I will use my old engine.

4" Crower, Carillo, Trw pistons. (468cui)
310cc Canfield. 252/262@050 660/666 lift roller cam. 10.4 compression. Pump gas.

Can i use 4-6psi of boost on this engine.

EFI of course.

Size of turbo for a 800hp limit? Injectors is 640cc so they couldnt deliver more fuel. Using 1 Aeromotive A1000 pump also. having a A1000 regulator with boost inlet.

Can it run with this high compression on low boost?

What about lowering comp ratio with 0.050 gasket insteed of 0.032 gasket? Will it detonate because of larger quench?

Will be using Direct fire ignition. One spool per cylinder.

Recomends on wastegates?

This is a must, cant put it away now. So help me build it right.

Dont want to change pistons. Will change them next year. (block pistons for a 536cui. 4.600 bore)

To optimize your turbo you would need to change the camshaft too. Id wait till you could do it right with a cam and a piston change.

You might want to look into a small supercharger for now.

Want to build it up and sort bugs out. Then rebuild internals with new block and make some boost.

And a turbo camshaft look like?

high compression and boost and pump gas is a recipe for disaster. I have seen many customers try this and 99.99999% of the time this is the outcome http://www.chevelles.com/showroom/bigboom1.jpg

I would suggest lowering the C/R now or plan on running C16 or an equivalent fuel.

My plan would be this:
8.5 C/R
65 degrees or less valve overlap
T-88 turbo
45mm wastegate

Even with a low 4-6psi setting?

Should be running AG108 octane with boost. Pump gas when non-racing (non boost)

Why Could a Procharger be able to add some boost, and turbos wont, Heat?

I not saying it cant be done. It will be alot of trial and error with very little room for error. If you try it with that high of compression start off with high octane fuel so you have some detonation resistance while you get the fuel and timing/boost retard set.
Also get the biggest wastegate you can find because to run that low of boost you will need to bypass a bunch of exhaust, you may even need two wastegates.
FWIW a engine with a low C/R and high boost will make much more HP than a high C/R engine and low boost.

Possibly a blow through carb set up to run methenol. The methenol evap in the manifold will cool the charge, coupled with it's high octane and you may get away with it.

Originally posted by godsend:

And a turbo camshaft look like? I dont think that you will be able to sort the combo out correctly with that high of static compression, and a cam designed for a normally aspirated engine.
Here is why...

A turbocharger is driven from exhaust gasses. It isnt unusual for exhaust backpressures to be double the boost you are generating. A cam designed for a normally aspirated engine will have quite a bit of valve overlap to allow exhaust scavenging of the cylinder. Now if you add a turbo generating say 4-6 pounds of boost you can generate 8-12 lbs of exhaust backpressure that will backflow into your cylinder during overlap. This is bad because it will increase cylinder temps, and also dilute the intake charge. This will make the engine more prone to detonation. Add the fact that your static compression ratio is really too high for a turbo and I think you will really be dissapointed for the money you will spend.

Camshaft and Head gaskets can be changed. But i dont want to change pistons when i have a year left on them. And will go bigger next year.

I thought Turbo/n20/Blower cams looked the same. Not exactly, but lot alike.

So a blower (vortech,paxton,Ati) will not generate that much backpressueres because of free flowing exhaust?

Godsend, try these guys, www.youngsperformance.com (http://www.youngsperformance.com)
They know turbos. They build some of the most awsome rides I've ever seen. Be prepared to scrap the 500+ cubic inch turbo motor and build a smaller cid BBC, like the one you have now. They like to keep them on the small side but trust me they will get you more than enough power. I recenty saw a 65 chevy II with one of their motors. A 360 cid sbc with a single 101 mm turbo and EFI, the engine dynoed at 1600 HP. On the second pass he almost wrecked the car, scared the guy so bad he loaded it on the trailer and took it home.

I thought Turbo/n20/Blower cams looked the same. Not exactly, but lot alike.
Of the three power adders...I think your motor is best suited for a small shot of nitrous. Look at the valve timing on the cams.. Turbo cams are different.

So a blower (vortech,paxton,Ati) will not generate that much backpressueres because of free flowing exhaust?
A belt driven blower will not generate any backpressure. They do also add some heat to the intake charge and generally require a lower static compression ratio like a turbocharged application.

Using a 2x150shot of nitrous now...

Looks like a will have to build my setup and dont mount it before my new block/piston/cam change is over and im a proud owner of a 536 cui motor.

I thought i could test it out and start mapping and tweak 2005 and go fast 2006.

Looked @ ATI and Procharger units. More expensive than a twin turbo setup are. Twin HX50 with dual 60mm wastes and 50mm popups will be around 1750$ here (new)

And a ATi unit will be around 4000$ here with freight and taxes.

I Decided to buy 070 JE pistons with 3cc dish.

That will yield 8.72 Compression with 0.032 head gasket and 0.035 quench. (detonation safe)

So is the HX50 setup i get very cheap a good way to go?

I dont want over 1000hp. I will run on pump gas. Cam choice? Must be solid roller. Get allergic with other stuff ,)

godsend,

I believe the HX50 turbo is a Holset turbo intended for low RPM diesel engines (~2100 RPM). They will probably not be a great match for a 6000 RPM gas engine.

Yes thats correct. We use them alot over here in fast 2.1l Volvo apps. With 700hp+ 9000rpm+

I dont know what RPM my engine will spin them to. Because i use twin and have only 7.6l

Another car here uses them and have taken out 2000hp+

I don't know if what you've got in mind is even possible. A local here has a 433" BB with a single big turbo that makes about 2000 H.P. at only 433 inches. It is very fast and just last weekend trashed the built up Powerglide behind it. So far it's only run to the eighth mile point and ran 5.01 with the boost at about 8 pounds. I think most of the very fast turbos use static compression ratios around 7.5-1 so they can adjust the boost as needed.

Static under 8 wouldnt that give me a lazy car of the line?

I dont want transbrake or antilag. Will use n20 and idle start.

N20 will be shut down 2psi under max boost with electrics.

I want boost to be controlled and applied over 4500rpm only. That gives me free hand on N20 starting line adjustments that i need to have at streetrace. Will be using a NPC box this year but at next summer will be testing Traction control EMS system.

Hi godsend, This car leaves with the engine at about 4-5000 RPM and it is anything but lazy. I may ask about his static compression at the next test and tune. When you hear it spool up you know all hell is about to break loose.

Thanks ;)

Aiming for 1000hp and streetable with little more harmony.

Have you designed any turbo cams?

I hate to bring this up and I might get flamed for it but who knows. Over the last couple of years a lot of the import stuff has started leaning towards static compression ratios around 10.0-10.30. The idea was that they needed the compression to spool the monster turbos they put on teeny little 2.0 L motors. And as it turned out it was doable but only w/ extremely accurate engine management. And I don't mean a mail order my-buddy-from-the-internet-runs-almost-the-same-combo-and-he-hasn't-blown-up-yet tune. Get yourself a DFI and someone w/ a ton of experience and plan on spending a lot of hours crunching numbers. Now I'm not sure that a 500 inch motor would have any trouble spooling any turbo out there but it's definitely food for thought. And those import guys sure have things backwards but even a blind squirrel finds a nut now and then.

As i said before. Im familar with EFI. I can map it.

I will have the latest EFI tech i can afford in it. And know what it means in numbers.

So the projects starts. Engine will be dismounted from my car and next week my engine guy will disasseble it. We have to check my bores if i can go 060 or must bore it out more.

Camshaft, any new things for a roller motor seeing 7500rpm max? Stall speed isnt an issue. Will be using N20 for it.

Will be using JE pistons for a 8.76 CR

Who makes cams?

Call "Crower" In California, USA... 619-422-1191
Ask for Dave.

Question. Will he grind a cam for me with me providing specs.

Or is he familar with turbo/streetdriven bigblock apps so he can grind with own specs?

So. im going with an Microtech LT8S ECU with broadband support and 45psi mapsensor.

I will be using an 8" MSD cranktrigger and MSD DIS4 Ignition Module and 4 Ford CDI spools. Will be running Wastespark for economy.

Twin 50 or 60mm Billet WG, Twin 50mm Billet made dumps. 2" stainless headers with puls-split will be made.

I keep this thread updated with questions and before februari has ended results from bench racing ,)

Originally posted by godsend:
Question. Will he grind a cam for me with me providing specs.

Or is he familar with turbo/streetdriven bigblock apps so he can grind with own specs? They will grind what you want or they can help you. It is certainly going to be a challenge to design a cam to mix nitrous with turbocharging, as both have their own unique properties.. I would call and see what they recommend. They are into all forms of racing so they might have an insight into your combination.
Let us know what they say..

Ill also add that most performance turbo cams are ground on a wide LSA.