StreetStangs.net

StreetStangs.net (http://www.streetstangs.net/forumindex.php)
-   Mod Motor Tech (4.6 & 5.4) (http://www.streetstangs.net/forumdisplay.php?f=18)
-   -   1st full pass in the car 1/8th mile! (http://www.streetstangs.net/showthread.php?t=15374)

TurboPete 11-20-2009 11:24 PM

1st full pass in the car 1/8th mile!
 
Well Ive been slowly getting things ready on my car , the tune up is good and Ive got my new Drag Radials on the car , so I went to Immokolee out here in Florida to do some test runs.
My 1st run was just to see how much boost I could leave with on the street tune 14.5 psi's , and Transbrake. Got up to the line hit TB and could only get 5 psi's , 60ft was 1.83 leaving around 3100 rpm's . Only went thru 1st and 2nd gear and let out.
2nd run turned the boost up to 19 but it would still only leave on 5 psi's . Car didn't shift into 3rd because of my shifter problems NOT TRANSMISSION.
So I figured what the hell might as well make a full 1/8th mile pass , so I stayed in it all the way down and was able to shift it into third , went a
7.13 @ 106.45 on 19 psi's and leaving at 5 psi's , 60ft was a 1.91 .

Cant believe she went 106.45 in the 1/8th with a bad 60ft .

I have a smaller a/r .81 which Im begining to think may help the spool up , but there's also sending the converter out to loosen to 3400 .
Im sure that will help boost come up faster and maybe get 8 to 10 psi's off the line.
What do you guys out there think , do you have similar set ups and what would you do or have done to help the car leave harder.

Pete

rtusnake 11-21-2009 01:08 AM

Great mph for sure. I know some guys do some changes in the timing down low to build boost. How bad is the car bogging?

SlowJoe 11-21-2009 05:24 AM

Got to love these mod motors! Good pass

TurboPete 11-21-2009 06:27 AM

Quote:

Originally Posted by rtusnake (Post 194349)
Great mph for sure. I know some guys do some changes in the timing down low to build boost. How bad is the car bogging?

I have a real good tune the timing is fine , my issue is that I run a Big 78mm with a .96 rear housing , the car pulls crisp and clean from the beginning . It doesnt bogg off the line its just needs more power / boost to come out harder . My converter stalls at 3000 if I could leave at a higher RPM or maybe just more boost like 8 to 10 psi's I think it would be enough to make the 60ft drop to the 1.5s .
I run a 3.55 gear in the car with a 325/50/15 DR's.


Pete

rtusnake 11-21-2009 07:20 PM

Do you have any kind of two step on your car?

Dale McPeters 11-21-2009 07:21 PM

Pete,

Just a thought but....
You might do like Joe Lynch did on his car and add a small 50-75 shot of nitrous right off the line. He was having a problem with 1/8th mile stuff too. His 1/4 mile times were fine at around 1.39 60 and 9.9x it was the 1/8th mile that was killing him as the turbo would not come on quick enough.

Unless of course you are class racing and are limited to one power adder. :D

TurboPete 11-21-2009 08:04 PM

Quote:

Originally Posted by rtusnake (Post 194395)
Do you have any kind of two step on your car?


Yeup I have 2 of them , 1 set on the foot brake the other on the Transbrake.

http://i68.photobucket.com/albums/i2...lsystem002.jpg

http://i68.photobucket.com/albums/i2...lsystem003.jpg

The car builds boost just wont build more than 5 psi's some people tell me to loosen the converter to 3400 the extra RPM's will help spool the car faster. Im just curious even if it was building boost slowly, it should have boosted more than 5 pounds I would think. Tomorrow I will datalog the a/f on the Transbrake, and see how much timing is in it at the target rpm of 3000 to 3200. I was told by some good buddies of mine who all run Buick T-Type's that you want the a/f to be at 11.5 to 11.8 at the target RPM's for it to spool . This all sounds great but if it doesn't work Im going to spray it and be done with it.

rtusnake 11-21-2009 09:04 PM

There has to be a way to get it to spool without nitrous. Its either going to be the convertor or tune. Some guys on modfords are spooling twin 76's rather quickly

QWKSNKE 11-21-2009 10:18 PM

I could see loosening up the converter helping but it seems to me that you still should be seeing more than 5 psi at 3k rpm on the transbrake

coupe 11-21-2009 11:11 PM

I'd play with the 2step settings... what will it get to on the footbrake? And what is the 2step at on transbrake? I'd raise it and see what it does. Are you on the floor when transbrake is on?

A 78mm turbocharger should mph a good bit more than 106 at 19psi. Something is just not working like it needs to. I'd like to see a datalog.


All times are GMT -6. The time now is 12:09 AM.

Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.