No doubt. The questioner of this should just simply sell or put the intake up for trade.
If the LA head can be redrilled as to accept Magnum intake I don’t know and I would never bother to find out if it could be done.
Aluminum cylinder heads
- Thread starter Dan the man
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If the LA head can be redrilled as to accept Magnum intake I don’t know and I would never bother to find out if it could be done.
Dan the man
Well-Known Member
Awesome, I will do that
Dan the man
Well-Known Member
I was going to ask about what would be a decent ignition timing to run and if I could run a timing limiter, but I don't think that would be a good idea for me to do so.
Why?
Ironracer
Gearhead
That would depend on yer set-up
Dan the man
Well-Known Member
I thought about using the mopar distributor with a gm 4 pin control module with the correct coil.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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IMO
as usual
you will never be sorry if you go alloy.
But
one of the best ways to get the most out of them, is to pump up the cylinder pressure ........ because
you can and should; on account of their excellent resistance to detonation. With a 318, getting in the neighborhood of 11:1 or more, is a bit of a challenge, as the cam's ICA grows ever later. Pistons are the problem.
IMO, to date, this is by far, the best idea you have had. The high cylinder pressure opens the door to so many advantages; Power, Torque, economy, a very low cruise-rpm, excellent throttle response that is almost guaranteed to pucker you pooper, the ability to run the lowest octane gas at least most of the time, and more.
Alloy heads, in the right combo, will help your 318 get to the next level in performance, while simultaneously increasing your fuel-economy, and shedding the "old-retired-guy/tread lightly cuz I'm done" nature, of the lowly 318.
Sure you can achieve similar results with closed-chamber iron heads, but probably not on 87 gas. And at the price of gas today and into the future, this is gonna become a serious concern. The savings in fuel costs alone are pretty significant. And so is a 20 or 30 percent increase in mpgs. IDK the price of your fuel down there but lets say you pay 6.50 a USg for 87 and plus 12% for 89 and plus 24% from 87 to 91. The numbers might be off but the percent difference should be accurate.
Say you drive your low-compression 318, 6000 straight hi-way miles in a year and typically a 318 A-body gets 20mpg. that will cost you 300 gallons of 87 gas equals $1950.
If you modify that unit with iron heads, and have to run 91gas@WOT, but now she only gets 18mpg due to loss of effective compression,etc, then you are looking at $2690
But if you install alloy heads, and pump up the effective compression, and now she gets 24mpg on 87, your costs drop to 1625.
But wait, now you are primed for an overdrive, and say the mileage jumps to 27; now yer looking at $1440.
So in a year, the theory is to save the difference from 2690 to 1440, and I get $1250.
If you spend $5000 on the alloy heads/valve gear and the A500, and NOTHING on gears or TC, cuz your hi-compression 318 pulls any gear at all, what's the pay-back period?
I get 4 years.
After that, yur still saving 510 per year, until you need a valve job, lol..
And during the which, your power-increase is soooooooo much fun. When you plant your right foot and stuff actually happens at the back tires, it's like;
"yeah baby, shower-time!".
I have run 185psi and more on 87E10. Other FABO members claim 200 on best gas. My current combo is a tic under 180. If I ever get an opportunity to do it again, I will target 190 or better.
Now, recall that the numbers I used are straight from my imagination, but the differences between them are proportional, so, by percent, they could still be meaningful. AND
My Eddies have over 100,000 MILES on them, and are still going strong. In terms of Dollars, those heads payed for themselves many many years ago. In terms of fun, I loved the significant cylinder pressure possible, right from the first time I ever nailed the gas!
So if there is one thing I can tell you, it is this;
with alloy heads; FORGET 9.5Scr, it is meaningless. Forget 10/1, and also forget 11/1.......... The thing that is important is your EFFECTIVE cylinder pressure, which starts with knowing your cranking cylinder pressure. And you cannot know that until the cam is installed. But you can use all those numbers in a Dynamic Compression Calculator, to get pretty close. I use the Wallace Performance one.
Wallace Racing: Dynamic Compression Ratio Calculator
Dan the man
Well-Known Member
I don't want to aggravate anybody
Scody21
Just send it
Have ya even had a machinist look at your heads? I had a set last summer done for around 500 or 600 bucks, I bought springs, and a few valves as most cleaned up just fine, assembled, and lapped the valves after our machinist put in new seats, cut the seats and decked it.
In your own words, “it’s a cruiser”. Keep it stock and put a cam in it and call it a day.
Stop looking at hot rod parts! Your mind is getting polluted with all this unnecessary stuff…
In your own words, “it’s a cruiser”. Keep it stock and put a cam in it and call it a day.
Stop looking at hot rod parts! Your mind is getting polluted with all this unnecessary stuff…
I don’t fully understand that comment connected with the quote above it but to answer what I quoted from you, my answer is “To late!” LMAO
Carry on Dan!
100% what he said! ^^^^^^^
Dan the man
Well-Known Member
I really believe that's the best way for me to go, not to over think it
Dan the man
Well-Known Member
What would be a good ignition timing to start with? 10*? Limiter plate
Scody21
Just send it
depends on the distro and cam. This how your motor runs. Need to find someone that can help you tune.
Dan the man
Well-Known Member
There is a high performance shop not far from where I live, I think that I'll get in contact with them
Dan the man
Well-Known Member
Even though I don't have plans at this time for a cam change, I'm wondering if it would be a good idea to check out the condition of the timing chain and perhaps replace the harmonic balancer
There is a guy makes a conversion kit for your stock Mopar dizzy to accept the GM module. I bought one and never used it.. sitting on shelf in garage.
Looks like this:
The timing lock out plates are fairly easy to get.. who is it makes' em?? FBO? Think you can gettem through Mancini.
Anyway.. I scrapped all that and went with a straight up HEI Dizzy I picked up on Ebay. Replaced the module and coil with Petronix Flamethrower 3 parts and never looked back.
My2c.
The K.I.S.S method is best for new guys starting out in any type of hot rodding.
Keep
It
Stupidly
Simple
To start, IF the engine is in the car, just get it running.
Now IF you he engine is on a stand, I would simply purchase replacement parts and replace them.
Nominally speaking, yes. But I’ll hat “Also depends” on a few things that will be covered when you get it all together.
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You can also do like my Dad and I are doing on his Magnum engine. We are dumping the heads for LA heads and using the roller rocker kit from Mancini that oils through the pushrods.
Ironracer
Gearhead
It is addictive. "How much junk can I put in here to make it go Faster and still be Streetable and Reliable" hmmmm
Scody21
Just send it
Oh yeah I know this, I don’t even want to think about how much Ive spent my bucket o bolts…
Ironracer
Gearhead
All I know is for what stuff costs today, I'm done. Unless I can score a cam for that 440 out back, and an ol truck... or something cheap, and I doubt that will happen. My business is getting killed with Bidenomics... so it's just me an the 340 A body now. Thank God i already built the mill 12 years ago, and I finished buying most everything the car needed as soon as this covid bs started
I just received that rocker kit in the mail the other day. Now I’m just waiting for a deal on a decent set of heads…
Dan the man
Well-Known Member
Is it true that the gm hei distributor has clearance issues with the hood and the firewall ?
Dan the man
Well-Known Member
Car does run, I was just trying to plan out on how to improve the overall performance
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