Low Boost 347

[deuce_454]

Originally Posted by ka67_72

a larger diameter idler pulley

i take it the larger diameter idler pulley is to increase belt contact (either belt tension or contact angle) on the driven pulley... (that or the idler part ot the sentence was a typo..)

last resort is a cogged belt, which would be my next suggestion btw

[ka67_72]

The idler adjustment was maxxed out so the larger diameter idler is to increase tension and try to wrap the belt a little better. The car is pretty much useless traction wise so I've talked him into putting some southside or megabite suspension under it before I rack up a bunch of money trying to make more power. He's going to get some track bite for the belt and drive it for a while. If he wants more power after that, I'm first going to relocate the idler towards the supercharger. I was also thinking about cogged belts and drive pulleys. I was going to check with McMaster Carr. What do you recommend as a vendor for cogged drive parts? The owner asked me today if the computer would compensate for running 87 octane without the water injection. If it had a knock sensor it would, but I tuned it on 93 with water so more boost may not be a good idea for now.

Thanks,
Kevin

[3kidsnotime]

What CFM is your head unit rated at and what RPM. Also you say you cant get the shorter belt on, I have run into this alot with customers, how are you putting it on? you need to actually put it on the blower first then the crank if you need to bump the engine.

[ka67_72]

I could probably get the shorter one on that way. I just didn't know if I should try to force it. I just sent an e-mail to Powerdyne to try to get some flow info.

Thanks,
Kevin

[ka67_72]

He picked up the car on Saturday and is very happy with the improvements in drivability and power output. I never got a response from Powerdyne, but we're making just over six pounds now and according to the EMS using the calibration data I input from the MAF cal we're flowing 64 lb/min of air. I don't know a good way to estimate power from that. Except for the motor, a six point cage, and subframe connectors the car is stock and severely traction limited. We'll see if he comes back for more after he get's some traction.

Thanks,
Kevin

[AllSpeedAndy]

Glad to see customer happy...in some of our experiences with the ProCharger stuff, we have seen them pull the boost number on the dyno after some track bite treatment, then go for a real world drive and see considerably less boost on the street, but lots of spinning and sliding...So is it plauseble that with the spinning of the tires, the load on the engine is decreased as traction goes away causing the thing not to pull the boost as it was locked in and hooking on the dyno? Or should this cause a spike in boost presure?