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Discussion Starter · #1 ·
I bought a 6.2 mated to a 4L80E this last weekend. My intentions for it is to swap the tranny for a 4 speed, something more friendly to speed and put in a Model A rat rod. I guess my biggest question is what should I be doing to this 6.2 to make it fast? For trans I was thinking a Saginaw or Muncie. As long as it is a 4 bolt main will it work with this motor? For rear end I was thinking Ford 9" with either 4:11 gears or 3:73. Does it sound like I am on the right track for this build? I am new to diesels and would appreciate any help.
Thanks
 

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Different, thats for sure. If you want top end speed, your gears will be too low for a diesel and in all actuallity, your car will be substantially lighter than the trucks that engine was intended for. So, I would think even if its for quarter mile performance, you'd still be able to get away with something in the 3.08 to 3.40 range. I'm pretty sure the 6.2 will adequately relocate the gears outside the case of a saginaw, so I would avoid that. As far as a 4spd car tranny goes, I would roll with a super T10 or an M-22 rockcrusher. The 9 in should hold. I think everyoune here would agree, turbo it, bump the injection pump timing a titch, and bump the fuel adjustment in the pump (provided some or all of these things have not been already done). Larger than stock exhaust system will also help, I don't know exactly what size to go with as I'm still trying to find out the ideal size. Main thing to remember with any diesel, you can't crank out the rpms like with a gasser. They will die a horrible explosive death. My guess may be a little high, but I think 4500 or 5000 is about max for a 6.2. Hope this help at least a little. Good Luck.
 

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bbbadboy said:
My guess may be a little high, but I think 4500 or 5000 is about max for a 6.2. Hope this help at least a little. Good Luck.
LOL Yeah a little high. 6.2s are governed around 3600rpm. Since they are governed they won't fuel at higher rpms than that.


As for the trans a 4l80e has either a .70 or .73 overdrive so I don't know how much faster you want to go :shrug:

A ford 9" will be more than enough, gear it to match your speed goals to the rpm and trans you want to run. Best mileage is between 1600-1800 if your curious, and the 6.2 reacts well to low gears.

Click Here for a fair guide for 6.2 performance. I've been dying to throw some studs in a 6.2 and see how they work. they are really cheap for a diesel. Add some significant timing and through some fuel or maybe injectables into it, and hope it doesn't blow up. With the engine in a "body" like that it should be fairly easy to swap stuff out, do be afraid to experiment
 

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WOW, this works out great! Between your hot rod, and my making dual k20s laugh with an inaccurate guess, I got exactly the info I've been seeking. Hopefully, you did to. I'll be sure to guess a little high again when I need info (LMAO). Good Luck with your hotrod, it'll be unique. I'd love to hear how it turns out (I like a unique ride).
 

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The super T-10 and the M-22 have straight cut gears which makes the teeth of the gears thicker, therefore stronger. The downside: They are loud and much harder to find, therefore more expensive when you do. These 2 trannys were put primarily in GM's muscle of the muscle cars in the 60's and first couple of yrs of the 70's. I know there are upgraded reman M-22 available. Do a google search for "muncie transmissions" or "m-22" you'll find a few outlets for them. For the price they are asking (around $1500 if memory serves), it'd be worthwhile to save the headache in finding and rebuilding one. Goodluck:Thumbup:
 

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Discussion Starter · #7 ·
I am trying to build this car on the cheap so a $1500 trans is out of the question. Would there be a tranny I could find at a junkyard that would work? This rod is going to be my daily in the spring and summer so it will not be beat on like a drag car.
 

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You can get a saginaw 4 spd out of pretty much any gm car that had the option. Best bet would be just about any year camaro. They are pretty reasonably priced. You should be able to get a used one (depending on your area) for no more than $200-$300. Don't bang the gears or sidestep the clutch with this one though. They'll handle the horsepower just fine, its the torque that kills em.
 

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What speed are you looking to turn with it, and what size tires will it fit, that will dictate a lot. If you're only looking for the 110mph range, you could get away with a GM 10bolt out of a camero in the rear, with 3.08's or higher gears, and a sm465. That is a 4speed with a really low first gear, which would do well off the line, and a 1:1 4th. With the 3.08s or higher, you should be able to turn nearly 110-120mph. I believe the camero came with a 2.69:1 rearend ratio in some of them or something like that. Also that stuff can be picked up dirt cheap. Maybe $150 for a decent trans, and $200 for the rear end. I'm helping my cousin install That trans behind his 6.2 in a blazer next weekend.
Sean
 

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Discussion Starter · #10 ·
The 110-120 mph range is really the fastest im looking to go, so it sounds like I should be looking for an sm465. What would one of those come out of? Camaro?
 

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The sm465 came in early 70's to the 90's in 1/2, 3/4, and 1-ton trucks. I believe it was preceded by the similar sm420 with an even lower 7.05:1 first gear :wow
 

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A little late on this post but....a gm 6.2 diesel into a Model A Ford just seems so wrong on so many levels to me, but that's just my distaste for mixing brands.
 

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hi, i am into 6.2's alot and had a thread on heare at one time about my turbo 6.2 build but it was lost. i used a turbo off of a 96' 6.5 and plumbed it into my 83' 6.2 , turned the injection pump up 1/4 turn , straight piped it with 3" pipe and used an afe intake off a duramax, i probably make over 215hp "guestimate" it will light the duallys up with the sm465 trans on 1st and 2nd gear no problem :):). my dump has 4.10 gears and tops out at 78mph so if your going to run 110mph id use alot taller gears. ill post some turbo setup pics on here soon for you
 

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I would run a nv 3500 5spd out of 88+ pickup I have run over 400hp through mine for 3 years and it just does not miss a beat, they are a little bully shifting but the long life and low price more than makes up for it.
 

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A little late on this post but....a gm 6.2 diesel into a Model A Ford just seems so wrong on so many levels to me, but that's just my distaste for mixing brands.
yea it would atleast make more sence to use a

:thumbsup GM 400 409 427 454 or Ford 351 390 427 428 429 460:thumbsup . . .
:thumbsup some thing stand outish cool n known for power :thumbsup . . .

Building a HotRod from a 6.2L diesel seems a bit :eek: !

Mike
 
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