240-250 with my mods. I just dont get how this could be. It was on a dynojet so the numbers have to be pretty dead on.....right?? Anyway the tuner (roshan) said the car stopped making power on the top end, around 6300 to be exact. Could it be the injector's? Im thinking about getting 60's and a retune. I know this is a pointless post but I just wanted to vent to people who understood where i was coming from.
Please any and all suggestions would be appreciated.
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Joined: 02-01-11
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From: modesto
no i ran 42s with a 2.8 pulley 11.1 afr with a 50shot of nos all the way to 7500 rpm....
it pit down 310 and 295...
i do have many other mods and a built engine
wat was ur iat2s on the dyno?
was ur air filter clean?
wat kinda oil do u run and wen was the last time u changed it was?
wat kinda gas do u run?? chevron...shell....
wen i was on gas i added a lil 110 with the 91 to help with the kr..
I've found the iat2s on the dyno r higher than the street...most will agree i hope.
it pit down 310 and 295...
i do have many other mods and a built engine
wat was ur iat2s on the dyno?
was ur air filter clean?
wat kinda oil do u run and wen was the last time u changed it was?
wat kinda gas do u run?? chevron...shell....
wen i was on gas i added a lil 110 with the 91 to help with the kr..
I've found the iat2s on the dyno r higher than the street...most will agree i hope.
I wouldn't let RPM touch my lawnmower.
Your customer (myself) brought his Cobalt TC SS to you to install spherical jointed lower control arms that we make here. He drove the car on and off for a few weeks then drove down to meet with me and other Cobalt owners at an event near Knoxville TN. The tail of the dragon its called, 318 turns in 11 miles.
When steddy arrived, I was already there in the parking lot. He got out of the car and he complained to me that the car did not respond well to steering inputs and took off when braking. I immediately road tested it. Did not have to go far. The lower ball joint cross pin was not tight I thought.
Sure enough, the drivers side cross bolt and pin was loose. I torqued it, 37 ft lbs, back off 3/4 of a turn then 37 ft lbs. Done.
Decided to check the other side.
I was totally dismayed. No nut. The cross bolt has witness marks where it has been itching against the recessed groove in the ball joint pin, this knuckle is not a tapered ball joint fit.
The nut is a K nut mechanical fastener it cannot in my experience , back off. I suggest the tech started it a thread or two and forgot.
I am sure you appreciate the risk to the customer. I am sending him a new knuckle and cross pi, we double nutted and loctited new nuts to get him home.
thanks
When steddy arrived, I was already there in the parking lot. He got out of the car and he complained to me that the car did not respond well to steering inputs and took off when braking. I immediately road tested it. Did not have to go far. The lower ball joint cross pin was not tight I thought.
Sure enough, the drivers side cross bolt and pin was loose. I torqued it, 37 ft lbs, back off 3/4 of a turn then 37 ft lbs. Done.
Decided to check the other side.
I was totally dismayed. No nut. The cross bolt has witness marks where it has been itching against the recessed groove in the ball joint pin, this knuckle is not a tapered ball joint fit.
The nut is a K nut mechanical fastener it cannot in my experience , back off. I suggest the tech started it a thread or two and forgot.
I am sure you appreciate the risk to the customer. I am sending him a new knuckle and cross pi, we double nutted and loctited new nuts to get him home.
thanks
I have a co-worker that has an LS2 that keeps chewing up cams they've installed along with putting parts in his valve train that weren't what he ordered.
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Joined: 02-01-11
Posts: 2,799
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From: modesto
man i can't believe that wow....i would go back there with a gun and stand over the guy doin the work while he fixed it again...
im will in to do work for cost of parts and a case of beer..lol depending on wat it is...
im will in to do work for cost of parts and a case of beer..lol depending on wat it is...
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Joined: 02-01-11
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From: modesto
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Joined: 09-29-06
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From: california
You know someone with nothing but problems from them and you take your car to get worked on and are mad at the sub-par results? Dump them as your tuner, Get some 60's and atleast opt b. These car's make hp all the way to redline even with a GMPP crap tune... Your sitting at decent stock numbers with beyond stage 2 mods something is really wrong! What kind timing advance you have? Is the car sound mechanically? For the record ive seen factory freaks completely stock down to the factory paper filter put down more HP/TQ than you do modded!
I work at a big place...a more proper term would be 'guy I know, that happens to be employed in the same general square acreage'
So no, I didn't go there post **** storm.
Well.... A guy with not so much experience on cobalts will not take the 42s to their max level... But it can be done.... But it would be easier with 60s so its worth a shot......
Thread Starter
Member
Joined: 02-23-10
Posts: 205
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From: Stratford, NJ
no i ran 42s with a 2.8 pulley 11.1 afr with a 50shot of nos all the way to 7500 rpm....
it pit down 310 and 295...
i do have many other mods and a built engine
wat was ur iat2s on the dyno?
was ur air filter clean?
wat kinda oil do u run and wen was the last time u changed it was?
wat kinda gas do u run?? chevron...shell....
wen i was on gas i added a lil 110 with the 91 to help with the kr..
I've found the iat2s on the dyno r higher than the street...most will agree i hope.
it pit down 310 and 295...
i do have many other mods and a built engine
wat was ur iat2s on the dyno?
was ur air filter clean?
wat kinda oil do u run and wen was the last time u changed it was?
wat kinda gas do u run?? chevron...shell....
wen i was on gas i added a lil 110 with the 91 to help with the kr..
I've found the iat2s on the dyno r higher than the street...most will agree i hope.
I just put a brand new spectre air filter on. i know its not the best brand but it was 20 bucks.
I run shell 93
Thread Starter
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Joined: 02-23-10
Posts: 205
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From: Stratford, NJ
Also i know i deff need a new tuner but they were there only reputable shop i know besides Tune Time in south jersey, but i've heard that they have blew a few motors. I only dynoed at 200whp bone stock and as far as i know the car is mechanically sound. I just replaced the fuel filter, air filter, spark plugs. The car runs good has a great idle and the only thing that bother's me is the s/c coupler which I have the part in my back seat. Honestly i rarely take the car above 4500rpms unless I come across a nice roll race which also I may only take up to 6500rpm.
Do you guys think just a new tuner will solve it? Or should I throw 60's on there with a new tune and call it a day? 2.9 is as far as I want to go for now, the car has 80k miles and I know these engine's last a long time with good mantinence but I just want to be sure. The car does feel a little bit fast and deff has more torque then before the 2.9 pulley but I know there is more power in the car and I have to find it!
Is there anybody/place near the tristate area that you guy's could recommend? Even one of you guys that knows how to tune these car's well.
Do you guys think just a new tuner will solve it? Or should I throw 60's on there with a new tune and call it a day? 2.9 is as far as I want to go for now, the car has 80k miles and I know these engine's last a long time with good mantinence but I just want to be sure. The car does feel a little bit fast and deff has more torque then before the 2.9 pulley but I know there is more power in the car and I have to find it!
Is there anybody/place near the tristate area that you guy's could recommend? Even one of you guys that knows how to tune these car's well.
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Joined: 02-23-10
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From: Stratford, NJ
And thanks for the input everyone! greatly appreciated!
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From: california
Well that's good. Like i stated even on a GMPP tune these cars make hp all the way to 7K so if your tuner wasnt going past 6300 there is something wrong with the tune or the car! Im hoping the tune but only you would really know if the car s sound mechanically! I hope you get this figured out cause most people even factory stock dyno above 200 hp and about 200 tq!
A trifecta tune is inbetween a canned tune and a custom tune. For an lsj HPT is the way to go. Unless you like running pig rich.