street/daily driven heads

[bart]

whats a good head for a daily and street driven application? not goin to school this summer so i can have some down time, figured id go with some heads, since thats about all i lack n/a wise. im lookin for something with some killer bottom end. i dont have a high winding motor, well at least i dont really do it. i do alot of the dead stop and 30 punches. i currently have iron gt-40s with .020 knocked off of em. gt-40 intake and an e-cam. id like to do aluminums, then again id like to find some other iron gt-40s and send them off to thumper. worse comes to worse ill yank mine off and send them to him. im just lookin for opinions and ideas here so i can be getting things lined up beforehand. i have a set of e7s here but, i know that i can send my 40s instead and theyll still be better afterwards compared to e7s.

id just like some ideas opinions advice and whatnot. thanx in advance. also this is w/an aod and 3.73s

 

[bart]

anybody?

 

[Michael Yount]

If you're lookin' for killer bottom end, keep what you've got. The more you open them up, generally the more they'll flow up top, and the worse your low speed velocity will be taking bottom end with it. You can't have both without more displacement or boost.

 

[bart]

If you're lookin' for killer bottom end, keep what you've got. The more you open them up, generally the more they'll flow up top, and the worse your low speed velocity will be taking bottom end with it. You can't have both without more displacement or boost.

well hrmmm, will changing/porting them though give more power? like will it bring the seat of the pants feel back? i guess i said that wrong, i need my power to be in the low speeds.....i guess thats a good way to say it. obviously my foots gonna be on the mat, when im doin this, so i guess it really doesnt matter. mainly, mine has gotten "slow" on me and im ready to bump up to the next stage. some of my friends have driven it and come back and said i was crazy and that its fast, but im used to it, plus id like to get in the lower 8s (we have an 1/8th)

 

[Michael Yount]

Opening up the heads so they'll flow more should allow more power IF your heads are the bottleneck to flow on the engine. The other issue to consider is where you want the power torque. Usually as the flow potential of the engine increases - it will support more rpm/more flow/more power. But unless you're really careful, as that flow/power/rpm potential increases - you're shifting the power band higher in the rev range - which means the bottom end is getting softer. Your peak power and torque numbers may increase, but the amount of power and torque you're making at lower rpm (say below 3000) will decrease. On the race track - that's not a problem. But it can make for a street car that's not as much fun to drive day in and out as most time on the street is spent in the lower part of the rev range.

 

[Michael Yount]

If you want an aluminum head that will perform similarly to what you've got now - the GT40Y303 heads flow a bit better than the irons, but will knock about 50 lbs. off the front of the car. But, if you're lookin' for improvements, it'd be hard to argue with the results of putting a set of AFR165's on there, or the new edelbrocks. Either set should show a big improvement over your iron GT40's in terms of peak power.

 

[bart]

ok, well i drive to school 5 days a week, 104 mile round trip, bout 95 of em are pure highway. mostly 75-80 mph. when im in town, i play alot, if the night is good. mainly i just want the seat of the pants feel back, ive been told theres 3 ways (except nos), heads, SC and 4.10s. dont really want to drop the 3.73s.

alot of the guys that i know run eddy performers and theyve been tellin me to go with alum heads. ive just got to get it set in my head. is it common that alum heads can make street drivin not that fun?

 

[Michael Yount]

"is it common that alum heads can make street drivin not that fun?"

Your statement is absolutely not true. It's the overall package that makes or breaks a car for a given application. Not just one component. It's how heads/intake/exhaust/cam/tranny/gears all work together that make one fun or not so fun on the street or track. If you're looking for a noticeable bang on top while not sacrificing any drivability, throw a low boost supercharger on it. You'll see a big hit of HP up top, with solid gains in the midrange as well. As soon as it starts making boost, power picks up.

 

[bart]

ok, well as long as its not a thing that is gonna aggrevate me.

my mods are a CAI, 77m pro-m, 65mm tb, explorer upper and lower, e-cam, i have 1.6 rollers on my heads right now which id probabaly just swap over, hooker LT's, o/r h-pipe and 2 non delta 40s. the aod has a transgo hp kit and i have 3.73s out back. my car is the same motor minus heads that most of my friends have, but most of them are 5-speed, and one of em is an auto also. does it sound like ill be ok with alum heads, with what i have goin on so far?

 

[Michael Yount]

Like I said - depends on the combination. There are a BUNCH of different aluminum heads available out there. Roush, Canfield, Brodix, several different sizes from AFR, TFS, Edelbrock and Ford Racing off the top of my head - and they all have different flow characteristics, some have different size valves, different arrangements for rockers (some stud-some pedestal), some geared for the street, some for racing, some for higher rpm, etc. So you see "aluminum heads" doesn't just mean one thing. I'm not sure what's "gonna aggrevate" you -- I'd get some more clarity on exactly what it is you're trying to accomplish with your next change. What you want to happen, and what you don't want to happen.

 

[thumper460]

You can advance the E cam to 106 intake center line ( 4* advanced) and that WILL give the low end back!! Michael is right on port work!! But I think he is trying to say "port HOG work " !! If you open alot... like he says, the top will increase at a loss on the low end!! (same with big aftermarket heads or camshaft) But the proper port work ( to keep the smaller runners for high velocity) and the most critical "proper valve job" will increase the power thru ALL ranges!! SOOoo... bump the cam up for now and get the heads done ! and the AOD will rock!!

Just me.......................

Thumper

 

[357f-150]

When I read your original post, then your list of modifications, my initial thought was go with a higher stall torque converter.





357f-150

 

[bart]

Like I said - depends on the combination. There are a BUNCH of different aluminum heads available out there. Roush, Canfield, Brodix, several different sizes from AFR, TFS, Edelbrock and Ford Racing off the top of my head - and they all have different flow characteristics, some have different size valves, different arrangements for rockers (some stud-some pedestal), some geared for the street, some for racing, some for higher rpm, etc. So you see "aluminum heads" doesn't just mean one thing. I'm not sure what's "gonna aggrevate" you -- I'd get some more clarity on exactly what it is you're trying to accomplish with your next change. What you want to happen, and what you don't want to happen.

well i have a few friends whove done too much to their cars. Jake for example has a chevelle that is just nasty, but its not suited for street driving at all. me and him can go froma dead stop, i can walk off and leave him and about a mile down the road, he'll blow past me. his car is fun on the interstate but it sux below 60mph. mainly what would aggrevate me is something like that. i want it to be strong and fast, but i want it to be easily streetable. a good low speed runner, i dont care if its top speed is 100. we dont a 1/4 anywhere close around here anyways. i just want a nasty street driven car thats gonna be awesome when i put my foot on the mat, whether im at 15, 30, 45 or a dead stop. and yes i do need to bump up the stall too sometime, my 2400 went to around a 13-1500 when i did all that stuff.

mike, youll port my 40s if i yank em off and send em to ya? personally id RATHER have mine ported, i can see at least a 400 dollar savings by doin that.

 

[Michael Yount]

Bart - Thumper knows his stuff - if you are clear what you want and don't want, he can help you get there. The only thing I'd add - and he and I may see this a bit differently - I'd say advancing the Ecam will get SOME low end back; I wouldn't say it would get THE low end back.