Thread: 700r4 performance upgrades???

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hello, i just bought a 700r4 30 spline 2600stahl i bought it "rebuilt n very low miles...." we'll find out. anyhow. the guy says it has alto red line clutches b&m stage 2 shift kit, what im curious about is are there any upgrades i can do with out ripping the trans apart????? i dont know if it has a corvette servo? can i put a servo in without tearing it down?? are there any other smaller things that can b done??? (other then new valvebody, higher stahl, etc.) any info or help is greatly appreciated.

adam

The 700R has become a very popular transmission today. I always have to kinda laugh when I here that though. GM lists the 700R4 as a "Light Duty" transmission. For a performance car it is "NOT" a good choice because of the gear selections GM used in this transmision.

Ist gear in all 700R4's is 3.06 and then there is a huge jump to 2nd gear at 1.63. That is a 47% difference, compare that to a Muncie M21 4 speed, transmission were if you make the shift from 1st to "3rd" and skip second altogether that is only a 41% difference. The 700r4 was built and designed to help GM with its EPA rating. It does a good job on that front but at the cost of performance and durability.

Adam, I know this doesn't answer the questions you asked but if its not to late maybe you can reconsider your choice, and get a tranny that is more suited to performance work.

RS

Well, it all depends on what you have in mind for your car. According to the folks at Bowtie Overdrives a properly prepared 700R4 is a pretty good deal;

"They will handle a steady diet of around 450/500 hp and 400/450 ft/lbs. of torque. This Level Transmission is definitely a huge step up from what the popular brand name companies' offer (according to their descriptions) and they still charge more! We have sold thousands of this Level Transmission over the last seven years with tremendous success. This is our most popular Level Transmission with years of refinement that's proven to be very reliable and tough in serious street performance vehicles."

http://www.bowtieoverdrives.com

I have not used Bowtie, but hear good things about them and they seem to have a lot of good information on their site - you may want to check them out.

Good luck and welcome to Club Hotrod,
Glenn

The 700's that are behind 4.3's are light duty.We with Astro vans that do a V8 swap have just done a Trans-go shift kit,Vett servo,.05 boost valve,and tranny cooler.That tranny cooler is so important and I can't stress that more.The truck 700 V8 trannies on the other hand do have better clutch set-ups.If it where me with a unknown mods,cooler included,I would want a tranny temp gauge too.In reality mods intended for a race tranny don't do well in street use.Heat is the one item that causes failures.

The best upgrade to a 700R4 is installing a HD Sunshell in the rebuild. This is the weak spot of any 700R4.
Ask the guy who rebuilt the trans to make sure he put a HD Sunshell in it.



HD Sunshell

My two cent worth is TCI sells a killer heavy duty sunshell unit.

www.transmissioncenter.net

You name, they have it. All sorts of performance upgrades and parts

I have used the Bowtie Overdrive transmissions in several vehicles and I've had very good luck with them. For a heavy car the 700 works real well. The low first gear gets it rolling. I'm building a 427ci LSX that we figure will put out about 550hp. Bowtie built me a Stage 3 200 4R that should handle that. It's going into a light car - '32 Ford hiboy sedan. The gear spacing in the 200 4R is similar to a close ratio 4 speed, except of course it has overdrive.