Yes
You have some many threads all over the place… thanks had no idea you have even selected a car much less had it running.
Best wishes to you and your project!
Aluminum cylinder heads
- Thread starter Dan the man
- Start date
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You have some many threads all over the place… thanks had no idea you have even selected a car much less had it running.
Best wishes to you and your project!
dartindanno
Well-Known Member
Any photos of the new ride?
Dan the man
Well-Known Member
Thanks
Dan the man
Well-Known Member
In the shop getting the ac fixed, will post pictures shortly
Dan the man
Well-Known Member
I'm looking forward to enjoying the ride
Dan the man
Well-Known Member
Just for grins I looked up the cost of promaxx heads vs. Edelbrock rpm performer heads, price difference between the two was less than a $140.00 for the set
Have you posted a picture of this car? I'd like to see it
3forty
"Raw Power"
Good!
Dan the man
Well-Known Member
Dan the man
Well-Known Member
ThanksNice car !!!
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
- Joined
- Jan 19, 2014
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If the car already runs, then,
for improved off-idle to low-speed/low-rpm, performance,
the best bang for the buck, is a higher-stall TC , and/or higher rear gears, (the 4bbl and free-flowing exhaust is assumed).
Think of it this way;
>suppose your 318 makes 200ftlbs at 2000rpm, the probable current stall speed. That would be 76hp., jus saying
> now suppose your 318 makes 220ftlbs at 2800. That would be 117hp.
> from 76 to 117, is an increase , coming out of the TC of 54%; and there is nothing short of supercharging your 318, that can touch that.
> now suppose your current gears are the typical 2.76s. And at 200 ftlbs at the crank, going thru the 2.45 first gear, that would be 1352 ftlbs to the road. But with 3.23s and 220 ftlbs, that would be 1741#, an increase of 29% ; again only supercharging can touch that.
A2800TC really woke up my smogger-teen, and 4.30s sealed the deal. Later, I got me an A998 with the 2.74 low gear in it, and with 3.55s, that took off like 3.97s
With 27" tires;
2.76s will cruise at 65=~2230rpm at zero-slip. your tach could say more or less depending on the load
3.23s will cruise at 65=~2610@ zero-slip.
But here's the deal;
with 2.76s and a 2800TC and traveling at 65mph; as you slam the gas pedal down,but before the downshift, the rpm will rev up to 2800 OR MORE, whereas the 2000 stall may slip 8%, so 2400.
Passing gear at 55mph;
with 2.76s. the Rs will jump to about 2740 plus slip, so say 3014@10% slip.
with 3.23s, the Rs will jump to about 3210 plus slip, so say 3530@10% slip.
Where would you rather be?
I'm sure Rumble is about to put his gums in gear, so here's the final deal;
I'm not assuming anything, and I'm not leaving anything out.
I'm merely giving examples, for your perusal, so you can wrap your head around how this all works.
Furthermore, you need to understand something else;
Suppose you currently had 3.23s and a 2000stall. And using the above 318 example that made 200ftlbs at 2000rpm; to the road, this is 1583 ftlbs in first gear.
Now suppose you installed a 2800TC and swapped out the 3.23s for 2.76s. Again in first gear but at 220 ftlbs crank, this is 1488 ftlbs . So even tho you gave up 15% gear multiplication, you only gave up 6% torque delivery.
Now swap out the A904 for the A999, and get the 2.74 low gear (compared to the 2.45), and the latter example becomes 1664ftlbs, a GAIN of 5% over the A904/2000stall. Of course your hi-way cruise rpm changes from say 2610@0% slip, to 2230 in loc-up mode, yes with the 2800TC.
If this is a dedicated city car, with an A904; I would be tempted to gear it for peak-power at say 55mph in Second gear, which, with an A904 would take 4.56s. and thus 55= about 5000@10% slip, in Second gear.
With an A999 this would take 4.30s hence why I ran them.
Be advised tho;
once the Rs have climbed to past the stall-rpm, any performance gain after that, has to come from Torque-multiplication, or motor.
With the A904, 2.76s, and a 2000 stall, this comes at about 22mph.
with the A999, 3.23s, and a 2800, this comes at about 23mph
At this point, with the engine unchanged, the 3.23s will out-accelerate the 2.76s....... until you increase the cranking pressure, or the cubic inches, or the valve-timing events..
Finally; suppose you installed better flowing heads and a bigger cam to let them work, but did not increase the compression ratio, nor made any changes to the chassis or the rest of the powertrain; if you did this, your low rpm power is almost guaranteed to suffer, as will your low-SPEED performance.
But say the net result of the smaller combustion chambers and later-closing intake valve angle, sets your engine up for the same before and after cranking cylinder pressure, so then, your low rpm power is likely to be the same as it was in the earlier iteration, namely; below about 3000 to perhaps as high as 3500, there will be NO perceptible performance gain. Ok hang on a sec;
Without tirespin; in first gear with an A904 and 2.76s, 3000rpm will get you 36mph, and 3500 is 42mph. (Yes Rumble, with 27" tires, and at 10% slip@WOT.)
So I ask you; where should you spend your money?
Well, where do you want the performance increase?
And that takes us back to the top of the page.
Happy HotRodding
for improved off-idle to low-speed/low-rpm, performance,
the best bang for the buck, is a higher-stall TC , and/or higher rear gears, (the 4bbl and free-flowing exhaust is assumed).
Think of it this way;
>suppose your 318 makes 200ftlbs at 2000rpm, the probable current stall speed. That would be 76hp., jus saying
> now suppose your 318 makes 220ftlbs at 2800. That would be 117hp.
> from 76 to 117, is an increase , coming out of the TC of 54%; and there is nothing short of supercharging your 318, that can touch that.
> now suppose your current gears are the typical 2.76s. And at 200 ftlbs at the crank, going thru the 2.45 first gear, that would be 1352 ftlbs to the road. But with 3.23s and 220 ftlbs, that would be 1741#, an increase of 29% ; again only supercharging can touch that.
A2800TC really woke up my smogger-teen, and 4.30s sealed the deal. Later, I got me an A998 with the 2.74 low gear in it, and with 3.55s, that took off like 3.97s
With 27" tires;
2.76s will cruise at 65=~2230rpm at zero-slip. your tach could say more or less depending on the load
3.23s will cruise at 65=~2610@ zero-slip.
But here's the deal;
with 2.76s and a 2800TC and traveling at 65mph; as you slam the gas pedal down,but before the downshift, the rpm will rev up to 2800 OR MORE, whereas the 2000 stall may slip 8%, so 2400.
Passing gear at 55mph;
with 2.76s. the Rs will jump to about 2740 plus slip, so say 3014@10% slip.
with 3.23s, the Rs will jump to about 3210 plus slip, so say 3530@10% slip.
Where would you rather be?
I'm sure Rumble is about to put his gums in gear, so here's the final deal;
I'm not assuming anything, and I'm not leaving anything out.
I'm merely giving examples, for your perusal, so you can wrap your head around how this all works.
Furthermore, you need to understand something else;
Suppose you currently had 3.23s and a 2000stall. And using the above 318 example that made 200ftlbs at 2000rpm; to the road, this is 1583 ftlbs in first gear.
Now suppose you installed a 2800TC and swapped out the 3.23s for 2.76s. Again in first gear but at 220 ftlbs crank, this is 1488 ftlbs . So even tho you gave up 15% gear multiplication, you only gave up 6% torque delivery.
Now swap out the A904 for the A999, and get the 2.74 low gear (compared to the 2.45), and the latter example becomes 1664ftlbs, a GAIN of 5% over the A904/2000stall. Of course your hi-way cruise rpm changes from say 2610@0% slip, to 2230 in loc-up mode, yes with the 2800TC.
If this is a dedicated city car, with an A904; I would be tempted to gear it for peak-power at say 55mph in Second gear, which, with an A904 would take 4.56s. and thus 55= about 5000@10% slip, in Second gear.
With an A999 this would take 4.30s hence why I ran them.
Be advised tho;
once the Rs have climbed to past the stall-rpm, any performance gain after that, has to come from Torque-multiplication, or motor.
With the A904, 2.76s, and a 2000 stall, this comes at about 22mph.
with the A999, 3.23s, and a 2800, this comes at about 23mph
At this point, with the engine unchanged, the 3.23s will out-accelerate the 2.76s....... until you increase the cranking pressure, or the cubic inches, or the valve-timing events..
Finally; suppose you installed better flowing heads and a bigger cam to let them work, but did not increase the compression ratio, nor made any changes to the chassis or the rest of the powertrain; if you did this, your low rpm power is almost guaranteed to suffer, as will your low-SPEED performance.
But say the net result of the smaller combustion chambers and later-closing intake valve angle, sets your engine up for the same before and after cranking cylinder pressure, so then, your low rpm power is likely to be the same as it was in the earlier iteration, namely; below about 3000 to perhaps as high as 3500, there will be NO perceptible performance gain. Ok hang on a sec;
Without tirespin; in first gear with an A904 and 2.76s, 3000rpm will get you 36mph, and 3500 is 42mph. (Yes Rumble, with 27" tires, and at 10% slip@WOT.)
So I ask you; where should you spend your money?
Well, where do you want the performance increase?
And that takes us back to the top of the page.
Happy HotRodding
cookietruck
Well-Known Member
for a cruiser, see if you can score a set of black friday discounted Speedmaster heads.
Jpar seems to be fine with them. if you need a little reassurance do like he did and pay $65 or whatever it was to have a machine shop chekc them out
Jpar seems to be fine with them. if you need a little reassurance do like he did and pay $65 or whatever it was to have a machine shop chekc them out
Funny you should mention that. My bare Promaxx CNC 185 shockers were sitting on my porch when I pulled up in the driveway.
They were awesomely cheap at the low, low price of around $1800, and that's with the $100 discount code SUMMER at my absolutely most favoritist super-duper awesome non-clowns at JEGS.
Ignore the sarcasm, JEGS was my only option for the 63cc chambers bare heads. I'll post up some pics in the appropriate thread later.
Funny you should mention JEGS. They just screwed me on a holley throttle body elbow. Oh yeah it's in stock, NOT!
Yeah, I loathe JEGS. I have been watching prices climbing and supply chains stumbling about like they stepped on a Lego in the dark. So, I held my nose and ordered from them. They are my absolute last choice.
I have a late 91 magnum and a 94 one, both have the passages I would assume that 91 thru 94 blocks have the passages
Seems Trickflow is competitive compared to Promaxx if you have to buy rockers anyway. No need for geometry correction too.
Agreed.
I already had my rockers so went with the Promaxx heads. Plus I want to try conical springs and the tool steel retainers so after all is said and done, it'll pretty much be a wash on cost. If I really really wanted to be competitive with the trick flows, I would lose 30 to 40 pounds and lay off the pasta.
My Promaxx heads needed very little geometry correction. Seems they fixed it somewhat as did Trickflow. Probably not as well as Trickflow though.
CarWash
Well-Known Member
We have a set of Edelbrock “bolt-on out-of-the-box” heads on our 410 small block. On the box it says “bolt these right on”, but the factory assembly was terrible, the valve job was sketchy and we had to redo the entire valve job for our own safety before we put them on the engine.
Buyer beware, it doesn’t matter what country they’re made in, it has to do with the quality of the people who are putting it together in the final assembly.
Buyer beware, it doesn’t matter what country they’re made in, it has to do with the quality of the people who are putting it together in the final assembly.
Dan the man
Well-Known Member
This is true and also the reason why I probably will buy bare cylinder heads.
You can and should do that but set some limits, no need to go overboard. There are many members that over thought, over built, and ended up disappointed with the drivability and mileage. I am talking about a radical combination that only works with your foot to the floor and tires screaming and impossible to run 70 down the interstate to a out if town car cruise while getting 5 mpg with $5 gas.
Mopartech68
New Member
Lots of option converting LA heads to Magnums, Mancini has 1.5 Rockers that oil the valve train through the push rods and
PRW Industries
Manufacturer's Part Number:
3231811, and I have heard Comp Cams has a set and Speed master ( Just never heard good things about speed master rocker arms )
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