Trany pressure test
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From: Lantana TX
Trany pressure test
Hey foks.. My new TCI 10" (3000) stall converter is stalling around 6K when I floor it off the line, but fine at part or half throttle. Someone mentioned the trany pressure may be down , which would cause a high stall to happen. Trany is a 350 rebuilt a few years ago.
I was about to just buy a new trans, but not knowing why this is happening is killing me. Plus if I can find out why you folks will help me save $1000 bucks.
How can I perform the test as I have a pressure testing kit.
Thanks in advance.
I was about to just buy a new trans, but not knowing why this is happening is killing me. Plus if I can find out why you folks will help me save $1000 bucks.
How can I perform the test as I have a pressure testing kit.
Thanks in advance.
Intermediate
Joined: May 2004
Posts: 45
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From: cedar creek tx.
You are probley over powering the converter if it is truly stalling that high. Or at most they sent you a really cool stall converter.
2nd gues! first gear is really wasted in wich case the car would not move anyway.
3rd gues you really have no idea of reality and this is a figment of your 530hp and 530tq with a 218/228 cam. And i suspect this is all with cast crank stock rods and right. So let me give a question back is that rear wheel hp and torque or motor? and what kind of dyno? and most important how fast? Low pressure in a t350 with 530 hp means bad clutches and band if it doesn't have a trans brake.
2nd gues! first gear is really wasted in wich case the car would not move anyway.
3rd gues you really have no idea of reality and this is a figment of your 530hp and 530tq with a 218/228 cam. And i suspect this is all with cast crank stock rods and right. So let me give a question back is that rear wheel hp and torque or motor? and what kind of dyno? and most important how fast? Low pressure in a t350 with 530 hp means bad clutches and band if it doesn't have a trans brake.
Last edited by 377vette; Oct 12, 2006 at 09:42 PM.
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From: Lantana TX
Originally Posted by 377vette
You are probley over powering the converter if it is truly stalling that high. Or at most they sent you a really cool stall converter.
2nd gues! first gear is really wasted in wich case the car would not move anyway.
3rd gues you really have no idea of reality and this is a figment of your 530hp and 530tq with a 218/228 cam. And i suspect this is all with cast crank stock rods and right. So let me give a question back is that rear wheel hp and torque or motor? and what kind of dyno? and most important how fast? Low pressure in a t350 with 530 hp means bad clutches and band if it doesn't have a trans brake.
2nd gues! first gear is really wasted in wich case the car would not move anyway.
3rd gues you really have no idea of reality and this is a figment of your 530hp and 530tq with a 218/228 cam. And i suspect this is all with cast crank stock rods and right. So let me give a question back is that rear wheel hp and torque or motor? and what kind of dyno? and most important how fast? Low pressure in a t350 with 530 hp means bad clutches and band if it doesn't have a trans brake.
Your comments---
“3rd guess you really have no idea of reality and this is a figment of your 530hp and 530tq with a 218/228 cam. And i suspect this is all with cast crank stock rods and right.”
I hope your seriously kidding and not one of those idiotic members that we all run into from time to time. If you’re not, this is a year one crate motor and yes I have the dyno sheet to prove it. Also, if you look at my signature a 125 shot of NOS is included in my specifications. So realistically, the motor at the crank is 430 hp and 430 tq. RWH, I am assuming 325-340 since I have not yet placed it on a dyno since it has been installed. I have not yet used the NOS on this motor simply because of the issues that I am having.
If you want to see more about the motor read this:
http://www.yearone.com/serverfiles/f...ain2.asp?cat=Q
If I have miss understood your comments then ignore mine.
Race Director
Joined: Jul 2004
Posts: 12,684
Likes: 329
From: Scottsdale Arizona
Originally Posted by 76 sting
How can I perform the test as I have a pressure testing kit.
If you want to test the line pressures, the test plug is located on the passenger side, just behind the accumulator (big, round thing). The specs for the test procedure are pretty involved, but, based on a TH350C, the line pressure at idle, in drive (brakes applied) should be around 62 PSI. At 1200 RPM, it should be up to 150 PSI.
Interestingly enough, if you follow the same procedure but use reverse, idle should be 86 PSI and 1200 RPM should be 250 PSI.
This should work as a starting point at least.
Good luck!
Last edited by CA-Legal-Vette; Oct 13, 2006 at 12:36 AM.
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From: Lantana TX
Originally Posted by CA-Legal-Vette
I looked up the testing procedure in the AST manual ( the procedure is pretty simple) but your symptoms sound more like a misadjusted detent cable.
If you want to test the line pressures, the test plug is located on the passenger side, just behind the accumulator (big, round thing). The specs for the test procedure are pretty involved, but, based on a TH350C, the line pressure at idle, in drive (brakes applied) should be around 62 PSI. At 1200 RPM, it should be up to 150 PSI.
Interestingly enough, if you follow the same procedure but use reverse, idle should be 86 PSI and 1200 RPM should be 250 PSI.
This shuld work as a starting point at least.
Good luck!
If you want to test the line pressures, the test plug is located on the passenger side, just behind the accumulator (big, round thing). The specs for the test procedure are pretty involved, but, based on a TH350C, the line pressure at idle, in drive (brakes applied) should be around 62 PSI. At 1200 RPM, it should be up to 150 PSI.
Interestingly enough, if you follow the same procedure but use reverse, idle should be 86 PSI and 1200 RPM should be 250 PSI.
This shuld work as a starting point at least.
Good luck!
However, you mentioned a misadjusted detent cable?? Can you explain little further, maybe I am missing something?
Part throttle, half throttle, all is perfect shifts great through the gears manually or in auto. Actually, when it stalls at 6K this happens only because I have a rev limiter at 6K through the disty. It hits 6K... limiter activates, and a second later the stall kicks in.
I can only hope it is the detent cable..
Race Director
Joined: Jul 2004
Posts: 12,684
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From: Scottsdale Arizona
Originally Posted by 76 sting
Thanks for the info. and your assistance.
However, you mentioned a misadjusted detent cable?? Can you explain little further, maybe I am missing something?
Part throttle, half throttle, all is perfect shifts great through the gears manually or in auto. Actually, when it stalls at 6K this happens only because I have a rev limiter at 6K through the disty. It hits 6K... limiter activates, and a second later the stall kicks in.
I can only hope it is the detent cable..
However, you mentioned a misadjusted detent cable?? Can you explain little further, maybe I am missing something?
Part throttle, half throttle, all is perfect shifts great through the gears manually or in auto. Actually, when it stalls at 6K this happens only because I have a rev limiter at 6K through the disty. It hits 6K... limiter activates, and a second later the stall kicks in.
I can only hope it is the detent cable..
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From: Lantana TX
Originally Posted by S489
are you confident that the torque converter is not the problem?
If i can't figure this one out I may just by a new TCI trany like the 350 Super Streetfighter with a 2.75 1st gear ratio, which is much better than the stock ratio. I guess it is like purchasing the 2004R with out the OD. I was told they have the same ratio, but not too sure.
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Racer
Joined: Mar 2006
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From: Ocean City MD
I would check your pressures first. You stall to 6K could also be slip in the trans. The detent cable or kick down will have nothing to do with that unless you were running a 700r4 or 2004r. You can go to TCI for pressure specs:
http://www.tciauto.com/Products/Tech...sure.asp#TH350
Odds are it is time for a mild overhaul. Pick-up some alto red clutches from Bulkparts.com and freshen it up. It is an easy job with the right tools.
http://www.tciauto.com/Products/Tech...sure.asp#TH350
Odds are it is time for a mild overhaul. Pick-up some alto red clutches from Bulkparts.com and freshen it up. It is an easy job with the right tools.
Race Director
Joined: Jul 2004
Posts: 12,684
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From: Scottsdale Arizona
Originally Posted by 76 sting
If i can't figure this one out I may just by a new TCI trany like the 350 Super Streetfighter with a 2.75 1st gear ratio, which is much better than the stock ratio. I guess it is like purchasing the 2004R with out the OD. I was told they have the same ratio, but not too sure.
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From: Lantana TX
Originally Posted by windsoreight
I would check your pressures first. You stall to 6K could also be slip in the trans. The detent cable or kick down will have nothing to do with that unless you were running a 700r4 or 2004r. You can go to TCI for pressure specs:
http://www.tciauto.com/Products/Tech...sure.asp#TH350
Odds are it is time for a mild overhaul. Pick-up some alto red clutches from Bulkparts.com and freshen it up. It is an easy job with the right tools.
http://www.tciauto.com/Products/Tech...sure.asp#TH350
Odds are it is time for a mild overhaul. Pick-up some alto red clutches from Bulkparts.com and freshen it up. It is an easy job with the right tools.
Could this very well be a symptom of a clutch starting to go? Would I typically find some metal shavings in the trans pan because I did?
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From: Lantana TX
Originally Posted by CA-Legal-Vette
The 200-4r has the same 2.75 first gear as the modified 350. I haven't really noticed the difference in gearing but I did the stall converter. Mine is around 2200 and made a pretty big difference.
I do not know anything about rebuilding them, but I can replace one pretty easy.
Has anyone ran the Super Streetfighter trany from TCI?
Racer
Joined: Mar 2006
Posts: 309
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From: Ocean City MD
I will say that I just installed a TCI comp trans in a big block Nova and it shifts great. However for a 1/3 the price I built a th350 for a friends tubbed big block 69 camaro that is just as strong. The answer is yes the trans will hold up. Go to this link and read over it:
http://www.nastyz28.com/forum/showthread.php?t=53671
With good clutches, good clearances, and a good shift kit you trans will hold up.
http://www.nastyz28.com/forum/showthread.php?t=53671
With good clutches, good clearances, and a good shift kit you trans will hold up.
Last edited by windsoreight; Oct 15, 2006 at 02:00 PM.
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From: Lantana TX
Originally Posted by sperkins
Any update?
Funny you mention this... I just ordered a 350 trany from Phoenix transmissions out of Tx. I figured that I would start from scratch since this was the stock trans but I was told it was rebuilt. If i start from scratch at least I know know what I am getting.
Update to come in 2 weeks when I finally install it.
I am also replying to you recent Dyno sheet request from Year one and it should be posted shortly.
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Joined: Jun 2004
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From: Lantana TX
Trany update
Originally Posted by sperkins
Any update?
However, I now an concerned with the new trany as I expected to have some very hard shifts, but I do not. When it shifts it happens soooo fast I can't even feel it. It shifts in a half a second or less? I think this is good but no neck snapping of gears which may also be a good thing, but I am not too sure. I have a 2800 -3000 10" TCI stall and was wondering if this was the reason why?
Signed.....Very confused
