What Made the Original Yamaha Design 300HP?

[jedhead]

Rio:

jedhead:
You can get close to 300hp at the crank on an interally stock 3.0 motor. Port and polish the heads, high compression JE pistons, EH the intake, add stage 2 cams, 80mm MAF, LPM, Y-pipe and a cat-back you would be pretty close to 300hp mark. Add adjustable sprockets, and some time on FORD's supercomputer that has the SHO motor model to get the best cam timing and you may exceed the 300hp.

Bob

how the **** is that "internally stock"... shrug doh

Stage II cams and bolt-ons, such as EH intake, BBB, 80mm MAF, LPM, y-pipe, and cat-back on an other wise stock engine in good condition will get you close to 300 SAE net hp at the crankshaft (Vadim shown me dynojet sheets showing 246hp FWHP, couple that with a 15 to 17% percent loss in the driveline would be about 289-296hp at the crankshaft). To get to the 300 or more hp you would need to raise the compression with higher compression pistons or shave the heads (pistons have the advantage that you can obtain pistons that are lighter and stronger than stock thus lowering the mass of the rotating parts). Bore the engine out or start with 3.62" bore (3.2 liters). Add ported and polished heads and you can be at the 300hp mark (Vadim showed me a dynojet sheet with 256hp at the wheels which translate to 301-308hp)
I thought the 3.2 liter should have made a little more hp, but engines seem to vary in how they perform. It could be that the 3.0 had an aluminum flywheel (lower rotating mass thus more hp) and 3.2 had a quaife and a stock flywheel (higher rotating mass).

I believe Ted Breaux's SHO, some time in the past, had adjustable cam sprockets and cams made my Logicams. Someone modeled his engine with the custom cams on Ford's engine model and came up with the best cam timing. His SHO was one of the most powerful SHO around for a while.


Bob

<small>[ June 17, 2003, 01:32 AM: Message edited by: jedhead ]</small>

 

[mkoronowski]

speedy91:
I hate this myth.

Don't you think that if the original Yamaha had 300hp and Ford detuned it, that the aftermarket would have a simple way to back to 300hp. I know there are some very talented and knowledgeable people out there that work on and love this engine so they would have figured this out almost 15 years later.
Rant over
Eric

I don't think DOHC 5 valve heads are in production by anyone. Otherwise, I would agree.

 

[BlackOnBlackATX]

mkoronowski:

speedy91:
I hate this myth.

Don't you think that if the original Yamaha had 300hp and Ford detuned it, that the aftermarket would have a simple way to back to 300hp. I know there are some very talented and knowledgeable people out there that work on and love this engine so they would have figured this out almost 15 years later.
Rant over
Eric

I don't think DOHC 5 valve heads are in production by anyone. Otherwise, I would agree.

doesnt ferrari or lamborghini or one of them high end pasta rocket companies have something like that though? could have sworn i read about that a while back. probably single cam though when i think about it...

 

[TheNoachSHO]

Volkwagen and AUDI have them...Look at the 1.8T engines! 20 Valve. Ferrari was the first to use them.

It's usually as I know it to be 3 intake and 2 exaust.

 

[fendermb4]

I have a NA 1998 Volvo S70:
4 cylinders
2 cams
20 valves

 

[ALWyzBrknSHO]

just my 2 cents here, i was talkin to a guy about my car and he knew some state troopers who had some SHO's and that they were testin some of them up to 12,500 Revs also...someone else also mentioned 12,500RPM, coincidence? Who knows, Way I look at it, it's a. a yamaha motor which means it's gonna have some serious revs b. it possibly might have actually been a boat motor (anyone checked any high performance boats for one of our motors?) c. everyone heres this and that, so some of it must be true, I personally believe it's possible, it's not easy work, but if you look at all the specs on the motor it's more than possible to get 100HP/L

 

[rendyx]

ALWyzBrknSHO:
just my 2 cents here, i was talkin to a guy about my car and he knew some state troopers who had some SHO's and that they were testin some of them up to 12,500 Revs also...someone else also mentioned 12,500RPM, coincidence? Who knows, Way I look at it, it's a. a yamaha motor which means it's gonna have some serious revs b. it possibly might have actually been a boat motor (anyone checked any high performance boats for one of our motors?) c. everyone heres this and that, so some of it must be true, I personally believe it's possible, it's not easy work, but if you look at all the specs on the motor it's more than possible to get 100HP/L

I have heard the SHO motor can rev to 12.5k - only once. And keep this in mind too: if we gobble up rod bearings hitting 8k at the most, imagine what might happen then at higher RPMs...

I have a few opinions on the "300HP SHO." First, it may have been a small S/C setup. Consider how the Chilton's tells us to change our S/C fluid. Cost would easily destroy this idea. Second, I'm sure there were several prototype designs, as with any product in development. Maybe one design had a larger displacement, who knows. Third, and probably most likely true, is that Ford originally wanted 300hp out of the Vulcan, with Yamaha heads. That couldn't be done, but could be the source of that number.

 

[79pace]

One thing no one has mentioned here is that most of the Japanese automakers still rate horse power the way we use to in the 70's therefore they usually have a higher number than what is actually in the vehicle once all the smog and accessories are hooked up. It wouldnt take much to make a 220 horse motor show 300 horse on a dyno. Put better exhaust on it and a performance chip and run it in a nice cool dyno room and I bet your close using the japanese method of dyno testing.

 

[ALWyzBrknSHO]

on most hi performance japanese cars (evo, sti, skyline, etc) they rate them all at 276HP just cause of this goverment BS they have, even though we know they have more than that, so i dont know about the testing theory

 

[SHODWN]

SuperHO there is a video of this that was shown at certain dealerships to techs as well.

SuperHo has writen fact

All other things are fiction the have been written here

 

[ALWyzBrknSHO]

anyway that we can see this vid or documentation that you speak of?

 

[Dr.Evil]

crank the displacement up to 3.8 like the GL motors, keep the 73hp/L rating with the same comp ratio, cams, maybe a larger bore intake for the increased flow, you have close to 300hp stock. there is no replacement for displacement!

<small>[ June 20, 2003, 01:30 AM: Message edited by: Dr.Evil ]</small>

 

[philw349]

Just pay money for mods. Money = horsepower (at the speed of light squared). Regardless of the truth of the rumor, there is no button to push that will give you 300HP. HP costs money. How much do you wanna spend?

 

[Groo]

I hate this myth.

Don't you think that if the original Yamaha had 300hp and Ford detuned it, that the aftermarket would have a simple way to back to 300hp. I know there are some very talented and knowledgeable people out there that work on and love this engine so they would have figured this out almost 15 years later.

It doesn't seem like a myth to me. If Ford really initially wanted to drop this motor into a high performance car, the price probably would have been high performance as well. This would have allowed a potential motor to be built to very tight specs, with expensive, high quality parts.

I think people on this thread have shown, without a doubt, that if you throw enough money into the SHO motor, you can get 300hp. And while Yamaha may not have taken the exact same route as the SHO Shop, I think their engineers could have done it too. Of course, this motor would have to have been very expensive to build.

In order to cut costs, and to fit it into a Taurus, that the motor was probably reengineered, and we have the car we have today.

 

[yamahaSHO]

philw349:
there is no button to push that will give you 300HP.

Sure there is, it is called a nitrous button thumb

 

[speedy91]

I completely agree that you can get 300hp out of the Yamaha. Money can get you a long ways.

My point is that a mass production engine is not going to be developed to that level. The SHO is a very efficient engine from the factory, everyone agrees on that, but that means that there is less room for improvement. Why do you think our mods do not yield the big results that they do on other engines? The SHO engine is much closer to its maximum potential without boring and aggressive and expensive mods.

 

[SHODWN]

it sure can, but when you put more money in the car than the car is worth, when do you say enough is enough.