HP difference from a TH350 vs th2004r OD.
Thread Starter
Race Director
Joined: Apr 2007
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From: Henderson Nv-Rohnert Park/Sonoma C o. ca/born in NY Rockaway Beach.
HP difference from a TH350 vs th2004r OD.
OK so I thought id start a thread to find out what difference if any in HP rating going from a th350 to a th2004r...
Im getting ready to order my trans from BTO and going to pick it up at a Good Guys car show at the end of the month to save on shipping cost and tax.. So just curious if ill gain any HP ..
Im getting ready to order my trans from BTO and going to pick it up at a Good Guys car show at the end of the month to save on shipping cost and tax.. So just curious if ill gain any HP ..
Pro
Joined: Feb 2012
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OK so I thought id start a thread to find out what difference if any in HP rating going from a th350 to a th2004r...
Im getting ready to order my trans from BTO and going to pick it up at a Good Guys car show at the end of the month to save on shipping cost and tax.. So just curious if ill gain any HP ..
Im getting ready to order my trans from BTO and going to pick it up at a Good Guys car show at the end of the month to save on shipping cost and tax.. So just curious if ill gain any HP ..
Hard to compare those two transmissions but the BTO guys can build several levels of power handling with the TH200 and I highly recommend that option over the TH350 simply for the direct swap in and OD gearing.
Thread Starter
Race Director
Joined: Apr 2007
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From: Henderson Nv-Rohnert Park/Sonoma C o. ca/born in NY Rockaway Beach.
I already have a 200r stage 2 on order.. the question is what HP gain will I get from swithching from the th350 to the 200r...
Pro
Joined: Feb 2012
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HP gain? A transmission isn't a power adder. It's a power loss. The better question might be which transmission loses more power as it travels back through the drive train. I would guess the TH200 loses more power than the TH350 but not much and certainly not noticeable. The TH200 has very similar gearing to the TH350 so your car will feel almost the exact same in gears 1 - 3 and then you have the added 4th gear and OD. Obviously you know the gains from installing an OD transmission but HP is not one of them.
Thread Starter
Race Director
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From: Henderson Nv-Rohnert Park/Sonoma C o. ca/born in NY Rockaway Beach.
Yes HP gain.. from what I have heard going from a TH350 to an OD TH2004r doesnt steal the 15-20% hp the 3speed does..
Pro
Joined: Dec 2004
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From: Mitchell SD
X2 The 2004r internals are lighter weight and take less hp. to turn. They made them legal to run in stock eliminator drag cars even if the car came factory with a different trans. There is a racer from Minnesota who races a mid 70's rubber bumper vette who took over a tenth off his et. just by changing from a th350 to a 2004r.
Thread Starter
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From: Henderson Nv-Rohnert Park/Sonoma C o. ca/born in NY Rockaway Beach.
X2 The 2004r internals are lighter weight and take less hp. to turn. They made them legal to run in stock eliminator drag cars even if the car came factory with a different trans. There is a racer from Minnesota who races a mid 70's rubber bumper vette who took over a tenth off his et. just by changing from a th350 to a 2004r.
Guess ill find out after I do the swap.. Ill have it dynoed at a dyno day to see the difference..
Le Mans Master
Joined: Sep 2004
Posts: 5,116
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From: Livonia MI
All automatics sap some engine power to run the internal hydraulic pumps, and there's gear/bearing friction in any kind of tranny. As mentioned, larger mass designs, like TH-400's sap a little more. Don't think there's much difference between a TH-350 or 200-4R though. Keep in mind, the numbers you mentioned are for the entire driveline, from engine output shaft to rear wheels. General rule of thumb, is 15% total driveline loss for manual trannys, and 20% for autos. None of this is etched in stone though.
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Drifting
Joined: Aug 2005
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From: League City TX
They are 3 speed transmissions.
I have never seen them do an od swap, though I guess someone may have tried it.
Le Mans Master
Joined: May 2006
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From: League City Tx
X2 The 2004r internals are lighter weight and take less hp. to turn. They made them legal to run in stock eliminator drag cars even if the car came factory with a different trans. There is a racer from Minnesota who races a mid 70's rubber bumper vette who took over a tenth off his et. just by changing from a th350 to a 2004r.
I am sure you could see a tenth reduction and gain atleast 1 mph at 3500lbs....thats the equivalent to 15-20hp..... not to mention you get a lower first gear (2.75 vs. 2.52)... If your engine is a little soggy on the bottom end, this will help you out even more. Seat of the pants should feel better.... actual gains on the street will likely be minimal.
If the T350 is still in the car, go spin it on a chasis dyno and see what you end up with.... Then when the 200R4 goes in, go spin it again and see what you gained....It will be a neat experiment.
I will likely be switching to a 200R4 myself in the next year or so.... The best thing about the 200r4 is the lock up converter.... You can get you a really increased stall speed for great launches yet when it locks up on the street it will feel like stock...
Thread Starter
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From: Henderson Nv-Rohnert Park/Sonoma C o. ca/born in NY Rockaway Beach.
Great info. exactly what I was looking for.. I know its not much of a gain, but every little bit helps...Look slike this will get in the mid to hi 13's then.. not that I go to the track much anymore, But I will do a few pulls with the new trans at some point
I have my dyno from this set up already .... once I swap to the 200r ill have another dyno done just to see results....
thanks for the info..
I have my dyno from this set up already .... once I swap to the 200r ill have another dyno done just to see results....
thanks for the info..
+1
I am sure you could see a tenth reduction and gain atleast 1 mph at 3500lbs....thats the equivalent to 15-20hp..... not to mention you get a lower first gear (2.75 vs. 2.52)... If your engine is a little soggy on the bottom end, this will help you out even more. Seat of the pants should feel better.... actual gains on the street will likely be minimal.
If the T350 is still in the car, go spin it on a chasis dyno and see what you end up with.... Then when the 200R4 goes in, go spin it again and see what you gained....It will be a neat experiment.
I will likely be switching to a 200R4 myself in the next year or so.... The best thing about the 200r4 is the lock up converter.... You can get you a really increased stall speed for great launches yet when it locks up on the street it will feel like stock...
I am sure you could see a tenth reduction and gain atleast 1 mph at 3500lbs....thats the equivalent to 15-20hp..... not to mention you get a lower first gear (2.75 vs. 2.52)... If your engine is a little soggy on the bottom end, this will help you out even more. Seat of the pants should feel better.... actual gains on the street will likely be minimal.
If the T350 is still in the car, go spin it on a chasis dyno and see what you end up with.... Then when the 200R4 goes in, go spin it again and see what you gained....It will be a neat experiment.
I will likely be switching to a 200R4 myself in the next year or so.... The best thing about the 200r4 is the lock up converter.... You can get you a really increased stall speed for great launches yet when it locks up on the street it will feel like stock...
275, 350, difference, gain, handling, horsepower, kit, performance, power, ratings, sale, th200, th2004r, th350, transmission, weight
