SCereal

iTrader: (4)

For a build with a boost logic NA-T manifold and a Tial F 46mm wastegate with a precision 76mm turbo (.96AR) wanting to limit boost to about 8psi (10.5:1 comp, 93 pump gas) would the .5 or .6 BAR spring do the trick? I dont believe my manifold is prone to boost creep and the WG should be big enough to keep it from overboosting. (i hope, chime in if you think otherwise please) BOV will be a SSQV with all 3" ic piping and a 4" FMIC.

should i go smaller spring and a manual boost controller? would that be advantageous at all? down the road i plan on an electronic controller and all the other goodies to support a high hp build but for now just looking to stay at 8psi.

thoughts?

Ali SC3

iTrader: (10)

76mm is a large turbo and .96 is a large AR to be running such low amounts of boost but If you won't be raising the boost that much higher go with the .5 and put a manual boost controller in the line. both a .5 bar and a .6 bar are going to creep some, they are just light springs, a simple ball and spring manual boost controller will take care of that issue though and let you turn it up to 8psi if the .5 bar is a little low.
you can't go down in boost if the .6 is too high but then again you can probably run closer to 10 psi on that setup with 93 and be fine with the .6 bar so its your call really.

are you sure you don't have stock 10:1 compression. 97 is non vvti should be 10:1, but 98+ vvti is 10.5:1 compression.

SCereal

iTrader: (4)

Yes, you are correct, sorry, my chevy is 10.5:1 i get the numbers mixed up sometimes.

I'm only stuck at this low boost until the trans is built and swapped, then i'll be looking for whatever makes about 800whp on E85. I think i'll go with the .5 bar spring. I don't really care what the actual boost number is so long as its safe at each stage. can always swap it out later for a slightly higher spring when the time comes.

thanks!

Ali SC3

iTrader: (10)

no prob, yeah 8 psi should be plenty safe although I have a 61mm and not a 76mm so YMMV, I used to run 11 on stock everything for a while.
the manual boost controller is always a good idea with the lower boost number springs I have learnt from running a 8-9 psi spring myself, it creeps quite early without the boost controller in there, but putting it in spool is much better even without raising the boost.

blk&blu*j

iTrader: (1)

Not to rain on you parade but a 76 mm is not really enough turbo for 800hp through an auto without alot of other supporting mods, intake, healthy cams, 2000cc inj, fuel pumps, etc etc. Also you may want to revise your goal as the stock GE bottom end will not support 800 through an auto. hell a GTE stock bottom will not support 800 through an auto on E-85 to much torque you will bend a wrist pin way before 800 and the rods will bend like a pretzel its not the hp thats the problem its the torque E-85 makes. GL

SCereal

iTrader: (4)

Thanks for heads up, I'm aware of and planning all the supporting mods, just left it out here for brevity. I hadn't heard about the rods on e85. I'll do some more research. I had planned porting and valve mods down the road but not rods or pistons.