I looked into building a motor not long ago, and it seems that you could build a 5.7/6.0 that would put more to the wheels than a Radix system.

Or, is this a pipe dream?

Anyone ever priced out a 400-450rwhp aluminum motor? Could that be done with heads/cam?

 

For the price of the Radix supercharger you could definitely build a 400-450 hp engine. The only benefits from a supercharger in my opinion is driveability and emissions compliance. Just the heads and cam will cost right around $2500 and you could probably find a 5.7/6.0 for around a $1000-$1500. Figure in a couple hundred for bolts and gaskets and you're still under the $5000+ for the Radix. Keeping in mind that this would be if you do the work yourself.

 

You could actually put together a motor for N/A that later on with a simple head swap/recondition could be a FI motor.

If you put together a 5.7L with 2cc dished pistons, stock .053 GM head gaskets, 5.3L heads with a 60cc chamber you'll be at ~11:1cr. Then in the future if you wanted to throw a supercharger on it you could get a set of 73cc heads and a thicker .060 GM gasket and be at ~9.4:1cr. That motor could take 10psi intercooled on pump gas all day long and probably make in the range of 570rwhp.

The RADIX setup really looks like a great setup for a 4.8/5.3L though. I don't know how well it would keep up with a bigger motor. I know a D1SC Procharger would keep up though. I emailed MagnaCharger to see but, still haven't gotten a response.

If you went with an aluminum motor one big benefit is that you'll be getting rid of almost 100lbs off the front end.

Hmmmm....That's a hard decision.

John

 

Would I need to do anything internally to the 5.7? Guess that my 212/218 isn't going to be of much use if I do this, but boy am I glad that I got the 918s! LOL

So, get an aluminum longblock, use my waterpump/intake/accessories, get a h/c package and call it a day? I'm assuming that the truck headers will bolt up to the aluminum block?

I really think that the weight loss will help a lot more than the extra 15 cubes...look at FarmTruck, for example!

A 400rwhp motor in a truck would trap in the 105-110 range I'm sure! This is looking better and better the more I think about it!

 

Yeah, you could get a stock longblock. I was talking about putting one together with upgraded parts throughout in case you wanted to go FI later but, a stock one is fine for NA. Just upgrade the rod bolts and maybe throw some head studs in for good measure.(If you ever want to spray)

Everything from your motor will swap over to the aluminum block. The headers will also fit fine. I think one of the accessory bolt holes will be missing but, I don't think that bolt being missing has ever caused any trouble.

105mph should be cake especially if you throw a stall converter into the mix.

John

 

Yes,you could build a NA engine that would make the same horsepower as a Radix but to make the low end torque you would need to have maximum displacement 430+ cubic inches.Or you could spray a 150 shot on a bolt-on motor.The big inch motor would be very expensive and give poor fuel economy.The sprayed motor would only give you the performance when you are actually spraying.If you are working on a budget spraying a bolt-ons motor a 150 shot or less is the way to go.

 

John, I thought that it was the other way around! I thought that the hole was missing to put the car accessories on the iron block, but that all of the mounting holes for the truck accessories were already on the aluminum block?

 

Yeah, I think you're right about the accessory holes.

whitt1 - What you're saying about not equaling the torque of the radix with a 5.7L is absolutely true.

It's kinda a toss up which way to go. In the end either way is gonna cost about the same. The radix system is probably the best option for streetability when you're talking about 400+ rwhp. The thing that I always think about though is how FI can become very picky/exspensive when you start messing with smaller pulleys and such.

Either way Scream I don't think you can go wrong.

John

 

Thanks for all of the info guys! I'm going to start looking for an LS1 (or, if I'm really lucky, and LS6) to start building this fall! Maybe by this time next year I'll have her done!

 

How much would a LS6 complete block run? Can a 5 or 6 speed manual tranny be installed?

I wonder if this would be a better alternative to a supercharger?