pistons... 355

chevyman92

Member
Joined
Feb 11, 2010
Location
Mills River (outside asheville)
which style pistons are the best for a mild build for a 355? flat top, dish, dome, etc. i used flat top on the last build for just a stock engine. but i want performance out of this one. and was hoping someone could give me the insight.
 
On my 355 build, I'm using falt top 4 valve Silvolite pistons, stock deck height, Vortec cast iron heads (not milled). I think I'll be around 10:3 compression when I'm done but not sure. I really need to cc the heads and do more measuring.

If I was doing it over for performance, I would do dish forged pistons, deck the block some, mill the heads and throw some go go juice to it.

Look around on the web for formula calculators and run different numbers to figure out the compression that you want. If you want pump gas or if you want to run high premium race fuel. Or some where in between. Remember the quench area makes a big difference and dish or dome will affect that greatly.

BUT I'm not an engine builder. I just read a lot. :)
 
chevyman92 said:
which style pistons are the best for a mild build for a 355? flat top, dish, dome, etc. i used flat top on the last build for just a stock engine. but i want performance out of this one. and was hoping someone could give me the insight.
Click to expand...
It all depends on what you want to do with it. What fuel do you plan on burning. What CC combustion chamber heads are you running? Its proven flat top pistons are more efficiant than domes. Not just telling you that, do some research on it.
 
There isn't a "best" piston to use. You need to choose your piston type based on your specific build. What heads are you running, how high of a compression ratio do you want, are you planning on running pump gas, etc need to be taken into consideration
 
In my Yj I got JE 9.71 .30 and with double hump head with some work I ended up around 10.15:1. If done over I would use vortex heads but I didn't have a intake for them. Loves 93 gas and got great power for a Yj on 37s
 
i'm not looking for ridiculously high compression. its goin into my 95 chevy which i plan on using for just 4 wheelin. i wanna run pump gas for sure, and the go go juice i've considered as well. for heads i'm either looking at vortec 305 heads, as i've heard they are relatively cheap and easier to come by than 2.02 heads. and they will get the job done. but its between vortec, or 2.02 heads. either way i think they are 64cc. i was hoping i could get it done without decking any of that. i'm wanting somewhere from 400 to 450 to maybe even 500hp at the most.
 
if you're building a 350 based motor, stay away from the 305 vortec heads, you want the 350 vortecs, the flow numbers are way better and the combustion chamber shape is better as well.
if you're using a 64cc head, a flat top with valve reliefs should put you really close to 10:1.
for vortec style heads, you need a tall-port style intake to match them. the exhaust manifold is a bolt up with no changes.
what type of fuel system are you going with? if you're using tbi, then you would need either an adapter plate to use with a carb intake or a tbi-to-vortec head type intake.
also to consider, what is your cam profile?
 
comp cams xtreme energy summit racing cca 07-501-8 was the cam i was thinking of. 264/269 .488/.495
i haven't looked at intakes too much, but i have looked at the edelbrock performer tbi intake. i have a lot of research that still needs to be done
 
for factory style L31 vortec heads, .480 lift is the max, when you go higher, the valve guides will need machining for clearance or the valvespring keepers will need to be changed. I'm going to assume this is for the 95 in your signature-what gears are you running? automatic or manual?? if automatic, what stall is your converter? also what is your intended use of the truck? a lot of times, people put in big hot-rod cams that sound cool, but fall on their face and finally get off their a$$ about 3000 rpms-not cool for a 4wd, look into a little more conservative cam with low & mid-range torque and it will have more usable power. this is especially true running a TBI setup, they're awesome for bottom end and mid range power(and easy to work on!) but for power much past 4000 rpms, they just run out of flow. with the TBI setup, plan on a custom chip if you go much past stock, the lopey cam profiles confuse the computer to no end.
 
Back
Top