Pistons

Hi Guys

I am a new 460 owner and am looking for a set of pistons that will give a compression ratio of 8:1 to 8.5:1

Bore 4.40
Stroke 4.5
Rod 6.8
heads 74cc Dove c
zero deck height

Is there a set of pistons off the shelve I can buy or will I need to order a custom set.

Thanks

Kev

Yep, i am building a it with a gt55 turbo running on methanol, is it possible to run the 6.605 rod instead of the 6.8.
i figure this would give me more piston choice

You can also use a .0120 head gsk.

What is the thickest head gasket you can get and would use on a turbo motor without going to copper or is copper my best choice.

if your building new and dont have a crank,rods or pistons. maybe a smaller ci. engine will do the job you can get alot of hp when put pressure to it ive seen some small ci. make 1000hp easy how much power are u looking for

As much as I can pump out of a GT55 turbo on methanol.

If I use a 6.7 rod with a 1.245 pin height piston this would bring the piston down the bore 100thou, can this be done?

4117kev wrote:As much as I can pump out of a GT55 turbo on methanol.

If I use a 6.7 rod with a 1.245 pin height piston this would bring the piston down the bore 100thou, can this be done?

Yes, this is the most practical way to set up a low compression methanol burning engine. A lot of force-fed methanol drag racing engines (and nitro burning engnies) are built this way specifically and for the same reason you are asking (compession ratio). Quench is not critical in a methanol burning engine and much less so in a blown (turbulent A/F mixture) methanol burning engine.

That being said, MeOH can handle more compression ratio than 8.5:1 but there's not necessarily anything wrong with that compression ratio. Frankly, for structural integrity I'd step away from the 4.50 stroke crankshaft and go with a forged 4.30....but if you must stick with a forged 4.50 then turocharged on alcohol is your best bet.

Diamond makes 32cc-36cc dished pistons that would meet your compression ratio needs when run at .100" in the hole. 0.040" overbore is not a common bore size but rings are out there so if you can use that bore then you will be maintaining better cylinder wall thickness than gong to 0.060"overbore.

Paul

4117kev wrote:Yep, i am building a it with a gt55 turbo running on methanol, is it possible to run the 6.605 rod instead of the 6.8.
i figure this would give me more piston choice

X2

With forced induction and high octane fuel such as alcohol ... simply use a 6.700" rod instead of the 6.800" rod and run the piston .100" down the hole.

Thanks Guys

We already had the motor and have been running it in N/a form for the past few years and it was showing 800rwhp at the track, not bad for an old cast iron headed truck motor.

So the plan is we already have the new 4.5 crank sitting to replace the current cast item and now some new rods & pistons and we will see what it does with the turbo attached to the front of it.

Being new to 460's myself I am sure this won't be the last time I come here for advice.

Thanks

Kev

4117kev wrote:Thanks Guys

We already had the motor and have been running it in N/a form for the past few years and it was showing 800rwhp at the track, not bad for an old cast iron headed truck motor.

So the plan is we already have the new 4.5 crank sitting to replace the current cast item and now some new rods & pistons and we will see what it does with the turbo attached to the front of it.

Being new to 460's myself I am sure this won't be the last time I come here for advice.

Thanks

Kev

new and the past few years and 800 rwhp . OK

800 RWHP with Dove c's N/A..................... I'm impressed good job.............

You may want to look at the cheap Pro Comp aluminum heads for what your doing. May fill the bill if your doing it on a tight budget.