I have a comp cam 275deh cam in my 355 or 360 or something or other. Its a 60 over 350. Anyway the cam is made to rev to 6 grand but i dont think the heads will support that powerband?

The runners are ported and polished and it has a little bowl work. The exhaust runners were cleaned out but arent polished. They have a 76cc combustion chamber... i think. 8.5:1 cr.

Do you think 882 heads will support a 6,000 rpm powerband? The motor will be pretty useless with 4500 rpm heads and a 6000 rpm cam.

If these heads wont cut it then what are a stock cheap head that will.

yes its a 4 bolt block.

 

882's have a 170 cc intake runner. They will flow great numbers for production heads but most people shy away from the because of them being a 76cc smog head. They will rev to 6000 as long as you have the right valve springs.

 

Intake runners should not be polished...They need a slightly rough surface to keep the fuel atomized... Slightly ported...got to wonder what that means... Was this done by a cylinder head shop or just somebody in the garage??? For many years I've been extremely suspicious of heads that are ported without the results being verified and the flow equalized on a flow bench... I did cylinder head work for a number of years, and many of the "ported" heads that came into the shop when checked on the flow bench were junk!!!

The exhaust side runners should be smooth as possible, they only thing they have to do is get the exhaust out of the chamber as quickly and efficiently as possible!!!!

8.5:1 compression is bordering on anemic... the easiest horsepower you could get is turn them old smogger heads into boat anchors and put on a good set of heads that have runners flowing in the 170 to 180 range.... There is so much horsepower to be had with the proper heads done up correctly, an easy 50 to 70 horsepower when the heads are selected to compliment the rest of your components, and not merely bought on a whim cuz somebody said they worked on his car!!!! A well balanced and well thought out engine build does not have to cost a fortune, but your engine will run like it did!!!!!!!!!!!!

 

slightly ported means i took a dremel and smoothed all the shitty bumps and port matched the headers and heads. I did the same for the intake manifold. But the intake runners were smoothed out when i got them with the motor. The springs compliment the cam and lift. Its got stock ratio roller rockers on it too so it should be ok. I wish there were an easy way to up the cr. The motors got flat tops.

I honestly can't afford heads right now. Nor would i buy aluminum heads on a motor that could throw a rod and bend them to sh*t. I was considering vortec heads but i dont even know where to try and get a pair for cheap.

I figure if the cam is made for 6000 rpm then i should have heads to compliment it. Im not sure what runner length is good for this? I guess 170 to 180 since you mentioned that. I know the shorter the runner the higher rpm it usually is designed for. Not sure whats a good length when it comes to choosing heads for motors that dont usually see over 7000, i didnt think they designed many heads to produce power over that.
average runner lengths are 165cc, 170cc, 175cc, 180cc, 185 up to like 210 cc. I really wasnt sure which runner length was good for what rpm ranges i cant really find a site that specifies powerbands. WAIT??? Does the "cc" of the runner mean anything about the length???

Please help me out THANKS.

 

no, it has nothing to do with runner length, only the volume of air it is designed to flow expressed in cc's... Length is dictated by the engine angles and intake placement....

I've seen some interesting results with the Vortec heads... Decent power at minimal cost!!!!! I just hate to see you waste anymore time and effort on a pair of large chamber smogger heads.... A set of small chamber Vortec's with just a touch up on the valves will do much better....

RPM is relative to what the cam, heads, and exhaust are designed to work at... I've had a number of different breeds small blocks that have all the power in by 5500 rpm, no reason to rev beyond where your power band is, especially on an old engine that you are unsure of.... For street use, I'll take low rpm torque over high rpm horsepower any day!!!! Just changing your heads out to a small chamber factory head will help your horsepower and torque situation a bunch!!! Compression is horsepower!!!! The higher you can get the CR and keep it from detonating on the fuel you use, the better power you have.... I run all my street performance stuff on E-85 and bump the compression to the high 11, low 12:1 range. Drag racing, we use E-90, and run the compression at 13.5:1..... Increasing the compression by a simple head swap is cheap power!!!!!

 

i would love to be around 10:1. I wont rev the motor out to 6 all the time but if it can then why not : )

i dont want to havta go threw the work of making the vortec heads fit bigger valve springs and valves.

Im gonna look for someone selling already beefed up vortec heads.

 

Sounds like a good plan!!!! With a bit of searching and some patience, I'd bet you can come up with a low mileage already done set of Vortec's that somebody ran on their car and decided to upgrade to aluminum heads or something!!!!! Probably save you a bunch of bux!!!!!

 

WE CAN ONLY HOPE : )

 

Not that I need SBC parts but I wouldn't take 882 heads if they were given to me. They're boat anchors. There are much better castings to pick from, even from other smog head castings.

 

882s are no worse than 993s or 487s, and they're way preferable over 624s. The 882s are starting to become scarce, because they almost never crack, even with big valves and porting. These heads don't really respond to 2.02" intake valves, however. Even with expert porting.
For the OP I'd suggest the ubiquitous Vortec heads, but virgin 882s do have a place in this world, and it isn't at the bottom of a lake.

 

Well ill try and sell the ported 882s and buy either a set of:

RHS Protorker Vortecs
http://www.summitracing.com/parts/CC...7/?image=large

or

RHS Pro Action Head
http://www.summitracing.com/parts/CCA-12317/

Im going to do more research and if they flow about the same then ill get the Pro Action because then i do not need new valve covers and intake manifold and such.

 

I also remebered i have my 305 heads. they are 1986 416 heads. Completely stock. So they would need work.

BUT! i also found a cheap set of new rebuilt chevy 416 heads with 2.02 and 1.60 valves. Im not sure if they are ported at all yet.

What are the runner CC on 416s? How much can they be made out to? Would 416s with big valves be better on a 350 because of the compression??? alot of people say yes and alot say no.

Would 416s flow to 6 grand? Supposedly they are the best 305 heads made and with big valves they must be sorta good???

Let me know what you think.

 

No amount of porting on the 416s will get them anywhere near the RHS heads, and it's all in the short turn of the intake port. That's exactly why the '96 Vortec 350 heads outflowed any other 23-degree SBC head that ever came from GM before. Another thought is the combustion chambers: the 416s have the old bathtub design, which doesn't make as good of use of the charge at the more modern chamber designs. Sell what you have, get either of the RHS heads, and have no regrets.

 

I'll take them 416's off your hands :O

 

ok : ) sending pm.

Which RHS head would be better? The vortec style or the pro action?