1986 442 project (street and strip)

[bfurches]

I would be stuffing a th200 under the car with its 2.74 first and let it eat...

If a TH-2004R can handle the boost from a Grand National's V6 it surely can handle any power out of a 307, boosted or not.

I've had a built TH-2004R in the past that was behind my 455 for years. Daily drove that car and never had a problem. Ended up destroying the converter but was lucky that it just turned the fluid pitch black but that trans just kept going. Flushed it out and installed the trans behind my brother's 403 and it's still been going strong.

Sorry for the confusion, I was not bashing the 2004r....the th200 transmission is an anemic 3 spd produced in the 70's I was refering to. It has a nice low gear from a performance standpoint, and the transmission itself is fairly compact and light, but they don't hold up very well without some really expensive parts.
__________________________________________________________________

In regards to the other post, there are several good points made about having the od in a street application. I will have to look into what the hard parts cost, and maybe I will reconsider, but im still up in the air.

Cost is a big factor here...I have a lot of the th350 stuff already, and parts like convertors are relativley cheaper when compared to the 2004r stuff....but regardless I will take the sugestions into consideration and at the very least look at the cost of the hard parts i would need.

th350 weighs in at 10lbs less then the 2004r, but the 200 has a better first gear. I believe the 2004r robs a little less power than the th350, but the th350 is a little more stout...
Thanks guys.

 

[FE3X CLONE]

Sorry for the confusion, I was not bashing the 2004r....the th200 transmission is an anemic 3 spd produced in the 70's I was refering to. It has a nice low gear from a performance standpoint, and the transmission itself is fairly compact and light, but they don't hold up very well without some really expensive parts.

The TH-2004R has the same first gear ratio as the TH-200 so that was my confusion. A lot of guys will interchange the two and think that because the TH-2004R was originaly based on the TH-200 that it is still just as weak.

 

[bfurches]

Sorry for the confusion, I was not bashing the 2004r....the th200 transmission is an anemic 3 spd produced in the 70's I was refering to. It has a nice low gear from a performance standpoint, and the transmission itself is fairly compact and light, but they don't hold up very well without some really expensive parts.

The TH-2004R has the same first gear ratio as the TH-200 so that was my confusion. A lot of guys will interchange the two and think that because the TH-2004R was originaly based on the TH-200 that it is still just as weak.

I was reading that there were a few different gear selections for the 2004r, but after looking through some of my parts books, I could only find the one gear set (2.74) listed....this is the same gear set in my transmission correct?

Also, does anyone know of an adjustable vacuum swicth I could wire into a relay to control convertor lock-up if I were to stay with the 2004r? I cant bring myself to spend stupid money on a tci or the likes controller....

 

[FE3X CLONE]

I was reading that there were a few different gear selections for the 2004r, but after looking through some of my parts books, I could only find the one gear set (2.74) listed....this is the same gear set in my transmission correct?

Correct. The gear ratios for the TH-2004R are:

1st: 2.74
2nd: 1.57
3rd: 1.00
4th: 0.67

Also, does anyone know of an adjustable vacuum swicth I could wire into a relay to control convertor lock-up if I were to stay with the 2004r? I cant bring myself to spend stupid money on a tci or the likes controller....

The TCI setup is a total waste of money anyway. Been there, done that and it worked like crap. We installed the B&M lockuip kit on my brother's TCI TH-2004R (which is a junk trans BTW) and it works much nicer but still not "factory" smooth.

Take a look at this thread. Some good information about using the vacuum switches from mid-80's pickups in there:

http://72.22.90.30/phpBB2/viewtopic.php?t=76346

 

[dogsht]

fwiw I had two factory 200-4R lock-up converters re-built one out of my GN to a 3,000 stall and one out of my 442 to a 2,800 stall. Furnace brazed bla bla both times it was $300.

 

[bfurches]

fwiw I had two factory 200-4R lock-up converters re-built one out of my GN to a 3,000 stall and one out of my 442 to a 2,800 stall. Furnace brazed bla bla both times it was $300.

Not a bad price at all...

I'm not going to lie....that 200-4r with a 28" tall tire and 3.42 (MAYBE even 3.73) would put me right where I want to be on the big end...

Thanks guys for bringing some of that stuff to my attention!
__________________________________________

A little side note:

I didn't make it over to Radioshack today to pick up the parts I need for my Mallory box, but it's all good. I am going to try like hell to run over there tomorrow. I did find a mint dash locally to replace mine that is practically destroyed. Same color and everything complete with everything right down to a stock cutlass cluster for 75.00, so I couldn't pass that up.

I am hoping that this weekend I can get the following stuff squared away:
1) complete removing all the air tubes from the heads and plug the holes
2) completely remove the CCC harness and computer from the car and clean up the engine bay
3) hopefully have a Mallory ignition box to install in place of the old CCC computer
4) repair my console and install my B&M hammer shifter
5) map out placement of the turbo and hot-side parts

...that's a lot of stuff for one weekend lol (may not sound like a lot, but I am working overtime saturday...so needless to say, this should be a tight fit lol)

 

[dogsht]

Define the big end in mph & rpm. What do you think HP will be? A stock vin Y 307 is done by 4300 rpms. A vin 9 that you should have is done by 4,800. I will copy a post from another thread and you can use it to determine your ideal gearing.



I will show you how to do it for yourself. http://www.wallaceracing.com then click automotive calculators. You will need two of them:

HP from 1/4 MPH and weight

and MPH - Gear ratio

HP from 1/4 MPH & weight calculator tells you ideal gearing (whatever that is) and what mph your 500 flywheel HP can push your 3,800 pounds to. answer 118 MPH. Don't worry about the ET blank just fill in MPH and weight blanks changing the MPH until it matches your 500 flywheel HP.

Then use the MPH - Gear calculatorto find what gear will put you at or closest to your maximum HP rpm ie 5,600.

Result 500HP & 3.90 gears on 28" tires (275/60/15 or 275/40/18 drag radials) can get your 3,800 pounds to 119 mph in the 1/4 or just past your 5,600 maximum HP rpm and would be for practical purposes ideal 1/4 mile gearing.

On top of that you can also put 2,200 rpms into the MPH - Gear calculator and .67 into the trans gear ratio box (for the 200-4R) to see that you would be traveling at 70 mph just puring along comfortably getting proably maximum cruising MPG (side benefit) out of a cam that is big enough to make 500HP from your 455. No taxing your cooling system and no spinning the snot out of your big block investment AND bad arse on the strip.

Now you just need traction (we will leave that for another conversation) and a good stall converter to match your cam etc. You probably have something around 230@50 duration or better to make that HP which would leave near maximum torque at around 3,000 rpms. For $300 bucks I had one of my factory 200-4R "D5" lock-up converters rebuilt & upgraded furnace braised etc to 3,000 stall. Some of the great things about it being a working lockup converter is that under normal part throttle driving conditions it drives as nice as a stock converter ie smooth, better mileage, and no excessive heat taxing your cooling system. All because its not slipping. Its only at heavy throttle when you bang out of the hole and realize with a big grin that you have a high stall converter.

On top of that the 200-4R is lighter has less rotating mass to spin up and is more efficient than old three speeds or most other overdrive transmissions. Its only challenge is that it has to be pro built and if you are putting it behind a 500+ foot pound of torque big block you need a billet forward drum. It doesnt work well in a heavy vehicle or towing situation either partly because of the small pan & limited fluid capacity. Sorry for the 200-4R commercial.

See why I say the overdrive transmission is the single best upgrade to a real driven hot street car. Three speeds are for drag/race cars or local only stop light to stop light cars or I can't afford better cars othewise they should be left in the 70s as they are that far out of date. Hope that helps and that I didn't bore you with too much info.





Naturally that had things in it specific to the other post but you can follow the directions to match your project and variables such as different gears or tire height.

 

[bfurches]

Define the big end in mph & rpm. What do you think HP will be? A stock vin Y 307 is done by 4300 rpms. A vin 9 that you should have is done by 4,800.

By big end I am referring to the mph I would be crossing the traps at....

In an ideal setup, if I can get the car where i want it to be on boost, I would need to trap about 110-115

Take my car with a 3.73 rear gear, 28" tall tire, and going through the traps at 5,200 rpm, I would have a mph of 116 (obviously these are all "in a perfect world" numbers)...

Take the same numbers, factor in crossing the line at 5,000 rpm...and I should still trap 111? Both mph would put me exactly where I want to be (assuming everything else works), Im not killing the rpm on the big end, and letting the turbo do its job where the 307 likes to make its power (down low)...

Now this would be nice because it leaves room for improvement. Lets just say I get lucky, the motor responds well, holds together and likes it if I feed some q16 and up the boost....and lets say now I can cross the traps at 120+ (again, this is just an example)....well now I can step down the a 3.42, keep the motor in the same operating range and essentailly cross the traps at the same rpm as with the 3.73. Peak effieceny of the application.

(obviously the numbers listed above are crossing the traps in third which is 1:1)

I really feel this would make the perfect setup. The only thing nicer would be if my idea will work for the modified first gear to a 3.054

Lets say I could make 350ft-lbs x 2.74 first gear x 3.73 rear = 3577 ft lbs applied on the launch to the rear tire...
take the same setup, 350ft-lbs x 3.054 first gear x 3.73 rear = 3,987 ft lbs applied ....thats over 400 ft lbs more on the launch....

This motor will never be a monster, so it needs to be optimized everywhere else. Every little trick will count.

 

[dogsht]

Turbo or not I doubt you get that kind of power out of a stock 307. But if you could get 405 flywheel HP and it weighed 3,800 with you turbo fuel etc the calculator says it could push you to a 110mph in a quartermile. The other calculator tells me it would take a 3.73 with a 28" tire & a little slippage 5000 rpm to go 110mph in the quarter. So if peake HP is at say 4,800 rpms this would be an ideal gearing to power to weight match if all the input numbers are correct.

fwiw more torque multiplication out of first gear is only good to the limit of traction. On top of that a torque type setup such as a 307 especially a turbo 307 assuming the right converter would only likely put it out of its pull to soon. Some would say it runs out of breath too soon before pulling the next gear. You can have too much of what would seem like a good thing.

The ultra low first gear of a 700-4R back in the day helped get a relatively heavy pick up truck moving with a relatively weak 305. But if I tried to use that behind the 509ci Caddy motor in my 442 it would just blister the tires. If it did hook it might not have pulled as well as a taller first gear before hitting second. But again it was a great thing to help a weak 305 get a heavy truck rolling.

 

[bfurches]

Turbo or not I doubt you get that kind of power out of a stock 307.

Time will tell 🙂
I am trying like hell to get it ready so I can at least make a few shake down passes this year...