67mustang302

They prolly dyno it without accessories, run the ol electric dyno water pump and power the ignition from another source. Not having to turn accessories can make quite a bit of difference. I'm sure all those companies have their little tricks to get the paper power output.

eZ

67mustang302...very good info thank you...if i run 165's with the same cam will that give me better low end or is the cam too much?

mjr46...did you run that in your classic? what year, motor etc.?

dirtydave289

By streetability you mean how much get-up-and-go the engine's got?

Starfury

The cam and the heads both make a big impact. The combination of the cam's large amount of valve overlap and the relatively large ports in the heads contribute to low vacuum and low port velocity at lower rpm's, reducing torque and throttle response. Both are designed to operate at a higher rpm for that engine, and they do, but they sacrifice low-end drivability.

A set of 165 heads and a milder cam would be a much better combo for a street driven 302.

eZ

like the one putting out 402 hp?

mjr46

No, I ran it in my 85 gt IT WAS A 92 ROLLER BLOCK bored .030 with .200 dome kb pistons , afr 185's with upgraded studs and springs a comp cam xe282 hr cam .565./ .574 and rpm air gap intake and 650 double pumper carb and off course all supporting mods like long tubes, exhaust, elec water pump and fan, and gears ect ect........and motor was balanced.....the build yielded grat power and it ran with and faster than some 331/ 347 stroker motors on efi cars alot of people I knew were at or around the 107 -109 range and 12.50 to 12.60's on their stroker applications so when I beat them they were suprised I only had a 306..... but it's all in the combo..match the parts as I tried to do and it worked well......unfortunately all good things come to an end and it's out of the car right now waiting the arrival of a 347......Nos wasted my bearings so to fix the bottom end it was 1400 vs 1800 for a stroker short block so I'm not reusing mycurrent short block I will however fix it as it only has5000 miles on it..maybe put it in another car as the combo performed quite well

67mustang302

I'm running the 165's with a mild Crane cam and it runs really well, it'll leave a stop light like no one's business, and it only has a 3.00 gear with a long 1st. If I had more gear and a 5spd I prolly woulda gone with at least a bigger cam and intake, maybe larger heads, but mileage would have been wrose in the city at the very least. You don't need a big cam or big heads to make good power, just a good cam and good heads with a well setup combination. I'd prefer to build a smaller headed car with a decent cam/intake etc that makes good power, then make up the rest of it at the track with juice, but have something that drives well and gets good mileage. You can build a 302 with the larger heads and cam, but you'd need more gear for it to drive aswell, and spend all the extra on the supporting stuff, plus end up spending more on gas. It comes down to what you want to spend, what you want to get and what you're willing to tolerate.

Here's something to consider though, Edelbrock has some new heads out now(new enough that you can find nothing about it on their site, except flow data for the 351W head version only). Called the Pro Port CNC, they're basically a next generation version of the Performer RPM series heads. The 289/302 version only has a 170cc port, but I'm sure flows like mad, I looked at the data for the 190cc port version, that they target at the 351W, and it outflowed even the Victor Jr heads they have that come with 220cc ports, and outflows the AFR 185's by a pretty fair margin, yet has a port roughly the same size. So I'd imagine that the Pro Port 170's flow almost as well give or take as the AFR 185's, but with a smaller port for better velocity and drivability. And it's not an exotic head design, so I imagine the price is on par with the AFR's, Darts etc. I'd look into that head if I were you, it's prolly gonna be the best bang for the buck head out there for a SBF, at least until someone designs something better with a reasonable price. Technology marches forward and all that.

eZ

ill look into that. want to do this soon because im pulling out the motor for the body and paint. thought it would be a good time to touch up the motor while the car is off to the paint shop. do they have the new heads for sale yet?

67mustang302

I'm pretty sure they do, I've seen them listed as an item on other sites, but I think they're currently only available bare.

dirtydave289

If you get those heads tell me how they work for you eZ