355 sbc build
 

im putting together a 355sbc w/13.5CR,220cc heads,270@50/700 lift roller and tunnel ram.how much h.p. you think this combo will make?its going in my 70 chevelle w/ a 4-speed and 4:56 gear w/a 29.5 tall tire.car weighs 3500lbs.any suggestions are welcome on engine combo.[/b]

Re: 355 sbc build
 

:D Need a little more info here....what manufacturer on the heads, the cam lift and duration...you are running a tunnel ram need to know what you are planning to use for induction like carbs, their size, or if you are using fuel injection is it gas or alcohol...then maybe we can help

355
 

comp cam roller w/274@50 dur. and 700 lift.750's carbs and e85 fuel if i can run that kind of compression on it if not race gas.brodix heads

Here's my take: 355cid, fairly big heads, long duration cam, tunnel ram, 4-speed, heavy car = a real pig out of the hole. Your gonna need a LOT more gear to get it moving and keep in an rpm range where it's happy. 7500rpm plus would be my guess. Personally I'd ditch the tunnel ram and go with a good single carb race manifold, one 750 or 800 cfm should be plenty, race gas, 5.13 or more gear. I'll bet you could run e85, but getting it right will be a pain, especially with 2 carbs......jmo
Johnny

355
 

well i've got a holley strip dominator i can put on it.i can do a 5.13 gear also.i thought a 4.56 would put me through the back door at 7200 and now that i think about it that aint near enough.wanted to run e85 because i live in houston,tx. and its hot down here and its gonna see some street time.

cam
 

how big a cam can i get in a factory block?

You can put well over .700 lift in a stock blk. useing 1.6 rockers, but you are going in the wrong direction. A car that heavy and with a 355" engine will not perform in the qtr. or on the street. Anything bigger than .630 lift and 106 lobe ctrs. will only slow the car down unless you can keep it in the 4000 rpm plus range. Case in point my Malibu@3200lbs. 377" with a .668 lift is dead, just not enough torque. Engine performed very well in a dragster, but i would be better off with my .625 lift cam or even the original .597 flat tappet that i used to run. The only reason i haven't changed the cam is that i'm putting in a 434" motor. The car does run 6.50's and 10.59@125 with the 377 but it ran 6.45 with the flat tappet cam all on alcohol.

JMO

Zip.

Very good advice....I agree top to bottom.

355
 

so if i run a solid cam around 600 lift I'll be better off?What about the duration,was I even close at 270@50?What should the car run with that set up?I almost forgot,i guess 106-110LCA?

sbc vs bbc
 

maybe i should just put a bbc in it and go fast.whats your thoughts on that?think i can build one for same money sorta???????????