72 dart 493ci 4link car 106mm turbo,727trans with brake launching at 3800 and 10psi,4500stall,373gears,3965w driver car ran 10.39@135 with 10lb boost changed boost to 15psi went 10.29@139 engine is at 25 degrees timing locked i thought it would have picked up alot more

 

what your 60

 

Picked up 5mph and only a tenth. Obviously your making more power, but not leaving very good. What is your 60ft and 330, 660 times

 

6.60 to the 1/8 1.45-1.50 60ft

 

mph in the 1/8

 

107-108mph in 1/8

 

I wonder if your having convertor problems. The 1.45 60' is pretty good for a 10.2 pass.

 

What was the mph differences of the two psi changes? Both 1/4 and 1/8. It would help of you could post the slips. You could be pushing through the converter. What does it do when you upshift? How many rpms does it drop between shifts? How lazy does the shifts feel?

 

Id suspect converter too,4500 stall and 373 gear ,if it were me Id try around 3500 stall and a 355 gear depending on tire size..right now i have 3600 stall and a 410 gear on my set up no transbreak leaving on footbrake 0-1 lb of boost with the total of 6 psi of boost and my best sixty is 1.67 only about 200rpm drop between gears..

 

no other changes made between passes?

 

Even at 3965 I would be expecting more out of that combination!

 

What size tire? Full tub job car? If your running a 33 tall tire that rear gear is probably ok. Your converter is too loose. Your short on timing at 10 psi. Need 32-35 ( assuming it's a BBM wedge motor here) wait till 5 psi to start pulling 1 degree per psi. The car isn't hooking worth a damn for what it is. 139 mph you should damn near be or be in the 9.80's. Considering the adjustability of the 4 link you should be 60'in quicker, way quicker actually, than that. Is it setup right? What's the rest of the combo? After doing some et, mph, hp estimations, the difference between your et to hp and et to mph got bigger on the 2nd run. That tells me you aren't using the power it's making efficiently. You should be 60 footin low low 1.30's, high 1.20's there. As far as only picking up 5 mph with 5 pounds of boost, I think you got converter issues too.

 

looks like i need to address my torque converter this is from ATI ,any suggestions ?? and go though the four link again the car has 32-17.50 mt etstreet full tub car could go to 33-18.5

 

Converter needs tightened. Should have 1000-1500rpm drop on an upshift

 

:withu: Yup, thats the first place I'd be looking too. Car should be well into the 9's even at 10psi.

 

If you are building 10 psi at 3800 rpms on a 4500 rpm stall converter, you are blowing through the converter.
Its too tight. And I would try a 3800 stall if you could.

 

PTC seems to have a really good handle on converters for turbo cars. Ash runs one in his 6 second altered and pretty much swears by them. You don't need more tire. You got plenty, and the right gear to go with em. A 32 tall tire with 3.73s would almost be like having 3.55's with 28's. Yes your 4 link will probably hafta be changed around to adjust for the way it's gonna leave with a turbo. Which will probably be completely different than what it was setup for before. I know very very little about 4 links. Bout the only tidbit I've ever picked up on was that the lower bars needed to be moved so the suspension hit the tires harder because the power came on softer compared to sprayin nitrous. Your timing being too low in lower boost levels can hinder your launches too. Don't forget about addressing that at some point as well.

 

thanks for all the help guys ill give ptc a call