Fuel choice for a supercharged VX

[VehiGAZ]

typical horsepower gains are about 50-60 i beleive

Take it all with a grain of salt, but I think you will have a tough time using that extra power in NYC, Gussie.

The S/C itself only bumps peak power about 25-30 hp on it's own. You need to add a high-flow intake filter, a high-flow muffler, and larger-diameter exhaust system to get the other 25-30 hp out of the boosted engine. (Does anyone have a copy of that dyno graph that Tone used to have on his site? That shows exactly where the gains are with and without exhaust work. It MUST be on this site somewhere - searchie-searchie, Gussie!)

The power increase comes at the very top of the rev range - it has virtually no effect until you hit 4000 rpm, and doesn't really make a worthwhile difference until you get over 5000 rpm.

Alpine seems to still be selling the S/C kit here. Try here too.

The kits were seldom complete, by the way - they were typically missing the throttle cable bracket, a new slightly-longer cruise-control cable, and some other miscellaneous parts. If you have to have someone fab up a bracket, add another couple hundred dollars to the bill.

I bought my kit used for $1500 and paid a shop around $750 to install it for me. I got it for a pretty good deal, all things considered, but I probably wouldn't do it again for the same price, and definitely not for full retail. Here's why:

1) If you do all of the upgrades, the 50-60 hp gain will be there, but it's not so pronounced that it's worth the ~$4700 it will take to get there ($3500 S/C kit + $750 install + $350 exhaust + $100 intake).

2) Until someone comes up with a good high-flow muffler choice, your exhaust will be brutally loud when you're done. It's easy to say that you can live with that ahead of time, but harder to follow through with it afterward.

3) The power isn't as usable as you would think, since it's all at the high end of the rev band. (Although there seems to be a noticeable gain in torque just off idle when you open up the exhaust.)

4) The difference in acceleration 0-60 time isn't very much. I don't think anyone has any reliable before-and-after times to compare, but I can't believe it's more than a 0.5 sec quicker to 60, judging by my seat-of-the-pants-accelerometer.

You'd think that almost $5000 would totally transform a vehicle's performance, but it doesn't.

[Gussie2000]

Oh,well that's a good piece of info you provided me with.

I guess i should leave my engine along

I had the same thoughts about the NYC driving condition,the reason i had to think about the S/C is because i'll problally moving to maryland near future

However your input is all i need it to make a final decision. Thanks again

[WormGod]

I agree with VehiGAZ on just about all the above.

I really only feel any added power when I am passing "at speed". On highways, it gets much easier to pass. Careful, cause once you feel that ability, you will want to do it over and over, heh. Plus, the added bonus of the intake whir and S/C whine with the exhaust rumble will satisfy you.

Backroads and city, I never feel a difference. From a stop, I dont notice any added "oomph". Though, keep in mind, I have bigger meat for wheels and tires so I am trying to turn more with that much more added weight. Someone with stock sized or smaller wheels/tires with the S/C might be able to give you their perception. However, the S/C is a plus to help turn those larger wheels/tires. Without it, it always felt pretty damned sluggish.

As for fuel, I would be hesitant to put in less than 93oct. I had knocking previous to my S/C install and only when I finally installed it and changed over to synthetic, did the knocking go away (mostly). Knocking is one thing, but to let it continue would be murder. So, probably best to follow instructions per the S/C use.