I am looking for some suggestions on cam and pistons for my 70 455 build, stock 3.42 posi, 400 turbo & power brakes. I want a healthy street car that will run on pump gas. Deck height 10.542 looks like about .028 cut. Need to go .030-.040 over bore. I do not want to cut the deck any more than has been. I know things have changed just lately for 455 pistons Stage 1 high flow severe duty valves and PAC springs. Massage (port match) the heads and had them cut for the springs & PC seals. (Thank you Gary for the info.) Plugging the heat cross over. Stock intake with some modifications (Thanks Rob for the info). Exhaust manifolds opened up. But I do have a set of the MT headers. Just not sure which I am going to use. Stock rods matched smoothed, polished and ARP bolts Std crank polished Everything will be balanced All the above items are finished Things to do yet plus some not listed. Going to update the front and rear seal. Modifications to oil, block, pan, tube & cover I will use a small Hughes converter 2500. T/A dual groove cam bearings. Custom fit pushrods Roll master timing setup I used a Scott Brown cam 226/240—112 /498-481 in my 72 but I am thinking I might need something a little bigger. Thank you for any help Nelson
If your not going to spend a good amount of time at the drag strip , or run those headers then I do not see much of a need for anything more then the Cam you posted about , or maybe do a Hydro roller Cam with specs close to that! Those heads peak in flow with some 215 cfm@.550" so Cam wise I can see going up to around .525" lift, but the Exh side needs help as the average Exh to Intake ratio is 68 to 71% depending on the lift you test it at, so a duel pattern Cam like you ran is what's needed, and as for my 2 cents worth I think you need to run the headers if your looking for the most out of your combo! You likely will need a dished piston with those 1970 heads.
Get the DCR calculator and figure out what your DCR is with that cam and different static compression ratios. With iron heads, aim for a DCR around 7.5-7.8 to run on pump gas. Once you know what your static compression needs to be, get a custom piston that will get you there with zero deck. The Autotec pistons look like a great deal.
My 455 block is decked to -.006 with a Felpro blue gasket .045 thick, I installed TRW 10.25:1 forged pistons and ran 93 octane gas with no problems 15 years. I set timing @ 30 degree total with no vacuum dash pot . The 113 camshaft should give you enough vacuum to run power brakes and send you tp the tire store for rears fairly frequently.
