im running stg 2 hahn kit ~8psi..6psi that the engine sees.im testing now for leaks..,. i have the hahn FMIC, if i down grade the size of the FMIC to a smaller one wil i sse less psi of a drop? and will it hurt performace/spool time?

Originally posted by streetlightning
im running stg 2 hahn kit ~8psi..6psi that the engine sees.im testing now for leaks..,. i have the hahn FMIC, if i down grade the size of the FMIC to a smaller one wil i sse less psi of a drop? and will it hurt performace/spool time?

Someone else can probably give you a better more detailed answer, but my thoughts would be no. You would still have the longer piping associated with a fmic over a smic and probably see the same drop, I doubt if there was any difference, it would be noticeable. If you wan't to see 8psi, then spend the $15-$100 on a mbc. You can get a hallman brand new for $50, much cheaper and easier than changing your entire fmic setup, just don't get boost happy with it and you will be ok.

hhaha sounds good, thanx for the help man! i jus wanna see 7 psi til i build it.

Originally posted by streetlightning
hhaha sounds good, thanx for the help man! i jus wanna see 7 psi til i build it.

boost controller

Originally posted by eclipse982nrRST

Originally posted by streetlightning hhaha sounds good, thanx for the help man! i jus wanna see 7 psi til i build it.

boost controller

yea don't downgrade your intercooler, that's just silly.

if you want to see the full 8psi, then run a vac line from you manifold to the wastegate. right now you prolly have a like from the compressor housing to the wg, and it dont see the drop.

Originally posted by grain
if you want to see the full 8psi, then run a vac line from you manifold to the wastegate. right now you prolly have a like from the compressor housing to the wg, and it dont see the drop.

Oh yea haha, totally forgot about that! Yea that's a better way if you don't want to buy a boost controller.

hmm waste gte, i havent inspected it , but i wasnt aware there was alin on it at all its a s16g...? where would i run the line from on that?

There should be a hose that goes from your compressor to your wastegate. Plug the nipple on the compressor and tee into a vacuum line on your intake manifold and run that to your wastegate.

Originally posted by grain
if you want to see the full 8psi, then run a vac line from you manifold to the wastegate. right now you prolly have a like from the compressor housing to the wg, and it dont see the drop.

I know I've done this before, but isn't this not the best way to do this since if you develop a boost leak, you will make the turbo spin faster than it would normally have to to reach the same psi?

I would think though with only 8 psi, it wouldn't be a huge deal unless it was a big leak and this would matter moreso if you were running say 20 psi and your leak didn't like holding more than 15

Sorry to semi-hijack, but I know I've read something to the likes of this somewhere before.

Most all Turbo's are balenced to 90,000 RPM's. Thats no worse than blowing an IC pipe at full boost.

Originally posted by Star Turbo Talon
Most all Turbo's are balenced to 90,000 RPM's. Thats no worse than blowing an IC pipe at full boost.

huh, learn something new every day.

But if you have your wastegate hooked up to a port on the compressor housing and blow an intercooler pipe how would those two scenarios be equal, your turbo should still only be spooling to whatever the wastegate is set at based on the pressure coming from the compressor housing shouldn't it?

Or are you saying having your wastegate sourced from the manifold, if there was a leak it would be no worse than if you blew off a coupler when you also had the wg sourced from the manifold?

Sorry if these seem stupid, but I like to understand how things work and have now heard trustworthy people argue for both sides. (my original statement came from a comment a mod on tuners made to me)

Well think of it in two scenario's.

If your wastegate is sourced off the compressor and your boosting 10 psi. You blow an IC hose and the pressure of the Compressor will drop fast to roughly 1 psi due to vein pressure. The wastegate slamms shut and turbo RPM's will climb for that moment. That rate of climb is not gradual at all as I am sure you know.

If your wastegate-manifold and you have a leak. At 10psi your loosing say 4psi and the turbo is steadily boosting more to achieve the 10psi setting. Now keep in mind the turbo is still regulated and changes are still within the curve of the wastegate only you turbo is working to produce 15psi and your seeing 10psi.

Which one is worse? I rapid acceleration with no limits but the turbo's ability to spin freely or the turbo working an estimated 30% harder to make up for a boost leak.

I would say both are equal in different ways. Many people would argue the first is much more catastrophic and I can agree. The flip side is prolonged useage with a boost leak will make the turbo work harder and maybe expedite wear. I can agree with that too if the boost leak is really bad. Most of the Star turbo's or Hahn turbo's can produce 20psi safely (in terms of bearing wear). If your runnning 30psi and you have a boost leak then the turbo might have to work at 35-38psi to keep up. The higher pressure you have, will yield a higher leak and increased possability of a blown coupling. Your chances of catching a boost leak without trying is slightly greater.

Terry

could it be boggin down due to exhaust? i have the han half-a-down pipe then its stock all the way with a aftermarker muffler.. could that be another reason it boggs?