Any experience with the Cola Ultra-Lite "U" crankshaft? Building a splayed/blown 355 and aiming for 700-1000hp. Just looking for feedback on this crank. Also, anybody know where they sell it at a reasonable price? thanks

 

Cola has been thru a bankruptcy and then re opened under and similar but different name.

They would be the guys to ask but I would imagine that those cranks could hold 1000hp.

Any 32lbs crank is not going to be reasonable. The Scat Ultralight cranks for around $1000 are about as reasonable of a lightweight crank as you can get.

Bret

 

Thanks Bret. By reasonable I basically meant where is the best and cheapest place to get one of these cranks.

 

The last Cola Ultralight we bought was 1495, But we checked and due to the backruptcy our Vendor no longer carries them. I suspect this will be a common problem. So you may have to look around some to find one.

You can also buy one from Hank the Crank or Callies just add a hundred to the cost and they are just as good if not better. And the cranks will hold the horsepower your looking for but oiling is critical.

Stroker is right about the Scat crank for the money its about as good as your going to get.

 

How reliable are the Scat Ultralight cranks? What is their hp rating? I've never been to fond of Scat.

 

Their high end stuff is nice. The forging might be made in another country but the machine work is done here. They spec out nicely when I check them.

The Ultralight will handle what you are looking at. RPM and bad machining are what break cranks. The parts on top of them mean a ton too. The more mass on top of a crank the more stress too. Lightweight parts help accelleration a ton, but they also cost more $.

This thread gets into the forces on cranks. http://web.camaross.com/forums/showt...0&pagenumber=1

With what you are looking to do 1000hp in a race car is going to need one bad rod and piston. How are you getting there?

Bret

 

Stroker is dead on

Above 800hp you are going to need a billet rod. So there will be a big jump in cost at this point.

You want a better piston too.

Go as light as you can and as strong as you can.

 

700-1000 hp? that's a big gap that puts an engine of this size at two different ends of the spectrum.

cola, htc, lae and others make good pendelum undercut, lightweight cranks that will do the job. i wouldn't be too quick in purchasing the lightest piston you can get. primary concern here should be top ring placement, along with wristpin placement. that usually dictates a slightly heavier piston and so be it, you'll never need to see more than 7k to reach your goal.

are you building this engine yourself or do you have a builder in mind?

JB

 

Yeah Jeff's right, but I would opt for some lightening options after you have the piston worked out right. Lord knows that a 325g 2bbl 400hp piston is not going to work on a 1000hp motor.

Bret

 

Thanks a million guys. I really appreciate the info.

Bret,
How much does the Ultralight go for? Setup will initially be a sollid roller 355, d-1, th400, gtp lt4 heads, and liquid-cooled. Thereafter, I plan on stepping up to a big turbo.

TIMEBANDIT
I was looking into some Arrow billet rods. The mustang guys are using them without problems.

Jeff Belloma
I was gonna have GTP build the engine.

As far as pistons go, what do u all recommend?

 

The Scat goes for $1000-$1200.

Those are some nice rods, Arrow makes some good stuff.

GTP should be able to come up with the right piston for you, if they can't then they shouldn't be throwing that puppy together.'

With all that boost you'll move the top ring land down the piston so it doesn't get to hot.

How big does Craig want to make your heads? I know Jeff has a nice set of LT4's on his motor, but he's NA and not pushing a ton of boost thru them. Craig can port one hell of a head, I hope he's the guy that is doing it for you and that he doesn't do his standard small port for that kind of setup.

Bret

 

just a few points here, and of course you are free to take any advice or leave it...

are you set on building a 355? since you're talking about a fresh slate motor, why not just go 383?

we've done similar 355 builds and just to give you an idea... here is a semi-breakdown of one one of these motors in particular:

gm sportsman block fully machined, out of the box brodix track 1 heads, accel superram intake, twin turbonetics turbos & deltagates wastegates, comp hydraulic roller, hks intercooler, 8.5:1 static compression, accel dfi, and other parts to handle the power. this has been maybe 8 years so turbo technology has come a long way. i've done a few strokers since then but this was the last 355 i worked with... most opt out for a stroker...

at 12 psi of boost and pump gas we were seeing close to (i don't remember the exact numbers) 770 hp and 830 lb ft of torque. a bump to 18 psi was putting us at well over 1000 hp but no more pump gas.
keep in mind that this was what i call a piece together motor. the machine work was spot on but other than that we simply sat down and ordered parts, when they came we bolted everything together and tuned the snot out of it. no development work, no porting, just a low-cost approach to putting an engine together for this particular customer. back to that example, you could easily see another 30-50 hp 50-70 lbs ft from a 383 in the same configuration. that torque curve is where it's at with these motors so why not take advantage of the extra stroke? at least that's my take on it.

so, you shouldn't need a solid roller to reach this goal. in most of the force inducted 4th gen setups i've seen, setting periodic lash would be more headache than most would really like to deal with. and its just not necessary.

for pistons, i'll reccomend cp, je and bme. i have every piston i use in my competition motors thoroughly tested by a local gentlemen who owns a very nice cmm and does mucho aerospace inspection work. of all the brands i've used or tested, these three seem to have the best ring groove concentricity, surface finish and are just very precision pistons. not to say that others don't make good pistons, just that i will choose from one of these three before looking elsewhere.
call them up, let them know exactly what you are planning to do and let them guide you on any weight reduction options.

Good luck.

JB