New Supercharger installed! Need some advice on gears...

Why don't you get the vehicle tuned first then drive it and see what you think? 4.10s aren't all that steep in our cars because we have a super-duper overdrive. Sure, 4.10s wouldn't be my first choice for a positive displacement blower, but you've already got them. I guess it all depends what you want. If you aim to race from a roll, 4.10s will be nice . . . of course, this will come at the expense of traction at WOT in 1st and 2nd gear on street tires. At the track, you could overcome this by using a taller tire, like a 28". But then . . . it's all a trade off . . .
 
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damacman said:
Why don't you get the vehicle tuned first then drive it and see what you think? 4.10s aren't all that steep in our cars because we have a super-duper overdrive. Sure, 4.10s wouldn't be my first choice for a positive displacement blower, but you've already got them. I guess it all depends what you want. If you aim to race from a roll, 4.10s will be nice . . . of course, this will come at the expense of traction at WOT in 1st and 2nd gear on street tires. At the track, you could overcome this by using a taller tire, like a 28". But then . . . it's all a trade off . . .


I plan on driving the car for a bit with the 4:10's after I get it tuned to see if I like them or not but figured I would see what some of you P.D.B. guys were running as far as gears. The 4;10's were awesome when I was N.A but I kinda feel like they may make the supercharger useless down low for street driving. If 1st and 2nd are so short that I actually don't build much boost wouldn't this aid in traction but yet symbolize a lack of improvement over being N.A? Just want to make the car as fun to drive as possible after installing this new setup. Thanks for all the input guys, I appreciate it... :)
 
It really depends on your power output and how you are planning on rev'ing the engine too. If you are making enough power and trapping high enough, you might find you'll run out of rpm in 4th before the traps which means you will have no choice but to rev to a higher rpm which means more chance for boom. This is a major reason why most boosted applications are running 3.73's, but if you don't go to the track and don't care about having to shift into 5th gear around 112mph @ 6000rpms (if I remember right) then enjoy your setup as is.
 
01STG2ROUSH said:
I plan on driving the car for a bit with the 4:10's after I get it tuned to see if I like them or not but figured I would see what some of you P.D.B. guys were running as far as gears. The 4;10's were awesome when I was N.A but I kinda feel like they may make the supercharger useless down low for street driving. If 1st and 2nd are so short that I actually don't build much boost wouldn't this aid in traction but yet symbolize a lack of improvement over being N.A? Just want to make the car as fun to drive as possible after installing this new setup. Thanks for all the input guys, I appreciate it... :)

Don't confuse boost with power. Just because you don't see the boost guage go all the way over, you are still making more power than n/a. Boost is just back pressure, and back pressure is just a measure of the air you are not using to make power. So just because the back pressure doesn't have time to buld up, in 1st gear, doen't mean you are making significantly less power. Also keep in mind, that without significant work on that blower you aren't going to be making much over 330 rwhp, so those gears can make help make up for the lower power numbers.
 
01BlkGT said:
It really depends on your power output and how you are planning on rev'ing the engine too. If you are making enough power and trapping high enough, you might find you'll run out of rpm in 4th before the traps which means you will have no choice but to rev to a higher rpm which means more chance for boom. This is a major reason why most boosted applications are running 3.73's, but if you don't go to the track and don't care about having to shift into 5th gear around 112mph @ 6000rpms (if I remember right) then enjoy your setup as is.
I agree, 410's are awesome on the street with the roots blower, but you would be pushing your rpm's at the end of the quarter with a stock block...or have to shift
 
jstreet0204 said:
Don't confuse boost with power. Just because you don't see the boost guage go all the way over, you are still making more power than n/a. Boost is just back pressure, and back pressure is just a measure of the air you are not using to make power. So just because the back pressure doesn't have time to buld up, in 1st gear, doen't mean you are making significantly less power. Also keep in mind, that without significant work on that blower you aren't going to be making much over 330 rwhp, so those gears can make help make up for the lower power numbers.

I would be suprised if it only made 330. I did mild porting on the intake as the casting was horrible. Perhaps a core shift? I also assume that the other mods I listed would be a tremendous help as well. Quite honestly I expect to see somewhere around 400 give or take. From what I hear AZ Dyno really knows there stuff so here's hoping... ;)

As for the gears, my 99 GT N/A had 3:73's and was running top of 3rd or lugging 4th at the top of the 1/4. Does the 4:10 really put us at the top of 4th? I could hardly justify swapping to a 3:91 to put me in the middle...


BTW: What are the numbers for your car Jstreet? The setups seem similar... ;)
 
01STG2ROUSH said:
I would be suprised if it only made 330. I did mild porting on the intake as the casting was horrible. Perhaps a core shift? I also assume that the other mods I listed would be a tremendous help as well. Quite honestly I expect to see somewhere around 400 give or take. From what I hear AZ Dyno really knows there stuff so here's hoping... ;)

As for the gears, my 99 GT N/A had 3:73's and was running top of 3rd or lugging 4th at the top of the 1/4. Does the 4:10 really put us at the top of 4th? I could hardly justify swapping to a 3:91 to put me in the middle...


BTW: What are the numbers for your car Jstreet? The setups seem similar... ;)

Unless you've taken the supercharger apart, and really done some port work to the intake, and sealed the gaps around the intercooler, I don't see you breaking 340 rwhp. The two main problems with this blower are the extremely small/long runners, and the fact that there are large gaps around the intercooler, so hot air blows around it instead of through it. I spent weeks acid porting the runners, then I shortened them about 2 inches. I also made a plate to seal the intercooler. With all of that and the mods in my sig I made 367rwhp. I also have longtubes which I didn't see in your list. Good luck with it, but it takes a lot of work to squeeze the power out of these things.