Better turbo response - more w/g spring or more boost controller?
11-11-2014, 12:56 AM
#2
Hands down the bigger the spring in the gate the sooner it will spool due to a tighter seat pressure.
On turbo motorcycles we set them up the biggest spring we can get before it will spin, then ramp in boost after that.
On turbo motorcycles we set them up the biggest spring we can get before it will spin, then ramp in boost after that.
11-11-2014, 02:12 PM
#3
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stronger spring, or apply pressure to top port as well.
But it really depends how soft the spring is already and EGBP actually blowing against the spring.
Swapping could make a difference, or none at all.
But it really depends how soft the spring is already and EGBP actually blowing against the spring.
Swapping could make a difference, or none at all.
11-11-2014, 08:14 PM
#4
My boost gauge zero's out at about 3500 rpm and goes positive. I have a 12psi spring in there now. I kinda think boost should be coming in a bit sooner which got me thinking about all this. I once pulled the reference line off a w/g off another turbo motor I put together and the difference in turbo response was incredible.
Is it possible that a wastegate could be cranking open before there is boost? I dont think backpressure would be enough of an issue at that low of an rpm (<3500) to crack a w/g open.
Is it possible that a wastegate could be cranking open before there is boost? I dont think backpressure would be enough of an issue at that low of an rpm (<3500) to crack a w/g open.
11-12-2014, 09:27 AM
#7
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I have a tv7511 (old t6 framed Garrett) and was tuned on 17lbs with the heaviest spring in the WG, no boost controller. I changed heads and converter and wanted to back it down a little bit and sneak back up on it and make sure my tune didn't need too much change. I put the next size smaller spring in maybe 12-13lbs, it spooled faster to 17 than it did to 13. From 0-3psi or so I bet not much is happening, but you would be surprised how much a WG starts cracking when there is manifold pressure pushing on the diaphragm, and maybe 2x+ that of backpressure pushing on the valve itself. I'm pretty sure the eboost2 applies pressure to the top port holding it closed until where you specify to apply pressure to the bottom port.
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11-12-2014, 08:58 PM
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Wastegate spring, for sure.
I've got the 475/83/t4 1.0 on my LQ9 and the turbo seemed kind of lazy with the light JGS spring (7 psi). I was using my eboost street to raise the boost from there.
I changed out the spring to the heavy JGS spring and the turbo came alive. I'm seeing 16-18 psi and the spool is so much faster now it's not even funny, almost too fast....serious traction problems with 315 MT ET streets. But it's pushing 5000+ lbs of extended cab truck to almost 126 mph in the 1/4th with issues still to work out. You're going to fly in that little Stang.
I've got the 475/83/t4 1.0 on my LQ9 and the turbo seemed kind of lazy with the light JGS spring (7 psi). I was using my eboost street to raise the boost from there.
I changed out the spring to the heavy JGS spring and the turbo came alive. I'm seeing 16-18 psi and the spool is so much faster now it's not even funny, almost too fast....serious traction problems with 315 MT ET streets. But it's pushing 5000+ lbs of extended cab truck to almost 126 mph in the 1/4th with issues still to work out. You're going to fly in that little Stang.
11-12-2014, 09:42 PM
#11
Wastegate spring, for sure.
I've got the 475/83/t4 1.0 on my LQ9 and the turbo seemed kind of lazy with the light JGS spring (7 psi). I was using my eboost street to raise the boost from there.
I changed out the spring to the heavy JGS spring and the turbo came alive. I'm seeing 16-18 psi and the spool is so much faster now it's not even funny, almost too fast....serious traction problems with 315 MT ET streets. But it's pushing 5000+ lbs of extended cab truck to almost 126 mph in the 1/4th with issues still to work out. You're going to fly in that little Stang.
I've got the 475/83/t4 1.0 on my LQ9 and the turbo seemed kind of lazy with the light JGS spring (7 psi). I was using my eboost street to raise the boost from there.
I changed out the spring to the heavy JGS spring and the turbo came alive. I'm seeing 16-18 psi and the spool is so much faster now it's not even funny, almost too fast....serious traction problems with 315 MT ET streets. But it's pushing 5000+ lbs of extended cab truck to almost 126 mph in the 1/4th with issues still to work out. You're going to fly in that little Stang.
11-12-2014, 10:19 PM
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Off the footbrake I hit 9.2 psi and 4544 rpm at 47.8% TPS and boost essentially instantaneously hits 16-17 psi in 1st gear.
I think I've probably touched the limit of this small 475, so I'm thinking about swapping to the 480/96/t4.
11-13-2014, 05:58 AM
#13
I couldn't tell you that since I've only run it on the track since I put the heavy spring in and I brake boost off the line.
Off the footbrake I hit 9.2 psi and 4544 rpm at 47.8% TPS and boost essentially instantaneously hits 16-17 psi in 1st gear.
I think I've probably touched the limit of this small 475, so I'm thinking about swapping to the 480/96/t4.
Off the footbrake I hit 9.2 psi and 4544 rpm at 47.8% TPS and boost essentially instantaneously hits 16-17 psi in 1st gear.
I think I've probably touched the limit of this small 475, so I'm thinking about swapping to the 480/96/t4.
11-20-2014, 08:48 AM
#14
I did a test and disconnected the boost reference line to the bottom of the w/g and put it on top. Spool is exactly the same, so I can assume the gate isnt cracking open.
My converter is pretty loose at part throttle so I can only assume its not loading the engine as well as some of the better units.
My converter is pretty loose at part throttle so I can only assume its not loading the engine as well as some of the better units.