Underdrive pulley installed!!!
Thread Starter
Melting Slicks
Joined: Jun 2001
Posts: 2,525
Likes: 1
From: Sarasota, FL
Underdrive pulley installed!!!
Not too bad a job, took it for a spin. Definitely makes a difference in charging @ idle. 800-900 rpm charges fully tho. Charges at about 12.7v in gear, at a light, with radio on. Around 12.1v in gear at a light with lights & heater on. I essentially never turn on AC so I am not worried about that. For the who care the stock belt on my '88 is 92.2 inches long, the new belt is 89.5 inches. I just cut the old one and then wrapped it around everything to measure the difference. Thanks for the help, we'll see if it makes a difference in ET's. It suer seemed to for Vic. I have a new 2 1/2 inch Borla/dynomax catback also, so new times will reflect both chagnes. Bandimere Speedway here I come!!!
Thread Starter
Melting Slicks
Joined: Jun 2001
Posts: 2,525
Likes: 1
From: Sarasota, FL
Re: Underdrive pulley installed!!! (KYVette90)
Dunno yet, didn't really get on it. My "seat" is evidently not very well calibrated, as things I have done that felt like a big change made no or actually negative cahnges in 1/4 mi. ETs. I wouldn't really expect a big SOTP change for this, I would expect any real gains to be at high RPM.
Race Director
Joined: Oct 2000
Posts: 16,477
Likes: 1
From: Enter Post Count Here
Re: Underdrive pulley installed!!! (BobMachus)
That was one of the only mods we did to my buddies truck (454SS), that you could actually feel a big SOTP gain. He gained .2 in the 1/4 mile.
:cool: mod, I've been thinking about it, but I'd need a more efficient alternator for the stereo I want to put in the car.
:cool: mod, I've been thinking about it, but I'd need a more efficient alternator for the stereo I want to put in the car.
Safety Car
Joined: Jun 2000
Posts: 4,870
Likes: 25
From: Long Island, NY
Re: Underdrive pulley installed!!! (BobMachus)
Good job Bob, it wasn't too bad was it ?
When are you heading to the track ?
BTW, whenever I do a small mod, I never feel any SOTP gains.
The only time I felt a gain was with the Torque convertor and the TPIS catback exhaust.
Post your track results when you get them.
Vic
When are you heading to the track ?
BTW, whenever I do a small mod, I never feel any SOTP gains.
The only time I felt a gain was with the Torque convertor and the TPIS catback exhaust.
Post your track results when you get them.
Vic
Burning Brakes
Joined: Nov 2000
Posts: 1,040
Likes: 2
From: BowlingGreen KY
Re: Underdrive pulley installed!!! (Oh My)
Which underdrive pulley would you all reccommend? If you instal an underdrive crank pulley and a larger alternator pulley wouldn't the two cancel out each others potential effects?
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Thread Starter
Melting Slicks
Joined: Jun 2001
Posts: 2,525
Likes: 1
From: Sarasota, FL
Re: Underdrive pulley installed!!! (65Z01)
What he said. I suspect that the alternator load is much less than water and PS pumps (and A/C if it is on). It definitely charges less now, but the only time I would worry is stuck in bumper to bumper traffic for a LONG time.
Instructor
Joined: Dec 2000
Posts: 184
Likes: 0
From: Birmingham, AL , USA Alabama
Re: Underdrive pulley installed!!! (BobMachus)
Hello everyone,
I put an underdrive kit on my car last year. It ran hot and the alt was turning too slow and made the lights go dim at an idle. Had one heck of a time finding a serpentine to fit. Couldn't tell any difference in power. Took it back off and it's for sale at half price if anyone wants it. I got it from Eklers. It was the two pully kit and belt. Alt pulley, crank pulley and belt. My car is an '89 and I swear all the mods I have put on it I don't think anything would make it run any faster other than NOS. AND I have thought about that.
Jack
I put an underdrive kit on my car last year. It ran hot and the alt was turning too slow and made the lights go dim at an idle. Had one heck of a time finding a serpentine to fit. Couldn't tell any difference in power. Took it back off and it's for sale at half price if anyone wants it. I got it from Eklers. It was the two pully kit and belt. Alt pulley, crank pulley and belt. My car is an '89 and I swear all the mods I have put on it I don't think anything would make it run any faster other than NOS. AND I have thought about that.
Jack
Instructor
Joined: Dec 2000
Posts: 184
Likes: 0
From: Birmingham, AL , USA Alabama
Re: Underdrive pulley installed!!! (KYVette90)
Because believe it or not the belt that came with the kit didn't fit. Luckily I had a friend in the Auto Parts business that let me try and try for a fit. Obviously either Eklers made a mistake or I had a pulley that wan't stock. BUT either way I think the underdrive kit was a waste of time. If anyone thinks different then I have a deal for you.
Jack
Jack
Thread Starter
Melting Slicks
Joined: Jun 2001
Posts: 2,525
Likes: 1
From: Sarasota, FL
Re: Underdrive pulley installed!!! (jer35073)
FYI those are $250 AL and $150 black powder coated steel in Eckler's. Post 'em in the C4 Parts for Sale Forum and you might get a response.
Safety Car
Joined: Jun 2000
Posts: 4,870
Likes: 25
From: Long Island, NY
Re: Underdrive pulley installed!!! (BobMachus)
I am really looking forward to Bandimere opening. I am in on that Vigilante GP also, so that should help.
Vic
Thread Starter
Melting Slicks
Joined: Jun 2001
Posts: 2,525
Likes: 1
From: Sarasota, FL
Re: Underdrive pulley installed!!! (Vic'89)
Best 60' to date 2.286, most in the high 2.3's and low 2.4's. Due to 2.73's and 5800+ feet of elevation. Hopefully the Vigilante will bring down those 60' and ETs.
Bob
Bob