How to get into Boost Quicker?

[1st usa car]

Just want to know best way to get my TVS into boost at a lower RPM --

currently 2.5 pulley --- 2.4 would help but how much sooner? 250 RPMs?

10% OD crank ??

 

[08KR525]

Mash the gas pedal faster.

 

[SirShaun]

Mash the gas pedal faster.

This. It should be instantaneous.

2.4 with 10% OD (21lbs 93 Oct) VMP GEN II, but close enough. Email Tune looks like this, if you want to compare dyno charts and how power hits.

 

[Catmonkey]

I had to scratch my head on this one earlier today. Like the others that have chimed in, as soon as the engine loses vacuum (heavy throttle), the boost by-pass should slam shut and make boost. If there's a lag in that process, there's either something wrong with your tune, or your boost by-pass isn't adjusted properly or binding.

 

[- Aj -]

Different gears could help you accelerate off the line quicker


Sent from my superfast Shelby GT500

 

[fullboogie]

Mash the gas pedal faster.

LOL. That was my first thought too.

 

[Snoopy49]

Supercharger Bypass (SCB) System
The SCB system allows the high pressure air at the outlet of the supercharger to vent back into the inlet of the supercharger, equalizing the pressure. This eliminates the boost (increased pressure that the supercharger produces) for times when supercharger function is undesirable. The system uses a vacuum bypass actuator, which controls the bypass valve inside the supercharger. The system normally operates with engine vacuum applied to the upper port of the vacuum bypass actuator, while the lower port references the air pressure in the clean air tube to cancel out any pressure difference in the intake air system. The actuator is set to open (bypassing the supercharger) during high vacuum engine conditions. As the throttle is opened and engine vacuum decreases, the actuator closes to allow the supercharger to pressurize the air in the manifold.

In other words, whenever you mash the throttle, the by-pass valve closes and you create boost. Just make sure no one is beside you when you try this the first time.
P.S. Also try to avoid ditches, pedestrians, curbs, lane separators, other cars and trees.

 

[1st usa car]

I think a boost gauge would help -- because the car is fast but that thing lags like crazy. Yeah - always carefully check out the road and surrounds before I mash the gas.

 

[1st usa car]

So - basically - just use more gas if I want to get into boost earlier ---

What would a 10% od do to the performace and driveablity?? more torque, earlier in the RPM band ?

 

[Catmonkey]

Generally more boost, more power. More power, less traction. Torque band won't change and it shouldn't affect how soon it goes into boost. A 10% and 2.5" pulley on a TVS may be putting you out of pump gas range.

 

[slowbra1]

Im curious if he's getting some belt slip

 

[1st usa car]

Im curious if he's getting some belt slip

I don't think so -- that belt s tight and there is no dust buildup around the snout.

 

[1st usa car]

The car is fast -- I can still break it loose in 3rd gear but it is very predictable after my suspension mods --- Down the road I think I will get a new boost gauge that is accurate, kinda messes with my head when the OEM gauge lags so much. essentially the setup is really an on/off switch, feels like NOS if you smash the gas.

 

[Catmonkey]

The factory gauge isn't really a boost gauge in that it reads actual atmospheric pressure. It's just an electronic gizmo that infers boost. If you want to monitor boost, get a real gauge that monitors manifold vacuum/boost.

 

[1st usa car]

A 10% and 2.5" pulley on a TVS may be putting you out of pump gas range.

My setup must stay pump gas 93 octane --- I was thinking OD 10% w/ Bap or just do a simple 2.4 swap. Cant trust the OEM gauge about my PSI but I am at sea level and have ORH-Pipe.

I dunno if it matters but I don't race or track the car --- and I never hit redline --- Normally, I just play down in the rpm band - Rare occasions I my sniff 6krpm. None of that fancy powershifting or slamming it into gears - I shift like a grandma-

 

[Catmonkey]

Detonation can occur below 6,000 rpm. You could live with over 18 psi on the street, but your tuner needs to dial back your timing. I'm not sure you gain anything with that setup,

 

[1st usa car]

Detonation can occur below 6,000 rpm. You could live with over 18 psi on the street, but your tuner needs to dial back your timing. I'm not sure you gain anything with that setup,

VMP 'guide' chart below --- looks like 2.4 would be easy for my 2011 w/ ORH-pipe -- adding 10% OD to my current 2.5 will be right at 18psi, getting really close -- Guess I should call them for more feedback, I am in their backyard.

Boost chart (at sea level) with included supercharger pulleys vs crank pulley/balancer size:


SC Pulley
Stock Balancer 10% OD Balancer 15% OD Balancer

2.40"
18psi 20-21psi 21-23psi

2.50"
17psi 18-19psi 20-21psi

2.60"
16psi 16-17psi 18-19psi

2.80"
14-15psi
Step up to 2.60" recommended

Step up to 2.60" recommended





Boost is an estimate based on stock exhaust, subtract 1psi for off-road exhaust or longtube headers.

Max recommended boost at sea level is 16-17psi before fuel upgrades are required on 07-10 cars. If you are significantly above sea level you can run a more agressive pulley combination to make up for the altitude.

 

[builttodrive]

I have zero issue with my set up. Factory boost gauge basically pegs instantly the minute my right foot hits the floor. and the feeling of power is just as instantaneous as the gauge pegging.

 

[Snoopy49]

Funny, my car accelerates at the same rate with or without the boost gauge.

 

[doubleb]

I'm pretty sure you can adjust how fast the valve closes in a tune. I would make full boost instantly. Was great at the track but not to good for street driving. I could cruise at 55 mph in fifth gear @ 2000 rpm, tap the gas pedal and peg the boost gauge. It was a pain to pull out with too.