Okay. i know roughly but im not 100% sure. Whats Chamber volume? like i have 76 cc chamber volume. and im going to a 64cc. and i know it will raise my compression. but what exactly is it?

And also whats Intake Port Volume?
the heads i want are 200 cc. intake port volume. but another set are 170 cc. but they both are 64 cc chamber volume, and 2.02 \ 1.60 valves.

whats the better head?
sorry if these questions are dumb, im only 17 and i dont know a lot of the detailed stuff.

 

Chamber volume is the volume of the combustion chamber in the head. This is mesasured in cc's normally, and yes changing form a 76 to a 64 cc will raise your compression ratio.

Intake port volume is the volume of the intake port in the head. This is also normally measured in cc's. The smaller the intake port is, the less air will get to the engine, but the velocity of the air will be higher since the port is smaller.

Looking at your sig, you have a mild 355, I think the 170 cc head will be a good head with enough flow and enough velocity to keep it responsive. You could do the 200cc head, but you would probably want to swap cams and see how that works. It really depends on what you want from your engine, but the 170cc heads should be good, I would stick wiht those, as I know bieng young, money is scarce.

Hunter

 

i am putting in a new lumpy cam. maybe like .224-.232 duration. and .480 lift. so should i still do the 170 cc. or go with the 200?

 

What is you new compression ratio gonna be? What carb do you have also?

Hunter

 

it will be 10:1 and i have a holley 600. but i just rebuilt it and thrw in some #70 jets, i might have to put on a 670 or something tho. im still a bit lean.

 

If you gimme your cam specs, head specs (who makes them, I can find flow numbers), and your intake, I will run both port sizes on engine analyzer and report back.

Hunter

 

alright, im bored out already. .030 over so take that into account.

Cam : Duration : In- 234° \ ex. 244°
lift, in- .488 \ ex .51

Heads: edelbrock 2.02 \ 1.60. 170cc. intake port vol. 64cc. chamber volume. 9\16 deck height. max valve lift. .575

Intake : Edelbrock Performer RPM Airgap Intake manifold.

and either sticking with my holley 600 cfm carb, or going with a edelbrock 750 cfm carb. which would make mroe power?

please give me some numbers from this. im runnin 8.85:1 compression ratio currently.

 

Alright so here we are:

With the 170cc Edelbrock Performer RPM heads and 10:1 compression ratio, the 600 cfm carb and 1.75" headers with 25 inch long primaries I got this

RPM HP TQ
2500 107 224
3000 158 276
3500 218 327
4000 247 324
4500 272 317
5000 298 313
5500 318 304
6000 324 283

That same combo with the 750 carb made about 6 more hp at 5500-6000 rpm.

For the 200cc heads I used the Edelbrock E-Tec heads. With these heads and the 750 cfm carb I got these numbers.

RPM HP TQ
2500 97 204
3000 143 250
3500 213 320
4000 242 318
4500 271 316
5000 304 320
5500 328 313
6000 340 298

So you can see the 200cc heads wiht 750 carb is what ya want I think, makes more peak hp and has a better torque curve. With some carb and ignition tuning you will be doing just fine.

Hope this helps

Hunter

 

I did the same chamber volume change on mine. It will raise it approx 1 point of compression.

The 170 vs 200 is how much air flow the intake runners will flow. The more hp you will want the 200. Amild motor you might want the 170 for air velocity. Go for the 200 You never want to go slower.

 

What would i make with this combo.

Cam : duration @ .050. IN : 192 \ Ex. 200
Lift In: .390 ex: .390

Heads 76 cc. 160cc intake volume. 2.02 \ 1.60
8.85 :1 Compression ratio.

and i think ur wrong about that edelbrock kit. how did they make 420 horsepower with it. and ur only getting 330. or is that at the wheels?

 

I don't know about how much power you will make..........but that cam is so small........its cute. I thought mine was small at 235-240 @ .050 and .490 lift.

 

thats what im running now. i thought i was making more power. cuz i beat like stangers and **** that say that have 350 horsepower. but theres absolutly no way i have 350 horsepower with such a tiny cam and low compression.

but my car is actually fast. like i do 0-60 in 5.9 seconds.
well not fast. but fast considering :P

 

What are you 1/8th mile times...include 60' times also. I run 8.5's -8.6's on street tires with a 1.999--- 60'(best 60' times I have ever got on street tires!) 8.6's with a 2.023-- 60,' I should be around 425 hp at the motor. (just a swag, thats what the holley systemax package claims) I did some light port work on the intake runners of the holley heads.

 

i havn't run a 1\4 mile yet. so i dont know. i didn't get a chance to get out yet. id assome about 13.7 or 13.8 but i beat people that claim they run 13.2 and 13.3. and i mean they stay at my bumper the whole way.

so i mean. thats just dicking around on the street so who knows. either their lying. or my car is faster than i thought.

 

Ya I was looking over the numbers, they dont seem right, Ill play around a little and get back to ya.

Hunter