Anyone install Edlebrock aluminum heads ?

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Gears and converter may be your best improvement, but don't change that rpm intake. What is the diameter of your rear tires?
Where are you AJ?
235/60/15. I know a taller tire would help. Id like to change the rpm solely to delete the crossover to an air gap. I installed a wooden spacer and it made a huge difference in how it ran, vapor lock etc. I’m positive it would run that much better if I deleted crossover. I’m also currently working on installing a fuel separator. Fuel regulator set at 6.5 also installed.
 
i don't think you'll see any horsepower increase with the airgap. Some heat is required to vaporize your fuel for better mixing.Start up and warm up will be adversely affected with the air gap.
 
i don't think you'll see any horsepower increase with the airgap. Some heat is required to vaporize your fuel for better mixing.Start up and warm up will be adversely affected with the air gap.
I’m not looking for horsepower from the air gap. It’s the only intake that deletes crossover that I’ve found. And I’m not using tin cans, lol ! I don’t drive it in the winter. Crossovers kill performance when it’s mildly warm. It’s the main reason fuel boils in our carbureted vehicles. Amongst a few other factors. If I can improve keeping fuel cooler. It makes sense to me. It’s so bad with carbureted vehicles. The fuel starts to boil when it’s a little over 80 degrees outside. When that fuel boils over into your intake. You lose power because of flooding, poorer fuel economy, difficult starts.
 
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235/60/15. I know a taller tire would help. Id like to change the rpm solely to delete the crossover to an air gap. I installed a wooden spacer and it made a huge difference in how it ran, vapor lock etc. I’m positive it would run that much better if I deleted crossover. I’m also currently working on installing a fuel separator. Fuel regulator set at 6.5 also installed.
It seems a few of the things that you're saying are backwards to me and again not meaning to knock on you or anything like that.. with the gearing you have a taller tire is actually going to hurt you and Gary you up even worse.. I run to Edelbrock 600 on top of my dual quad tunnel ram on top of my 410 Stroker and I get way better than 6 miles per gallon that's some kind of ridiculous... I had a different cam in it or I should say a different grind on my shame Cam and it was much louder and crackled much harder and barely kept an idol.. again I go back to the cam change or I had it reground to a less aggressive profile and now it actually quieted the motor quite a bit. It's still radical don't get me wrong but not is crazy as it was... Also if you start a car that has a pretty radical exhaust in a carport or somewhere like that where you get a great Echo it's going to personify it...
 
I’m not looking for horsepower from the air gap. It’s the only intake that deletes crossover that I’ve found. And I’m not using tin cans, lol ! I don’t drive it in the winter. Crossovers kill performance when it’s mildly warm. It’s the main reason fuel boils in our carbureted vehicles. Amongst a few other factors. If I can improve keeping fuel cooler. It makes sense to me. It’s sol bad with carbureted vehicles. The fuel starts to boil when it’s a little over 80 degrees outside. When that fuel boils over into your intake. You lose power because of flooding, poorer fuel economy, difficult starts.
Cool you have a garage and you don't drive it during the winter..
 
Cool you have a garage and you don't drive it during the winter..
Yeah buddy. I suffered for a very long time though. Worked on my back on top of rocks, cold ground,etc. Nowhere to work on or protect my valuables, etc. for a lot of years. It’s the only thing I wanted in life, a garage. Lol ! Just built a nice 24x36 last spring. Had I only insulated it, lol !
 
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Boiling fuel in your intake can be caused by a number of things like inadequate cooling system, lean mixture, poorly vented engine bay or more than likely timing and tune.
Not enough advance will cause the fire to be still burning in the cylinder heads and exhaust instead of the cylinder.Headers can cause excessive engine bay heat.
But a lot of guys do use an air gap style intake.
 
It seems a few of the things that you're saying are backwards to me and again not meaning to knock on you or anything like that.. with the gearing you have a taller tire is actually going to hurt you and Gary you up even worse.. I run to Edelbrock 600 on top of my dual quad tunnel ram on top of my 410 Stroker and I get way better than 6 miles per gallon that's some kind of ridiculous... I had a different cam in it or I should say a different grind on my shame Cam and it was much louder and crackled much harder and barely kept an idol.. again I go back to the cam change or I had it reground to a less aggressive profile and now it actually quieted the motor quite a bit. It's still radical don't get me wrong but not is crazy as it was... Also if you start a car that has a pretty radical exhaust in a carport or somewhere like that where you get a great Echo it's going to personify it...
I agree with what you said. I didn’t say I was getting 6 mpg. I said a guy down the street with a 360 stroker was. I know a taller tire improves top end speed or lowers top end rpm’s at the same speeds. I know higher gearing kills power, torque, etc. I said I like higher gearing because I drive a lot of high speed interstates and that’s why I never had a problem with a 2.94 in my car. But, yes. I did say I’m looking for a tad more power even though my engine runs very well and I agreed that a lower gear like a 3.23 would give me that little extra zip I’m looking for. But, it’s going to kill my 70 mph cruising speeds at low rpms, I like.
A taller tire, combined with one gear lower would be a good combo to kind of balance what I’m looking for without killing other things I like. I will have better acceleration at lower speeds and the taller tire should help a little in killing the lower rpms at 70 mph cruising speeds that I like the 3.23 will create. It’s tough to balance these cars being they have no overdrive. I like low rpms as possible at 60-70 cruising speeds ( gas mileage and comfort) But, Im also looking for more acceleration from low to mid speeds. It’s nearly impossible to have the best of all worlds. I understand to get what you want in a old street car. You have to sacrifice something. To gain elsewhere. A good street car is well balanced in my opinion. Old cars you have to sacrifice something, to get what you want. It’s not that way with modern cars, as much. They are well rounded.
 
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I might have a solution for you if you are using an automatic...but there will be some cost.
Build an early 904 with the later lock up transmission internals.This will give you a noticeably lower 1st and 2nd gear, 5 band clutch but still 1:1 final ratio.
Your first and second gears will give you the acceleration of 3:30:1 rear gear ratio but your final drive will be be your preferred 2.94:1
This is becoming a common build for the quarter milers too.
 
If you do a compression test you could get and idea about what direction to go. If you have dished pistons or pistons down in the bore you will see a low cranking pressure. If you only have 120 pounds of compression you will want to get that up. But if you have 165 or more you won't want to go much higher with iron heads. If you are changing to aluminum heads you need your cylinder pressure up to make power due to the heat transfer. Heat=Pressure=power.
'
 
I might have a solution for you if you are using an automatic...but there will be some cost.
Build an early 904 with the later lock up transmission internals.This will give you a noticeably lower 1st and 2nd gear, 5 band clutch but still 1:1 final ratio.
Your first and second gears will give you the acceleration of 3:30:1 rear gear ratio but your final drive will be be your preferred 2.94:1
This is becoming a common build for the quarter milers too.
Sounds good. Yes, I have an automatic with a 904. I’m not in favor of swapping it to another type of tranny. If I can look into what you said. Using my exact tranny. I’m all ears. Any write-ups, etc that you can direct me to ? This is not A body. It’s a B. I like this site in reference to small blocks. Because nearly all A body’s have them. You guys would seem to have more familiarity with small blocks. Compared to B body guys. More B body cars are big block equipped.
 
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If you do a compression test you could get and idea about what direction to go. If you have dished pistons or pistons down in the bore you will see a low cranking pressure. If you only have 120 pounds of compression you will want to get that up. But if you have 165 or more you won't want to go much higher with iron heads. If you are changing to aluminum heads you need your cylinder pressure up to make power due to the heat transfer. Heat=Pressure=power.
'
That was my same thinking all along. If I have lower compression as you stated. Which would not be surprising to me. I believed lower combustion chamber aluminum heads would work for me as long as the valves had no threat of hitting the pistons. Which, if I didn’t change the cam to a higher lift and a piston with a taller crown it would be ok. But, maybe I’m wrong. I’ll take the advice from those who know more about what I was logically thinking.
I intended to do a compression test very soon. But, I’m waiting to get a fuel gauge sorted before I can put tank back on in order to warm engine for a proper test.
 
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Any quality transmission shop should be able to do this for you or give you all the necessary info.
I am making this very change to my Dart this winter....and am also going to instal 2.94 rear gears. Mine was done locally.
 
Any quality transmission shop should be able to do this for you or give you all the necessary info.
I am making this very change to my Dart this winter....and am also going to instal 2.94 rear gears. Mine was done locally.
Thank you, I have a very reputable transmission shop out the road. The shop has been there for probably 40-50 years. If it can be done to mine, they’ll know. I ll look into it.
 
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Any quality transmission shop should be able to do this for you or give you all the necessary info.
I am making this very change to my Dart this winter....and am also going to instal 2.94 rear gears. Mine was done locally.
What year is your 904 ?
 
I agree with what you said. I didn’t say I was getting 6 mpg. I said a guy down the street with a 360 stroker was. I know a taller tire improves top end speed or lowers top end rpm’s at the same speeds. I know higher gearing kills power, torque, etc. I said I like higher gearing because I drive a lot of high speed interstates and that’s why I never had a problem with a 2.94 in my car. But, yes. I did say I’m looking for a tad more power even though my engine runs very well and I agreed that a lower gear like a 3.23 would give me that little extra zip I’m looking for. But, it’s going to kill my 70 mph cruising speeds at low rpms, I like.
A taller tire, combined with one gear lower would be a good combo to kind of balance what I’m looking for without killing other things I like. I will have better acceleration at lower speeds and the taller tire should help a little in killing the lower rpms at 70 mph cruising speeds that I like the 3.23 will create. It’s tough to balance these cars being they have no overdrive. I like low rpms as possible at 60-70 cruising speeds ( gas mileage and comfort) But, Im also looking for more acceleration from low to mid speeds. It’s nearly impossible to have the best of all worlds. I understand to get what you want in a old street car. You have to sacrifice something. To gain elsewhere. A good street car is well balanced in my opinion. Old cars you have to sacrifice something, to get what you want. It’s not that way with modern cars, as much. They are well rounded.
I was referring to the guy with the 360 Stroker which turns it into a 408 and that's .030 with a 4-inch crank.. mine is .040 with a 4-inch crank and it makes it a 410 Stroker.. I was calling out your neighbor's gas mileage in the fact that I run to four barrels on top of that and get way better gas mileage that is just likey an offhand comment or a little bench racing talk..
If you got a taller Tire and a 323 gear they would theoretically try to cancel each other out..
again not trying to talk you into a stroker or anything like that but that again is why I was saying people like them for the street.. you don't have to put a crazy aggressive cam like your neighbor does.. all that low-end torque allows you to run that kind of gear you want and still have that feeling that you like when you step on the loud pedal...
 
Also there's the idea of getting a transmission out of a mid-90s 2 wheel drive Dakota.. aka an over Drive transmission...
This would theoretically allow you to run a 3: 55 or even more aggressive gear and still have your overdrive for the freeway...
 
Also there's the idea of getting a transmission out of a mid-90s 2 wheel drive Dakota.. aka an over Drive transmission...
This would theoretically allow you to run a 3: 55 or even more aggressive gear and still have your overdrive for the freeway...
My mistake. If would love to stroke my 360. But, I’m not risking my chassis for a lot of power. I’m not sure if A body chassis are similiar to B’s. But, with B’s they have questionable areas of the chassis and body’s subject to a lot of torque. Unless these areas are addressed or in extremely good condition. Mine are very good. But, not good enough to risk.
Another huge factor is my car is a rare convertible. Convertibles are subject to body stress or cracking near the lower corners of the rear window running along the trunk and rear quarter panel. Because they weren’t designed with stress relief like hard tops. Your A body car has body stress reliefs if it’s a hard top. It’s a quarter inch slit running from the lower corner rear windshield to the trunk. Chrysler didn’t design convertibles this way. A flawed design.
I’m not in favor of changing tranny models from a different era due to cross member fabrication and floor gutting. It’s a pretty rare car.
 
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Gears and converter may be your best improvement, but don't change that rpm intake. What is the diameter of your rear tires?
Where are you AJ?
I was waiting for someone to ask about the convertor and gearing, cuz you know gearing and stall is paramount to a streeter. And also talk about cylinder pressure.

My opinion is this; the best you can get, reliably, with 63cc heads and zero deck is about 10.8 Scr, and when you switch to aluminum from iron, yur gonna need about an extra full 1.0 Scr just to make the same power that you were making with the iron. I know smarter men than me will argue this, but the dyno ain't the street.
If that is true, then for the aluminum heads to break even on material alone, then your current combo would need to be at least 9.8Scr right now. So if yur still at 8/1 this is a lost cause, and so spending big bucks on aluminum to gain the compression is a waste of money, even if your current Scr was 9.8
Further more
if you did have 9.8 with IRON, and did pump it up to make 10.8 still with IRON, and made no other changes, then you could expect a power increase of just 1.5% or so. Now recall that the power increase comes at high rpm and is over a very narrow rpm range. This reflects nothing on what is going on at sub-peak rpms.

Ok so now lets say, for argument's sake that you currently have about 300 hp and it's peaking at 4800rpm. With 2.94 gears,26" tires,and 5% slip in the TC, this will be ........................ 49mph. The power will begin at about when the torque peaks, so in this case about 3300 ........... at 34 mph.You see the problem? You got a lotta driving to do to get onto the bottom of the powerband, and a lot more to get to the peak.
This makes the engine SEEM weaker than it is.
Next is the current TC which you don't know much about, so let's be generous and call it a 2200 stall. So when you punch it from a stop, the Rs will rev up to 2200. If you imagine your torque curve, you might see 220 ftlbs there. So, to the road, this would be
220x2.45(1st gear)x2.94(rear gear) is 1585 ftlbs into the rear axles which is barely enough to squawk the tires , am I right?
But by 3000 you'd be coming up to the torque peak, so if you had a 3000 TC and if your engine was making 300ftlbs there, and say you had the 3.23s, then
300x2.45x3.23=2374 ftlbs which is 50% more torque into the axles. Fifty per cent more!
Same engine.
I'm guessing at the numbers for illustrative purposes but your results could be similar.
The 3.23s will bring 3300 down to 31 mph (from 34), and down to 45 (from 49). still not really impressive, but what can you do when hiway cruising takes precedence...
As can be seen, the bigger TC makes a huge difference;and in your case the TC is the first thing I would change;Say a 2800. This will make a huge difference in the personality of first gear. The 3.23s will make subsequent gears feel 10% stronger, but you will be spinning thru most of first gear now,so the 3.23s might get lost in the tiresmoke.

And my opinion is to not be in a hurry to change the cam. With no other changes, a later-closing intake valve will make less cylinder pressure, and you will feel this as a loss of power in the lower rpms from stall to torque-peak .............. exactly what you don't want, with the stock TC and 2.94s. More power at some much higher rpm is probably not what you want.
These are my opinions.

Now, if you really want to wake that engine up, get you something like 3.91s .............. but forget about daily hiway cruising, cuz 65~3300 at zero-slip. There's no free lunch. If 3300 is to much, get you an overdrive. The A500 will get you a .69od gear, reducing 3300 to 2280 in lock-up.
And still same engine.

When yur ready for more power, the very first thing that you gotta do, for your combo, is to pump up the pressure. Not for the horsepower at higher rpm, put to make that engine jump off-the line, cuz that is how I interpret your power comments. You don't much care about power at 5000rpm. You care about acceleration off the line and getting her up to hiway speed.
After the TC and gears have been selected, your only other options for this, is more low-rpm airflow; which leads to cubic inches and/or cylinder pressure/or supercharging. I think new pistons is probably the cheapest.... but likely also the least bang for the buck. A stroker will get you more bottom end than you can use, but it sure would be fun.

With a 360, you can easily build power in any rpm range you can think of; but it's still only a 360, and if you hog-tie it with hiway gears, there is only so much you can do.
With a limited displacement, the best idea of all is an overdrive, in conjunction with a big performance gear in the back.
Suppose you wanted to continue your current rpm@70, but installed the A500/518, with it's .69 overdrive. This would allow you to select a rear gear of up to ; 2.94/.69=4.26 , rounds to 4.30s. which points to 4.30/2.94=plus 46% more TM (Torque-Multiplication), which will instantly make your combo seem like it was 46%more powerful ............ right thru the rev range from stall to shift. And still same engine. Besides supercharging,No other changes to your engine can match this. NONE.
Then, if you choose an A500, then you get the bonus TM that the ratios bring, namely 2.74-1.54-1.00, as compared to the 904 having 2.45-1.45-1.00.
Of course, you don't have to run 4.30s. 3.91s is only 10 % less impressive, and you get the bonus of 10% less rpm on the hiway than you are currently doing, namely 2440 in loc-up, versus 2660 at zero-slip, both at 70mph.
With the A500/3.91s your starter gear is 3.91x2.74=10.71, versus 2.94x2.45=7.20 currently, a difference of 49% again! Turning your possible current 200ftlbs@2200rpm, into 200x10.71=2142 ftlbs before the TC is factored in, compared to 200x7.20=1440 currently.
I can tell you that the A500/3.91 combo will knock yur sox off...........
still with the same engine.

BTW,IMO, installing an AG to block the crossover because you don't like the tin-can (which is actually a stainless steel insert) idea is like stepping over a dollar to pick up a copper. That crossover is 100% inactive after you shut the engine down, so cannot be the source of your boiling after shut-down. Also at your power level, and rpm, running without that cross-over is not gonna get you much, except maybe less fuel mileage.
If anything, give that engine some cool fresh air, install a big aluminum deflector plate under the 4bbl, and retune for that.
Does the AG run cooler? Sure. But when you shut the engine off, the heat comes up and there is nothing you can do about that, except maybe ventilate the hood. Don't laugh, I did that, and have zero boiling issues. Yes I do have an AG, but my engine needs it. And she runs a 750Holley DP, bolted on with no spacer, and I run my engine at 207*F. And she turns a 4-speed so she's always reving.
So what I'm suggesting is to look closer to home, for a cure to boiling after shut-down. My opinion.
Sheesh, another novel.............
 
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My mistake. If would love to stroke my 360. But, I’m not risking my chassis for a lot of power. I’m not sure if A body chassis are similiar to B’s. But, with B’s they have questionable areas of the chassis and body’s subject to a lot of torque. Unless these areas are addressed or in extremely good condition. Mine are very good. But, not good enough to risk.
Another huge factor is my car is a rare convertible. Convertibles are subject to body stress or cracking near the lower corners of the rear window running along the trunk and rear quarter panel. Because they weren’t designed with stress relief like hard tops. Your A body car has body stress reliefs if it’s a hard top. It’s a quarter inch slit running from the lower corner rear windshield to the trunk. Chrysler didn’t design convertibles this way. A designed flaw.
I’m not in favor of changing tranny models due to cross member fabrication and floor gutting. It’s a pretty rare car.
LOL.. again I wasn't suggesting a stroker with a hot cam that's going to twist your body..lol.. they do make frame connectors and all kinds of stuff to stiffen the frame.. I'm pretty sure the transmission I mentioned wouldn't be so custom you'd have to cut your tunnel.. I could be wrong but I just haven't heard of it.. now someone trying to put a modern Hemi with a modern transmission yes for sure...
 
^^^ also if you're able to make it through everything AJ says in his book long response you're better than most...
 
I believe my 904 is a '72
Thank you, my engine is a 72. But, tranny is a 69. More than likely will work for me the same. My guy will know. Your suggestion may be perfect as I have to address another small tranny issue. Can kill two birds, with one stone. What was your estimated cost, if you don’t mind me asking ?
 
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Thank you, my engine is a 72. But, tranny is a 69. More thank likely will work for me the same. My guy will know. Your suggestion may be perfect as I have to address another small tranny issue. Can kill two birds, with one stone. What was your estimated cost, if you don’t mind me asking ?


You don't need to change intakes to block off the heat. They make gaskets for it. Are they perfect? No. Do they work? Yes.

I'd have been doing that today. No reason for all that heat under the carb. It's dumb really. You can do much more with booster gain and tune up without using red hot exhaust gases.

Unless you have a Carter type carb. I don't know if you can even get an aftermarket booster for that carb.
 
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