700R4 Conversion Guys...Lessons Learned...Pros and Cons Please
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Race Director
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From: San Jose CA
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Rick Church)
Dropping 1000 rpms on the freeway... well, the peace of mind is definitely worth the cash, in my opinion! Plus, freeway mileage jumps, and I gained just a bit of city gas mileage too.
-Steve
-Steve
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Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Rick Church)
Rick,
I've done the conversion. So far for me the only down side was the cost, and if I ever blow it up the rebuild cost...unless I can convince Larry to drive over from Orlando and do it for free beer :D
I added 3.55's before I did the tranny swap and didn't like the gears on the highway. After the tranny swap I drove up to the museum from Florida and still got over 20mpg, and still had good top end speed. Around town 4th gear is pretty useless, since I try to stick close to the speed limit and avoid drawing the attention of the local police, I don't like paying the speeding tax.
Lessons learned, well do your homework which is what you are doing now. Unless you can swap the tranny yourself, have welding skills and can redo the crossmember you're probably better off getting the BTO one or one from an 82. I bought the pressure guage and speedo gears as well. The speedo gears are an easy job, the pressure set up takes a little more time and you'll need help. That's about all I can really tell you on the technical side, there's a bunch of people here who know trannies much better than I do. Overall, it's not a hard conversion at all.
I've done the conversion. So far for me the only down side was the cost, and if I ever blow it up the rebuild cost...unless I can convince Larry to drive over from Orlando and do it for free beer :D
I added 3.55's before I did the tranny swap and didn't like the gears on the highway. After the tranny swap I drove up to the museum from Florida and still got over 20mpg, and still had good top end speed. Around town 4th gear is pretty useless, since I try to stick close to the speed limit and avoid drawing the attention of the local police, I don't like paying the speeding tax.
Lessons learned, well do your homework which is what you are doing now. Unless you can swap the tranny yourself, have welding skills and can redo the crossmember you're probably better off getting the BTO one or one from an 82. I bought the pressure guage and speedo gears as well. The speedo gears are an easy job, the pressure set up takes a little more time and you'll need help. That's about all I can really tell you on the technical side, there's a bunch of people here who know trannies much better than I do. Overall, it's not a hard conversion at all.
Safety Car
Joined: Mar 2000
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From: Northeast South Dakota
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (C3 Shark Tank)
I am considering this as well. Does anybody have the TCC kit from bow tie overdrives? If so how does it work? Is it a toggle switch kind of thing??? How much modification needs to be done to the crossmember? How far off are the tranny cooler lines? (I used to run a tube bending factory so I can make some, just curious how far off they are) Is the connection for the shifter cable the same, and how about the connections of the kickdown cable on the carb?
Hows that for a slug of questions??????? :D
-Justin
Hows that for a slug of questions??????? :D
-Justin
Melting Slicks
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From: Reno NV
St. Jude Donor '08
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Rick Church)
im also thinking of doing this, just because I would really like an over drive. But will it bolt up to a 454?
thanks a bunch
Dave
thanks a bunch
Dave
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From: Severna Park Md
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Rick Church)
Consider the 200R4 as an option too. I did it with mine and after more than a year and several thousand miles of hard drivin I would use the 200R again. nice trans..close ratio 1st to 2nd. I just had the pan off for a govenor change to taylor the shift points and the tranny is still spotless inside. The govenor mod has raised the WOT shift points to right where I want them. I now have shift kit on the way to make it bark like a dawg. Im lovin this tranny more all the time.
Cant think of any drawbacks of moving up to a 4spd o/d tranny. Except for maybe the initial expense.
I got my 200R from BTO. I have been getting my tranny tuning advice from Bruce Tolle @ Performance Transmissions In Sacramento Ca. He is know to be one of 3 top 200R guys in the country. http://www.2004rPerformanceCenter.com
Cant think of any drawbacks of moving up to a 4spd o/d tranny. Except for maybe the initial expense.
I got my 200R from BTO. I have been getting my tranny tuning advice from Bruce Tolle @ Performance Transmissions In Sacramento Ca. He is know to be one of 3 top 200R guys in the country. http://www.2004rPerformanceCenter.com
Le Mans Master
Joined: Sep 2000
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From: Orlando Floriduh
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Rick Church)
Here's some food for thought. C-4's use these 700R4's so the C4 board can give you a lot of info. The 700 R4 is not without problems however.. The are can be hard on 3-4 clutches if they are driven in OD around town. This creates a "lugged" condition that really kills these transmissions, especially if you are putting any serious power to it. They are difficult to rebuild.... As a side note here... I had a 92 with a 700R4. C4's have milage computers that will tell you the milage you are getting at the moment. At 75 mph there was LESS than 1/2 mpg difference between 3rd and 4th(OD). The low milage gain really surprised me. I did like the low gear ratios of 1st and 2nd. I would not trade a TH400 for a 700R4.
Team Owner
Joined: Jul 1999
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From: Orange Park Florida
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (silvervetteman)
Years ago I had a Trans-Go kit in a 400 tranny, it shifted pretty good, and lasted decades and 350k miles, still slammed 3rd gear pretty good....
well NOW with a 700r4 and a Superior kit...I"m disappointed....
I allready went through a 3/4 clutch pack, and a 1/3? band it's silly how short a life those have....
I"m thinking a Trans go kit will help immensley, and new clutches again, and maybe another band also...it's running 'ok' for now....
I feel that blocking or shimming the accumulator valve springs and relaxing the throttle valve may be the way to go....lower pressures, but remove accumulators...the old Trans go system....
GENE
well NOW with a 700r4 and a Superior kit...I"m disappointed....
I allready went through a 3/4 clutch pack, and a 1/3? band it's silly how short a life those have....
I"m thinking a Trans go kit will help immensley, and new clutches again, and maybe another band also...it's running 'ok' for now....
I feel that blocking or shimming the accumulator valve springs and relaxing the throttle valve may be the way to go....lower pressures, but remove accumulators...the old Trans go system....
GENE
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From: Quincy IL
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (mrvette)
I didn't find a large jump in mileage, but that's probably because i can't keep my foot out of this thing. i think my mileage went up because i had the motor rebuilt the same time i converted to 700r4. my typical mileage is about 13 mpg with my high being around 15 mpg. i've got the original 3:55 rear gears. before the rebuild i got about 10-12 mpg, bad carb,tired engine. my primary reason for the 700r4 was i didn't want to spend the $$$ on the engine and then go out & turn almost 4000rpm @ 70mph with the th350 tranny again. i used bowtie od for the tranny and adapter plate mount, got the shift kit from them, also a Bosch relay that's tied into my brake lights. i used a manifold vaccuum switch from TCI,ordered thru Jeg's, it provides lock-up in 4th gear and when i hit the brakes(Bosch relay), lock-up is off. no toggle switches on the dash or console, nothing to mess with,except drive the car. my wife sometimes drives the vette and i didn't want her to have to remember to flip a switch on and off. it wasn't that bad of a conversion on a 79. i had never done anything like this before and did it in my garage along with the motor removal and re-installation.
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From: Reno Nevada
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Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Rick Church)
I did the conversion to 700R4 back when it was the hot rodders rage of the mid to late 80's. I used the 82 vette dipstick and TV cable. I also had to eliminate my cruise control and went with the 82 straight through cable. I modified my existing crossmember to run 3 inch pipes straight back from the header collectors.
You really need 3.90 or so gears. My original 3.55's were too tall so I jumped to 4.11. With lower gears like mine your not aware of the supposed big gear jumps because it closes them up.
IMO - your better off with a 5-6 speed.
[Modified by gkull, 9:07 AM 7/26/2002]
You really need 3.90 or so gears. My original 3.55's were too tall so I jumped to 4.11. With lower gears like mine your not aware of the supposed big gear jumps because it closes them up.
IMO - your better off with a 5-6 speed.
[Modified by gkull, 9:07 AM 7/26/2002]
Le Mans Master
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From: Chattanooga TN
St. Jude Donor '08-'09
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (C3 Shark Tank)
As for the rebuild cost; the guy who rebuilt my TH350 will rebuild about anything (i.e. TH350, TH400, 700r4, 4L60E, etc.) for $150 + convertor (if you want or need one). So I wouldn't let that stop me. I've heard that the low 1st gear is great, but I've also heard that the RPM drop between 1st and 2nd isn't great for drag racing. I have the 4L60E in my S-10 and I love it. I had a 700r4 that I ALMOST put in my '79, but I sold it to finance other stuff. I regret not doing it when I had the chance.
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From: Northeast South Dakota
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (e3pres)
How does the 200R4 fit in the car? I just acquired 2 of these yesterday. They will need a rebuild, but then they'll be ready to go.
Le Mans Master
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From: Coming home from Luckenbach Texas
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Dalannex)
Hey! I could use one of those... :D Wanna sell one?
It's basically is a "remove & replace" operation, but you need some accessories (and a lockup torque converter). Bowtie Overdrives can provide all the stuff (and info) you need!
It's basically is a "remove & replace" operation, but you need some accessories (and a lockup torque converter). Bowtie Overdrives can provide all the stuff (and info) you need!
Safety Car
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From: Northeast South Dakota
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (page62)
So the crossmember can stay like it is, and the driveshaft? That would leave me with a TV cable to address, and I see in Jegs there are a number of different kits to work out the lockup of the converter. Does the converter for a 200R4 bolt right up to my flexplate, or do I need to order a special converter?
Team Owner
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Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Dalannex)
So the crossmember can stay like it is, and the driveshaft? That would leave me with a TV cable to address, and I see in Jegs there are a number of different kits to work out the lockup of the converter. Does the converter for a 200R4 bolt right up to my flexplate, or do I need to order a special converter?
Drive shaft has to be shortened.
You will need the TV cable setup, and a way to lock up the TC.
I personally would buy the entire kit from BowTie overdrives. I had mine done by a local shop, and they did a really good job. But, to do it at home, go with the kit.
Le Mans Master
Joined: Mar 2002
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From: Coming home from Luckenbach Texas
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Dalannex)
No crossmember, driveshaft fits right up. Cooling lines should be okay, too!
But you need a lockup converter, TV cable (in some cases), lower shroud, shifter, dipstick and a few other gewgaws. Bowtie will put together a kit for you -- just tell 'em what you got! They answer emails in great detail (like the one I got -- 33 kbytes!)
That's okay about the tranny -- we have junkyards FULL of old GM stuff (and no rust)!
But you need a lockup converter, TV cable (in some cases), lower shroud, shifter, dipstick and a few other gewgaws. Bowtie will put together a kit for you -- just tell 'em what you got! They answer emails in great detail (like the one I got -- 33 kbytes!)
That's okay about the tranny -- we have junkyards FULL of old GM stuff (and no rust)!
Melting Slicks
Joined: Mar 2002
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From: The cure for the blues is eight cylinders roaring
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (page62)
check out this thread has some good info on the 200-4r.
Sorry cant make this thread work.http://forums.corvetteforum.com/zerothread?id=305132
[Modified by Wightnite, 4:29 PM 7/26/2002] :mad
[Modified by Wightnite, 4:36 PM 7/26/2002]
Sorry cant make this thread work.http://forums.corvetteforum.com/zerothread?id=305132
[Modified by Wightnite, 4:29 PM 7/26/2002] :mad
[Modified by Wightnite, 4:36 PM 7/26/2002]
Safety Car
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From: Severna Park Md
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Wightnite)
The 200R is the same length as the th400, both in overall length and in bellhousing to mount length. If you are removing a th400 there is no need for custom crossmember. The original will wotk in the original location. Also the driveshaft will not require cutting. It will work as is provided you replace the fron yoke with the proper type.
If you are removing a th350 the story is different. I have no expierence with that swap so cannot offer any difinitive insight.
I will say that thew 200R is a kick A trans when set up right. it works great for me with my 3.90 gears. Its through 1st and 2nd very quickly. Especially 2nd, 2nd is there and gone in no time. commin outa 1st@5500rpm and droppin into 2nd around 3500rpm....waaaaaa..sweet spot..you get the picture...ready for 3rd in nothin flat. Bet it would be really wild with big block power.
If you are removing a th350 the story is different. I have no expierence with that swap so cannot offer any difinitive insight.
I will say that thew 200R is a kick A trans when set up right. it works great for me with my 3.90 gears. Its through 1st and 2nd very quickly. Especially 2nd, 2nd is there and gone in no time. commin outa 1st@5500rpm and droppin into 2nd around 3500rpm....waaaaaa..sweet spot..you get the picture...ready for 3rd in nothin flat. Bet it would be really wild with big block power.
Burning Brakes
Joined: Dec 2001
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From: GA
Re: 700R4 Conversion Guys...Lessons Learned...Pros and Cons Please (Rick Church)
Alright now!!! You guys are makin me drool here :yesnod: I have way too much goin on right now to get involved with this mod but IT IS going to happen sooner or later. I think it's a must on my list along with alot of other mods like rear gears . You guys with 3.73 rears and the 700r4? are you happy with this setup? Stock 81's really suck by comparison although I do have smog removed and a/c gone but it is going back on and true duals. I fear that a thousand mods are in store for me. All in due time. Right now I am building a racing gokart with my son. Not racing but got it in a swap so he wanted to fix it up. Can't blame him I wanted to too :D but as soon as thats done it's back to the vette again. I have WAY TOO many projects going on but this is my first vette and I'll have it FOREVER!!! So I have plenty of time