So, would you say it would be better to get a LS7 shortblock then a LS2 427? What are guesses as to how much they (LS7 shortblock) would cost compared to a C5R short block?

 

The C5R block offers zero in the HP department over any LSx block. I think the only advantage of the C5R block is that it can be resleeved if there's a problem. Maybe there's something else too. Oh yeah, its alot of money. Its just like the C5R intake costs around $11,000...this one does the same job and looks just as good for $3,000.

http://www.harrop.com.au/products/intake_systems.html

And like mentioned in this thread. Any LS1/2/6 based 427 engine built by a good sponsor will have MUCH more power and torque, and a 2yr/24,000 mile full warranty. You buy a LS7 crate or short block especially and you have no warranty at all.

 

We resleeve blocks. Katech isn't going anywhere, trust me.

 

LS2 427 case with Katech mains/ARP main studs/line honed $4200
C5R case from Scoggin ~$6400
LS7 case $TBD

 

Am I right about the only advantage of using a C5R block is the re-sleeving capability? Or is the other advantages?

 

We were scrapping 30% of LS1 cases that we were resleeving becuse they didn't meet our quality standards. The LS2 cases are much better for resleeving so that is all we are doing now. Customers have never had any problems with our LS1 resleeved cases.

 

There are slight advantages in casting differences and the type of aluminum used, but for a street engine its not absolutely necessary. Sleeved LS2 cases are just fine.

 

I presume there's some power level at which the C5R block becomes the prudent choice? I know the various Bow Tie iron blocks have HP ratings from ~450 to 850...

 

I was told that the C5R block offers zero in power output advantages. IIRC, the C5R was designed for about 650 RWHP, no more than that N/A. The same as any other LSx block.

 

They run such a small piston to wall clearance (0.001 or something stupid tight) that the piston slap isn't a problem, but long term durability could be effected

Ryan

 

Even though you get a warr. from the sponsors. What happens if the sponsor is in cali and I am in new york or better yet the sponsor goes out of business? Atleast, with the LS7, you can just go to your local dealer for the warr work. Well, unless GM ends up sh****ing the bed ...

 

There are certain shops that won't be going out of business any time soon. My builder was 2,000 miles away, $500 to ship it both ways when it got rebuilt from intake to oil pan for FREE. It was not their fault it had a problem either, but they rebuilt it anyway.

Also, no matter what engine you have, if it blows under any warranty period the engine has to be R&R'ed to repair it, that has to be paid for by us. Only the engines are warranteed, not labor. No way is a dealership going to pay for that with a crate engine retrofit project.

And...there is no way on gods green earth that if someone brings there retrofitted F-Body/car into a dealership and says, "hi guys, I bought a Corvette LS7 crate engine and installed it myself, it blew up but it's still within the 12mon/12,000mile warranty the place I got it from said I had, I want a new one installed pronto, take care of it and I'll pick it up in a week, thanks".

You'll come back 1 week later and the service writer will just be getting up off the ground from laughing his *** off.

It will not be covered in any way, shape or form. It clearly says in the LS7 warranty (not quoted exactly): that they will void it if any non-approved parts are used in conjunction with the LS7 engine. That means ANYTHING will void it because these are all retrofits going into Monte Carlo's, RX7's and F-Body's. Not to mention, GM has no control over how people tune these things. They can blow up on the dyno or right after they get on the road. Which includes tranny's, radiators, rear-ends, exhaust systems, induction systems, etc. I'm sure they can just say if you don't use 100% Corvette parts, your warranty is void, which is the proper thing to do. They'd be shipping new engines for free every day otherwise.

People who tune their BONE STOCK LS1/2/6 for that little extra are VOIDED, if the dealership finds out.

People will have a rude awakening when they try to get a brand new LS7 engine sent to them when one explodes.

 

Hasn't ARE gone out of business a few times already? It was ARE, then some different form of the name, and now Autoworx or something? Both have gone bankrupt and ripped a bunch of people off for a lot of money so either you are a very special person or a very lucky person. I know which one I would bet on.

 

Probably a little of both

ARE was the best/fastest engine builder for alot of years, and the people who built the engines are still some of the best on the planet, thats why I went with them. Why they went out of business I don't know. But, I collected on my warranty 1 1/2 years after purchase, LS7 crate engine owners will never collect, and GM isn't going anywhere as a business, GM just isn't going to hand out free motors when DIY'ers blow them up.

 

You guys are making me feel a little better. I'm building a motor that'll handle at least 1800 hp without any problems (billet rods, or custom CP pistons will be the weak link), and will actually make up to 1600 with the turbo setup I'm using. The whole setup is going to cost me right at $15k, and I thought I was out of my mind for doing it. Thanks for making me feel better,

Chris

 

Only $15k for a motor good to 1800 hp seems to good to be true. Unless it's a used piece that just got freshened up or something...1800 hp is some SERIOUS STEAM.

w2w said they made around that hp with 'casper' and the shortblock alone in that car was right around $15 grand they said if it was to be duplicated.

 

Well, I don't know what Casper is, but the only used peice in my shortblock will be the Sonny Bryant Billet crank that will be closely inspected before installation. Everything else is brand new, but I am saving about a grand on the rods by getting them from a guy that can't use them. Paying $600 instead of the $1800 the manufacturer charges.

The internals look something like this:
Dart Iron Eagle 302-based SBF with 8.200" deck
Sonny Bryant crank
Oliver 5.4" billet I-beam rods with upgraded rod-bolts
Custom CP pistons

The AFR 205 heads are used, but have only had a few passes on them and are in perfect shape. Saved around $700 on them. If I built the entire motor from oil-pan to intake and TB with brand new parts, it'd probably cost a total of 18k (another 2000 for the crank and another 1k for the new rods and heads). And, that includes labor.