flangemastermike

have a problem holding boost. im using a .57 trim t3/t4 (.50 compressor/.63 exhuast) which i think should be good enough to flow 10 - 15 psi without goin out of its efficiancy.
i had a mbc set at 8 psi and it held until 6500 - 7000 where its starts to slowly come down .
i got rid of the mbc to see if it was that , using 3.6 psi spring it still kinda drops but not as much maybe to 2 psi. can hold high boost until high rpm so i dont think its a boost leak ,. any one got any ideas or experianced this ?. im stumped

Westrock2000

Well we definently need to know what motor this is to get an idea of "PSI".

But for reference I have a Turbonetics T3/T04 50 Trim on my SRT and running 17 PSI and I'm barely into the "sweet spot" of this turbo. Turbo should be good for 400-450HP. Now if you have a good K-Series, then ya 15 PSI might be moving alot of CFM, but if its a D-Series then it shouldn't be as big a problem.

coneheadsracing

exhaust setup too please.

flangemastermike

setup is as follows

b16a2 with b18c4 pistons (had a little accident tuning) 9:1 cr
pfabrications log manifold
xs power 38mm wastegate
greddy S BOV
T3/t4 .57 (.50 compressor/.63exhuast)
home made 3" downpipe and full 3" exhuast

y7turbo

where is the wastegate soarce line hooked up to? i had that problem on my setup when i had the line going to the compressor housing. i changed it to the intake manifold and it held solid all the way to redline.

da_dude

Change the spring to a tial spring.

Schister66

i'd bet its the Chinese wastegate....




Modified by Schister66 at 3:45 PM 2/6/2007

vtec.dc2

what type/size/brand air filter do you run??

civicjdmb16a

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Schister66 &raquo;</TD></TR><TR><TD CLASS="quote">i'd bet its the Chinese wastegate....


Modified by Schister66 at 3:45 PM 2/6/2007</TD></TR></TABLE><TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turb20_vtec &raquo;</TD></TR><TR><TD CLASS="quote">Change the spring to a tial spring.</TD></TR></TABLE>

flangemastermike

wastegate vaccum is off the inlet manifold. but the BOV is also T'd off the line. air filter is a fine metal mesh with foam over the top as its kinda tight for space , works well. think u might be right about the "made in a cave" wastegate. think a tial is gettin purchased soon.

da_dude

I have used an ebay tial style wastegate with a tial spring with no problem. That was in my old setup when I had it on my hatchback.