Super Charged 200

Hi all, after much deliberation on what and how to build my new engine i have decided to go with Weiand Supercharger, it will be the 142. I have purchased the first AussieSpeed 2V Blower manifold which is designed for this blower or a eaton m series. At this stage i am using my 68 200 engine and a 2V 250 head, the head won’t be decked and with a thick head gasket compression ratio will be under 9. The bottom end will consist of carefull prep and machining, will be fully balanced, ARP studded and bolted, pistons i haven’t decided so may use 2.3 Forged if the comp works out, the cam will be a solid cam designed for blower so not a lot of duration, head will be ported, bigger valves, stock height and will run Yella Terra roller’s, i will be using a set of 1 5/8ths pipes, into a single 3” collector and a spiral muffler 3” exhaust. Dissy will either have to be locked or a crank trigger coil pack system will be used. I will be running a V8 C4 auto, custom converter. Carby wise it will run a Holley blower carb, not sure of size yet. I have contacts in Australia for pretty much the whole shooting match. a friend does the ignition systems for the sixes. Or i am open to modifying the DUI i have now if that can be done. Fuel for this motor could be e85, we have service stations with e85, from experience this makes the blower cool to touch, protects against detonation and more power in boosted applications. Boost won’t exceed 10 pounds, i won’t be boost hungry as head gaskets are the weak link. I am hoping for well over 200 @ the wheels, with boost, blower and engine constraints i don’t see anything over 300. A similar Holden six that was running recently with a 4/71, 2 port Hilborn on meth was 380@ the wheels and ran 7.70’s over the 1/8th mile first time out.

You know you will have better detonation resistance if you set the quench height than if you go with a thick head gasket... Even with a slightly higher compression. 9:1 with e85 and a supercharger is kind of leaving a lot on the table. You can easily go 11:1 or higher with the E85 and a blower. Some things I have read suggest that even 11:1 is too low. Will kill your efficiency to go low compression and alki.

I know anything under 8 won’t be a good idea, not sure about that much higher as you suggest, depends on how fast the thing will spin, the 142 is designed for stock to mild 350 chevies, i may have to go higher in comp, but remember static compression and boost decide’s the effective compression, 9.0.1 with 6 pounds pushes effective over to 12.7.1 and that is detonation territory without some form of retarding it.

Yes, but E85 doesn't work the same way as gasonline. You can crank the boost and compression waaayyyy higher without detonation worries. Now that's all out the window if you think there may be times you run gasoline.

thanks Gary, it’s a bit to work out, i’ll have the manifold not week or week after. E85 where i live is available, so is 100 Octane from the pump. My concern is head gasket, i know Mike has a page on MLS gaskets, but nothing seems to have come of it, a local place does MLS custom head gaskets, a one off is 500-600 dollars.

Anyone have ideas on a decent harmonic balancer, i can get a chemically bonded one done, doesn’t seem to be much aftermarket performance type balancers available