JoeZ

What is the best valve setup for a v8 to get very high revs? I'm talking around 10,000rpm. A buddy and I were thinking of taking a 454 and destroking it so it is much much less in displacement, but then we were wondering if the vavles could keep up, and if it would have to be a DOHC engine to be able to do it...

Fevre

10,000 rpm's! :eek:

I would guess you need a mech roller cam and some serious springs along with great push rods and rockers. You are talking some high $ stuff to get to 10,000 rpm's. Oh ya you will need a cam with some major duration.

Sounds like fun though. :)

Lt1er

Why do you want to spend thousands of dollars on something that won't last more than 1/4 mile runs between tear downs?

zwede

Top fuel dragsters usually shift at 9500 rpm, so I guess obtain a used dragster engine. It will surely have low mileage, only driven on sundays. How can you loose?

BB wowbagger

A freind of mine drove a procomp BB vette.The shiftlight lit up at 10200 rpm..It was a complete monster,16-1 comp ratio(what he told me anyway).But when he blew 4 trannys(ST-10) in one weekend he gave up,dont blame him :cheers: :cheers:

MikeC

Nascar teams don't even go that high! They don't for a reason, and believe me that not a cost issue, its a durability issue. The engine will not last that long.

JoeZ

It's actucally a project a friend was curious about...for road couse / auto X driving. I was wondering, is it possible to "destroke" an engine? That could help RPM due to shorter travel distance of the piston. I'd think this to be better with a DOHC like maybe a cadillac engine.

Twin_Turbo

stroke & bottom end strenght and balance isn't the only problem w/ high revs, valvetrain, ignitoon all comes into play.

BSeery

good luck slinging the weight of big block components to 10,000 RPM.

You would be much better off starting with a 4 cylinder or a 283 at the largest.

JoeZ

http://cgi.ebay.com/ebaymotors/ws/eB...category=33615

V8 ^

How would you build a 4cyl to do that? If it is in a 4cyl (which neither of us though of before) that would be perfect as it can fit into a smaller car. He figures only about 500hp will be needed.

Can anyone specify a good website for building a 4cyl like this? Or maybe a good block to start from?

BSeery

Some of the Supra's with turbos are putting out around 800+ HP, and I would bet a well built 4 banger turbo with NOS could do around 400HP - 500HP. But we are talking PROFESSIONALY built motors here. Check around the Honda and Supra forums for info on those motors.
It's easier to get high RPM form small motors as there is less weight to be spun. If you were to spin a 454 crank to 10,000 RPM it would take a long time to get there and would need a lot of power to do it.
Now picture a little light weight 4 cylinder crank, and how much easier it would be to turn that to high RPM.

Shot for middle ground.

Get into the 6 cylinder Buick motors. They were the FASTEST motors at Indy before they all went to common motors under the new rules. A 4.1 or even a 3.8 liter turbocharged Buick motor can lay some serious horsepower. Even in the Indy cars they only spun the v6's to around 8000 RPM though.

JoeZ

Look at the Honda S2000. It redlines at 9000 RPM, but can rev higher...and this is stock. While it only makes 240hp, this is what I'm talking about. Since that is stock, wouldn't you think it can rev higher with certain modifications, if even only 1000rpm higher?

Twin_Turbo

There are 4 bangers w/ more than that, didn't the Lingenfelter built opel ecotect 4 banger put out over 1300Hp ?

garagedweller2

Why is it necessary to rev that high for Auto-X and Road Racing?

JoeZ

More range, more fun.

aharte

You said above that you think 500 hp would be fine. A BB can do that easily without revving high at all. Even a small block can do that with some work. There's no reason to rev high if you can get the power you want without it. The only difference will be a louder exhaust note :). Shift points etc should be changed with gearing. By the way, shifting at 10000 rpm would be "interesting" on your clutch with a normal flywheel.

An S2000 engine is very highly tuned stock. Even with a turbo setup, people manage only about 350 whp on racing gas. Its too small to make serious power (although that is remarkable for 2L).

Here's more information on the S2000 engine if you're still interested:
http://www.s2000.org/articles/f20carticle.pdf

OatBoy

except they run sometimes as much as 6000 stalls and their idle sounds like a train

JoeZ

Setting up a high reving engine that only makes 500hp was what I was saying....not saying that 500hp was all that was needed.

I'll go check out those import tuners ( :U ) and see how high they can go on honda engines or other.

garagedweller2

I remember in the other cars forum "RSX CAN do 12,500 rpm" and there was a pic of piston parts in the intake. :bb :lol: :lolg:

Larry B.

Winston Cup race cars only run to around 9400 but just for short periods or they break. These guys are the Gurus of stock block V-8's. They spend Mega bucks on research and use only the latest technology. Smaller engines run faster but have no low end torque. That'y why you see Indy cars stall leaving the pits. Some years ago some of the indy car engines used 180 deg. crankshafts so two cylinders fired simultaneously. These engines are much smaller displacement.. Maybe a two cycle V-8 would run at higher RPM's There are some single cylinder model airplane engines that are cpable of 32,000.