I need some help from some of you engine guys. I need some advice on choosing a cam and a converter stall speed. here's the deets so far.
302 block
bored .30 over
stock crank / rods
Speed Pro Hypo pistons
Ported E7TE iron heads
Weiand Stealth dual plane intake (1500-6800)
650 DP Holley
Stock distributor Accel Coil, MSD 6AL module
Long tube headers
Transmission is in the shop right now getting rebuilt. It's a C4 auto and it's getting heavier duty components, a shift kit and a manual valve body.
The rear is an 8" with a mini spool and 3.80:1 gear ratio.
Rear tires are 295/50/15 which are about 25 1/2" tall.
The car is going to be a street / weekend drag machine. Occasional drive on the street for fun. Revs to no more than 6000rpm expected.
I'd like to know a good cam / converter stall speed choice that will work with what I already have. I emailed Comp cams and they recomended the FW XE284H-10 which is 0.541 lift/284 duration on the intake, 0.544 lift/296 on the exhaust and 110 lobe seperation, if i went with a 2800 stall speed.
I know absolutely notta about cam specs, or how it works with converter stall speed. All I know is that I was told that the cam and converter should match for best results.
You guys have any advice?
MrPinto,
Well...That is an awefull lot of cam for the street. And the link that doesn't compute is the stock rods. I would suggest something in the 300's for lift and reduce the carb size to a 600. This is based on the word street.
High_Horse
Quote from: High_Horse on July 04, 2007, 04:39:55 PM
MrPinto,
Well...That is an awefull lot of cam for the street. And the link that doesn't compute is the stock rods. I would suggest something in the 300's for lift and reduce the carb size to a 600. This is based on the word street.
High_Horse
I was told once I had the rods shot peened and larger studs pressed in they would easily handle moderate power.
???
Peening doesn't strengthen rods it relieves any potential stress points kind of like a metalergical balancing. It is a good reliability measure. .500 lift is not moderate for the street, 300 is moderate and the carb suggestion was just to allow for a good non fouling idle. I ( and this is just my opinion) look at the line between street and strip as being at about the 100 mph mark. 100 on the street is fast. I've seen alott of engine builds and people just seem to overcam for the street and then they regret it. Don't get me wrong....they sound good. 2800 sounds right for a 500 lift.
High_Horse
My 68 Cougar's engine,351W, had the following-
.472 int .496 ex lift, 214deg@.050 int and 224deg@.050 exh. The Ford Motorsport number is M6250-a332. This is made for Motorsport by SpeedPro, I believe, as they have the same specs.The m6250-a351 is a real strong street cam also, which I ran. I ran Speedpro hypers as well (H336.030) with ported D0OE heads- it was damn strong- ripped tires going through all four gears (toploader, 8inch rear w/3.80:1 and 14inch tires). Highway @65mph was around 3200rpm
The Cougar is a good 1000lbs heavier than a Pinto (with a 4banger, anyways) I think the above cams are by far the way to go- using the fore-mentioned mfg's also. Step away from Comp Cams, yes they make a nice product but you will pay a helluva lot more than a Speed Pro cam- and they make real nice stuff too.
Have fun! Building performance engines is better than sex! :evil:
I am in the process of building a 347 stroker. This is the first Ford I have built in sometime however. The last cam I ran in my v8 vega was actually a lil to big for the prurpose and I never did ge tit to run like I wanted and had No vascuum and the low end sucked. It was a .510/.533 lift and I had a 3500 stall.
I am going to go with a Summitt cam that I ran and really liked it is a .488/.488 and ran out great of the line and up to about 6k. Those Big lift cams SOUND great rumbling thru the exhaust but no heavier than these pinto's are it doesn't take alot. I am hoping to push about 450hp out of this stroker. I seen where Edelbrock has a NEW intake for a 302 that is an Air Gap and set up for 2 4 barrels. I am going with that and see what happens.
I believe that a split cam profile is best on the Ford engine- particularly the small blocks. The exhaust port is damn restrictive- even with porting. Personally, I have never thought .496I .520e and .520i .538e lift to be big lift. Besides, vac issues are generally caused by overlap, with duration contributing some.
My Cougar, thankfully, was manual trans with man. brakes and man.steering. Do yourself a favor (unless you are competitively drag racing,) Go wit the manual trans and no power options if possible- and then the sky is the limit (kinda) for cam specs.
As you have seen, when asking about engine building tips, there are many varying opinions that can cause you more problems than help. The best thing may be to find a really good engine builder (ask others in your area about their experiences and reputations) in your area and talk to them. I spent some time "working" at a performance engine shop, and have seen many poorly planned engines show up in order to be "straightened out." The best policy is to take your time and do LOTS of research before buying.
I once was told by an "old-timer" that when picking a cam stay on the conservative side, "you'll be happier.". My very first engine was built using his thought- it wasn't long before I had a bigger cam ordered. Once in place, I was much happier. Save being conservative for your political thought- liberal is the way to go with power building- just do it in a very deliberate and informed manner- RESEARCH IS THE ORDER OF THE DAY!
Redeless, where do I find the SpeedPro cams? Summit Jeg's etc doesn't list them.
Check at your local parts stores, particularly the ones that deal with your local installers/service shop professionals. Also, if you have an engine builder/machine shop in the area you may want to speak to them. Speed-Pro is/was a Federal Mogul brand- a company that was fraught with financial problems. I would not be surprised if Speed-Pro was sold off. If so, you still have the Ford Motorsport cams, which always had the exact same cam specs as the Speed-Pro.
As I stated before, some research (which I think is the funnest part of the process) can save lots of cash. Performance parts can often be sourced from your machine shops at prices that are just as good or better than Jegs or Summit- without shipping!
...performance engine building is better than sex. A woman that likes to build performance engines during sex- man, it just couldn't get any better! :lol: