i was at work and i was talking about some afr heads that i might get. This dude from another trade laught and said save the money and get yours ported for now. then when you get the money do the heads, roller rockers, and cam tfs stage 1 at the same time. I never heard of porting stock heads. what do you all think of that.
porting heads???
- Thread starter oldno7
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porting e7s is a massive waste of money. If you dont want to spend the cash on a set of Alum. heads, pick up some explorer heads, port them and put new valvesprings on them.
Ported E7's can give you enough flow, to get into the 12's pretty easily, but I wouldn't really count on it if it's your first port job ever. And why spend the money on items to port them, when it could be spent towards some AFR heads, if that's what your goals are? I wouldn't waste the time on the E7's, personally.
heres the thing.
1 what here you shooting for?
2 if you have e7 already spend a couple hundred bucks and get them fully ported. (they flow better then gt-40s when there ported and i beleive they flow more than gt-40 heads in the lower lift ranges) not postive on that though.
3 if you are runnig a stock or mild cam the last thing you want to do is run a big head like a afr185 its too much you will lose your lowend and gain high end and thats not good for a daily driver. plus those heads are meant for engines with more ci than the 302. now the afr 165's are good heads and you'll still have your lowend grunt. i would port the e7s install a mild cam bigger inj and massair flow trottle body and the 2.5 ex with a h or x-pipe. and you'll be happy with it in the end without breaking the bank. and if you haven't done this already 3.73 gears are a good all around gear. good luck
1 what here you shooting for?
2 if you have e7 already spend a couple hundred bucks and get them fully ported. (they flow better then gt-40s when there ported and i beleive they flow more than gt-40 heads in the lower lift ranges) not postive on that though.
3 if you are runnig a stock or mild cam the last thing you want to do is run a big head like a afr185 its too much you will lose your lowend and gain high end and thats not good for a daily driver. plus those heads are meant for engines with more ci than the 302. now the afr 165's are good heads and you'll still have your lowend grunt. i would port the e7s install a mild cam bigger inj and massair flow trottle body and the 2.5 ex with a h or x-pipe. and you'll be happy with it in the end without breaking the bank. and if you haven't done this already 3.73 gears are a good all around gear. good luck
This is misinformation.
"Big" heads do NOT hurt low end torque. AFR 185s are NOT too big for a street driven 302, in fact, there are members on this board with AFR 185s on their 302s.
Check out this thread. We were just discussing this topic the other day. Specifically, look at the 351W in there, the guy used heads that flowed 380CFM (that's roughly 100 more CFM than AFR 185s) and the STOCK 5.0 HO cam. Damn thing made almost 400 ft-lbs to the wheels. Was already making ~330ft-lbs at 3000rpm. Did those big heads hurt his torque production? This was all on a street motor that didn't rev past 6500rpm.
That 351 is an extreme example, but it disproves the "big heads hurt low end torque" myth.
To the OP, it all depends on what your goals and budget are. A PROPERLY built aluminum headed 302 will run solid 11s, and even if you don't know what you're doing, most aluminum head combos will at least run solid 12s (assuming it's a stick car). The majority of ported iron headed cars run mid/low 13s or high 12s.
if your understood the effects of minimum cross section and port length, target port velocity, and the effects of lobe area on a combination you would not post this.
the fact is, most people think using a larger cross section head will automatically kill bottom end power. so they run a small cross section head that limits airflow, use a cam with more lobe area to make their small head run up top and kill the usable powerband. but still claim the big head makes less steam. the smaller cam with the larger heads will likely make less peak power, but the usable powerband will be everywhere.
the reason most people dont do this is because when you run a head that is on the large size cross sectionally, the window of error you can have in valve timing closes exponentially. the cam has to be right. if the head is too small pretty much any cam will work.
whats funny is you say an AFR 185 is too big for a 302, yet a lot of people dont have a single problem running a 170cc TFS TW on a 302. guess what, their minimum cross sections are so close they could almost be considered identical.
what i think is interesting is that a lot of people that think a head can be too big tend to choke their heads off with a long runner intake. if the smallest cross section of the port is in the intake, how can a 15 or 20cc difference in port volume (assuming the same port length) make that big of a difference?
the answer is, it doesnt.
as far as the AFR 185 vs a TFS head goes, put 2.02+ valve AFR on a virgin bore block, put a TFS TW on the other deck. turn the motor over on the stand and look up the cylinders. let me know what you think.
Exactly what Clement said. In very simple terms, "big" cams kill drivability, right? Lumpy idle, bucking at low RPM.
So, think about it (again, this is really oversimplifying it)-
Medium heads + mild cam = mediocre power numbers, good drivability
Medium heads + big cam = big numbers, poor drivability
Big heads + mild cam = big numbers, good drivability
