Mister Will:

I think your stock dyno #s are pretty low for an M6. 282 rwhp/291 rwtq is 15-20 off from what it should be, in my opinion. Do you have any baseline dragstrip #s?

Was it a dynojet?

Maybe the correction factor was bogus..

Did you dyno the FIPK on the same dyno? It does look like you got a gain from that..but 26 rwhp is kinda unprecedented..especially if that was on a mustang dyno. Your car's performance is now on par with a stocker. There may be some other factors in play.

 

wholy ****,
did you get the 12.64 with those mods, or what mods exactly did u use to get that kind of time?

 

It's not that great, is it? It was pretty good for back in the day (2000), but plenty of others have done that by now.

I had drag radials (hence the 1.8 60ft). I decided to list the power mods in my sig because of the 5-line limit. My best time on street radials was a 12.8@111. Both of those runs were with 323 rwhp and these mods:

Whisper Lid
ATR cat-back
Home-ported MAF
FRA, TB coolant bypass, little stuff like that
3.73s and hypertech w/o the power program installed (corrected the speedo)

~3600 lbs weight with driver. M6.

I drove a 99 TA M6 with essentially the same bolt-ons but with 3.42 gears to a 12.7@109 on drag radials. This was all at 1300 ft. All you need is a good 60ft in an M6 to run 12s.

 

If he has a Z28/Trans Am... I dont think he Dynos low... In fact its a good dyno number. Its still over the Factory rating by 20hp. (305-310 to his actual hp which is around 325hp) If he has a SS/RamAir/Firehawk, then thats another story. If that was the case then 298-318 is a good stock dyno run.

 

Just because it's 20 over what it's rated at doesn't mean that's enough. It should be 40 over what it's rated at. It's only good if it's as good as what everyone else is getting. Remember, it's an M6 and not an auto.

On average, stock M6 LS1s dyno at ~300 rwhp. He's 20 hp below average. That's a weak LS1, if it's from a dynojet with the proper correction factor.

And there really isn't a difference in the power level for a "standard" LS1 and an SS or WS6. It's a minimal difference, at best. Some (many) "standard" cars dyno higher than the fancy ones and run quicker/faster quarters.

 

Ok... NOT all LS1s are going to dyno 300+ rwhp... just like NOT all LS1s are going to run 13s. And i would hope that a damn Firehawk/SS*345hppackage* would dyno more to the wheels than a standard LS1 equipped car. Considering the $$$ youre wasting. Something I dont really like Seeing a Firehawk dyno 302 RWHP and then here comes a Z28 that dynos 316RWHP from the factory... Somethings not right there...
But anyways... i understand what youre trying to say...

 

Who's to say what is average ... I dynoed 278 stock ... on a 2001 ... and the best I ever got out of it stock was a 13.58 on a 2.0 60'.

I've seen lot of Z's dyno under 290 stock ... I've also seen a few folks game the dyno to inflate thier "stock" numbers ...

 

I ran those times with 302rwhp!! Then again... mines a 35th ann convertible

 

GUYS

We aren't arguing over a little 20HP are we

It late here on the west coast and I've got to be up early tomorrow. I'll comment on the above later

 

It seems my car's output has been the topic of discussion lately.

I dynoed my car, a stock 98 Z28 hard top, at on a Dynodynamic dyno several years ago. The numbers were in the 280 rwhp and 290 rwtq area. Last fall I had the engine tuned. So I took the car to the same speed shop to be dynoed for a fresh baseline (the car was still bone stock). The numbers I got are in the sig. 282 rwhp & 291 rwtq. While I was disappointed the HP figure wasn't up near 300, I knew that was an optimistic expectation.

After following this board for the last 6 years or so, I know that rwhp figures of about 280 are typical for a '98 LS1s. So I had to be content that I did not have a factory freak......damn

While in the speed shop, I picked up a K&N FIPK. After installing it, I came back (2 weeks later) and dynoed the car again. The resultant figures are in the sig. The only change was the FIPK. 26 rwhp gain.

Now remember I just drove the car in off the street for the original baseline run. Perhaps the fram air filter was getting plugged up?

As I said before '98 Z28s typically dyno around 280 rwhp. With just the FIPK, output raised to 308 rwhp. Since then I have installed a cat-back which is in the sig. Since most cat-backs increase output by 10 - 15 hp. Therefore, I can expect my next dyno run to see between 318 - 323 rwhp. Which would put me in your territory ChrisLS1bird with simular mods.

My car is mainly a daily driver so I tend not to abuse it. I have not been to the drag strip yet and it is not a big priority. But maybe someday. I am simply content with knowing I can blow the doors off the guy in the lane next to me or watch the cars in my mirror turn into dots as I floor it on the freeway

 

Well, that's how it is... compair an 02 M6 Z28 to an 02 M6 Firehawk, i'm sure they'll only be a couple hp off.

 

Look, I don't want to try to convince someone not to be happy with his car. If you're happy, that's great. That's all that's important.

If I purchase another M6 LS1 and don't make near 300rwhp (or better) stock, I'm taking it in and/or wrenching on it. 280 rwhp, for an M6, is off base for me, based on what I've seen.

Remember, we're talking M6 and not A4. The two are not the same, obviously. An A4 at 280 rwhp is OK..not great, but OK.

Hopefully the ones that aren't running 13s are running in the 12s or quicker. A 14 second 1/4 out of an LS1 is..well, that's just wrong. Now, blame it on the driver or the environment (6000 ft), fine. But an LS1 f-body is well beyond the 14s...that's tuned port induction domain. Even the LT1s, which get run upon by the LS1 at speed, frequently turn high 13 second 1/4s stock.

My opinion.

 

Yup.

And if you think that's bad, how do you think the '97 vette guys felt in '98 with the introduction of the LS1 f-body? The vette guys are the real people being screwed with.

 

They are more "well endowed" suposedly to make up for that though... right?

 

Again, this is just for discussion, based on opinions. But I think to expect or demand that "every" LS1 dyno at 300+ rwhp bone stock is unrealistic. I feel that is setting the bar a little high.

But let me clarify. From this board, for " '98 -'00 " LS1s, 280 rwhp range is typical or average. Some examples did dyno in the 300 rwhp range. These examples are what we call factory freaks. These freaks are the result of variations in factory manufacturing tolerances. As a result there is a variation on hp output. Some producing less, others producing more. Which one would you post about?

In 2001 the LS1 was delivered with the LS6 intake manifold. So '01 and '02 LS1 saw an increase in power output. I would say most '01 and 02' LS1s will dyno at around 300 rwhp. That seems typical. So to make a direct comparison of the '98 -'00 LS1s to the output of '01 -'02 LS1 is unrealistic. So far no one really has. The early LS1s simply do not product as much power as the later ones.

Now lets take a look at your rwhp ChrisLS1Bird. With free mods, a lid, and a cat-back, you are making 323 rwhp. Lids typically show gains of 10 - 15 rwhp and cat- backs typically see 10 - 15 rwhp. Throw in a handful of rwhp from free modes. If you are saying your car originally dynoed at 300 rwhp, your mods seem to be coming up on the short end.

Now, my baseline dyno was right off the street, all filters installed, all belts on. The dyno showed 282 rwhp. With a K&N FIPK, and nothing else, the car dynoed at 308 rwhp, a 26 rwhp increase. Perhaps the stock intake was the bottle neck? With the cat-back that has since been installed on my car, I would expect to see rwhp in the 320 range. These are the kind of numbers that you have ChrisLS1bird.

I believe our engines, both '98 LS1s, are off the same shelf and are producing very simular power bands.

Peace