MAf Trans vs. VPC at over 475 crank HP?

[jdmspilner]

Do maf trans still work well at over 450 whp? I know a modded stock ECU will get you ther ebut would a VPC be a better choice?

 

[98spydert]

Most will agree that the VPC is the best for WOT performance but suffers for stop and go driving and part throttle performance. A 3.5" GM MAF would be best for a big horsepower daily driver/weekend warrior type vehicle IMO

 

[herostar]

I think that if you get your ECU redone by DSMChips.com to run in conjunction with whatever size injectors you have and the MAFT then you will have one nice running car that will still run on the stock ECU at high power levels. If it's a track car for drag racing the VPC is a better choice and will end up costing approximately the same.

 

[98spydert]

I think that if you get your ECU redone by DSMChips.com to run in conjunction with whatever size injectors you have and the MAFT then you will have one nice running car that will still run on the stock ECU at high power levels. If it's a track car for drag racing the VPC is a better choice and will end up costing approximately the same.

I agree, I forgot to mention the DSMchips because I take them for granted now. Injector comp and the MAFT is the best budget way to go. The very best street (dd) set up IMO is DSMLink with MAFT.

 

[Steve93Talon]

Why not use a Keydiver or DSMlink in conjunction with a VPC? Best of both worlds

 

[keymaster]

Ok, so is there any way to get the VPC reliable for street (dialy driven) use? I have one that I'm going to be installing soon with the GCC unit.

 

[danl]

The maft has gone 600whp, may have gone 700 but i'll have to double check that one. The stock ecu with extended maps is good for 450-500whp on the last map, but can of course go higher but won't fall onto new maps. The maft IMO covers anybody that would have to post such a question on a message board, ever, in life, for ever and ever. Actually, I'm not sure if you'd ever need a VPC really anymore. May as well go speed density at that point.

 

[1LE]

Ok, so is there any way to get the VPC reliable for street (dialy driven) use? I have one that I'm going to be installing soon with the GCC unit.

My 2g w/VPC & GCC is "daily drive capable", but not really pleasant in the colder weather. I don't normally since it has a cage, but it's *usable* on a daily basis. I have several friends that have daily driven 1g's with a VPC and it runs just as well as stock. 2g's are a little more picky as the VPC does fight somewhat with the stock ECU (stock ECU does some awful things that are hard to compensate for).

- Quick throttle movements will result in a stumble on power on and afterfire on quick lift (ESPECIALLY after a quick tip-in).

- Also of note, when it gets down to 50 degrees F, the car idles a little high and occasionally pops the idle up a couple hundred rpm and settles back down (O2 goes to 0 at that temp which has got to confuse the ECU). Have to add some extra fuel at idle to get it to start without cranking forever (like at the DSM vs. Subie event where it cranked for a good 10 seconds before coughing to life, all because I forgot to adjust the idle setting by 2%).

- When it gets down below 40 degrees F, it idle surges and the O2 just sits on .9 or higher. If the headlights are on and you don't pull out every bit of fuel possible, the car stumbles so bad at idle that it will occasionally stall (especially likely if you just came to a stop from expressway speeds, in town it doesn't do it nearly as much). If it does ever find a steady idle (rare), you get a "fuel mixture too rich" MIL instantly.

VPC is absolutely awesome when the temperature is in the right range and you're going WOT a lot. Great on the road course, autox, dragstrip. "OK" for rally. "Usable" for daily driving. Depends on your priorities I guess. If I had to drive it everyday of the year though, I'd probably switch to a DSMLink, 3.5" MAF setup...