355 top end questons.

[langdonracing48]

Hi Everyone. i just built a little 355 back up engine. my lower end consist of a scat 9000 lightweight crank(46lbs), scat h-beam 6" rods on wiseco 12.5:1 forged pistons. im racing on a 3/8ths mile, medium banked paper clip shaped dirt track. i don't want to turn this motor over 7200 rpms. i have a choice of 2 top ends. the first, is pro topline steel heads, 220 intake runners, 64cc combustion chambers, 2.08/1.60 valves with a Doug Herbert P/N C6F (SM) Roller Cam, .625 lift, advertised duration is 299/308, and duration @.050 is 261/270. i like the heads, but i think the cam is gonna absolutely kill me on restarts and coming off the corner. my other choice would be a set of world sportsman II 200cc intake runner, 64cc chamber heads with 2.02/1.60's in them, set up for solid flat tappet. i dont have a cam for these heads, so i can buy whatever i need to for this. if i had money for a different roller cam theres no doubt i'd use the toplines, but being on a budget i think im gonna be a lot better off just sticking with the sportsman II's with a solid f/t cam and save the other top end for a 377 or something down the road. i was wondering what the experts on here think? am i correct in assuming the roller cam is far too big for a 12.5:1 355? thanks for any suggestions!

[langdonracing48]

was thinking about possibly using a comp 12-688-4794, or 12-689-47 cam if i run the sportsman II's, but im very open to suggestions. a lot of people i know seem to like the elgin 1090p cam, but im not sure what size motor their running either.

[dereksehi]

You are right in my opinion if you are only gunna run under 7200 that camshaft is too big and will be dead on restarts also 220cc heads are also too big in my opinion for a 355 in that rpm range if those two were combined the engine would struggle on bottom end power.

[jsf74]

For a budget ft cam a elgin1090 is hard to beat for the price. thats what I would use. Im not a expert though.

[50j]

I think that the smaller heads would be better on a 355. Pro Topline heads are good, but a 220 would be a little bit big IMO.

[let-r-eat]

WP heads and crower 00306 cam.