Quote:
Originally Posted by buddiiee
Hello guys. Im here again for my buddy. (his computer isnt working right now)
He has a 70 cutlass, with a '72 455 olds in it. He just knocked a rod thru his oil pan, and is going to rebuild it. I told him, to stick to as close as factory as you can. they're a proven design that works, and that, when not too wildly modified, are easy to get support from, from boards like these.
My question is, where can I find a site, or book, that shows every part number for the 455 that was in the 70 442. I'm trying to recreate the engine that had '365 bhp @ 5000 rpm, 500 lb-ft @ 3200 rpm'. Well, that's my goal anyway. Can these parts be had anymore? If not, does anyone reproduce these parts? I'm lookin for the heads, cam, crank, and intake. Also, what was the factory cfm on the carb. On those rare heads you guys have, the hi flow versions. are they soo desireable, because theyre stock? im guessing theyre going to cost a pretty penny. are there any aftermarket heads that flow just as nice, but cheaper, because theyre production?
My other question is, where there any physical differences in blocks, between the 70 and the say, 72 for example? (besides nickel content)
And what about main caps. Is there any billet steel mains available for these engines? Thanks for any help guys.
|
First, the nickel content thing is an unproven urban myth. Don't worry about it. Second, the fundamental differences between the 70 and 72 455s are the pistons (higher compression for 70) and the cam profile. The 72 should have come with Ga heads. These have factory induction hardened valve seats but will have small 2.000" intakes unless the engine came from a W-30 or manual trans 442. You can have the heads cut for the 2.070" intakes, but you'll remove the hardened seats in the process. Aftermarket press-in seats will be required.
I'd recommend aftermarket forged pistons. Note that the advertised compression ratio of aftermarket pistons assumes the stock steel shim head gasket. The FelPro blue intakes have a thicker 0.040" compressed height and will lower CR about a quarter point. Similarly, the advertised CR assumes the blueprinted 80 cc chambers but big block heads run 83-84 cc as-cast. Taken together, these factors will reduce an advertised 10:1 forged piston to a more streetable 9.25 or so.
I'd also recommend an aftermarket dual pattern cam instead of the symmetric 70 cam.