Preliminary Dyno tune, low boost

[DrDane]

Ok so finally pieced together my car. Paxton torque booster (3.33 pulley), with Holley sniper, opg/cg, catless long tubes, to MBRP race 3", Sai li fuel system, with ID 1000's. Car doesn't seem to be boosting how we'd expect, its only making like 8.5 lbs at~7300 and making 635 rwhp at that time with 15 degrees on test tune, swore I had the hyper gate sprung to be 13-14 lbs, anticipated more in the 770-800 range at 7xxx on e85.
Tried tightening the belt, no help, t bolts seem good, must be the gate opening early?

Are my expectations that far off? Any other thoughts on what it could be?

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[MyLilPony]

If you have a pressure regulated air hose you can test the gate. That would be my guess as to why you are down on Boost. Or buy a boost controller

 

[dubster99]

Boost controller ftw on a gated setup for sure.

 

[Dennisn]

Boost controller ftw on a gated setup for sure.

I'd find out what your issue is before you throw a boost controller in the mix. You probably don't even need the boost controller. Check your springs in the wastegate. Make sure they are the correct ones for the boost you want. Make sure you don't have any boost leaks also.

 

[Dennisn]

Just noticed your running a sniper. Seem to remember someone had an issue with one leaking?

 

[smokinzx14r]

Ok so finally pieced together my car. Paxton torque booster (3.33 pulley), with Holley sniper, opg/cg, catless long tubes, to MBRP race 3", Sai li fuel system, with ID 1000's. Car doesn't seem to be boosting how we'd expect, its only making like 8.5 lbs at~7300 and making 635 rwhp at that time with 15 degrees on test tune, swore I had the hyper gate sprung to be 13-14 lbs, anticipated more in the 770-800 range at 7xxx on e85.
Tried tightening the belt, no help, t bolts seem good, must be the gate opening early?

Are my expectations that far off? Any other thoughts on what it could be?

I do a lot of turbo bikes and we use the same gate .. The spring comes listed at a PSI rating but rarely do we see the PSI they are rated at .. We used a nine pound spring and would only see 6 or 7 PSI .. We have had it go the other way also , install a 6 psi spring and make 9 psi ..Each system is a bit different so you may have to try a few different springs to hit the number you want ..

 

[dubster99]

I'd find out what your issue is before you throw a boost controller in the mix. You probably don't even need the boost controller. Check your springs in the wastegate. Make sure they are the correct ones for the boost you want. Make sure you don't have any boost leaks also.

I didn't mean before he figures out the issue. But a boost controller on a gated setup is definitely the way to go.

 

[DrDane]

Thanks guy will take the springs over there tomorrow, anyone want to guess final numbers on e85?

 

[DrDane]

Still 15 degrees timing, still having lost boost, Maxflow BOV is hooked direct to vacuum on sniper, and springs in hypergate (5+7) still peaking 8.5lbs, now making 679 whp ....im happier but feel like this could have been with stock manifold, no headers, no intake etc.

 

[Dennisn]

Sounds like either a boost leak or your springs are off.

I'm assuming you have the correct pulley.

 

[DrDane]

Sounds like either a boost leak or your springs are off.

I'm assuming you have the correct pulley.

It had the 3.6 on the headunit, which even if it wasn't swapped would have made more than 8.5, but it should have the 3.33 on it now, but I have not seen since its been strapped to the dyne.

 

[DrDane]

OK update, curious if any other ideas, no vacuum issues, no belt slip. 3.33 pulley. Swapped springs supposedly has the 6 and 10 (16) in the gate but only making 12.5lbs on ~20 degrees timing. Putting out 747rwhp at 6350 and 660ftlb at 5500 on a Dynamite dyno (which also seems like a really low peak for a coyote/sniper/header combo).

So it seems to be healthy, but less boost and power than I wanted mores frustrated why it seems to open hyper gate 20% under what the springs are at consistently, and why it peaks early, earlier than I'd expect with stock intake?

Thoughts? Try a different tuner :( ?

 

[Reds197]

Did you pull it to 7500 and it peaks at 6350? There is another 70 horse in RPM. If it peaks at 6350 the gate is opening to early.

 

[DrDane]

Did you pull it to 7500 and it peaks at 6350? There is another 70 horse in RPM. If it peaks at 6350 the gate is opening to early.

https://ibb.co/moGfta

They stopped just around 7000, because it wasn't doing anything anymore. I looked at the mechanical boost gauge and its a smooth linear boost builder, just seems like: 1) the gate is opening too soon, 2)unclear why it doesn't like more revs

Since 13 lbs of springs yielded 11 lbs of boost and 16 lbs of springs yielded 12.5ish, Im damn tempted to put the 10 and 11 springs in to try and get 16-17lbs and get a glory run....

 

[Kahboom]

Do it, do the glory run. Good numbers though on 12.5lbs of boost.

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