Blower engine questions?

Hi

I have an old, stock bore, 2 bolt SBC (3970010) with 3998920 smog heads (1.94/1.5 valves 76cc) that Im planning to rebuild and supercharge with a weiand 177.

Can I reuse the cast crank and rods and will the 2 bolt mains be a problem? A ARP main stud Kit would help, wouldnt it?

I will be using forged pistons.

Its only going to be a fun street machine not going over 6000 RPM with hopefully 450-475 HP on crank.

Any ideas and suggestions are welcome


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It will work fine. Spend the money from the main stud kit on a complete ARP engine bolt set. Have the 2 bolt main saddles checked and align honed if nessessary.
Use a -22cc forged or hypertech (large ring end gap) D dish piston. Fully home port you heads and drill and pin the rocker studs. consider larger 2.02x 1.60 valves. A Lunati street cam such as this one will make great power and rpm with the 177 and drive easy on the street.
Use Lunati 73943 or equal springs.
The stock GM rods are fine after a resize w/ARP bolts.

Thanks alot for your reply

I run a manual transmission (muncie), will that be driveable with that cam? (2400 RPM stall)

Yes its a very street friendly cam.

Nice, how about the heads?

I found an old thread where you recommends a set of WP 200cc Sportsman II 72cc heads instead the smog heads. Will my HP with those heads exceed the strength of my crank, rods & 2 bolt block?

http://www.hotrodders.com/forum/reb...ighlight=blower

You worry too much.

if you're looking for 475 hp and 6000 RPM max then you really don't need forged pistons, aome good quality cast ones would be fine, and in some ways even better in your application- not to mention cheaper. Just make sure your tuning is pretty close to optimal and your not running too much timing or too lean of a fuel mixture (nor overly rich).

well, actually I would like to have as much hp as my block and rotating assy can handle... I was just thinking 450-500 hp was about it?

I going to install a MSD-BTM, A/F meter and probably also a knock sensor to hopefully prevent me from blowing it up

That probably is a good ROT, especially with those heads. If you want to go over that then you'll need a very well prepped factory block, or an aftermarket one. pistons are not your limiting factor though and improving in that single area really won'd do much for you. cast pistons expand less and in a lot of cases weigh less- two big advantages. They are weaker than forged, but at your limited level not really necessary.

I have a similar (350 SB with a weiand 177) build in the works. .
It happens to be a 4 bolt block but....... stock cast crank, stock rebuilt rods.
I'll be using KB D dish low compression Hypers.
I have a set of 920's that are almost done porting. May use them or may get a entry level aftermarket head.
The Edelbrock E-Street and/or Brodix IK200 look like a good deal to me.
I'll cross that bridge when I get to it.
It'll be plenty strong.
As long as you avoid abnormal combustion and give it the fuel quality it deserves, supercharging is not that hard on a motor. Excessive rpm is much harder on the internals. Detonation and pre-ignition is very hard on the internals wether stock, aftermarket or what ever.
The KB forged pistons are very reasonable in price and reported to be very good. If one fits the required application specs and you can swing it, go for it.

Thanks for all the good advices. 94-95 octane are commonly available overhere so I just stick to that.