200R4 vs TH400
- Thread starter fastjay71
- Start date
Pro...It could take a scud to the casing and come out polished.
Con....loss of overdrive and fun on the highway. Of course you could always spend another $2K at Gearvendors for OD.
200's are taking 9 second passes. Properly built ones go 10's and are used as daily drivers. We have better parts, better builders now. I wouldn't be afraid of keeping a 200.
Con....loss of overdrive and fun on the highway. Of course you could always spend another $2K at Gearvendors for OD.
200's are taking 9 second passes. Properly built ones go 10's and are used as daily drivers. We have better parts, better builders now. I wouldn't be afraid of keeping a 200.
blackplague
Are you watching Phil?
- Joined
- May 25, 2001
With all the parts
and the builders on this board, it souldn't be necessary to go to a 400.
Mike.
and the builders on this board, it souldn't be necessary to go to a 400.
Mike.
boostingbuick
Going to be buried in this.
- Joined
- Aug 25, 2002
I like my 200r4 even if its not as strong as a 400. And my cost more to build it strong, but I have od and I think after the years and the cost of gas I will be getting close. But if just a race car, I can agree with the 400.
to be truthful honest with you . Driving around my reverse manual TH400 on the street is alot more fun then it was with the 200R4 . That alone outweights IMO the extra gas I may use .
Hi Folks,
One thing concerns me that I almost never hear about: what is the parasitic power loss to the motor to drive a "built" 400 and a "built" 200R4?
I've heard scary numbers like 60hp for the 400 at 6krpm - is that true? And what about for a 200R4 built to be durable in a car that can go 10's?
(The logic goes as follows: the faster the car, the higher the average torque input to the transmission. This means that clutch applications during shifts must absorb a higher impulse (integral of Fdt.) If the application time is conserved, then the application forces must be higher, which implies a higher pump pressure. Since p =F.v, this means more input power to drive the pump, and so we lose more power from the motor to operate the transmission.)
More than one really, really smart engineer has tried to talk me to go back to a manual transmission for this reason alone.
Best,
MAP
One thing concerns me that I almost never hear about: what is the parasitic power loss to the motor to drive a "built" 400 and a "built" 200R4?
I've heard scary numbers like 60hp for the 400 at 6krpm - is that true? And what about for a 200R4 built to be durable in a car that can go 10's?
(The logic goes as follows: the faster the car, the higher the average torque input to the transmission. This means that clutch applications during shifts must absorb a higher impulse (integral of Fdt.) If the application time is conserved, then the application forces must be higher, which implies a higher pump pressure. Since p =F.v, this means more input power to drive the pump, and so we lose more power from the motor to operate the transmission.)
More than one really, really smart engineer has tried to talk me to go back to a manual transmission for this reason alone.
Best,
MAP
Robert Wilson
Member
- Joined
- May 26, 2001
I was concerned about the parasitic loss but went ahead with the change to a 400 anyway. All I can say is I am glad I did.
With no change to my engine combo after the change to the 400, I would say my ET and MPH stayed the same. I have actually improved my previous best 10.62 @ 126MPH with the 200R4 to a 10.55 @ 126.8MPH with the 400.
I know my comparison is not a controlled test but I would say it would rule out a 60 HP difference.
BTW, Engine combo is stock crank 109 block, ported irons, 218 hydraulic flat tappet and an old T64 P Trim turbo.
Robert
When I changed over to the 400, I lost maybe a tenth. My situation wasn't a controlled one either, as I had made a few other changes at the same time. I am much more relaxed when I go racing though, not having to think about the trans giving up on me.
There is a point where you should go with a 400 rather than trying to stick with the 200-4R. I put the HP level at 650. I know some have claimed they can build a 200-4R that will stand up to 1100HP. I'm sure it will... for awhile. Will it be long enough to make it worth the big dollar parts inside?
There are some other limitations that aren't discussed very often about the 200-4R besides just the hard parts that make switching to a 400 a smarter choice in a high HP situation. MAP touched on it a little.
There is a point where you should go with a 400 rather than trying to stick with the 200-4R. I put the HP level at 650. I know some have claimed they can build a 200-4R that will stand up to 1100HP. I'm sure it will... for awhile. Will it be long enough to make it worth the big dollar parts inside?
There are some other limitations that aren't discussed very often about the 200-4R besides just the hard parts that make switching to a 400 a smarter choice in a high HP situation. MAP touched on it a little.
I'm on my 4th rebuild in 10 years and this will be the last as no one it seems can build a 200 to hold up to a low 11-high 10 sec car. Please understand I only make about 15-20 passes a year with this car, the rest of the time it is on street tires where I only drive 1-3K a year. With this rebuild I have over $5000.00 in this transmission. I'm doing this through a friend as the last three "Gurus" did not build what I thought I was buying and could not make it shift like it did when you drive a low mileage T. I have found this guy who has been building custom trannys for 30 years here locally who says he can give me back that feel but says these trannys can't live behind power levels over 400 horsepower in a full weight Regal for very long. Maybe there is someone out there who can build one but I haven't found him and no one else I know who drives these things has either. He says he will gaurantee a TH400 in my car but not the 200. Anyway he will have it finished up next week and I will post how successful he is at giving me back those quick, crisp shifts. He has some very interesting philosophies on these trannys and I am going to let him try them out. If his ideas work I will sell this trans before I ruin it and go to a 400 with a gear vendors overdrive.
I am not trying to start trouble or calling anyone a thief or liar. I personally have had mine built by three separate "Gurus" and all three rebuilds did not live very long (one less than 500 miles). Like I said maybe there is someone out there who can build a 200 stout enough for a 10 sec car but I haven't found him and neither has the any of the people I know personally. I just can't afford to keep trying a new builder every year or two until maybe I find that special someone who can build what I think I'm buying.
Mikey
I am not trying to start trouble or calling anyone a thief or liar. I personally have had mine built by three separate "Gurus" and all three rebuilds did not live very long (one less than 500 miles). Like I said maybe there is someone out there who can build a 200 stout enough for a 10 sec car but I haven't found him and neither has the any of the people I know personally. I just can't afford to keep trying a new builder every year or two until maybe I find that special someone who can build what I think I'm buying.
Mikey
well as I said to Russ Merritt "I am from Missouri SHOW ME" we have one tranny here with a Art Carr drum, shift kit, 10 V pump, and a bigger servo.. Melissa ran that for a while WITHOUT LOCKING THE CONVERTER. worked great !! many LOW 10 runs @ 133 ish and a LOT of street driving .. Last year we set it aside to keep as a backup . Russ built another one with the good "Junk" in it didn't miss a beat all year 9.9 to 10.3s @ 138+ all year except BG (didn't have any brakes to hold the car on the line ) Car is DRIVEN all over the place!! So have to give Russ the "atta boy" for the one he did for Melissa and the back up one!! That will be in the Mazda :biggrin: Can they break ???? hell ya !!! anything can and will break sooner or later IF you can't get a 200 to live in an 11 sec car your not a "professional" :redface:
didn't miss a beat all year 9.9 to 10.3s @ 138+ all year except BG (didn't have any brakes to hold the car on the line ) Car is DRIVEN all over the place!! So have to give Russ the "atta boy" for the one he did for Melissa and the back up one!! That will be in the Mazda :biggrin: Can they break ???? hell ya !!! anything can and will break sooner or later IF you can't get a 200 to live in an 11 sec car your not a "professional" :redface: Hi Folks,
Interesting discussion. I know very little about transmissions, but my guess is that the impulsive loading during firm shifts probably kills more tranny's than high-output motors per se, and that through hard-parts failures; that is, the metal is stressed beyond its yield or fatigue strength during the rapid change in engine momentum at the moment of the shift, and voila, broken parts.
Since impulse is conserved, the solution here would be to make the shift softer to reduce peak loading, but then my guess is that soft-parts wear becomes the dominant failure mechanism.
If we have to choose between the two, soft-parts wear and failure are better, right?
Thanks,
MAP
Interesting discussion. I know very little about transmissions, but my guess is that the impulsive loading during firm shifts probably kills more tranny's than high-output motors per se, and that through hard-parts failures; that is, the metal is stressed beyond its yield or fatigue strength during the rapid change in engine momentum at the moment of the shift, and voila, broken parts.
Since impulse is conserved, the solution here would be to make the shift softer to reduce peak loading, but then my guess is that soft-parts wear becomes the dominant failure mechanism.
If we have to choose between the two, soft-parts wear and failure are better, right?
Thanks,
MAP
Can they break ???? hell ya !!! anything can and will break sooner or later
I don't expect them to last as long as a daily driver. And I agree that once you start closing in on the 10's breakage is going to have to be figured in your budget but I don't abuse the tranny either. I use a line lock to lock out the rear brakes when I heat the tires in the water box. I launch a 4-5# boost against the brakes on drag radials. On the street it is on street tires that get blown away if you build any real boost under 40 mph as you know with your cars. I run a large engine oil cooler as a trans cooler and don't use the radiator cooling circuit and my trans temp gauge (on the return line) only closes in on 240 at the end of the strip otherwise it is withing acceptable levels. So what am I doing wrong (unprofessional)? I can't get more than
2-3K out of a tranny with maybe 30-35 passes on it. That is not acceptable.
Mikey
boostingbuick
Going to be buried in this.
- Joined
- Aug 25, 2002
Been there and done that. I hated my 200 for years. One guy make it last for 3 months, the next for weeks. Never shifted right, flared on shifts and shifted too soft. After I found someone to do it right I will say that I am very happy. You can't have just any trans guy build it. You need someone who understands what your going to do with it and how to get it there. I am running high tens at 128 at the track and street drive it everywhere. The only thing after it was done right was having to put a trans cooler on it to keep it cool. I have 40 passes and 4k miles in it since the last build. I know it won't last forever, but I like my overdrive since I like going fast on the e-way. Its just like building an engine, build it right and it will be happy. You would not put a Autozone engine in and think it will make 40 ten second passes. But you also don't need to buy billet everything for it to live.
turbo nasty
Turbo Dojo / MNTR
- Joined
- Jul 19, 2001
600 hp and a 2004r or 4l60e/700r4 is on the edge. There maybe a few folks that are having luck but droves of others are not at this HP and higher.
boostingbuick
Going to be buried in this.
- Joined
- Aug 25, 2002
520 to the wheels and 40 passes. I think builder has more to do with it than luck.
