BLKWS.6

Wow. Everyone, All of you who have late model LS1's who dyno at 300rwhp really only have 280 rwhp and thats dead on for being rated at 320 and you ARE NOT REALLY UNDERRATED. I AGREE WITH 300BHP its all a Hoax by GM insiders trying to get you to buy the LS1's.

300bhp/ton

I don't know what a 96 cobra makes. 99-04 GT is generally right around 225rwhp to 235rwhp STOCK on a Mustang dyno.

BLKWS.6

Wow. Everyone, All of you who have late model LS1's who dyno at 300rwhp really only have 280 rwhp and thats dead on for being rated at 320 and you ARE NOT REALLY UNDERRATED. I AGREE WITH 300BHP.

BLKWS.6

On a dynojet most 96-98 cobras made 255ish which is about 235ish on a mustang dyno.

300bhp/ton

how old are you???


How can this be explained so you might grasp it.

280-300rwhp Mustang dyno is = to 300-320rwhp dynojet dyno.

Or at least thereabouts.

The cars that generally dyno the lowest are AUTOMATICS, these have a greater drivetrain loss, although the engine will still be producing the SAME bhp.

Other odd ball numbers are generally from 'other' types of dyno like Dyno dynamics or Rotosound. Or are mis-calibrated dynos or mis used. If a car is dyno'd in the wrong gear, or the WRONG correction values are added very different numbers can be produced.

Thing about it even a 10% error in reading can have a LARGE effect on the overall result.

300bhp/ton

what where they factory rated at?

And remember a rolling road dyno has a lot of other factors that can effect the outcome, the engine may well still be producing a very different number.

A rolling road dyno is a TOOL for tuning, NOT a MEASURE. The results are too inaccurate. as the reading is too far away from the source.

BLKWS.6

They were rated at 305bhp

300bhp/ton

then there must be some other factor involved.

Honestly I really love the Mustang, esp the Notch and the new GT. If I had the money I would have bought a new GT.

BUT - the truth is they are not underatted. They are however 'undertuned' and have lots more potential.

BLKWS.6

BHP, how can you argue that an LS1 that gets 300rwhp on a dynojet is underrated when its rated at 320 but a 05 GT gets 280 rwhp on the SAME type of dyno and is rated the SAME 20bhp more at 300 and it is NOT underrated??? This eludes me greatly... And no, the 96-98 cobra was VERY overrated. The other mustangs were pretty accurate in their ratings. the 93 Cobra may have been slightly underrated though. but other than those 3 exceptions ford keeps it pretty level. So did GM until the LT1 (slight underrating) and the LS1 (underrated).,

300bhp/ton

the most liekly time 300rwhp on a dyno jet would occur would be for an auto.

There's basically 4 alterntives (just using the two most common rolling road dyno's)

Auto - dynojet
Auto - Mustang dyno
Manual - dynojet
Manula - Mustang dyno

Know a Manual on a mustang will likely dyno very simlar to an auto on a dynojet. But if you then assumed the auto has a greater drivetrain loss it would appear to be producing more power at the einge. This just isn't the case. So it's safe to 'regarde' the auto/dynojet result.

If I'm explaning it very well I apologise. I know what I mean, it's just not easy to describe in a few words on an internet forum.

From what I've seen/read/head about:

Automatic Fbody will dyno ~280rwhp on a Mustang dyno and ~300rwhp on a dyno jet. Due to the LARGER drivetrain loss the 'estimated' engine output is ~345bhp

Manual Fbody will typically dyno ~300rwhp on a Mustang dyno and ~320rwhp on a dyno jet.

From what I've for the s197 GT, they will dyno ~260rwhp on a Mustang dyno and ~280rwhp on a dynojet dyno.

ALL numbers should be subject to a +- factor of 10rwhp, this allows for operator error and manufacturing tolorances.

The only time the numbers from the GT and the Fbody are close is when you use the LOWEST for the Fbody and the HIGHEST for the GT, each figure being generated by different types of dyno.

BLKWS.6

I agree, the LS1 has more hp than the 3v 4.6 About 20-30hp from all you are telling me and they were rated 20bhp different, wouldnt that stand to reason then that they are both underrated (granted the LS1 moreso)?

300bhp/ton

ok. This is a rather poor 'guesstimate' chart for working out engine BHP from a dyno result. It is generlising so don't take it too literal. But the basic idea is correct to the best of my knowledge. It is for a Manual transimission ans assuming 12% loss + 10bhp. All you need to know is what type of dyno the the result is from. REMEMBER this is MANUAL transmission only.

LS1-450

iTrader: (33)

From the shape of the curves two things are clear. First, the car starts losing power early. Second, there is a lot of room for tuning & aftermarket improvement. Therefore, both CamaroSS & Unit123 are correct in their statements. The stock version is weak & modded 05 GT's can be fast cars. There's a lot of room left there by Ford for the aftermarket guys. It almost looks intentional.

Redneck Z

iTrader: (3)

Thats 20-30rwhp, so close to 40 flywheel hp. Who cares what the LS1 was rated at, we all know it isn't accurate. The factory rating for the 3v is accurate, however. The LS1's should have been rated at more like 350 hp. If you guys want to talk about fastest stock cars. The 3v might have run 13.15, but the LS1 has run 12.7. Thats almost half a second quicker, not too mention it was probably at 107ish mph vs. the 99mph of the mustang. I don't see where the argument is. And no, the 3v's don't run as good as the mach's.

unit213

The owner of that car has a '02 Mustang GT that runs 7.0 @ 207mph.
Still doubt a low 12? Come on bro...

It has a fairly extensive mod list, but nothing crazy.
-stock short block
- nitrous
- ported heads (for research & test purposes)
- exhaust
- a few other minor things such as CAI

BLKWS.6

I see what you are saying 300BHP about the difference in Dyno, but i still think the 05 GT was a tad underrated. Call it a differenceof opinion if you are so inclined.

Ell Ess Won

I think the new Mustang is God awful in the looks department. There's nothing streamlined about it. *puke*

Bitemark46

Bro, stick to pushrods cause you dont know squat when it comes to modulars. 96-98 4v's were not over or under rated. 305bhp * .85 = 259.25 rwhp or there abouts. The only over rating was the issue with the 99 DOHC's. Which shortly after had "the fix" and then thereafter put down the advertised power (320fwhp or 272ishrwhp). I have never and I repeat never seen a stock 96-98 cobra dyno less than 249rwhp on a type of dyno. And even then it had IMRC issues. I've been involed in the modular motors since 98. For a manual tranny in the cobras (T-45) standard drivetrain loss is about 15%. All the other mod motors (96-03 SOHC, 01 DOHC, and the new 05 SOHC are pretty much on the money with advertised fwhp.

Now with the LS1's I will say that they are under rated from the factory. Lucky bastids. -Mark

LS1-450

iTrader: (33)

No, I don't & didn't doubt the low 12's @ all. What was & is in question is the stock 05's ability to run low 13's. I said your friends mod's. should be posted to make it clear that the low 12's mentioned were not in reference to a stock 05.

99camarosupersport

iTrader: (6)