i have a new converter which is conistantly showing a loss of 2-3mph in the 1/4. i have heard that you should get the car tuned after a converter install but will this allow me to regain my 2-3mph? i dont bounce of the limiter or anything it just doesnt put out the mph like it did before. and if mph is a measure of hp then i lost 20-30hp!!! anyway, could this be fixed with tuning or is this converter just less efficient than stock?

 

Depending on which convertor you have, your probably looking at deleting torque management, adjusting shift points, idle, and line pressure....Not sure if there is anything else.

Oh yeah throw a tranny cooler in there, nice and cheap insurance that will make your tranny extremely thankful. Look at a GVW of 24000 or 28000, something like that atleast. It'll cost you about 125 installed

 

Also some convertors are known for MPH losses. As long as your getting better ETs who cares?

 

i care when theres an old guy that i cant pass cuz theres too much traffic and im missing 20-30hp it takes to pass and still have a little buffer zone between me and the oncoming cars.
also, i have a tranny cooler but the tranny guy said i wouldnt need it. it stalls somewhere around 3200-3300 rpm

 

Keep the cooler hooked up anyway. It's almost impossible to overcool an auto so it won't hurt.Tuning should help. My vig 3200 lost me 2-3 mph but improved my 1/4 times by 4-5 tenths, and my 60 ft to a 1.7 from a 2.0. Worth it to me. The torque management will hurt you up top during wot shifts.

 

but does it hurt more when you have a converter? on a good note (for me anyway)i raced a car from a roll that traps 106 in the 1/4 to my 102 and i was creeping up on him at the top of third.
is there any other reason i could be losing mph other than efficiency loss?

 

IMHO ... Torque Management: The only reason these 4L60E's hang in there behind a 345 flywheel HP stock motor shifting at 6K is "Torque Management".

No body is putting so much torque to these things that they're busting teeth off gear sets ... there smoking clutches!

Torque Management waits till trany clutches are fully engaged before bringing back full power. Deprogram Torque Management and you'll smoke a little off your clutches every WOT shift, and we'll see you posting back here boo hooing about your 3-4 clutch going south.

Your PCM shift time needs to be tuned to your 4L60E clutch set up shift time.

I also believe a torque converter will only help your 60' ... My stock car comes out of the hole <2k, once the revs are up, they stay between 4400 - 6200 "the sweet spot"

... Ron