PureMuscle

How come Chevy would lie about the hp on the Z28, I'm thinking that its because it makes the vette look a whole lot better and so people buy it, but it seems like there should be a better reason than that.

V6toZ28

Yep ... and if you take a conservative 280 rwhp and assume a 15% drive train loss you still come out at 330 at the crank still over the factory 310 rating.

But they didn't underate them so much, that everyone can realistically expect to see 300+ rwhp stock and presume that there is something wrong with the car if it isn't ... there's a lot that do go over 300 ... but more that don't


But not the same exhaust, intake, smog nor the same tuning ... more than enough differences to account for a 40 hp rating delta between the f-body and the 'vette.

Having the same basic engine as the 'vette doesn't automatically determine that the f-body has the "exact" same hp rating ...


Now all this presumes a Dynojet dyno. Go to a Mustang or another load bearing type dyno and a stock f-body will typically put down between 265 and 275 ... pretty much spot on a 310 factory crank rating ...

Agian people like to brag about thier dyno numbers. I know of one shop with a load bearing dyno that was losing business to the Dynojet dynos because his numbers were lower ... so he just re-calibarated to give out higher numbers ...

95TA8280

How much will a compression ratio gauge cost me?

Anyone give me exact directions on its usage?

Bad AZz Z28

nope thats the reason, and possibly to make it alittle better with the insurance companies, but by now they arent fooled when they see 'camaro' haha either way, its not a huge underrating, but its there.


And the oil consumption problem should be your main concern. It is not just alright for a motor to burn oil, nor should it be left unchecked to work itself out. and Ive heard it is a more prevalent problem in LS1s, so look into it. Burning oil piston slapping motors will not put out the power you expect, fix that and you may get better results.

nikkev

Don't feel bad about your numbers.I dyno'd 275/275 with my '98 Z A4.Your tranny also has a lot to do with the numbers.You do need to get the oil consumption checked though,especially with only 12k miles.My '98 goes to the track all summer and drives me to work every day and burn less than 1/3 a quart every 3k miles.Good luck...

Antz97ZNJ

seems low, but get yourself some track times

95TealLT1

If the car is a 2001 with 12000 miles on it should be under warranty. Just take it back to the dealer and pitch a bitch.

Your oil consumption is way too much.

Good Luck,

Al

95TA8280

I don't know what I would say at GM with the warentee. I mean, I can't go up and be like "I think the car dyno'ed less than it should". About a month ago a mechanic there said that 1 QT/1000 miles is extreme, but common....

How exactly do I check my compression?

95TealLT1

You don't need to say anything about the dyno.

A quart every 1000 miles is not common. I would ask to speak with his manager and if that doesn't work I would call GM. There is a number in your owner’s manual. Don't take no for an answer. At a minimum they need to do the trouble shooting to determine there is nothing wrong. Just get loud about it.

Remember, don't take no for an answer.

Good Luck!

ULTIMTEORANGESS

at the very least bring it in for a consumption test.at worst you get a free oil change.

95GRNZ

Like mentioned before, you take off the spark plug, screw in the compression gauge and crank your car. And if you buy/rent the gauge, I'm sure the instructions will follow.

Or, if you are taking your car in for the oil consumption, tell them to do that. Saves you a lot of hassle.

And yes, your numbers are on the low side, but nothing extraordinary. When I dynoed my car, there were two completely stock 01 T/A's which both dynoed in the very low 280's.

TS

95TA8280

The car is going to the dealer on Tuesday, I'm gonna have them do a compression ratio test. Car was bought about three months ago and I haven't done an oil change (driven it about 2000 miles) should I do it this weekend, or let it sit until they take a look at it?

95GRNZ

I'd just let it be as it is.

TS

sleeperZ96BT

I frequent the dyno place that he goes to. It is a Dynojet dyno. So we are taking an M6 2001 LS1 making 274 rwhp, which is about 325 at the crank figuring 15% drivetrain loss. That may be uncommon, but its not unheard of. It's possible there may have been a correction issue somewhere. Who knows, but if I had to guess at a problem, I'd say somewhere in the spark area. Possibly a bad coil pack? There was a 00 TA that dynod like 210rwhp and it turned out there were 3 bad coil packs. Got the new coil packs and it bounced power right up to a lil over 300rwhp. Did you happen to scan and see if you were picking up any knock? Post a dyno chart if you can, that may help out. Like they said though, oil consumption would be my concern......a quart every 1k miles is a LOT, even for an LS1 from what I have experienced.
Brian

95TA8280

Would a bad coil pack make my car run bad? It's been running fine, no misfire, studder, etc.

I only got a A/F done, and a graph is in my original post, on the bottom of the linked webpage. The car does have piston slap at startup on cold days also.

Question on compression ratio: do I have to test all 8 cylinders, or just one per head? Around what should my CR be?