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turbo-baron
09-29-2007, 09:39 PM
So a buddy of mine who has helped work on my car for quite some time has just cought the TM bug. He is looking at picking up a 1990 baron VNT vert. Super clean car. My question is what mods can be done to these i havn't read up on them due to the fact my car is a TI. What should he be doing to it?

Thanks in advance
Brendan

Directconnection
09-30-2007, 12:48 AM
Different than other turbo vehicles.

Don'[t go crazy on the exhaust as it will go into overboost shutdown. Get a re-calibrated computer (make sure it is one that is known to really perform...some out there suck)

Head work and exhaust manifold work will help as usual and balance shaft removal, too.

glhs875
09-30-2007, 08:47 AM
I would look into porting out the exhaust mani, and then install an external wastegate on the mani while it is off, so the exhaust system can then be really opened up and still be able control the max boost. And also a better intercooler will also help. These 3 mods can make a large gain. I have more ideas for my 90 Shadow C/S VNT, but there top secret! :D

turbo-baron
09-30-2007, 10:37 AM
Thanks guys. Well the less mods there are to do the less chance there is of him beating me lol. Are the VNT intercoolers the same as the TII's?

Directconnection
09-30-2007, 12:59 PM
Thanks guys. Well the less mods there are to do the less chance there is of him beating me lol. Are the VNT intercoolers the same as the TII's?


No, the VNT cooler cools better but at the expense of flowing alot less. T-II is better.

turbo-baron
09-30-2007, 01:59 PM
Will a TII I/C bolt up to the VNT rad inplace of the VNT I/C?

tryingbe
09-30-2007, 03:33 PM
Replace the VNT turbo with at least a TII garrett will net you more power per boost.

turbo-baron
09-30-2007, 03:46 PM
Replace the VNT turbo with at least a TII garrett will net you more power per boost.

No lol. My buddy is buying the car. I can't have him beating my baron lol. When it comes out of my garage it's going to have. 555 phantom grip LSD,TII rad/IC,12-14psi, Suspention techniques lowering springs,kyb gr2 struts:thumb:

JDAWG
10-01-2007, 09:04 AM
after fighting with my 90 tona vnt for a year to keep it stock the best mod I can suggest is to rip that f-ing turbo off the car

turbo-baron
10-01-2007, 12:18 PM
Alright thanks guys. Once i pick up my 300+hp motor for my car ill give him my garret lol.

t3rse
10-01-2007, 12:40 PM
Replace the VNT turbo with at least a TII garrett will net you more power per boost.

first thing i'd do. i gave my buddy with an 89 csx my old t2 which we just put on there. not running yet, but i'll let you know how it is...

tryingbe
10-01-2007, 01:38 PM
No lol. My buddy is buying the car. I can't have him beating my baron lol. When it comes out of my garage it's going to have. 555 phantom grip LSD,TII rad/IC,12-14psi, Suspention techniques lowering springs,kyb gr2 struts:thumb:

GR2 struts are trash for a heavy car like the LeBraon. I know, I have a set on my Daytona Shelby. Made the car floaty like a boat. I always running 15psi in my Daytona Shelby, it was ok, but it wasn't that fast.

turbo-baron
10-01-2007, 10:40 PM
I got the struts and spring for $75 so im putting them in lol. My stock ones are completley shot. Right side sits lower then left and if i bounce the front of the car with one hand it will go up and down about 5 times. Im probably dropping in a TII garret aswell

quantum
10-05-2007, 12:35 PM
The best mod I ever did to my VNT was to remove the line from the top vane actuator nipple and plug it, then replace it with a line coming off the turbo pressure side (the closer to the turbo outlet the better) through a granger valve set to the max psi I wanted. That way the computer still controls the vacuum side, but when you get into boost the granger reacts faster to the pressure change than the computer does (I'm guessing this is due to the time it takes for the pressure to reach the map, the computer to react, fire the solenoids, and the pressure to travel to the vane actuator from the solenoids). Doing this solved my over boost issues even with a bigger exhaust.

glhs875
10-06-2007, 09:06 AM
The best mod I ever did to my VNT was to remove the line from the top vane actuator nipple and plug it, then replace it with a line coming off the turbo pressure side (the closer to the turbo outlet the better) through a granger valve set to the max psi I wanted. That way the computer still controls the vacuum side of the, but when you get into boost the granger reacts faster to the pressure change than the computer does (I'm guessing this is due to the time it takes for the pressure to reach the map, the computer to react, fire the solenoids, and the pressure to travel to the vane actuator from the solenoids). Doing this solved my over boost issues even with a bigger exhaust.

Do you still have a converter (cat) on the car? What size exhaust? What's your max boost? Sorry for all the questions, I'm curious!

quantum
10-06-2007, 11:50 AM
Do you still have a converter (cat) on the car? What size exhaust? What's your max boost? Sorry for all the questions, I'm curious!

Exhaust was 2.25" with a cat. Set max boot to ~13.5 psi, before it would spike past 14 and hit overboost shutdown.

glhs875
10-07-2007, 09:04 AM
Exhaust was 2.25" with a cat. Set max boot to ~13.5 psi, before it would spike past 14 and hit overboost shutdown.


I was hoping you were running like a 3" exhaust without a cat, and still able to control the boost. I have a feeling an added external wastegate will be needed for the above. My exhaust is probably larger than yours already (2.5") and with no muffler only a cat. I would like to step up to a 3" with no cat and a muffler instead.

quantum
10-07-2007, 01:53 PM
I was hoping you were running like a 3" exhaust without a cat, and still able to control the boost. I have a feeling an added external wastegate will be needed for the above. My exhaust is probably larger than yours already (2.5") and with no muffler only a cat. I would like to step up to a 3" with no cat and a muffler instead.

I'd be interested to see if it works for your setup as well. If your willing you can still give it a try for the effort of rearranging a few vacuume lines (assuming you already have a g-valve) and if it doesn't work you only lost 30min of time.

Directconnection
10-07-2007, 10:31 PM
I ran a catless 3" mandrel system with ultraflow on my other VNT. The custom cal I had made it tolerable but still overboosted to about 17psi in 4th and 5th.