Problem 200r4

1320chevy

Not-quite-so-new-guy
Jun 23, 2023
45
33
18
Bought an "exotic build" 200r4 transmission for our G body (85 montecarlo). Unit has all the bells and whistles offered. Special pump, special clutches, all thrust washers replaced with rollers, many hard parts custom made from billet or heavily modified. Valve body is of this companies own design and is supposed to be based upon the best oem but with many "secret" modifications. Converter was supplied by the same company and is supposed to be around 3000 stall with no lockup feature. OK, the problem is that the unit has never worked properly but being patient, we kept sending it back in hopes that they would make it work. (unit has been in and out of the car over seven times and NEVER has worked right. SO, WHAT'S THE PROBLEM? Well, it has finally sunken in that the shop that created it, is in way over their heads and simply don't have the knowledge base to draw from to make it work. The main problem is, this is a race car. During competition, the driver makes a shift at lets say, 6500rpm. The transmission does not respond. It does not slip and the rpms do not flair but keep going up as if the next gear had never been selected. Then, at random, it will shift. This is unpredictable with regard to rpm but always happens. You simply cannot depend upon it for any kind of consistency.. Yes, fluid is full and is not ever burned. The shop contends that this is impossible and that we are just wrong. We took this unit out of service and replaced it with a th350 and the problem is gone. so, it's not us or the car. This unit has cost us over $4,000 and I'd really like to have it working.
 
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1320chevy

Not-quite-so-new-guy
Jun 23, 2023
45
33
18
Engine is a 383 long rod with aluminium heads, Lunati Voodo cam and a performer air gap manifold, Bottom end is all forged parts and a good number of modifications to literally everything in the build. Diff id a 4:30 detroit locker It's an NA design with no adders. Making a guess, probably around high 400's hp based on trap numbers etc. One thing i"m still working out is that the acceleration curve seems to be like a rocket, then flattens out and in high gear runs like a pro stocker. Trying to un flatten mid range.





shifting is at about 5700 to 6000 depending on track conditions.
 

81cutlass

Comic Book Super Hero
Feb 16, 2009
4,618
13,457
113
Western MN
Not to throw water on the fire, but exotic parts in a 400hp capable 2004r seems unnecessary to me.

Thousands of light bolt on GN's make 400hp on stock/lightly freshened up BR auto valve body 2004r's. If you were making 800hp I could understand why you did what you did, but 400hp isn't exactly childs play, but its not exotic.

I just built a mild 2004r for my 4.1 buick turbo and besides some BR spec parts that didn't come in my CA code 305 chev 2004r, the only aftermarket parts I put in is a 3 friction OD, sonnax servo and stator, some pump springs, aluminum solid 3rd gear apply ring instead of the stamped steel part, and a Art Carr hardened 1/3 drum. Husek just drilled out some holes in my OEM valve body spacer plate and we run a stock BR valve body.

Why does a mild 400hp build 2004r need exotic rollerized parts, a full manual valve body, fixed line pressure? Heck 400hp doesn't even need a billet input shaft 1/3 drum.

It feels like EA sold you a premium product when you needed a solid moderate 'RV' setup. In my experience 2004r builders LOVE to upsell customers on stuff they don't need, everything is custom, they love to bash each other, each builder thinks their stuff is hot sh*t and most won't tell you why or what they do. It's just money in a black, trans shaped, box.

And it's a chevy. You could get a bone stock 4l80e with an aftermarket controller for under half of what you have in the 2004r. 2004r are great for BOP near-oem stuff without EFI but if its a chev man, going to a 2004r is a tough sell.
 
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1320chevy

Not-quite-so-new-guy
Jun 23, 2023
45
33
18
Not to throw water on the fire, but exotic parts in a 400hp capable 2004r seems unnecessary to me.

Thousands of light bolt on GN's make 400hp on stock/lightly freshened up BR auto valve body 2004r's. If you were making 800hp I could understand why you did what you did, but 400hp isn't exactly childs play, but its not exotic.

I just built a mild 2004r for my 4.1 buick turbo and besides some BR spec parts that didn't come in my CA code 305 chev 2004r, the only aftermarket parts I put in is a 3 friction OD, sonnax servo and stator, some pump springs, aluminum solid 3rd gear apply ring instead of the stamped steel part, and a Art Carr hardened 1/3 drum. Husek just drilled out some holes in my OEM valve body spacer plate and we run a stock BR valve body.

Why does a mild 400hp build 2004r need exotic rollerized parts, a full manual valve body, fixed line pressure? Heck 400hp doesn't even need a billet input shaft 1/3 drum.

It feels like EA sold you a premium product when you needed a solid moderate 'RV' setup. In my experience 2004r builders LOVE to upsell customers on stuff they don't need, everything is custom, they love to bash each other, each builder thinks their stuff is hot sh*t and most won't tell you why or what they do. It's just money in a black, trans shaped, box.

And it's a chevy. You could get a bone stock 4l80e with an aftermarket controller for under half of what you have in the 2004r. 2004r are great for BOP near-oem stuff without EFI but if its a chev man, going to a 2004r is a tough sell.
There are countless items that I use in a build that probably are unnecessary. That said, with the exception of this transmission, we don't have broken parts after every race session. Probably don't need a forged crank, rods and pistons, probably don't need a oversize driveshaft and huge joints with forged yokes and probably don't need a detroit locker. But what we need least of all are a ton of broken parts on the shop bench or all over the track. Nobody oversold the trans, it's exactly what I ordered but I ordered one that works.
 
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1320chevy

Not-quite-so-new-guy
Jun 23, 2023
45
33
18
There are countless items that I use in a build that probably are unnecessary. That said, with the exception of this transmission, we don't have broken parts after every race session. Probably don't need a forged crank, rods and pistons, probably don't need a oversize driveshaft and huge joints with forged yokes and probably don't need a detroit locker. But what we need least of all are a ton of broken parts on the shop bench or all over the track. Nobody oversold the trans, it's exactly what I ordered but I ordered one that works.
And, If I decided to put it on the bottle or another power adder, the most I'd likely need to change is the ring gap.
 

78Delta88

Royal Smart Person
Supporting Member
May 23, 2022
1,186
1
906
113
SW Arizona
Definitely nitrous or boost open the gap... But that's a given.

I plan to talk with Kelly see what advice he might have. I been working on 2004R for another here on the forum and biggest issue is finding all the stuff I need. I like to single source as much as possible and very difficult to do for this trans.
 

1320chevy

Not-quite-so-new-guy
Jun 23, 2023
45
33
18
Definitely nitrous or boost open the gap... But that's a given.

I plan to talk with Kelly see what advice he might have. I been working on 2004R for another here on the forum and biggest issue is finding all the stuff I need. I like to single source as much as possible and very difficult to do for this trans.
It is getting more and more difficult to source anything lately. Aside from "supply chain" stuff, I've been doing this so long that many of my solid long time connections are dying. Finding anyone who can do more than read a computer screen or even an instruction manual is nearly impossible. adding chinese knock off sub standard steel in parts to the mix, makes you want to just give up sometimes.
 

81cutlass

Comic Book Super Hero
Feb 16, 2009
4,618
13,457
113
Western MN
There are countless items that I use in a build that probably are unnecessary. That said, with the exception of this transmission, we don't have broken parts after every race session. Probably don't need a forged crank, rods and pistons, probably don't need a oversize driveshaft and huge joints with forged yokes and probably don't need a detroit locker. But what we need least of all are a ton of broken parts on the shop bench or all over the track. Nobody oversold the trans, it's exactly what I ordered but I ordered one that works.

If you got what you wanted, great. I wasn't intending to criticize your choices, more just that it seemed above and beyond what it probably needs and didn't know if you actively were a part of that decision or got talked into it.

I feel for you for sure. 2004r's are a nice party piece trans that make sense for many applications but the industry around them is frustrating.
 
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justdandy

Not-quite-so-new-guy
Jan 20, 2022
15
5
3
Freind my heart goes to you. I had a similar problem with a Jag I had. sold it. BUT yours is an "easy" fix, IMO. use a 7004r vs the 200 yes a horse power or to taken away but it works. I've found going 80% out is a smooth way to go over going full race. again sorry
 

justdandy

Not-quite-so-new-guy
Jan 20, 2022
15
5
3
if they used their own valve body then they re-engineered the hydraulic circuits there. could be something as simple as a stuck ball check till pressure goes up.
 
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