Swapping out a TH350 for a 700R4

[frank_a]

I want to go to a 4 speed OD tranny when I pull the hot rod apart. Looks to me from research that an '87 to '89 2wd 700R4 tranny would be best, as it is before the electronic stuff, and after the earlier weaker versions.

My TH350 has the short tailshaft and is 27 11/16 long. The 700R4 is 30 3/4 long, meaning I would also have to have my driveshaft shortened by 3-1/16. Also, the tranny mount is back 20 3/8 on the TH350 and 22 1/2 on the 700R4, so that would also have to be moved back 2-1/8. I don't see these things as big hangups, but was wondering if anyone can verify what I have found, especially on this dimension stuff.

I was real lucky with my TH350. Bought it out of a junkyard for $150, changed the fluid and filter, pounded the living you-know-what out of it for years, never had a problem. Figure I'm running maybe 350 hp, maybe 400 ft lbs of torque, but those are just guesses.

So what do I do? Get a junkyard 700R4, maybe go to a pick and pull, see if I can find one? Then I need a high stall torque converter right? (Local junkyard quoted me 400 bucks for a tranny) Of course, who knows? It could work fine forever like my TH350 did, or die the 1st day. Or dig deep and buy a rebuilt street rod tranny for a grand or so that comes with a torque converter? Then I want to make sure it has that lockup stuff, but that's just something integral to the torque convertor right? Do I need to do some kind of wiring to use one of these babies?

Questions, questions...

Frank

[Lee in KC]

I'm going to be following this effort very closely, Frank, as you are doing exactly what I've been thinkng about doing. Every time I go cruising in the T I kick myself for not going with an overdrive tranny from day one. I had even spec'ed a crossmember location for the 700R4 when I ordered my frame from Spirit, but then changed to a TH350 when I saw what a 500+ hp/tq 700R4 was going to cost.

[frank_a]

Looks like some pick and pulls around here (couple hours away) sell any tranny for around 100 bucks with a $25 core charge. That sure is more like the kinda budget I have Lee, but this is gonna be done over time, so I gotta give this some thought. I can always do the chassis work just based off specs I guess. But yeah, between a bit more length to the frame and no excessive engine noise at highway speed (let alone mpg stuff), this would be a good thing!

Gotta pull the T out of storage this weekend and give it a general cleaning. No questions I got to do something with it - the chassis is getting pretty rusty. I'm wondering whether even to worry about tires right now, just go ahead, pull it apart, do some work on the chassis and get it powder coated. I got $850 in the bank right now, and figure I can put on average maybe $300/month into it. Over the next year that would add up and allow me to get some other stuff I've been wanting.

No fear though Lee, anything I do will be well documented. My major Christmas gift this last year was a nice Canon DSLR, extra lenses and a tripod. I've always loved taking pictures, and really got into digital photography with Canon point & shoots. I can't wait to get started!

Frank

[Kevin Seward]

Looks like some pick and pulls around here (couple hours away) sell any tranny for around 100 bucks with a $25 core charge. That sure is more like the kinda budget I have Lee, but this is gonna be done over time, so I gotta give this some thought. I can always do the chassis work just based off specs I guess. But yeah, between a bit more length to the frame and no excessive engine noise at highway speed (let alone mpg stuff), this would be a good thing!

Gotta pull the T out of storage this weekend and give it a general cleaning. No questions I got to do something with it - the chassis is getting pretty rusty. I'm wondering whether even to worry about tires right now, just go ahead, pull it apart, do some work on the chassis and get it powder coated. I got $850 in the bank right now, and figure I can put on average maybe $300/month into it. Over the next year that would add up and allow me to get some other stuff I've been wanting.

No fear though Lee, anything I do will be well documented. My major Christmas gift this last year was a nice Canon DSLR, extra lenses and a tripod. I've always loved taking pictures, and really got into digital photography with Canon point & shoots. I can't wait to get started!

Frank

Hey Frank and Lee,

I have sometimes thought about going to an overdrive as well. My deal is I am starting with a 400 that has been bullet proof and don't want to give that up either. On occasion I still like to play so I will be watching this along with you Lee.

No pressure Frank

Later

Hitec

[frank_a]

Yeah, but the 700R4 has a 3.06 1st gear Kevin! 1st gear in the TH400 is 2.48, the TH350 2.52. More oomph off the line, less rpm on the highway, better mileage.

Frank

[John Eplen]

Hey Frank,

Great to see you back on the BBS & getting your T back in service. I've been wanting to reply to your frame coating post for several days now & saw this post about going to an overdrive tranny. Thought I'd mention what my brother did on his '34 Sedan Delivery (I posted pics when we were upholstering it) concerning an overdrive trans.

He originally put a turbo 350 in and, after doing some checking around, exchanged it for a 200-4R. That allows you to use your present drive shaft (no cutting necessary) & cross member w/a slight weld on 5" extension plate to bolt the tranny to. I cut him a piece of 1/4" plate from some of my stock & he had Melvin's shop weld it in & drill it since they were doing the work in their shop which is across the street from his warehouse. If you have a Lokar shifter, they have a conversion kit ($95.00) for the overdrive trans. However, the 200-R4 is not friendly to high HP/torque. So, if you get a stock unit you might check your local transmission rebuilders to see if they can beef it up for your T before you buy it. I just talked to Toolman last week who mentioned that he had put the same tranny in his T. He got his from an after market company in California.

My brother got his 200-R4 from Transmission Depot in Hudson, FL. He paid $995.00 + shipping & it's a bullet proof rebuild for over 1,000 HP. He said that I could give you or anyone else (Lee/Kevin) his phone number and he would be happy to give a complete run down on what procedures to do. He also can give you the name of the guy to contact at Transmission Depot. His has been performing great w/1,700 rpm's at 70 mph. If anyone would like to talk to him concerning this matter email me & I'll return his telephone number. t_pilot@verizon.net

About the coating on your frame. I've run on to some Dupli-Color Engine Enamel (it's Ceramic-good to 500o) Gloss Black DE 1613. I used this on my frame where I had to repair another crack in my frame, discovered when I got back from Weelstang's annual Sept. meet in Artesia, NM. My T has been on the lift since late Sept. because I'm also trying to put in an overdrive trans, the only difference is mine is a stick shift (Tremec TKO 500). But, when I discovered the crack I knew I had to fix it first.

This Dupli-Color give a good high gloss. I didn't do multiple coats, I just wanted to get the metal protected. You can make this into a powder coat type finish by using a heat gun to go over the sprayed area. I have a Dayton unit that almost throws out a flame so it must be kept off the surface quite a ways. I'll post a pic that shows my air cleaner which I was able to bake in the oven at 200o's for about an hour or so. With the heat gun you would want to try to reach the surface temp. to 200o's; but keep the gun moving, never staying in one place to avoid blistering the paint. They have this paint in several different colors. It might be a good paint to consider if you refresh your Jag IRS. I think yours was white? I haven't noticed this paint in white, but that doesn't mean that Dupli-Color doesn't make a white. I get these paints at my NAPA store.

Here's 2 pics of the black frame repair. This first on looks like h*ll, but I'll have to wait for a future tear down to make it pretty. This was all overhead & liked to have killed me trying to stay steady. Finally ended up sitting on a stool & putting a 2x4 in to lean on w/no room for my helment/or leather one either.

[frank_a]

Hey John!

Good to hear from you!

Yes, I have a lot of work to do on this old hot rod. Interesting info on the 200-4R. Thing is, if I'm pulling the whole hot rod apart, it makes little difference which way I go for OD. Changing the tranny mount is nowhere near as complicated as extending the chassis! Having said that, I will take a look at the 200. That price your brother paid is about what I'm seeing built 700R4's going for, but I think the stall converters are extra.

That Dupli-Color Engine Enamel sounds interesting, never thought about heating it like that John. I'll have to take a look at that stuff. Seems to me I have used that on my t bucket headers and on the powerhead of the old merc I run on the old speedboat.

Just so ya know, I also plan on installing doors (yep, plural) and removing the bench seat for some old buckets I pulled out of an IHC Scout years ago. The buckets need to be completely rebuilt, but they will fit.

I'll keep ya posted. Thanks!

Frank

[Bob Lemke]

Frank,

I've been there, done that. The first engine/trans was a 355 circle track race engine and a Muncie M21 4 speed. After switching to a 383 sbc built for torque as low in the rpm band as possible, I swapped trans for the TKO-600 5 speed with 0.64 OD. On this engine, the top gear was perfect because the torque peak of 516 ft/lb was at a very low 2800 rpm. I have 31" rear tires and a Jag IRS 3.54. 70 mph highway cruising was at 1700 rpm and twice I broke 30 mpg. And since the engine was built for torque at the low end, the valve timing events made for a very quiet little rumble of a exhaust note. The 355 was a high rpm engine with street manners no better than a gang banger and a loud raspy exhaust bark. It would have hated the 0.64 OD, and that is why I'm giving input to your upcoming trans swap. If you have a mild build, then you will love the tall OD. If you have a performance build, you might want to stay one to one on the top gear ratio. I have just put in a Scott Shafiroff 427 sbc that doesn't like anything below 2000 rpm, and is only tolerant of 2000, so my 0.64 is just too tall for any freeway cruising below 75 mph. There are plenty of "speed in gears" calculators on the Internet that will let you plug in tire diameter, rear end ratios, trans ratios, and crank out your speed in gears. With this 427, I would have gone with the 0.83 OD TKO-600 box, but like I said, bought it for the torque grunting 383.

To give you an idea of how well the 383 dealt with low rpms under load, this picture shows me pulling a grade at 1025 rpm in top gear.


I have posted more of my driving impressions here......
http://nationaltbucketalliance.com/bb/v ... &start=330

Good luck on the trans update Frank, I'll be following this thread also along with Lee.

[Bob Lemke]

See if this posts without getting scrambled.

RPM First Gear Second Gear Third Gear Fourth Gear Fifth Gear
200 1.8 2.8 4.1 5.2 8.1
400 3.6 5.5 8.1 10.4 16.3
600 5.4 8.3 12.2 15.6 24.4
800 7.3 11.0 16.3 20.8 32.6
1000 9.1 13.8 20.4 26.1 40.7
1200 10.9 16.5 24.4 31.3 48.8
1400 12.7 19.3 28.5 36.5 57.0
1600 14.5 22.1 32.6 41.7 65.1
1800 16.3 24.8 36.6 46.9 73.3
2000 18.2 27.6 40.7 52.1 81.4
2200 20.0 30.3 44.8 57.3 89.6
2400 21.8 33.1 48.8 62.5 97.7
2600 23.6 35.8 52.9 67.7 105.8
2800 25.4 38.6 57.0 72.9 114.0
3000 27.2 41.4 61.1 78.2 122.1
3200 29.0 44.1 65.1 83.4 130.3
3400 30.9 46.9 69.2 88.6 138.4
3600 32.7 49.6 73.3 93.8 146.5
3800 34.5 52.4 77.3 99.0 154.7
4000 36.3 55.1 81.4 104.2 162.8
4200 38.1 57.9 85.5 109.4 171.0
4400 39.9 60.7 89.6 114.6 179.1
4600 41.8 63.4 93.6 119.8 187.3
4800 43.6 66.2 97.7 125.1 195.4
5000 45.4 68.9 101.8 130.3 203.5
5200 47.2 71.7 105.8 135.5 211.7
5400 49.0 74.4 109.9 140.7 219.8
5600 50.8 77.2 114.0 145.9 228.0
5800 52.6 79.9 118.0 151.1 236.1
6000 54.5 82.7 122.1 156.3 244.2
6200 56.3 85.5 126.2 161.5 252.4

And yes, 2800 rpm in top gear gives some speed.



OK, it does get scrambled, so the speeds do not line up under each gear, but here is the calculator for you to use.
http://www.precisionsite.com/auto-x/tools/

[frank_a]

Okay, more specifics.

First of all, I am not opposed to a 200R4, it's just gonna be pretty much what I find first. I do appreciate the suggestion and info. No driveshaft work necessary, just moving the tranny mount. Let's see what I come up with. Part of the problem is I may not have the tranny before I do whatever I'm gonna do to the frame, so I may just have to weld on mounts and then get the tranny when I can afford it. We'll see.

That Dupli-Color Engine Enamel idea is very interesting. I'm not sure I would feel confident doing that on my frame, but maybe other smaller stuff, like the jag IRS. Then again, I have a powder coat set up and shop oven, so again, gotta think this stuff through.

Did you do that orange air cleaner with Dupli-Color Engine Enamel?

Take care and have a great weekend!

Frank

Hey Frank,

Great to see you back on the BBS & getting your T back in service. I've been wanting to reply to your frame coating post for several days now & saw this post about going to an overdrive tranny. Thought I'd mention what my brother did on his '34 Sedan Delivery (I posted pics when we were upholstering it) concerning an overdrive trans.

He originally put a turbo 350 in and, after doing some checking around, exchanged it for a 200-4R. That allows you to use your present drive shaft (no cutting necessary) & cross member w/a slight weld on 5" extension plate to bolt the tranny to. I cut him a piece of 1/4" plate from some of my stock & he had Melvin's shop weld it in & drill it since they were doing the work in their shop which is across the street from his warehouse. If you have a Lokar shifter, they have a conversion kit ($95.00) for the overdrive trans. However, the 200-R4 is not friendly to high HP/torque. So, if you get a stock unit you might check your local transmission rebuilders to see if they can beef it up for your T before you buy it. I just talked to Toolman last week who mentioned that he had put the same tranny in his T. He got his from an after market company in California.

My brother got his 200-R4 from Transmission Depot in Hudson, FL. He paid $995.00 + shipping & it's a bullet proof rebuild for over 1,000 HP. He said that I could give you or anyone else (Lee/Kevin) his phone number and he would be happy to give a complete run down on what procedures to do. He also can give you the name of the guy to contact at Transmission Depot. His has been performing great w/1,700 rpm's at 70 mph. If anyone would like to talk to him concerning this matter email me & I'll return his telephone number. t_pilot@verizon.net

About the coating on your frame. I've run on to some Dupli-Color Engine Enamel (it's Ceramic-good to 500o) Gloss Black DE 1613. I used this on my frame where I had to repair another crack in my frame, discovered when I got back from Weelstang's annual Sept. meet in Artesia, NM. My T has been on the lift since late Sept. because I'm also trying to put in an overdrive trans, the only difference is mine is a stick shift (Tremec TKO 500). But, when I discovered the crack I knew I had to fix it first.

This Dupli-Color give a good high gloss. I didn't do multiple coats, I just wanted to get the metal protected. You can make this into a powder coat type finish by using a heat gun to go over the sprayed area. I have a Dayton unit that almost throws out a flame so it must be kept off the surface quite a ways. I'll post a pic that shows my air cleaner which I was able to bake in the oven at 200o's for about an hour or so. With the heat gun you would want to try to reach the surface temp. to 200o's; but keep the gun moving, never staying in one place to avoid blistering the paint. They have this paint in several different colors. It might be a good paint to consider if you refresh your Jag IRS. I think yours was white? I haven't noticed this paint in white, but that doesn't mean that Dupli-Color doesn't make a white. I get these paints at my NAPA store.

Here's 2 pics of the black frame repair. This first on looks like h*ll, but I'll have to wait for a future tear down to make it pretty. This was all overhead & liked to have killed me trying to stay steady. Finally ended up sitting on a stool & putting a 2x4 in to lean on w/no room for my helment/or leather one either.