I did an sr swap over winter, tried to keep it stock with stock intercooler and just a hks bov. and the t25 had a few nicks in the intake side of the turbo. I had a brand new auto metre gauge and I was only able to get 5psi. Well I just got a t28 from a friend and it still feels the exact same and only gets 5psi, and it was mad quick in his car and got 7psi?
Any suggestions?
Half way through reading I woulda said the wastegate spring is no good. But I guess that’s not the issue.
If it’s dumping at 5psi, could be some of your vaccum lines were run improperly. Check the ones leading from the turbo/wastegate, and ones leading to the BOV.
Sounds like your bov is leaking and your only able to build 5 psi. If it isnt, then you must have a large leak somewhere.
Double and triple check for leaks and broken/cracked vac lines.
You either have a major boost leak or the boost gauge is messed up. Try borrowing another boost gauge.
Gona go with the first 2 replys,
Had the EXACT same issue described here,
Stock sidemount, Stock SR, AVCR only read 5psi, Swapped turbos same issue, Checked my whole system for boost leaks and it held upto 15psi no problem. Ended up being the presure line to the factory Recerc valve was pinched and wasnt working, Replaced it with a new line and got bang on 7psi all day long. for about 3 months till the recerc valve messed up, replaced that with a Greddy Type S and havent had a problem since.
The factory S13 intercooler has 3 sections that run to the factory recerculation Valve,
if 1 looks ok and is hooked up to a good Vac\boost source then 3 is probably where ur issue is, probably cracked or busted, I also have a factory recer valve that i know works and holds atleast 10psi if you wanted to barrow that for a test if the rest is all ok.
I will make sure to check all those lines, but if it was a vacuum line wouldn’t my car act a little weird? I get perfect idle and car runs good other than it feels a little sluggish, especially after feeling how quick his car picked up with this turbo.
And I have one if the little lines teed off that comes off the stock ic, believe it was for the stock bov.
well even if the lines are fine the recerculation valve could be messed up as well. In which case you would have the same issue, those things only hold 5psi when they mess up or with no presure to keep them closed from the vac\presure system. Im assuming it hold 5psi solid, im also assuming that the remainder of the system is hooked up correctly. but what you are describing is exactly to the letter what happend with my car. When you really push it then let off fast do you get waist gate flutter?
Hard to tell if my wastegate is fluttering, all I hear is the hks bov. I’m gunna try taking the stock recirculation valve out and block off the lines. Will that work since I eliminate it?
sure, i ran a greddy Type S with the factory side mount, and blocked off the opening on the sidemount, ran 10psi on that for a week or so ran fine.
All fixed! I just took out the stock bov and blocked off the tubes. Now getting 7psi, and defenitly feels better. Thanks for all the help and input.
good to hear , have fun with your new found power
farmer
Lol turbo blew already, good thing I got it from a buddie and there is no charge. Just get the fun of doing it all over again.
Anyone know how much it would be to rebuild a t28?
Not worth it prolly 600+ just buy a new turbo