Shelby Aluminum FE rebuild for the watersnake

[snakehunter]

Hello all,
I'm working on CSX4158, which was in a flood. We're rebuilding the whole car.
CSX4158 For Sale, but Salvage due to Flood

The engine suffered only damage from excessive wear (possibly due to 'dirty' assembling/inexperienced builder) and the only real water damage inside was some light pitting on the cylinders. I'll post pics from the machinist as soon as I get them.

To correct this, we're going to be going .030 over to 4.280 which will make it a 473 incher if I'm correct. This will require new custom pistons from Arias.

Otherwise, the motor is the standard Shelby package -aluminum block, heads, dual plane intake, eagle rods, shelby rocker arms and shafts, etc.

CR will be 11:1. The car had a huge 312 duration/611 lift cam that I don't think was a good fit for the car. I'm considering going with something much more conservative like the Comp XE284H (284/296 degree/588 lift) or 292H (292/560"). I believe I'll get similar power but it will be much more streetable.

I'm not after huge power numbers, but don't want it to be a slouch either. Is 525hp reasonable with this package?

What do you guys think? Anything else I should change while I'm in there?

[CSX4815]

Did the heads come off with the engine in the car... with the studs in place?

Thanks!

[mickmate]

Give Shelby's engine shop manager Robert a call and run those cam numbers by him and see what he thinks. I think it will make about that for HP with your proposed cam.

[snakehunter]

Cool, thanks.
The heads did come off in the car, but it required the motor mounts to be undone and a gentle tilt of the block to each side. It clears the top of the footbox by about 1/2"!

[RodKnock]

Have you contemplated a roller cam and possibly a lower compression ratio?

That's fantastic that you're sharing the Shelby FE build.

[RICK LAKE]

Snakehunter Rebuilding the block is not a problem. Since you are going to bore the cylinders and have custom pistons done, Can the jugs go .015" to clean up? 4.265" is doable with cutting down the rings to fit. This will give you 3 more rebuilds on the block with a .030",.045".060". As far as size of motor, you will need something in a .575" lift to just cover the extra cubes of the motor. I run a crane small hydro roller camsaft in a 482 motor and think this would be also right up your ideas for a great motor. You have to realize that torque moves the car no HP. This cam in my motor is just under 600 ft of torque. It's over 400 from 2,000 to 5,200. HP is in the mid 540's at 5,800 rpms. Car has a little lope in the motor and will idle at 775 all day with out any issues. Blows the tires off in first 2 gears. What gearing and trans are you running?? I am only running 10.5 compression and premo gas at the pumps. 91 octane. The cam specs are .587-607" with 6 degrees retarded. I am going to advance it 2 degrees to kill some of the torque in the bottom end. Max rpm is 6,500. I run a chip of 6,200 in the MSD. Tranny gearing and rearend ratios are what will effect how the car runs. I have a 5 and 6 speed for the car with 3.31 gears. I may switch to a 3.07 ratio. Both tranny have 3.00 first gears and .86 over drive in the 6th speed one. This is for big tracks where she can stretch her legs. Limit is still 135-138 mph, but it's how you get there that's the fun.
Your motor looks most surface rust. boil clean it and see what the machinist says about it. Find a pro machinist that knows how to build aluminum motors.
1 side note. If the manifold has not be ported, send it to Joe craine for one of his great port jobs. He makes all the port flow within 5 cfm of high to low. The stock manifold can be as high as 30 cfm out. If you want some more info, send me a P-M. Rick L.

[snakehunter]

Rick,
That's great info, thanks. I'll pm you for more.

The block has been tanked and cleanup honed as of a few days ago, and I'm told it has a number of light pits. There's also some up and down lines on the thrust side from dirt (oddly, the bore is almost perfect dimensionally). Machinist is concerned it will use a little oil but says otherwise it would be fine without going overbore.

He's very good with HP motors but doesn't do a lot of 'high dollar' motors like these (no other way to say it). He also tends to be pretty conservative when it comes to making calls like this.

I think I'm going to have to go up this weekend and shoot pics in person to make a decision. Not trying to cheap out but if we don't need to toss out $1000 on pistons I can easily spend it elsewhere on the car.

.015 is worth trying, Arias said they can make anything I need. It just sucks it will take 4-5 weeks to get pistons. I was hoping to have this thing running and on the street by then!

[DAVID GAGNARD]

Snakehunter;

The block has been tanked and cleanup honed as of a few days ago, and I'm told it has a number of light pits. There's also some up and down lines on the thrust side from dirt (oddly, the bore is almost perfect dimensionally). Machinist is concerned it will use a little oil but says otherwise it would be fine without going overbore.

Talk it over with your machinest, a good hone on the cylinders may be o-k for what you plan to do with the car....
If your going to drive it a few thousand miles a year, I wouldn't worry about it and spend the money elsewhere on the car.....

I recently overhauled a 351-W for my neice's husband, it was going in an old hunting 4x4 and he didn't want to spend a lot on it......all cylinders had wear, some as much as .022 thousands........I told him so and he asked if I could just hone the block and put in new rings/bearing and how would it do. Told him it would do fine, probably burn some oil, but run fine, so that's what we did.......damn thing runs great, I guess cause it's a "little loose" it revs up real quick and runs great. Oil consumption is very minimal and you hardly see any blue smoke out of the exhaust, it's doing a lot better than I expected...........

David

[DavidNJ]

The key is dynamic compression ratio not the static one. Going to a more conservative cam that closes the intake earlier raises the dynamic compression. Numbers on LS1s used on the street are typically under 8.8:1. Even then, you are skirting the limits of pump gas. Using a racing gas avoids that issue.


http://www.kb-silvolite.com/calc.php?action=comp
http://www.wallaceracing.com/dynamic-cr.php