97 12v compounds building too much boost

meatball

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Joined
Nov 6, 2011
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626
I normally try and exhaust all options before posting on here , but this has me stumped.
ill lay out my set up first and explain my issue second.

-63/68/12 gated over a box s480.
- spring gate from stainless diesel
-ddp stage 4 injectors
- timing at 22*
- pump is a 215 bought off a comp member that shipped it directly to kevin for me . its maxed and balanced flows 650cc plate full forward , 300cc full back. with 024 dvs and 4ks . I've had the pump about 3yrs now. it has a gov spring in the afc from seth set at 40 psi full fuel , using regulated shop air.
-supply is an airdog I forget what with a torktek 60 ofv
- cam is stock
-bottom end stock
- heads been oringed with 425's
no fuel press gauge , no drive press gauge

I've never been past 3/4 throttle with the truck and this 913 (only when it was a single 62 and that was pointless) , its always been to much.
rolling into it in 3rd, it'll light . ill see 60psi total 30 psi primary ...touch more throttle ..70 / 35 ...80 / 35 .... 90 / 35-40 .... 100psi i'm around 3/4 throttle and let out ... i'm not sure how far it'll go i'm not brave enough or rich enough to try It . when lit it clears the smoke very well.
I need to strap all the I/C piping together because I blow them apart. all bead rolled all tbolt clamped blows the boot right out of the bite .
the plate is back to a little less than half travel , housing too , zero preboost . throttle is very sensitive .

a good friend is running a 62 over 475 , ddp4+ , manning cam, and a maxxed 180 pump ,plate forward at 500cc , westons 7mm dv's. it'll hold 70 psi full throttle with 30psi primary . hardly any smoke . springs are 4ks and the throttle is way less touchy .

I let him drive my truck today and he had a hard time mines so touchy.

i want to think my ratio is pretty good , my cruise egt is 6-700 .. im sure i could benefit from some tuning but it drives pretty well and spools quick imo.
it has power .

i just don't hear or read of many people building that much boost with this size compounds . any thoughts or similar circumstances ?
 
Check your spring gate. When mine was tightened down to not open, I could hit 100psi. Backed it off from full closed about 8-10 times and now see 70 psi max.

I don't have a guage on the primary.
 
I've tried about two threads from undone . I'll give it another shot . I was way tight on the gate when I first put them on . Ratio was way out of whack . Where I'm at now it seems they're sharing the work pretty well but it keeps on going .
I ordered my gate from cpp and only received one spring my friend ordered through stainless and received a long and a short spring . He's running the short maybe I should look into getting that spring .
 
Definitely need to figure out if the wastegate is opening correctly. Seems to me that it may be opening just a little but not enough to control turbine speed in the higher rpms.

I'm running a 64/71/14 over a s480 and see around 80-83 psi. I think my wastegate still needs to open a little sooner as well.


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Mine did the same thing on my old setup, i would hit 98psi at wot. Im still using the same twins but im seeing 84psi max now
 
Give it a test run with the wastegate loose, flapping in the wind so to speak and see where boost peaks. It'll obviously be smoky and slow spooling on the bottom end but it should give you a chance to see how it runs with 45-50 psi from the S480 and just 80-85 total.
 
I'll give that a shot and post it on here , thanks blue
The spring came in from stainless , its a good bit shorter and I only have about six turns of adjustability now . I went and got a shorter bolt for it so I can play with it more before I run out of thread .
 
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