Slight performance build on a 518

C

cmann250

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My 260k+ mile 727 is leaving a lot to be desired lately in my '89. I want to do a slight performance build and upgrade to a 518 in the near future.

Here's the details: The truck is stock, yet turned up (274hp/503tq). I do not intend to change my air or fuel in the foreseeable future. I tow a gooseneck more often that the average guy carrying hay, antique tractors, pick-up trucks, etc. I think I'll try my hand at drag racing this summer and I may or may not get hooked, pun intended. It's a 2wd.

What should I look to do to this 518? I already have a Suncoast converter purchased, but I'm not 100% sure it will suit me because it's supposed to be stock stall. I assume a shift kit of some sort is in order. I seriously doubt I need a billet input at a whopping 274 hp.

I want to build this right the first time. Pointers, tips, advice, etc. is welcome.
 
Talk to BC847. One of the few guys still running non lock-up and had documented quite well what it takes to make them hold
 
oldestof11 said:
Talk to BC847. One of the few guys still running non lock-up and had documented quite well what it takes to make them hold
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True, but 450+ hp leaving the line in 4wd at 20-some psi is different than normal driving unloaded 75% of the time, towing 20% of the time, and actually running the truck hard 5% of the time. I've read and payed attention to what he has to say and learned a thing or two, but our transmissions live different lives.

I'm in that middle ground that no one really talks about.
 
A rebuild with a shift kit and good tc should do what you want. I would get a tighter tc then stock though. I would make sure you have 4 forward and 4 direct clutches, not sure what the early 518s came with for direct.
 
What I am doing now
ATS kit rated 600hp/1000ft
Had to buy low/rev band separate
Spec rite converter
Transgo HD shift kit
Also did the billet servos

Waiting on a couple parts and then it's time! I am hoping to eventually put 400hp to the tire on fuel and still work it.
 
Good convertor, 4.2 apply lever, heavy band strut and anchor, full rebuild, hd/tow shift Kit. Enjoy. Are you planning to regear? If you go lower stall and tow it's going to be tuff to get moving. I went 150 under on mine with 3.55s, seems good.
 
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Knoberman said:
Are you planning to regear? If you go lower stall and tow it's going to be tuff to get moving. I went 150 under on mine with 3.55s, seems good.
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Well I have 3.07s now. I kind of like them with O/D (I had a 47RH previously, long story), but I would not be opposed to move to 3.55s. I think it's one of those things that I am going to have to try out in order to find what suits me. Maybe the "high" 2200 rpm stall is needed with 3.07s?
 
Grudgeguy said:
Anyone running the 5.0 (hemi) kickdown lever? I was gonna try it
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Sutter1stgen is. Last I heard, it was giving him troubles.

After talking to a few people and doing some reading, my converter is a lower stall unit, so it is good to go.

What's the general consensus on a deeper pan?

As of now, the plan appears to be the converter, TFOD shift kit (seems to have a lot of high reviews), better cooler behind the grille, and a good rebuild/confirmation of hardware on the inside. I'll probably upgrade some of the band hardware just for durability's sake.
 
You'd be smart if you called TransGo about that TFOD kit as with you explaining to them what you plan to do, you'll be surprised that they may steer you toward a better suited kit for your intended application. The TFOD kit may very well end up with left over parts when you're done.

Do yourself a favor and concentrate more on the bushings and thrust washers in the trans (through out). Renew them if they present as anything other than pristine. Don't run an apply-lever any more than the 4.2 (do not run the 5).
 
Don't run an apply-lever any more than the 4.2 (do not run the 5).

This right here. I've got it adjusted where I like it, but the 2-3 shift isn't as fast as I'd like. Yet it's still better than stock. I may pull it out one of these days.
 
BC847 said:
You'd be smart if you called TransGo about that TFOD kit as with you explaining to them what you plan to do, you'll be surprised that they may steer you toward a better suited kit for your intended application. The TFOD kit may very well end up with left over parts when you're done.

Do yourself a favor and concentrate more on the bushings and thrust washers in the trans (through out).
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I've heard about the extra parts for the 47RH. Supposedly the Jr. kit is non-lock-up specific, but I'll call them before I get too excited. It's on the list of things to do before I make a final decision.

Unless I can document a rebuild within 10k miles, it's getting opened up and inspected. BTDT with a 47RH. And yes, I have very competent back up.
 
Bc while we're talking about the 5:1 lever I have a question. In the instructional video I watched for some help with my rebuild tge builder said 2.5 turns out for a 3.8 lever and lower, and 2.25 turns out for the higher ratio levers. This makes sense to me because the higher the ratio the higher the leverage, but at the cost of overall band clamping travel. Tighter tolerances would be needed to have the band apply all of the way.
Now when the 2-3 shift happens both forward and direct clutches are applied, to creat 1:1, along with the release of the second gear band. I know this needs to happen well timed to get a crisp shift.
So far I've backed the second gear band out 2.75 turns, this has helped with the timing quite a bit. I've wondered if a guy could back the band off a little more??? Just to make the shift that much better, say like 3 turns.
Or am I thinking of this all wrong, and asking for a slipped second gear band??? I'm half tempted to drop my trans and swap out the apply levers. I'm worried that if I back it off too much that the lever is going to reach full stroke, and the band will have NOT reach full clamp. Even though it's a super duper high ratio lever.

Thanks.
 
The increased clamping force afforded by the lever comes at the expense of a longer servo stroke. (The fulcrum has been moved).

I don't know that altering the initial linkage slack adjustment is doing you any good. Same thing with altering gear shift timing via introducing/removing slack from the servo linkages. I smell burnt clutch material. :aiwebs_029:

Perhaps those with more experience will chime in.
 
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Thanks. I think I'll just pull it out and swap it out for a more diesel friendly apply lever.
I can see it working with a gasser engine, for the fact that you never really shift below 1800rpm. But with a diesel, part throttle, residential neighborhood shifts are lower than that. I just serviced the trans, well here we go again.
Thanks for the reply.
 
Well BC I finally called suncoast. I talked with Ernie. His recommendation was to install a stiffer front servo return spring. He said it would help with the 5:1 lever release, and said it should help with the shift timing. He was a real nice guy and really knew his stuff. I also like the fact that they didn't bad mouth the company I ordered from, and on top if that they helped me out over the phone, even though I hadn't spent a dime with them. Now that's customer service.
 
I like my 1-2 shift, but my 2-3 shift is too quick, I think I had a different servo spring but not sure, how would one go about changing that? 3-4 is really good, if I could get 2-3 right I'd be happy.
 
My 727 held 514rwhp with just a converter, shift kit, and clutches. I've heard of a few people ripping the splines out of the planetary at about 550-600rwhp, but the stock stuff is pretty stout. If I was you, I would upgrade to the steel planets, always regretted not doing that.
 
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