Any before/after going from 60mm to VMP 67 TB?

[SCalla1384]

Does anyone have a before and after dyno sheet or track results going from the twin 60mm to VMP 67mm throttle body? Preferably on a TVS gen 1?

I made 621/557 with my 60mm on an 82mm pulley. Car also went 130.15 in the 1/4. Trying to decide if it's worth it. I also want to get some weight out of the car. Not sure what race weight is now, but I have some minor stuff now. Tubular K, full exhaust, 17x7 and 15x10 welds, aluminum driveshaft, removed sway bar. Planning on getting another 40-50lbs off the nose with a battery, jpc tubular bumper support, tubular radiator support, then just pulling the spare tire/jack.

Would love to try and go 135+ traps on 93, maybe on some better gas if need be. No e85 around here unfortunately

Thanks guys!

 

[by9468840]

Haven't been on dyno yet after the swap but my boost gauge shows about 0.5 psi increase with 79mm pulley.
I don't think you'd notice big gains unless you go really small with pulley like 75mm.

 

[11gtcs]

Haven't been on dyno yet after the swap but my boost gauge shows about 0.5 psi increase with 79mm pulley.
I don't think you'd notice big gains unless you go really small with pulley like 75mm.

I think the OP is just asking about swapping throttle bodies, not supercharger pulleys.

 

[mhyjek]

Does anyone have a before and after dyno sheet or track results going from the twin 60mm to VMP 67mm throttle body? Preferably on a TVS gen 1?

I made 621/557 with my 60mm on an 82mm pulley. Car also went 130.15 in the 1/4. Trying to decide if it's worth it. I also want to get some weight out of the car. Not sure what race weight is now, but I have some minor stuff now. Tubular K, full exhaust, 17x7 and 15x10 welds, aluminum driveshaft, removed sway bar. Planning on getting another 40-50lbs off the nose with a battery, jpc tubular bumper support, tubular radiator support, then just pulling the spare tire/jack.

Would love to try and go 135+ traps on 93, maybe on some better gas if need be. No e85 around here unfortunately

Thanks guys!

What's the cfm difference between the two throttle bodies? my friends ctsv with a maggi 2300 basically same blower but front fed when we changed from a ported 90mm to 104 we saw 1.5 lbs of peak boost and 2.5 in lower rpms i.e. below 4000 rpm so I would think it would be more significant with higher reving motor. Throttle body size is more important with tvs/roots because it affects the blower efficiency whereas in centri throttle body is after the blower. Hope that helps!

 

[BMR Tech]

I made 670 on the GT500 60mm.....with a 75mm upper and 5% lower

Swapped to the VMP 67mm and made 757.

A little deceiving....but not really. The 60mm made 670 and stayed there. The 67mm allowed me to take the RPM higher which helped result in the crazy power gain.

RPM for RPM, I think the 67mm gave me about 50rwhp IIRC

 

[BMR Tech]

Here is the before and after. I really wish the 670 graph showed RPM....but it looks like about 50-60 gain at 5250 RPM.

 

[SCalla1384]

What's the cfm difference between the two throttle bodies? my friends ctsv with a maggi 2300 basically same blower but front fed when we changed from a ported 90mm to 104 we saw 1.5 lbs of peak boost and 2.5 in lower rpms i.e. below 4000 rpm so I would think it would be more significant with higher reving motor. Throttle body size is more important with tvs/roots because it affects the blower efficiency whereas in centri throttle body is after the blower. Hope that helps!

Agreed. The roots style blower is limited by what it's able to "suck" in. Versus a centri where the air is being pushed through. I'm not sure on flow difference.

I made 670 on the GT500 60mm.....with a 75mm upper and 5% lower

Swapped to the VMP 67mm and made 757.

A little deceiving....but not really. The 60mm made 670 and stayed there. The 67mm allowed me to take the RPM higher which helped result in the crazy power gain.

RPM for RPM, I think the 67mm gave me about 50rwhp IIRC

Interesting. Thanks for the dyno charts Kelly, that's very impressive. Can't believe how much power you picked up, that's insane!

 

[466roller]

I made 670 on the GT500 60mm.....with a 75mm upper and 5% lower

Swapped to the VMP 67mm and made 757.

A little deceiving....but not really. The 60mm made 670 and stayed there. The 67mm allowed me to take the RPM higher which helped result in the crazy power gain.

RPM for RPM, I think the 67mm gave me about 50rwhp IIRC

Was this a back to back comparison with NO other changes made? Same day, dyno and tune, etc??

 

[SCalla1384]

Dyno I use stays pretty consistent. I mean if we're talking a 5-10hp swing, I'm not too concerned lol

 

[tones_RS3]

Would love to try and go 135+ traps on 93, maybe on some better gas if need be. No e85 around here unfortunately

The ONLY E85 station is located in Chelsea, MA. For me, that's on the other side of the earth. No thanks. lol Good luck!

I made 670 on the GT500 60mm.....with a 75mm upper and 5% lower
Swapped to the VMP 67mm and made 757.
A little deceiving....but not really. The 60mm made 670 and stayed there. The 67mm allowed me to take the RPM higher which helped result in the crazy power gain. RPM for RPM, I think the 67mm gave me about 50rwhp IIRC

Pretty impressive.