Some here may remember that I lost a piston in my ProCharged C6 several weeks back. All my parts finally arrived, and during the honing process of the block (LS2) it was discovered that #7 cylinder wall was cracked. I will have to replace the block.

My question is, should I go back aluminum, or change to an iron block.

I have one knowledge source telling be to stay with aluminum, as the iron block is 65 # heavier. Another source says swap to iron for the increased strength.

I will be running a D1 ProCharger with 12 # of boost.

The aluminum camp says that there are aluminum blocks making 1200+ hp with no issues, but, my original block failed running only 6#.
Will an additional 65# of weight on the front of the car affect handling that much, and. Would the additional insurance of an iron block be worth it?

Thanks for your comments.

 

Your original block likely failed because of the piston failing, NOT because of the increased cylinder pressures in and of themselves

I would stay with an aluminum block personally. Less weight and they seem to run cooler. That is, unless you're going for something just crazy.. 1200+RWHP

 

I had this same issue and went iron block, but I also want to make big hp later down the road. the 65lbs is not a big deal and some after market seats can easily drop that much. the iron blocks are wayyyy stronger and I'll pay 65lbs to have peace of mind that 1,200whp is possible and anything less should be easy. If you talk to engine builders also, like MTI, they say the sleeves of the aluminum blocks are on the edge at >800whp and some guys do it but other guys blow up. Or talk to LME, HKE, etc and none of them will recommend the alumn block at 800+ whp. I konw that's like asking a barber if you need a haircut but for what it's worth.

i got a crazy deal on LSX block 427 but otherwise my planned setup was stock stroke iron block setup with basic callies forged internals, etc and 1/2 head studs.

 

Thanks guys.

I sprung for the aluminum block. I hope to make a 700 hp with a (very) conservative tune.

408 cid
Lunati stroker forged crank.
Comp H-beam steel rods.
Wiseco 9.5 cr forged pistons.
Bullet blower cam
Lunati link-bar roller lifters
Lunati bee hive springs
Comp Ultra Gold rockers
Comp 3/8 moly pushrods
Meziere electric water pump
Melling HP oil pump
DeWitt shorty radiator w/eoc
D1 ProCharger w/ Flip Drive
Marren 80# injectors
Peformance Products 'Typhoon' aluminum Intake manifold
Kooks 1 7/8: hedders
Corsta Sport dual tips

Now all I need is a Z06 differential to go with the Z06 tranny sitting in the garage. Maybe next month?

The car made 550hp with a PS1 and stock engine and hedders. Honestly, that was about the 305 Invo's could handle.

 

700whp should be cake and that thing will be a torque monster. few suggestions:

1. I'd skip that intake and use the stock intake manfold. Sinister, arun and countless others have made 1,200whp+ on stock ls6/3/7 intake manifolds.

2. strongly suggest go with dallas big mouth or some other 4" intake on the D1SC as the stock dongle plastic thing sucks bad and robs you of about 35whp

3. flip drive is way overkill on that. I made 760/700 on a D1SC with 8" crank and 3.9" blower on normal 8 rib with 12psi. car made ~700whp with I think 4.2" blower pulley also

4. not sure what heads you ended up with, the 760/700 I made was with mti cnc ported 243 heads and at 700whp I'd suggest going with something with thicker deck heads although lot of guys don't.

5. arp head studs of course.

6. stock rocker with trunion will work fine and much cheaper and proven.

7. been reading enough about the flip drive setups causing belt slip on the alternators and causing issues with fuel systems enough that if it was me i'd get billetech alterantor or something if i had flip drive, although I doubt you'll need it

8. I'd imagine drag radials are at least r888 would be required at that power level or it gets genuinely dangerous imo

9. not sure what your fuel pump setup is like but I was running the ECS stage 2 with the external A1000 and it's great.

700whp should be easy and reliable with that setup though assuming your tuner is good. I'm a huge fan of methanol setups too.

that should be a beast setup!

 

All the above parts have already been purchased or were alredy in the motor, ie, Typhoon, Meziere, Flip Drive, headers. Using ARP head, mains and rod fasteners. Planning on designing my own " big mouth" and engineering a cold air pickup further away from the radiator heat if I can. Fuel delivery is a concern and something I will probably have to address. A meth kit is also in my future.

It's a work in progress and I hope to have the car tuned and back on the road in 30 days.

Thanks.