LS7 build?

[MatNova]

I've been trying to learn about these LS1 engines for the last couple of weeks (thinking about throwing one in my Chevy II), but there are so many differences, my head is spinning. If you guys could set me straight, I'd appreciate it. I'll let you know what I need to get at the flywheel, then you can help with the rest.

This motor is going in a 3000 pound 62 Chevy II post car.I'd like to have at least 500-600 hp at the flywheel without any turbos or roots supercharger.

I love reading Hot Rod, but they never tell you what stuff costs, so I'm thinking an LSX block with LS7 heads, and a hot cam are what I need, or do I? Can I get away with a truck block and LS7 heads, are they compatable? Sh$t, I don't really have a clue, let's be completely honest about this before we get too far.

I'd like to spend $5K on the motor, and $2K on a tranny, but cheaper is always better. (a combo maybe?) Someone said I don't want to fool around with an aluminum block, especially if I decide to put nitrous on it. Thanks in advance fellas.

I'd just like to start the suggestions going, prices would help me a ton. Matt

[Mr. Luos]

With that LSx block and heads...you will have NO PROBLEM making that power.


Personally, save the $$ and go with a 402/408.
Maybe LS2 stroked to 402.
My 402 makes 635-640 at the fly.

[Hi-Po]

LSX block Retails for 2 grand. So now you have 3 grand left to spend on your engine.

LS7 heads I think can go for 400 each. Thats 800 . Your up to 2800. You will now need some nice forged internals, crank, rods, pistons, .... the little shit... rings, rod bolts, .... basically you will be over your 5000 budget.

If I were you I would buy thishttp://www.texas-speed.com/shop/item.asp?itemid=46&catid=28

Its going to be really hard to piece together a long block for 5000 even. In my eyes at least. You would also need the ECM and harness for these engines since you dont already have a LS1 car. You could go carbed and probably save alot of mulah.

Lots of guys around here are running the LQ9/4 truck block (iron" and making the power you want/need. I would start searching the web for that.

402 or 408 will be a absolute torque monster. Hope all my info was right, and it helped alittle.

[Hi-Po]

damnit, you beat me to it.

[UTVols98]

Go with the 408 motor from Texas Speed. For 3600 with internals, and 1600 left for heads and intake. You'll definitely go over budget with everything you need, but will have a power monster. Prob best bang for the buck on the market.

[MatNova]

Thanks fellas. Will the LS7 heads work on that short block? Or are the L92 heads similar quality? Why not more cubic inches? Cost?

Most likely going to run a carbed set up: GM or Edelbrock intake...others? What other electrical would I need?

Also, is there a way to mount the coil packs in a "hidden" location for an older application. Once again, thanks, pictures in the next few months. Matt

P.S. Is there a book I can get that has some answers for me?

[Mr. Luos]

When it comes to cost...that is why you don't see as many LSX blocks out there yet. Pricey.

With the space you will have under the hood with an LSx small block, I am sure finding a different coil location would be pretty easy. But, I like keeping them where they are. Shorter distance for the spark to travel.

The L92 heads will fit on the LS2/LQ9 blocks. I assume the LS7 heads would as well.

No idea if there are carb manifolds for those heads yet.

[rapter34]

not to metion aren't the LSX blocks back ordered somthing firce.

[MatNova]

What type of electronics would I need if I utilized a carb set up? Is there an aftermarket wiring harness, sensors, etc? I read that an MSD box to manage timing curves is a must.

Right now, I'm using a timing light on a 1949 Ford Flathead, so my level of sophistication is loooooow.