Uneven boost levels

[williamtroutman]

I purchased a 1990 talon 3 days ago. It is my first DSM and also my first turbo. The boost was set to 14psi before I purchased the car. I am finding that I am producing very little boost in 1st gear (4-5 psi), 8-10psi in second, 10-12 psi in third, 12-14 psi in fourth, and spiking to 17 psi in fifth. Is this common, if not, what to check for? Any help would be apreciated.

 

[hubz91talontsi]

1st Gear sounds correct. Boost is the amount oh air the turbo is sucking. Obviously if your only doing 20-30 ## not getting a big amount. Spiking on the other hand you do not want that. The car is stock? You may not want it spiking to 17 =X. To answer your spiking question you will need someone else that has spiked. =)

 

[Boost92awd]

Looking at your profile it looks like your spiking problem is do to having a full exhaust. Look into getting a ported manifold and a ported o2 housing this should take car of that problem.

 

[Black95awd]

Looking at your profile it looks like your spiking problem is do to having a full exhaust. Look into getting a ported manifold and a ported o2 housing this should take car of that problem.

and a larger WG flapper or external gate.....

 

[turboglenn]

What size turbo is on it? On larger turbos it's normal to not make your full boost in first or second gear because the motor isn't loaded down enough to fully spool the turbo. But unless you're running a large t3/4 or simimlar this shouldn't be an issue. I can make the full 18psi in first and second, but the tires are roasting so hard that it barely reaches full boost by redline in first. This is on a T3/4 hybrid 57 trim with stage III turbine wheel

The spiking is probably that you're running something like a 16g or similar and it's not getting anough exhaust around the turbine with the WG flapper open causing the turbo to spike or creep at times when the motor is fully loaded down. It could be anything from a unported WG are and O2 housing, or even a crappy MBC can cause spiking in many cases

 

[the1cov]

Are you getting this boost with the peddle floored, Is the car studdering like it is cutting out? Or is it smooth just not the right amount of boost.

 

[Boost92awd]

Might want to do a boost leak also.

 

[DJYoshaBYD]

^^^^ boost leak test... its just good to do

yes.. you are spiking because of your full exhaust, and like this other cat said, your motor wont make that boost in first most of the time because of the load on the motor...

is it tuned? is your BOV venting (just asking).. alot of people who have dsm's who dont associate with other dsmers dont know what the hell they are doing... you need to make sure you have all the supporting mods that you need to make boost at that high...

help us help you.. post what you have in the car in detail... pics help too, if you dont know what you have...

 

[williamtroutman]

I can get pics this afternoon of what I have. I am not very familiar with DSM's as this is my first. The BOV is venting at around 4psi in 1st. It is almost like it lets go without me letting off. Like I said, I bought it a few days ago and for dirt. The original engine and tranny were blown and swapped. I will have to get the model number off the turbo. The turbo is a 16g evo III

 

[skeeter4200]

you should look at getting a 2g manifold and o2 housing and have them ported

 

[williamtroutman]

Has anyone come across a neuspeed motor in a talon...it may just be the cam gear cover... seems kind of odd to me. I mean, for what I paid, I don't really care. It just seems odd. 2.0l 16v DOHC