What type of torque converter would you guys recommend for Road Racing/Autocross use? I would love to someday swap a new Tremec TKX into my Skylark, but it's just not financially feasible right now. So I'm going to continue with my plan of replacing the original TH350 with a 2004R. I already have the trans that I bought about 5 years ago, it's a BQ code from a T-Type. I have no idea what the condition is but was told it worked by the seller so I was just going to do some basic cleanup, maybe a shift kit and a pan with a drain. Maybe an upgraded front pump? Definitely going to run the biggest cooler I can find, and probably some sort of scattershield. It came with a torque convertor, but again I have no idea what it is or if it's even a lockup unit (which I want). I've heard mixed things when searching the web, it's pretty hard to find people running autocross or road course with an automatic. My concern is that if I use a convertor with a high stall speed, it would make precise throttle adjustments feel muddy. The goal here is to have the car respond well and have smooth power delivery when say rolling on the throttle exiting a turn into the straightaway. I'd want smooth downshifting as well. Would a full manual VB be a good choice too? Most of them do away with engine braking . . .
Not answering your question, but wondering out loud, what is the total cost you think it will take with the mods you want to do to the 2004R including converter and any incidentals? Then the difference needed to go with the TKX conversion. And ask, if you do the 2004R and after all of it is said and done and you are unhappy, would it have made sense to sell what you have and trim off more of the total to go with the TKX?
Let's see, here's my breakdown of costs for both options from my looong planning list: TH-2004R -Better Torque Converter ($350 from CKP) -Scattershield? ($?) -Killduff Shifter with Cable/Bracket (no console) $565 -B&M 70244 Lockup Kit - $253 -TV cable kit - $60-250 -Pressure testing gauges ($80?) -Cooler and plumbing ($250?) -Shift kit or Manual VB? ($130 Shift Kit, $450? VB) -Upgrade front pump? ($300) -Upgrade servo? ($130) -Better pan ($250?) -Upgraded oil pickup ($100) Total with Shift Kit and cheaper TV kit: $2468 Total minus oil pickup, servo, front pump upgrades: $1938 --------------------- Tremec TKX -Trans - $2,700 -Flywheel - $325 -Clutch Kit $500 -Pilot bushing install? Need to machine crank? ($?) -TPP Conversion Auto to Manual kit - $300 -Hurst Shifter handle/knob - $120 -Custom Center console? ($?) Total - $3,945 So looks like the TKX is roughly double the cost if I decide to cheap out a little more on the auto. I'm sure there are options on both of these that I'm forgetting. Or for cheap I could throw the trans and convertor in as is, maybe spend a few hundred for the TV and Lockup kit, use the column shifter for now. I'd rather do it a little nicer than that either way!
I would keep the th-350 until you can buy the TKX. Keep in mind that a good lockup converter that will handle BBB torque is about $700-$900, the single disk lockup in a $350 converter won’t hold up. I use a triple disk lockup converter from Hughes that’s rated to lockup at 600+ Hp. Also I wouldn’t spend a penny on the 200 unless I was doing a full rebuild. I wouldn’t want a manual valve body personally for autocross. A 2500 stall and leaving the trans auto would be my advice if you go that way. A high end converter won’t be soggy, a low cost one will be.
$2000 difference. How much cash can you reasonably expect to get for everything you could sell from what you have on hand and won't need if you put three pedals in the car? If you are anywhere near half again (up $3000) to the cost of the Tremec, it's a no brainer to go with the pedal car and don't look back. But, easy for me to spend your time and money. I'm coming from my closet full of t-shirts.
Thanks for the advice y'all! I guess it does make more sense to save for the TKX and keep the TH350 or at least just drop the 2004R in without any mods and see if it works. I could probably sell it for I dunno, $500 or so maybe? Perhaps I'll hold onto it for now and sell it when I get closer to needing the trans ready. Either way I'm going to have to fab a cross member for my trans if choice. I boxed my frame and now there's no way to bolt in the stock cross member! The big "if" here is, I don't know if my crankshaft is machined for a pilot bushing, and unfortunately I can't fit calipers in there while it's on the engine stand to measure. If I need to drop the crank to go manual, I might as well wait until I rebuild the engine!
I'd sell that 200. I'd never swap one of those transmissions again. Let the next guy deal with all the issues or spend big money and fix all the issues...
If you have a hoist, snuggle it up to the engine stand and lift the engine, take the plate off and verify the crank then put it back. Heck, you could probably do it an about three eggnogs!
I do have a hoist, it's rather buried in my other garage crap at the moment, but I'm going to need it soon anyways to drop the engine. I'll measure for it before the engine goes back in!
Also think about the time and $ adding the 200 plus the parts you want to upgrade. Then end up with a slipping trans that’s worth nothing and you still need to spend all the $ to do the 6 speed that you really want. a good 200 trans could get you $500 most likely but if it’s slipping it’s $100ish
Makes sense! I guess TH350 it is for now then, I don't want to let the manual swap delay getting the car back together. So does that mean I should keep the stock torque convertor in the TH350? I'll probably at least throw a TransGo kit in it.
I would think for road racing you would want a stock tight converter since you are on off the throttle all the time. Would cook a higher stall one and feel mushy. And forget about lockup...it's not going to have time to lockup. But that's just my take on it......
Agree 100%.. you should be keeping the car in first or second gear at high rpm anyway. A loose converter is not what you want.
It all depends on what camshaft and compression ratio the engine runs. If the engine doesn't wake up till 2500 then use a similar stall. Stock engine, stock converter is fine.
This will eventually be going behind the twin turbo 350 (6-8 psi, intercooled, shooting for 400ish to the wheels). Likely I'll be running the TH350 or 2004R behind the NA version first, then Turbo the engine, then manual swap after the engine is all ironed out. All part of my 30 year plan
Sounds great! There is a lockup 200 converter in the parts for sale section on here. I think it was a 2400 stall, I could be mistaken. Just run a toggle switch and keep it unlocked for the auto cross. You will likely end up wanting some sort of progressive boost controller to reduce tire spin, but that’s easy to add after just start low on boost. Get ready to get addicted to the boost, the feeling gets your blood flowing instantly.
