hey this weekend i was driving down a long stretch of highway and decided to downshift and give it hell. Well I downshifted into third, then into fourth. Once in fourth i looked up at my boost gauge and it said 18psi!!! Now what sucks about this is that I am supposed to be at 9psi. It has been creepin lately up to about 10 or 11, but 18! that is double what im suppose to be running. Not to mention the internals are completely stock. i have a couple questions about this...

1. Could the gauge be faulty? Its an autometer pro comp gauge. is there a certain place i might want to tap the vacuum source to, to get the most accurate reading? or is the gauge just screwed up.


2. Could something be wrong with the wastegate? Its a Tial i dont know for sure what size it is off hand...i could find out if the size matters. could i need a new 9psi spring?

any help on this would be greatly appreciated. It was already making me annoyed with the boost creep, but 18psi is rediculous and i really dont need my motor goin out on me right now.

Thanks
adam

 

the cold weather is most likely causing your creep, everyone has been having problems, what manifold are you running?

 

boost always creeps when it is cold. My dad's talon goes to like 22 then down to like 18. We know why, but it just happens.

 

I have the OBX Stainless manifold. I understand cold weather may be causing some creep, but to have cold weather be the reason for doubling my boost seems a bit unrealistic.
The reason i mentioned maybe my gauge is reading wrong is because, at double the amount of boost, i felt no difference in how fast the car was... you would think id be able to tell a difference from 9 top 18 psi. also id think the motor would hit a fuel cut-off or just plain blow since its not tuned for fuel to 18psi.

 

by obx do you mean ssac style? if so, the combination of poor wg placement with poor flow along with the cold weather is probably overwhelimng the wg. the motor shouldnt hit a fuel cutoff just from boost unless you have some sort of boost cut established with your engine management.

if you have access to another boost gauge, by all means try it. it could be your gauge, it could just be cold weather.

 

what kind of gauge do you have?

i have an autometer and when i dynoed my car it said 18psi but the MAP said it was only 13psi so that is some thing to conisder about auto meter but i dont know good luck

 

yes my OBX looks like the SSAC manifold. i wouldnt have chose that one on my own but the shop that did the install said it was a good choice

my boost gauge is an autometer

im going to give the shop that installed it to see if they have any ideas tomarrow...

so if they come up with no ideas, and i can get another boost gauge to rule that out as an issue, am i going to just have to break down and get a different, better, manifold?

 

well, the ssac style mani will make the boost creep from cold weather worse, did you experience any creep before it got cold?

 

not to my knowledge...this problem was first brought to my attention by my friend who was ridin with me in the car on the ohio turnpike and i did a long pull...he's like dude ur readin about 11psi. this was about fall at night when weather started getting into the 40's.

im not so much concerned about the small creep 2-3psi, but im just completely stumped as to why i was reading 18PSI when im only supposed to have 9. i just cant image what would cause my boost pressure to double, unless the gauge just wasnt reading correctly....and like i said before, i felt no difference in how fast the car was, still felt like the 9psi range to me...certainly not doube that!

 

i'd say try a new gauge and get back to us.

 

alrighty, ill do that and let u know what happens...thanks for all the help

 

i havent had a chance to try a different gauge in my car yet...but i had an idea that might get the problem corrected for relativley little cost...

would getting like a 5psi wastegate spring then a boost controller to slowly up the boost to where it should be...basically see how high it wants to creep up from 5. if it doesnt creep to bad then i can just turn up the boost with the controller...do u think a lower psi spring could be an option?

 

anyone think this idea is worth a try?