So i took my car to the track last night, and felt like driving it into a ditch on the way home ( of course with me not being in it when it went in)..No but, Originally my car went 12.9 @ 110. this was with the following mods

- MTI airlid

_ pacesetter longtubes and off road y pipe, and a cutout

-dragradials

-stock gearing 3.23's

now i add a performabuilt tranny stage 2 with a 3400 stall performabuilt convertor and i launched at 1500 rpms ( tried all the methods, this worked best) and left the line with a 1.82 60', ran a 12.8 at 105 repeatedly over and over. love the stall and tranny BUT i thought i would hit mid 12's or atleast a 12.6. Im on stock suspension and a ls1 intake manifold. Do i need to up the gears? LCA's? LS6 manifold? Hook a space shuttle on the back of my car?what the hell is going on here?

any advice from fellow convertor guys would be appreciated.

*** And in no way shape or form am i blaming this time on performabuilt, like i said i love the tranny and convertor and can feel the performance there, just seeing what other parts need to be upgraded to achieve the time i want***

 

Does the car have a tune to adjust the shift points. I had a 02 SS w/the same stuff you had origanally but no cut out and ran 12.61@ 110 w/ 1.91 60ft.You should be atleast mid to low 12's.And yes LCA'S & ls-6 intake would help.

 

ya the car was tuned before i got this tranny and the shift points where raised.

 

If the weather is comparible and the track prep pretty much the same. I do wonder if the trans is a quart low, something slipping if your losing that much MPH.

 

ill check that here in a little bit and then post results. I wanted to go try again tommorow. But i just cant come up with where the hell the 5mph went. do you lose a few mph up top with a stall?

 

or can my cutout being hurting me? back pressure wise?

 

Well the better your 60ft times get your mph will get less but the better your 60ft times get the better your 1/4 mile times get.

 

ya i understand that but 5mph time deduction for a 1/10 better time. I checked my tranny fluid its a tad bit low..not below the level but could prolly use half a quart. other then that im out of ideas.

 

Maybe the car has to be retuned for the new tranny & stall.I think you 60ft times should be better than 1.82 w /a 3400 stall that is not much better than i did w/a stock converter.

 

yea although i figured that since i only changed the tranny and not the computer that the old shift points should of stayed the same. Ill call norris tommorow and ask him.

 

Yes, i would call and check if that stall would change you shift points .It does'nt hurt to ask.

 

true that. Alright man thanks for you input.

 

update?

 

if you have a 3400 stall... shouldn't you be launching closer to 3400?

idk, i've never used a stall, or owned an auto car. but I thought that was the point of them.

 

I'm trying to figure out how your trap speed would lower that much..

 

It probally lowerd that much because of a different tranny,converter and lower 60ft time.

 

Yea, pretty much what you said. Frank and a few other guys think it would be a good idea to retune the car, due to the fact that the car was tuned ( and tranny shift points where raised) on stock tranny and stock torque convertor, which differs greatly in size compared to the new 9.5" convertor that is in there. But another tuner told me that obviously it cant be the covertor because 1.8 60's are pretty good and to just see if the car is running rich from the last time i tuned it, and maybe i have a bad o2 sensor ( which i do) and check my air/fuel and go from there

 

im runnin 12.4s i got a 3600 stall and also 373s. i would get it retuned.

 

ya thats what im gonna do. thanks.

 

This may not apply, but when I had my LT1 car I installed a cut out and it lowered my ET by 2 tenths. But once I removed my cats it actually started hurting my times when I left the cut out open. Thats any easy thing to to test next time your at the track