Here is a link to a guy on the mustang forums claiming his friend has 397 rwhp with bolt-ons and 90/90. He was also saying that LS1's are capable of 385rwhp with full bolt-ons alone. Has anybody ever heard of anything like this happening before, or is something fishy going on here?

http://www.mustangforums.com/m_1519135/mpage_3/tm.htm

 

I hope your joking right ? you can get 400 + hp from bolt ons..

 

Not that i am aware of. I have never heard of anything anywhere even close to that.

 

Maybe 400+ at the flywheel. Not to the wheels. I have seen a few full bolt-on f-bodys making around 360-370rwhp. But nothin into the 380's that i have heard of. Unless its an LS2 GTO or Vette maybe.


-Blaze

 

maybe an ls6 vette...not an ls1.

 

Even 360-370 is pretty rare also though. I have enver seen more than 360 or so.

 

If it is a LS2 6 speed vette, then it is possible. I've done several C5 Z06's in the high 380 range and the LS2 seems to be right on par with them. Other then the above mentioned, it isn't happening!

 

yeah, i did not read that too well. When I consider bolt on's. I mean 90/90, cam not just basic stuff my bad..

 

Nope hes talking about an LS1 vette. Not LS6 or LS2. I think his friend is lying to him about his mods or might have bought it used and someone already installed something like an LS6 cam or LS6 heads or something. But that should be noticeable when it gets tuned, shouldnt it be?

 

The highest bolt-on LS1 Vettes I've seen are around 350rwhp. Bolt-on C5 Z06's and C6's can pass 390rwhp.

 

Have you even read the post I put up today. C6 with bolt ons

 

He's talking strictly LS1's. No LS6 or LS2's. Both of which I've seen 390's from. Nice #'s btw.

 

Yeah, but has anybody seen those kind of numbers from an 03 C5 M6?

 

An LS1 "bolt on" car (NOT an LS6) will have a real hard time achieving the 400 RWHP mark.

Mine was pretty dialed before I did the AFR H/C swap a couple of years ago and it was making around 355 RWHP....with 390 gears (so add 8-10), and with a LS6/heavily ported stock 78 mm TB (add 20 for a ported FAST 90). Come to think of it that was without an underdrive so tack on another 5...then there's the EWP so tack on another five....hell....400 is right around the corner....LOL.

I had a good air intake (Vortex Ram air), lighter aluminum flywheel, lower stat, 1.8 Crane rockers on the stock LS1 cam, Kooks 1.75 headers and a Magnaflow exhaust.

Bottom line....after reviewing the facts I have to say its possible, but highly unlikely. Keep in mind that this little academic exercise starts with a baseline that most shops claimed was very strong for the mods I had.

Good bench racing stuff....thats for sure.

Tony M.

 

No way is a bolt on LS1 gonna hit 400whp. With a cam I can see it easy, but not with full bolt ons (Headers, y pipe, catback, lid, etc..). The guy's probably lying about his mods, which seems to be common practice. Just ask me, I only have a catback and a lid :p

 

Gee not another one, don't any of you guys every do any form of reading, research and Maths???

No seriously there's two angles to this.

Firstly is dyno type, settings and standards.

There are many different types of HP which are all a resprentation of torque at a particular speed (rpm).

Car engines are rated in Bhp as in Brake horse power because a brake device is used to measure torque and derive HP.

The most popular rolling road dyno in America is a Dynojet, typically these are inertia dyno's and use a stactic wieght/drag or effectively brake. Where as more sophsticated dyno's use load bearing where the the brake or wieght affect can be increased, often via electro magnet or via water loading.

Manufactures dyno engines on an engine dyno and typically load bearing rolling road chassis dyno's such as Mustang dyno's offer more comparable numbers to manufacture numbers once you have estimated (as best as possible) drivetrain loss.

This all adds up to Dynojet chassis dyno's showing comparitively HIGH numbers.

397rwhp on a Dynojet would probably be nearer 371rwhp on a Mustang Dyno.

Then you get to the settings of the dyno, a thing called graph smoothing will dramatically affect PEAK numbers. This does exactly what it says and it smooths out all the false peaks and dips to give a smoother linier dyno graph. If graph smoothing is OFF and the dyno is jumping all over the show then a false reading 20rwhp too high could easily be acheived on such a car.

You then have a thing such as standards and correction factors. These are designed to correct for atmospheric and altitude conditions so in theory you could dyno the same engine at 10,000ft in the cold and then a day later a sea level in 90 degrees and still acheive comparable results.

Dyno's don't usually correct striaght off and will display STD numbers. Typical correction would be to SAE however this is not always done, even if the dyno graph states it has been. Also owhen these correction factors are used they are often used incorrectly. However normally they will reduce the PEAK numbers.

So you can see highly optomistic numbers can be acheived but they are in effect totally meaningless as the car won't be any faster.

Another trick is, that because HP = torque x rpm / 5252 you can fool the dyno by using the wrong gear (it does happen!!! And more often than any would like to believe). To dyno a car on a rolling road you need to use the gear which has a ratio of 1:1 (or as close as) which is 4th with M6 and 3rd for an auto (stock tranny's). If you use a gear with a different ratio you can easily see much higher or lower numbers depending on the ratio used.

As for the actual mods, well I have never heard/seen/read of a car anywhere near that HP level.

There is such a thing as diminishing returns. Which means in terms of intake/exhaust mods there is only so much HP you can achive before the heads/cam become the real restrictions. You'll notice that all bolt on's claim a HP gain over STOCK. If you already have mods then you'll probably see less gain from the mod.

There are certain mods which will always release the same amount of power regardless of current setup, these would be things like water pump, air con, power steering. This is because these items require a set amount of HP to run.

Another way to inflate dyno numbers is reducing drivetrain loss. Over inflated tyres, ultra slick wheel bearings and light weight drive/prop shafts and flywheel will all reduce the loss via the drivetrain. The engine itself won't be producing any more power but the rwhp number should be higher.

After a far does of research I really doubt a stock internal LS1 on pump fuel is able to produce much more than 400-410bhp SAE Net. This will place it firmly at 350rwhp SAE corrected on a Mustang Dyno and the same car on a Dynojet corrected to SAE should be around 375rwhp. This all tally's in well with the actual numbers produced.

So in answer to your question is 397rwhp possible from a bolt on LS1. YES it is but it is most likely a FALSE reading and totally meaningless. In the same way you could print out your bank balance but show it in Aus$ instead of US$ but forget to mention that is what you have done, because it'll make it look like you have a lot more money.

Either that or the person is a total lier and has a tame cam and/or ported heads on there also and is just trying to make it out to be something it isn't.

 

It's b.s... along with the fact it just so happens to be that every sponsor has a factory freak It's called marketing.

Has anybody ever gained 20rwhp from a fast 90/90 with stock heads/stock cam? I have a hard time believing that. And for what it's worth, oil touches rocker's. I believe that's the normal definition of boltons.

We had a shop claim they could hit 400rwhp with boltons on here a while ago, and nothing ever turned from it.. because it was bullshit. It's physically impossible to take a stock shortblock ls1 and add intake & t.b./full exhaust/underdrive/ewp/etc and make 400rwhp+.

Maybe he's talking about an ls2.

Peace,
Josh

 

The LS1 bolt-on record is right at 380 RWHP, in an F-body, lightweight almost everything, stock 10 bolt. 400 RWHP from a bolt on LS1 C5? Unheard of, but probably not *impossible*. Oh, PeweterWSsic, VERY few 01' 02' F-bods got LS6 heads, there was a thread about it awhile ago, new knowledge to me too.

 

I doubt you will see 397 rwhp from a bolt on Vette, on a Mustang dyno.

Bruce

 

Mustang dynos will dyno higher than DynoJets if the loading functions are turned off, maybe thats what happend? I'd like to see a sheet on this!