[DorkMissile]

Curious if anyone has built / tested running a centrifugal with a constant blead wastegate?

I know a couple of guys with this kind of setup on Coyote mustangs and they run incredible vs PD and a Centri with just a blowoff valve (much stronger in the mid range)

Anyone doing this kind of thing on the LT1?

[oldman]

Pretty much can take all the low and mid range boost that the blower can put out even with very small pulley sizes, so there is no need to bleed boost off.

[DorkMissile]

The whole concept works by over-spinning the SC then setting the WG at 8 or 10psi so the intake pressure is at higher pressure at lower RPM, vs at peak boost for the last little bit of the power-band.

Like I said, I drove a 2012 Coyote Mustang that had this kind of setup and it was incredibly strong vs the same setup with a BOV (both cars had Paxton SC, same intercoolers, tuned for 91, etc...) and the WG car had to be making another 100ft lbs at 4500rpm.

This is a pretty popular & proven setup, just curious if there is anyone trying it on the LT1?

[oldman]

understood, and the engine can take all the boost the supercharger can supply even with small / smallest pullies, so there is no reason to bleed boost. On the P1X they are running close to max RPM of the unit at red line of the engine.

[Matt@Tick]

We have done it, I don't like it lol. Give me the boost all the time. I'll change power in the tune.

[TJay74]

I have a D1SC on my SS 1LE and even with the Tial 2" BOV I can still tell that the supercharger is boosting power in the lower RPM levels. I can already break the tires loose at half throttle from 2k RPM's, I cant imagine wanting even more low RPM HP or TQ on a RWD setup. if the Camaro was AWD it would be a whole nother world.

[tireslayer0331]

I was toying with this idea in my head for a while. The ability to hookup a boost controller to the wastegate would be awesome. You could run different power level maps or boost by gear if you have the correct hardware. I'm still interested in it! What was the setup on your mustang like?

[oldman]

Originally Posted by tireslayer0331

I was toying with this idea in my head for a while. The ability to hookup a boost controller to the wastegate would be awesome. You could run different power level maps or boost by gear if you have the correct hardware. I'm still interested in it! What was the setup on your mustang like?

OK I see, There is to my mind no issue running a boost controller and the smallest pulley to bring your blower to max RPM just above engine red line. You would be bleeding off boost at say 5000 RPM up dependent on gear and / or fuel quality. I don't see any issue at all, You would be looking at a D1X on a 6750 rpm cam , fuel cut at 6800 with a 3.75 pulley say 12 to 14 PSI on the top is what the blower will put out, set the wastegate on 93 octane to 10 PSI, and it should get there 500 to 750 RPM sooner. OK gotcha.. my bad.

I've noted that the P1X guys seem to be taking all the boost the 3.75 pulley is bringing them. So it we are really talking a D1X on pump fuel with 3.75 pulley as the D1X has a lower RPM limit for the wheel and the wheel puts out way more boost at any RPM.

[oldman]

OK so here is the link to max blower speeds for Procharger:https://www.procharger.com/automotiv...-superchargers

Given my 6800 RPM fuel cut, 4.10 internal ratio and 62000 RPM max blower, I can do some Math: um for sure the max shaft speed for the blower is: 15,122 RPM. The smallest pulley that I've seen for the bower is 3.75" which has a circumference of: 11.781" bust the crank pulley from procharger diameter: 7.65 and get a circumference of 24.033"

so at 6800 rpm the belt travels 6800 x24.033" = 163,424" per minute this goes to 13,872 RPM at the supercharger shaft or about 56,874 rpm at the wheel. Heck you can even go to a smaller wheel,especially on the P1X

6800 RPM, 163,424" of belt speed will yield:
56,874 blower RPM for the 3.75" pulley
53,319 blower RPM for the 4.0" pulley
and the pulley that I run the 4.5"
47,396 blower RPM for the 4.5" pulley, heck it is hardly spinning.... LOL

going the other crazy way:
60,973 RPM for the 3.5 pulley... near max bursting RPM. The D1X at this point (never saw a Procharger wheel map), I have worked with billet wheels and Powerdyne, the unit should be flowing 1000 HP worth of air. So say the ride is rated at 800 engine HP, that would mean your one or two BOV would be bleeding 200 HP worth of boost... shiznet is gonna be loud..

Probably if the make it, at 3.65 would give a little more headroom. for the P1X this should be fine.
Others please check my math.


3.25 pulley
65,624 RPM which is boom for the blower

[tireslayer0331]

Originally Posted by oldman

OK so here is the link to max blower speeds for Procharger:https://www.procharger.com/automotiv...-superchargers

Given my 6800 RPM fuel cut, 4.10 internal ratio and 62000 RPM max blower, I can do some Math: um for sure the max shaft speed for the blower is: 15,122 RPM. The smallest pulley that I've seen for the bower is 3.75" which has a circumference of: 11.781" bust the crank pulley from procharger diameter: 7.65 and get a circumference of 24.033"

so at 6800 rpm the belt travels 6800 x24.033" = 163,424" per minute this goes to 13,872 RPM at the supercharger shaft or about 56,874 rpm at the wheel. Heck you can even go to a smaller wheel,especially on the P1X

6800 RPM, 163,424" of belt speed will yield:
56,874 blower RPM for the 3.75" pulley
53,319 blower RPM for the 4.0" pulley
and the pulley that I run the 4.5"
47,396 blower RPM for the 4.5" pulley, heck it is hardly spinning.... LOL

going the other crazy way:
60,973 RPM for the 3.5 pulley... near max bursting RPM. The D1X at this point (never saw a Procharger wheel map), I have worked with billet wheels and Powerdyne, the unit should be flowing 1000 HP worth of air. So say the ride is rated at 800 engine HP, that would mean your one or two BOV would be bleeding 200 HP worth of boost... shiznet is gonna be loud..

Probably if the make it, at 3.65 would give a little more headroom. for the P1X this should be fine.
Others please check my math.


3.25 pulley
65,624 RPM which is boom for the blower

You are definitely right about it being loud, never thought about that. The IATs would probably be quiet a bit higher compressing that much more air and bleeding it off. I was interested in this setup for more practical uses over a performance gain. I thought it would be nice to have a car with a high boost map and a low boost map, have one putting out 900+hp and another for 500-600hp. Where I live it gets cold and 900+hp in a rwd car is only useful for a few months of the year! The controllability of boost on a turbo setup is something I am completely envious of, but I love my procharger setup.