Engine/Transmission (1994 - 1998) How to read a torque plate chart

[BSMcCauley]

I'm finally considering a power up-rate and am trying to figure out which torque plate I want to try. However, I'm a bit confused and would appreciate some clarification on the following point: why does a #10 plate show 220 hp/570 ft-lb on the 96-98 auto transmission and 330 hp/750 ft-lb for the manual box for that same year? What else besides the torque plate is different on the engines set-up between these two applications? I want to avoid getting myself into trouble with stacking the wrong plate on an injector swap.

 

[JHenry]

The engines in front of the automatic transmission are powered down from the factory in comparison to those driving the manual transmission. I have a '98 12 valve with an auto. I used the TST #5 plate and am very pleased with the difference. I also put a triple disc torque converter and a new BD valve body in the trans.

 

[BSMcCauley]

The "powered down" part I understand, however I had been under the apparently incorrect assumption that they arrived at different power ratings with different torque plates. Does anyone know how the different power ratings were achieved?

 

[Woodenhead]

The manual transmission trucks have a 215 hp motor (you're auto is 160hp) which has a little bit different injection pump. The pump has a different grind on the cam that drives the plungers, different delivery valves and I think (but not 100% certain) bigger plungers/barrels. The 215 motors also have larger injectors. The 215 pumps respond better to the cam plate mods and yield larger hp increases. I believe the stock cam plates are the same in all of the pumps.



You may find certain injectors such as 370s with your auto (160hp) pump will cause a stumble at certain RPMS/loads and you'll need some different delivery valves.



Mike

 

[Joe G.]

The auto in '96 was 180 HP. I think the injectors were different than the ones on the 160.

 

[pwerwagn]

For Starters, your pump is a 180hp pump, not a 160 as previously noted.

Second, the stock plates in all the pumps are NOT the same, they each use a different plate.

180 and 215 pumps both use 181 DV's as well, 160 and 175 use 131's.



There are multiple differences between your 180 and a 215. 180's can make use of more rack travel than a 215 can. However, the 215 pump (I. E, 913/887) will provide more fuel with the same plate when compared to a 180 (885) pump.



As far as using the "wrong" plate with different injectors, thats not a concern. The only concern with some plate profiles is the use of gov springs, still not really a huge issue however.



--Jeff

 

[Woodenhead]

I need to not reply to posts at night . Thanks for the corrections guys. I guess my experience was with my buddies '95 which I think was 160hp, I forgot the '96 was different.



pwerwagn since he already has 181 DVs will he not run into the stumble issues that some auto guys run into with larger injectors?



So what is it that makes the plates respond better in the 215 pumps then?



Thanks,

Mike

 

[Vaughn MacKenzie]

So what is it that makes the plates respond better in the 215 pumps then?



Thanks,

Mike

Bigger plungers.



On the TST plate chart (here TST Power Kit without Video - IN) the lower the number the more aggressive the plate. The HP figures are flywheel, not RW horsepower.



Plates 5&6 are basically too aggressive for the 215 pump but good for all the others.



Plates 10-12 are good for the 215 pump but not recommended for the others because they're too weak to bother with.



Vaughn

 

[BSMcCauley]

Thanks to all. I hate breaking ground already plowed, so I appreciate the input.