I'm in the process of building a 406 that is going to make big power 700+. And i'd like to keep my 700R4 if at all possible. are there are parts on the market that will actually make the trans "stronger" and "Reliable"? then I'll do that, other wise I'll be forced to go to a turbo 400 which I dont want to do.

 

If your making an honest 700HP why even consider a 700R4? I'm sure you could find someone who claims to sell a 700R4 capable of 700HP but why bother spending $2000+ (not including converter) on something that might blow up anyway? You could build an unbreakable TH350 or 400 AND buy a top quality torque converter for less than it would cost you to buy a 700R4 that may still even break.

 

one word................NO!!!!!!!!!!!!!! It will be more reliable but won't handle 700 hp.

 

If you are set on a 700R4 for that power, you could probably use a TCI Super StreetFighter with a full manual valve body. That means no automatic capability. You shift it yourself, just with no clutch. It won't last forever, but it should last you a while.

 

If your dead set on an overdrive tranny you might consider the 2004R like out of an 86-87 Grand National/Turbo-T.Many people will tell you the 2004R is weaker than the 700R4 but the numbers say otherwise,as there are many a 9-10 second turbo buick running them - and we're not talking about lightweight race cars either,more like 3500lbs bricks making 700-800+ hp and equal or more torque.

I will warn you though,they are expensive but they'll outlast a 700R4

HTH,
Steve

 

I would agree... I've seen some very fast turbo buicks with 200's in them. But what exactly is your reasoning for wanting to keep the 700R4 in the first place?

 

The 200R4 is weaker than the 700R4 in stock form. But it responds better to bulletproof parts than the 700R4.

 

why screw around with those when you can build up a 4L80E transmission. You'll get overdrive and TH400 strength. Of course you'll need a controller for it, but it'll be worth it if you're spending the bucks to go fast.

 

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Thanks for all the info I really appreciate it. The reason I was asking about the using the the 700 is for one, I already have one that is fairly modified, and two i'm not real high on the horse about using a three speed. But I guess there are sacrafices we need to make to the speed and power gods.

 

I agree with the 4L80E suggestion.

The 2004R lives a long time behind the turbo Buick, but consider how a turbo Buick makes power, especially a 10 or 9 second car. It's a turbo motor. It makes no torque off the line. All the power comes once the motor is spooled up and under load. Even if you load the motor into the converter at the line it isn't the same as real engine load. It isn't uncommon for turbo cars not to see full boost until 3rd gear. There are also a lot of heavy duty parts for the 200R4, specifically because of the Buick market.

I don't think the 700R4 will live up to this kind of power for long. I'd sell it while it still works and can command a good price, and then shop for a 4L80E.

The 4L80E is totally electronically controlled, so you need a stand alone ECU for the trans. Typically they use an ECU from a Diesel truck, which has no engine management portion of the ECU, and reprogram it for higher shift points and crisper shifts.

 

LOL no offense but you have no idea about turbo buicks do you?I'll take it you havent spent much time around them.Turbo buicks typically make 100-150 MORE torque than horsepower and most turbo buick racers are set up to launch with plenty of power,either with proper stall converters or trans brake(they make several for the 2004R including a fully automatic electronic unit).Most all of the 9-10 second turbo buicks 60ft in the 1.3-1.4 range and at an average weight of 3600lbs it takes quite a bit of torque off the line to do that I myself run 26-27psi of boost max and LAUNCH with 22psi(aprox 4200 rpm),enough torque to get my 3.08 geared, 3550lbs car to the 60ft in 1.47 seconds.

Everything you said might be true if we were talking about Supra's or RX7's but your way off on a Turbo Buick.

Steve

 

once it's installed your done with it. I agree with above that you can use a stand alone ECU from a diesel or buy a controller, but right now they run around $650 for a cheap controller and move up from there to $1350 for the last controller that intigrates into labtop software along with a DFI system that i am thinking about.

 

i dunno about the 4l80E? That seems like another can of worms, with having a seperate controller, I dont like that idea. If not a th400 how about a T-56 out of a viper? would those be good for 700+?

 

I cast my vote for a heavily built th400 manual valve body and then bolt a Gear Vendors overdrive to the back of that. This is what I did for my Vette and it is awsum! The only way to fly. It'll cost you about the same as a good 4l80e/controller. But, it will be lighter and much cheaper to rebuild if you ever do break the th400. Don't even consider breaking the Gear Vendors. It won't. If you did break it in the first two years they will give you a new one. If you break it after 2 years they will replace it with a new one for $500. No questions asked. Pretty good plan I would say. I think they don't end up doing this very often tho. You can take a look at my web site for a bit more info on this. I have a page dealing with the conversion on the Vette. In a 3rd gen the conversion would be way simpler since you have a cross member which the Vettes don't. Good luck.

 

ive alays heard that the 700R4's are almost exactly the same as the TH400, just with overdrive and a few other things.

Oh well, just what I heard. I have heard that there are people at the local track runnin 700s in their camaros with about 550-600 horses...I know thats not 700 but hey pretty good!

cheers ya'll

 

TTA850, I know plenty about turbo Buicks, and plenty about turbo motors in general. When I first bought my WRX I did a lot of research about turbo systems and how they make power. The fact is the turbos are always easier on parts than either NA engines or supercharged engines of the same power level. I don't debate that the engines make more torque than horsepower, that's got nothing to do with what I said. Turbos build increasing power from the point where boost first starts to build. They don't shock load parts with instantaneous torque the way an NA or blower motors does, and that's why they are easier on trannies and rears. I bet a 700R4 would do fine behind a 9 second GN, and that's the point I was really trying to make.

A TH400 with the Gear Vendors unit would work well too. Not surea bout the cost vs the 4L80E though. I'd research that if I were you.

The 700R4 is more like a TH350 than a TH400. The 4L80E is like a 400 with overdrive an electronically controlled shifting. Pro-Built rates his 700R4 rebuild kits to like 575 horses I think, so it is possible to have them live up to this level of power, but 700 would really be pushing the envelope.

 

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Sure, you can click on the little box that says "www" in my signature area or click on this: http://www.corvetteforum.net/c5/bob86zz4/

Thanks.

 

I vote to take all the guess work out of it and just call Dana from Pro-Built Automatics up. www.pro-built.net

He can even sale you a kit to have installed in your current trans to upgrade it to one of his high hp holding trans.

He just started building the 350s and 400s again also.

 

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Don't you see a row of boxes along the bottom of my post that say: "Profile" "PM" "email" "www" "search" "buddy" ??? That's what I see across the bottom. I dunno. Maybe something is wrong with my profile or something if nobody else sees it.

 

bob i see it.....that kid is a little slow. :lala:

 

They're both little rats. They'll never be able to wip the olde man. The older one has his permit now and loves driving the Vette.

 

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somewhere i heard you have to modify the tunnnel to get a 4l80 in these cars??? not sure though really, i know they are big, my 3500 chev has one in it....my buddy says he can build a 4l80 totally manual without the need for a controller.... here are some links for 700's and 4l80's
http://www.transmissioncenter.net/700MegaRaptor.htm

http://www.transmissioncenter.net/4L80E.htm

 

You won't really know how much power you are pushing until you get the engine on a dyno, so maybe it won't be 700+ HP.

 

i'll have plenty of boost and nitrous to make 700. And a foundation to hold it.