what psi are you guys running in your bags on the street? just put on bigger tires

[Amelio]

Well I typically run around 10-12 psi in mine......yesterday I just mounted up a set of Mickey T drag radials 275/60/15 this was stepping up from a worn out set of 275/50/15 Nitto drag radials.

The difference bewteen the two sizes is just a bit over 2" taller with the new tires....I really dig how they look

I did have to really pump up my bags to get them to clear the inner fender I am running 35psi in the driver side and 25 in the pass. I noticed the car felt a lil better and more stable and did not ride as hard as I thought it would. I have not and do not want to cut the inner fender for clearence......

Who else is running a 28" tire on the street and what have you done for clearence?

 

[L8TRH8R]

Roll the inners for clearance...

 

[oldsracer]

Do not cut the fenders!!! It was done to mine before I bought it and looks like hell, plus the inner wheel well and quarter are attached near the edge of the lip so if you cut it out you will have to rewled the entire lip. Rolling the lip is your best option and isnt hard at all when you use the tool.

 

[SCOOBY DOO]

If you use a rim with a 4" backspace like I do...then you can use the 275/60/15 DR...and it clears the wheel lip and frame with ease.

 

[captflash]

I rolled the lip and I run about 20lbs in both bags on the street. Running 275/15/60s Mickey Thompson et street. No rub even with 2-3 people in the back seat.

 

[fast86gn]

Well I typically run around 10-12 psi in mine......yesterday I just mounted up a set of Mickey T drag radials 275/60/15 this was stepping up from a worn out set of 275/50/15 Nitto drag radials.

The difference bewteen the two sizes is just a bit over 2" taller with the new tires....I really dig how they look

I did have to really pump up my bags to get them to clear the inner fender I am running 35psi in the driver side and 25 in the pass. I noticed the car felt a lil better and more stable and did not ride as hard as I thought it would. I have not and do not want to cut the inner fender for clearence......

Who else is running a 28" tire on the street and what have you done for clearence?

Wow that is a lot of psi, I have ran DR's 275/60's on the street with no rubbing issues. I only run 10-15 on the right side and 5lbs on the left. Are you running stock rims?

 

[Amelio]

No i do not want to cut the inner fenders....I had another GN years ago and that was done and I dont want to on this car. Rolling the inner lip sounds like the way to go.....

What tool is used for this? Is it a specific tool for this job I have never seen it?

I am not on stock wheels they are 8.5" Convo pro's with 3 1/4 back spacing I believe.

The other issue being is that the rear on this car and most does not sit in the center of the car so one tire sticks out a lil further than the other....changint he back spacing on the wheel may or may not help.

 

[oldsracer]

If you search in the parts for sale section for lip roller their is a kit thats floating around that you can rent. If you cant find it let me know and Ill link it on here.

 

[Chuck Leeper]

Body off location, or is the rear end out of place?

 

[SloGN]

Why does any one really need the 275


I use the 255 and have no issues and it hooks like Hell on and off the track

 

[GNcollectables]

If you search in the parts for sale section for lip roller their is a kit thats floating around that you can rent. If you cant find it let me know and Ill link it on here.

heres the link to the lip roller kit for rent:

http://www.turbobuick.com/forums/threads/eastwood-fender-roller-for-rent.198366/

 

[robzombie]

I use the 255 and have no issues and it hooks like Hell on and off the track

What's the secret, I can't hook with 295's on the street launching at 3/5lbs. of boost without going up in smoke.

 

[SloGN]

What's the secret, I can't hook with 295's on the street launching at 3/5lbs. of boost without going up in smoke.

My suspension consists of boxed upper and lower control arms moog cargo coil springs kyb shocks Hr parts rear sway bar with no front sway bar .

The best thing i ever did was remove the pinion snubber as the car was bouncing off of it on the launches.


Now i don't try to launch in the street like i do at the track. But from a stop and smack it hooks great.


BTW i 60ft in the 1.44-1.45 on the T-brake and got a 1.50 off the foot brake just the other day!



I noticed you have a ATR rear sway bar. I'm betting that bar don't fit corecctly and it's got the rear lower control arms in a bind!

 

[robzombie]

I noticed you have a ATR rear sway bar. I'm betting that bar don't fit corecctly and it's got the rear lower control arms in a bind

Why would you think that??

Now i don't try to launch in the street like i do at the track. But from a stop and smack it hooks great.

I don't have a problem either if I don't boost on the launch, because it takes time to build boost, at 18lbs. and first to second shift on alky it will blow the tires over also so it's a problem for me on the street even with the tires I have.

I do have the front bar on and know that I'm hurting my launch,also don't have 90/10s it is mostly a street car and I like it to handle.

I know it can do better just trying to find out how.

 

[SloGN]

Why would you think that??



I don't have a problem either if I don't boost on the launch, because it takes time to build boost, at 18lbs. and first to second shift on alky it will blow the tires over also so it's a problem for me on the street even with the tires I have.

I do have the front bar on and know that I'm hurting my launch,also don't have 90/10s it is mostly a street car and I like it to handle.

I know it can do better just trying to find out how.

every ATR bar i have messed with the bar don't slide into the control arms like the stock one does. most of them you have to hammer the bar into place and that in turn makes the control arms want to bow outward and thus binds the bushing by side loading them.

Richard clark even made a jig to machine the atr bars by so they fit correctly with binding the rear arms. ( i'll try and snap a pic of it and a non machined bar to note the fitment issues)


I don't have the 90/10 drag shocks either. my car is a street car and i drive it alot. You also have the adj control arms how are they set? you should start with them at the same length as the stock ones are.



If i bring my car up to 0 vac and smack it the tires hook with just a tad bit of spin and don't have a problem after that. Now i usally run about 28 psi in my tires. And i also run around 16-17 psi in the street as the car is just too dang fast with more boost note i have a ball bearing turbo that spools fast. At 16-17 psi the car runs 7.10 @ 98mph in the 1/8 so it's moving out.

 

[robzombie]

My lower bars are tubular with adjustable hiem joints.

You also have the adj control arms how are they set? you should start with them at the same length as the stock ones are.

I will have to find out what the stock length is and I'll go from there, I know I need to tune it as i've been fine tuning the engine setup since I bought the car, It's fun and a PITA at the same time, but I know you only get ouy of something that you put into it.

i'll try and snap a pic of it and a non machined bar to note the fitment issues)

That might help me as well as others with the same problem.

Thanks Rob

 

[Amelio]

If you search in the parts for sale section for lip roller their is a kit thats floating around that you can rent. If you cant find it let me know and Ill link it on here.

Thanks for the link I will hit him up....thats a great idea!

 

[Amelio]

Body off location, or is the rear end out of place?

I am not sure if its the body or the rear end but the other two GN's I had.....had the same issue. Its not much maybe 1/2"-1" my guess is it was not perfectly centerd from the factory.

 

[Amelio]

Why does any one really need the 275


I use the 255 and have no issues and it hooks like Hell on and off the track

well for one reason is I really like the bigger tire look very beefy. secondly is the biggest reason is traction.

this is mostly a street car but I have good stuff under it......90/10 shocks up front 50/50 in the rear eibach springs southside upper and lower control arms and air bags....no sway bar up fron and stock one out back and urethane bushings.

I have been running a 275/50/15 for the longest time but I really like the look of a 28" tire. I just put these on saturday and I went to see how well they work.....zero vac on the stall the car will roll out and hook but once at the top of first and my converter hits its all over it got loose and then hit second and continued to get outta shape so I lifted.

I can not even imagine a 255 series tire working????? I only run 28psi in the tire and I just came back from a 45 mile drive so they had heat in them even before I tried launching it they were picking up rocks and stuff. Now it could be that the rear is stiff because the airbags are pumped up but I had the same result with the 275/50 tire to although it twisted the tires much sooner and I think that is due to the gearing advantage because they are 2" shorter.

Maybe there is something I am missing in my suspension setup but there is no way I could hook with anything smaller????? I am not even running much boost either 19-17psi thats it....I would like to run a lil more but I would need to hook better first.

Suggestions on my suspension........

 

[SloGN]

Having the air bags pumped up is hurting it. If the car can't squat some then the weight transfer can't happen. Even when adding a taller tire make the rear end even higher to start to get the rear to squat to help get the front end up.

I'm not a suspension guy at all I'm just stating what I have found on my car . And what I have tried.