alum edelbrock heads

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Hey rumble;
I tried that OD4spd.with 3.55s. It does not play well with 110LDA, and the 232*cam. The %rpm drops between gears is just too wide.
The ratios are 3.09-1.67-1.00-73.. The %drops are 54-60-73. Around town, typically I like to shift at 2800. The engine seems happy at 2800. Well, at 54%, it drops into 2nd at 1500/20mph. The 232* cam doesnt have a bunch of tq there, so acceleration from there is a bit LAZY, but ok, I can keep up with traffic. Going into third, from 2800/38mph in 2nd is a drop to 60%, so we are in at 1680rpm/38mph.But I had to claw my way up to 60 [email protected] then the shift into O/D drops the Rs to 1955.
I didnt like that.
So I swapped in some 4.30s.That brought the cruise rpm to 2400ish.Thats ok.
But now comes the crap.Again using a comfortable 2800 shift point, the drop-ins are 17/31/and 52; always climbing out of the basement.
This was all well and not-so-good, but the starter gear of 4.3 x 3.09 = 13.29 was just ridiculous. Thats the equivalent of running the oem 2.66low tranny with a 5.00 chunk.First gear was useless. And 2nd was too far away.
This very wide ratio would work really well with a stock type engine, that has a low rpm operating range, and a wide,powerful,torque band.
So then I bolted my GV up behind that, and used it as a gear splitter.And bolted in some 3.91s..That actually worked pretty well.I had 7, yes, SEVEN useable gears, ending in a double O/D. The ratios were; 12.08-9.42-6.53-5.09-3.91-3.05-2.22.....But I soon found the constant splitting, tedious.
So then I called up Passon Performance, And he had a nice 3.09/direct4th set. Well he talked me into one of his new aluminum cases and side-covers,too. I like that guy. So now I have a 5speed with splitting capabilities. The ratios are(with 3.55s); 10.97-6.82-4.97-3.55-2.77...Perfect for a streeter.But it gets better. I actually normaly split 3-4, so the ratios that I use are; 10.97-6.82-4.97-3.88-2.77 .
But it gets even better! In the 1/8 with 3.91s, I split 1-2, so the ratios are; 12.08-9.42-7.51-5.86.With just one stick change.This puts me at around 6800.
And in the qt(havent run it yet), I would run 4.3s.. The ratios would be; 13.29-10.36-8.26-6.02-4.7With just two stick changes.That would get me 6800@116mph, if I had enough power!
Aint math fun.
To tell the truth tho, for street,Id rather have a regular 5spd, with 4 gears close, and a deep o/d. Mo money.
 
Wow! I was thinking auto A-500 for the Magnum.
Stock '00 - 5.9 with Edel. RPM intake and 650 Thunder, Hooker Super Comp headers @ 1-3/4 into 2-1/2 exhaust. 3.55's on 26 inch wheels.

The Super Comps are old (but in excellent shape) and purchased below $300. They fit to nicely to remove. I'll never do the one size fits all ever again!

I'm still waiting to do a cam. I want to keep it small.
Oh, crappy 2500 Summit stall converter for now in a 727.
 
nm9
You are a funny guy.
I believe its on account of my tuning skills.HaH! I can be funny too.
No , I believe I dodged the bullet. Back in 97, when the body was in the bodyshop, I had 2 years to do the research. Like said nobody was talking Dcrs.
I just went with my gut and back engineering known magazine combos. Arrived at 9/1 Dcr as safe with al heads. I arbitrarily bumped it to 9.2,for my elevation(750), expecting ramifications. By the time the engine and body met,everybody was worried about the new oxygenated gas.Well I could hardly wait for it to get here. I knew that the alchohol burned cleaner, and was more detonation resistant. About that same time, or a little earlier,they switched the octane ratings.So by the time the car was registered as roadworthy, it was september/99. I set the timing to 36*, and much to my surprise,had built a monster.
I drove it til Oct 10th and parked it for the winter.Tuning began the following spring(2000).And lasted for 4 years.


rumble
I read the .59, but didnt clue in.
The Mopar auto-trannys suffer from large rpm drops too,especially the low gear ones. But a higher stall TC is a good work-round. Its tougher when the clutch dont slip.
If I was going auto-o/d, Id go GM. They make it so easy now.
 
AJ/FormS said:
No , I believe I dodged the bullet. Back in 97, when the body was in the bodyshop, I had 2 years to do the research. Like said nobody was talking Dcrs.
I just went with my gut and back engineering known magazine combos. Arrived at 9/1 Dcr as safe with al heads.
Click to expand...
OK, many thanks. Back-engineering the other combos gives a rational basis for the number; IMO, that's a good method of working it out. I'll be doing a bit more research on that. I like to use non-ethanol gas in my old car to avoid issues when sitting for a few months so I may not benefit from the ethanol aspect.

Now you need a 2 speed rear axle to add to your present double OD!
 
AJ/FormS said:
rumble
I read the .59, but didnt clue in.
The Mopar auto-trannys suffer from large rpm drops too,especially the low gear ones. But a higher stall TC is a good work-round. Its tougher when the clutch dont slip.
If I was going auto-o/d, Id go GM. They make it so easy now.
Click to expand...
Problem is the $$$. You'd have gear vendors levels in a trans that isn't really any better than a built 500/518 that'd be a few hundred and has cheap cores. The 500/518 4th is .69 and then the usual 2.7/1.54/1 and 2.45/1.45/1 gears respectively.

Even the app changes what you'd want to have in it immensely. I'd have not one problem with 4.10s or 4.30s and a 904 in a Cherokee with 28s or 29s but on the otherhand 3.55s in a car without OD and tires in the 25-27" range is something I hate and in a truck- I'd like to be more conservative than that as well if it's gonna see the street much.
 
Rumble
Do you already have the set-up installed? Now I get it! I think I get it.
Did I mention I loved that Hughes 223*cam?lol

nm9
Yeah, I contemplated the Winters set-up.But... My pockets aint that deep!
 
Well then,I have an idea for you.I havent researched it in the a/t arena, but; If you find an O/D tranny that would allow you to use its O/D as a splitter, and chose a set of tranny ratios that worked with the splitting, then you could effectively build a 6 speed trans with very tight ratio splits, and very small rpm-drops during shifts. This would allow you to go to a tighter LDA, and a smaller camshaft,and a lower stall TC,and/or rear-gears to arrive at the same average hp delivery per unit of distance travelled.And this would translate to less fuel useage at part throttle cruising.
What this all boils down to, Im sure you have already figured out. But for those that might not have grasped this; the same mph at the big end, for a smaller cam, or even a smaller engine, than with a conventional 3 spd auto, and/or a more economical-to-operate engine.Translation; more streetable, but still ear-to-ear-grin fast.
Now, the Mopar o/d trannys are out. The .69 o/d ratio is much to deep for effective splitting. A .78 or so would be much closer to what would be needed. So lets back engineer that.
Six speeds is too many for the Qt. With a small street-type engine 5 would be sufficient. A fun Streeter would be a small-cam 360. That engine would do well with a 4 gear Qt, and a 3 gear 1/8th. So lets start with 4 for the 1/4.
Lets say that small cam 360 has the potential to go 106, and the hp peaks about 5400.But that engine has a well chosen support works so the hp falls very slowly after 5600, and is still doing very well at 6000.
So we are gonna want to cross the line around 6000.Lets also chose a 27 inch tire. Doing the math, this gives us a on-the-line ratio of 4.56(convenient,I know). But this will be in 2nd-o/d. so the rear-end ratio x the 2nd gear ratio, will be 4.56/.78= 5.846.
So the tranny ratio times the rear ratio will be 5.846.So we need to find a combination that satisfies this while still giving us a nice final drive.
Well it just so happens that, 5.846/1.45(typical Mopar 2nd) yields a 4.03 gear, which we will round down to 3.91. And also conveniently,3.91 x .78=3.128cruising gear. So we are in good shape so far, with 3.91s out back and a 1.45 second gear. Lets do 1st.
To get to 1st, we first need to get to 1st-o/d,so 1.45/.78=1st-o/d =1.86; and 1st is 1.86/.78 =2.38,None too-far from 2.45, the standard Mopar 1st gear.
--So it looks like the standard Mopar ratios would work pretty good with the .78 gear-splitting, and 3.91s. Lets work it out; the ratios are 2.45-1.91-1.45-1.13-1.00-.78, and the spits are;.78-.76-.78-.88-.78. (Well look at that! if you wanna go really fast, you could gear it(4.56s)to go 5 gears in the qt, and take advantage of that last .88split.)
With this set-up, the starter gear is 3.91x 2.45=9.58. But the TC will multiply that some, perhaps 5%, so lets say 10.06. This is an excellent street starter gear. And if you swap in some 4.56s for the track;the starter gear works out to about 11.7.
And the final-drive of 3.91x.78=3.05, puts you at [email protected] too bad.
--To be sure, there are other transmissions with wider ratios that might work out better with a different splitting ratio.I just chose all the parameters to work with stuff that we are all familiar with.
BTW, the .78 splitting ratio puts the rpm drop from 6000 to 4680, thats a powerband of 1320rpm, centered at 5340rpm.Thats a nice street cam. A 223*@050,fast-rate, high-lift might get you there, with a tight ringseal and good flowing heads.
Personally, Id be looking at the 700R4 and its family.
Okay then, lunch time.

mopar
sorry to hijack your thread.
 
AJ, you so have to shorten your extremely informative posts.

I'll be honest and say the idea was rejected at;

Well then,I have an idea for you.I havent researched it in the a/t arena, but; If you find a tranny that would allow you to use the O/D as a splitter, and chose a set of tranny ratios that worked with the splitting, then you could effectively build a 6 speed trans with very tight ratio splits, and very small rpm-drops
Click to expand...

Adding a GV/OD is stone stupid crazy expensive. It's not even a thought for an option.
Thanks for the response.
 
No-No. I wasnt suggesting adding a GearVendor. I was suggesting a search for an auto trans with a more compatible overdrive ratio, that could be used for splitting,than the Mopar .69-o/d. Something closer to .78.This would be all in the same box, like a 700R4. Im not familiar with other brands, so the search would be yours.

Post 58 edited.
 
Well guys my build got outta hand in a hurry. I got the eddies. $1000 loaded and never been ran. Tomorrow the motor goes to maching. 30 over with speed pro 116cp's. Crank is getting reground. Im getting a 750dp holley on monday. Geeze!!!!!
 
MoparOrNokar said:
Well guys my build got outta hand in a hurry. I got the eddies. $1000 loaded and never been ran. Tomorrow the motor goes to maching. 30 over with speed pro 116cp's. Crank is getting reground. Im getting a 750dp holley on monday. Geeze!!!!!
Click to expand...
Seems pretty normal to me...LOL. The heads sound like a good deal. Any reason for the 750 DP and not something like a 650 vaccum carb? Have oyu worked out a static CR with the machine shop?
 
nm9stheham said:
Seems pretty normal to me...LOL. The heads sound like a good deal. Any reason for the 750 DP and not something like a 650 vaccum carb? Have oyu worked out a static CR with the machine shop?
Click to expand...

Its not normal on a 2500 budget lol. My nieghbors best friend use to be a great machine and builder in my area a while ago. He had a stroke 10 years ago and lost the left side of his body so he had to stop. He still has the machine shop. Idk why the 750. Im just listening to everything he tells me. Like i said he was a go to guy for roundy round guys and drag guys for a long time.
 
A 750 DP is a. Excellent carb for the task at hand and should be used NO doubt considering the only thing about your combo I don't know about is the cam and actual compression ratio & displacement though the piston choice gives me a great clue.

You run that 750 & listen to that guy.
 
Well if youre jumping in with both feet, I hope those pistons are coming to the top.

Cause if they do, 1 to 1.1hp/cid is pretty easy, on 87E10, with .039quench.

But if they dont come up, you may be buying Hi-Test only.
 
0w
Well. With those heads, .030 o/s pistons down .012, 5cc eyebrows, and a .039x4.18 gasket, the Scr comes to 10.44; and the quench comes to .051.You pretty much have to run the 1008 gasket to survive.The .028 gasket would be better for quench at .040, but its hard to say how long it would survive.
Now for a cam. To get the Dcr down for 87gas, the ICA needs to be at about 60*atdc,for 8.6. We know that works. A slightly smaller cam at 53* gets a Dcr of 9.0,for 89 to 91 gas. A larger cam of 66* gets a Dcr of 8.23.
These Dcrs are all for sealevel. At 1000ft, you can subtract .2ish from the Dcrs, so the 53* cam becomes 8.8Dcr, and now 87/91 gas-able.But the 66*cam then puts the Dcr down around 8.0,still do-able.
Get your builder to verify the numbers, after the pistons are in, and;
Happy cam hunting!
 
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