Needing input.. i have a 96 cobra with a built shortblock. Running a blow through setup with a treadstone tr1245 intercooler and an 8 rib setup with reichard racing tensioner. Have a 7.5” crank pulley and a 3.15” supercharger pulley.. only seeing 15lbs. Of boost through a v1-ti.. does this sound normal? Seems to be no boost/vacuum leaks or belt slippage.. according to vortech ss calculator i am already over spinning it. Any input is appreciated.
Vortech Ti trim boost with 3.15 pulley
- Thread starter MOmystic
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I believe there is roughly 10% slippage no matter what that throws those calculators off.
On my sbf TI I spin 65k rpm at shifts for years. I do have the race bearings.
I’ve seen as high as 21lbs plus
Yours seems inline for how your spinning it, renegade cars would spin well into the 70s iirc.
On my sbf TI I spin 65k rpm at shifts for years. I do have the race bearings.
I’ve seen as high as 21lbs plus
Yours seems inline for how your spinning it, renegade cars would spin well into the 70s iirc.
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9. 3.33'' Blower Pulley, 15% O/D Crank pulley, Gaterback PN-4081153 115.3''
10. 17PSI
He also has a boss block so you should be seeing more than that.
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Either you have belt slip or the cooler is not efficient
Thought the same thing.. changed the tensioner out for a Reichard Racing and put three different coolers on and tested. Currently running a treadstone. Just swapped out the brand new Ti trim for a used S trim.. making the same power. Could it possibly be my custom grind camshafts not allowing it to build boost and going out the exhaust??
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Believe it was a turbo precisions bov at first, changed it to a mini race vortech bypass valve, no change. Blow through setup. Crank pulley is supposedly ati 7.5”… the car is at a reputable shop in STL.
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I don't think ATI makes a 7.5"... that's a 15% O/D crank.. I think they make a 12% so slightly smaller iirc.
So if I'm reading this right it's making 16psi and 630ish rwhp? That is spot on man.. I don't think you have a problem at all if that's the case. I'm willing to bet you have a smaller crank pulley than you believe, and with custom cams you're going to be running less boost than stock cams bro.. Go and enjoy it.
You missed the custom cams in the original post.. That would have helped.. Car is making proper psi for pulley combo and proper power.. Go and enjoy it.
Also not 1 person on this forum in the SN95 section has had as many combo's as me with a vortech lol so take that for what it's worth.
So if I'm reading this right it's making 16psi and 630ish rwhp? That is spot on man.. I don't think you have a problem at all if that's the case. I'm willing to bet you have a smaller crank pulley than you believe, and with custom cams you're going to be running less boost than stock cams bro.. Go and enjoy it.
You missed the custom cams in the original post.. That would have helped.. Car is making proper psi for pulley combo and proper power.. Go and enjoy it.
Also not 1 person on this forum in the SN95 section has had as many combo's as me with a vortech lol so take that for what it's worth.
Also have a built stroker, running on E85, short runner intake, imrc delete, Todd Warren cams/springs, V1-ti trim, 8 rib setup…could have made this power by throwing some pistons and rods in the stock block on an s trim
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All that is great and all. What’s timing at and compression at?
How high are you spinning the motor? There is so much that goes into these cars man. Even with a stroker motor. I had a big bore motor so 302ci 8:5 compression etc. so many variables hell the dyno could be off. I think you’re chasing nothing man. Go run the car
Just read where u swapped out head units. Post pics of your setup. I doubt your warren cams are the issue for real. Unless you installed them wrong.
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Also was boost the same with the ti and s trim? And wouldn’t go higher than 16psi? I think you might be pushing the bypass open if that’s the case
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Treadstone claims a 1.5psi drop. So that puts you at 17.5-18psi. I would throw a bigger bypass in there or spin it higher and see if boost keeps climbing. But judging by the two dyno runs boost is still building.
Yes boost did not change between the two head units… almost identical. Timing i believe was at 19*. My engine setup is in the pic.
Also appreciate the response to this…
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Power might be a little low, but nothing crazy.. Dyno could just be stingy.. Boost, timing, are on point for power you're making. idk why you have timing so low on 16psi and E85 though..
What's the exhaust setup? I'm going to go with either the bypass is pushing open at 16psi or the dyno is really stingy. Have you actually driven it?
What's the exhaust setup? I'm going to go with either the bypass is pushing open at 16psi or the dyno is really stingy. Have you actually driven it?
No haven’t driven it. My tuner/builder is questioning the boost it’s making.. especially since they just had an s trim car there at 16* of timing and 12th s boost pushing 580rwhp. I have full length BBK headers, off road x and slp mufflers.. think the headers are 1 5/8”…
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Only thing I’d do for that is measure the actually crank pulley honestly. See what size it really is and change the bypass to a mondo or bigger. Or pulley the sucker down with a 2.75” and see if it makes more boost lol
According to the calculator from Todd, that CR would be 8.928:1 but I don’t know how much the block or heads were decked. I think piston companies base their CR off of zero decking.
I have the same pistons in my Mach 1 with an Eagle Stroker kit.
Putting in a 44cc head brings it to 9.8:1 which is 2V heads.
But I could have also ****ed up the calculation.
Joe is very reputable though. I’d send my shit to him without hesitation.
Does two women scissoring sound like an armpit farting contest?
Just had one of the guys look for a serial number on the crank pulley.. apparently they couldn’t fond one but sent a pic and replied with….
Outside diameter overall is 7 1/4 so I'd say it's 7 inches in the belt groove
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