25% crank pulley???

Coupe5oh · 01-07-2002, 12:25 AM

I asked before but didnt get a straight answer, im talking about the crank pulley made by asp, is it safe for the street, or does it slow down accesories too much? thnx to anyone that knows their pullies.

MikeWeber · 01-07-2002, 02:33 AM

That is the standard ratio for the underdrive crank pulley. The race pulley is about 50% underdrive.
With just the street underdrive crank pulley you'll notice about 80% of the gain from the complete set with fewer problems such as low battery charge and hot engine temps idling in the summer. You will, however, need a shorter belt. The complete set is set up to use the factory length serpentine belt.
Buy it and run it, you'll be glad you did. It's cheap hp with virtually no driveablilty problems with the added bonus of longer accesory life.

Coupe5oh · 01-07-2002, 02:01 PM

Thanx dude, i didnt think anyone was gonna reply, im gonna pick it up, i do have a steeda underdrive waterpump pulley, my belt bypasses the smog pump and fits tight as heck, so i think my belt should work....what do you think?

1995MGTS · 01-08-2002, 07:57 PM

Funny you should ask because I just had my car dynoed yesterday with my 7" crank pulley (up from 6.5"). I added it to my 6psi PD blower. Unfortunetly I could only spin the engine to 5300rpm due to the belt slipping so I didn't get peak horsepower numbers, though I was up 7rwhp over my last dyno at that point. I would assume I would peak about 390-395rwhp. My entire curve moved up with the best gains at 4000rpm. At that point, I improved 30rwhp/41rwtq. Awesome little mod in my opinion. Also, I opted for the underdrive crank pulley built with it. Here is a break down.

RPM RWHP/RWTQ
2500 +10 +15
3000 +15 +20
3500 +20 +30
4000 +30 +41
4500 +15 +15
5000 +10 +10
5300 +7 +10

The pulley was the only power mod I made. I did drop my timing from 16 to 12 for safety but I am not sure how much that made a difference.

01-07-2002, 12:25 AM	#1
Coupe5oh Registered Member Join Date: Nov 2001 Location: SanAntonio, Tx Posts: 734	25% crank pulley??? I asked before but didnt get a straight answer, im talking about the crank pulley made by asp, is it safe for the street, or does it slow down accesories too much? thnx to anyone that knows their pullies. __________________ Police package 5spd 90 Lx, Stock original motor, 3.27grs, BM fan, fms 10.5 clutch, D&D quadrant, and adjuster, ADS chip, 180 stat, mac cai, mac h-pipe, mac subframe connectors, ASP crank pulley, ripper shifter, 26x10.5 M/T sport pros welds. 246 hp according to analyzer Race weight: 3,120 E.t-13.57 with 26x10.50's e.t. streets. 1.88 60' mph- 99.92 mph

01-07-2002, 02:33 AM	#2
MikeWeber Registered Member Join Date: Aug 2001 Location: Louisville, KY, USA Posts: 48	That is the standard ratio for the underdrive crank pulley. The race pulley is about 50% underdrive. With just the street underdrive crank pulley you'll notice about 80% of the gain from the complete set with fewer problems such as low battery charge and hot engine temps idling in the summer. You will, however, need a shorter belt. The complete set is set up to use the factory length serpentine belt. Buy it and run it, you'll be glad you did. It's cheap hp with virtually no driveablilty problems with the added bonus of longer accesory life. __________________ 88 NMRA Pure Street coupe 95 GT-heads, cam, exhaust, intake, road-race suspension 97 Taurus SHO-K&N, ported meter 95 Escort GT-Pacesetter header & exhaust, Weapon R intake tube

01-08-2002, 07:57 PM	#4
1995MGTS Registered Member Join Date: Mar 2001 Location: Chesapeake, VA USA Posts: 69	Funny you should ask because I just had my car dynoed yesterday with my 7" crank pulley (up from 6.5"). I added it to my 6psi PD blower. Unfortunetly I could only spin the engine to 5300rpm due to the belt slipping so I didn't get peak horsepower numbers, though I was up 7rwhp over my last dyno at that point. I would assume I would peak about 390-395rwhp. My entire curve moved up with the best gains at 4000rpm. At that point, I improved 30rwhp/41rwtq. Awesome little mod in my opinion. Also, I opted for the underdrive crank pulley built with it. Here is a break down. RPM RWHP/RWTQ 2500 +10 +15 3000 +15 +20 3500 +20 +30 4000 +30 +41 4500 +15 +15 5000 +10 +10 5300 +7 +10 The pulley was the only power mod I made. I did drop my timing from 16 to 12 for safety but I am not sure how much that made a difference. __________________ 2003 Redfire Cobra #5978 of 8394 -Pro-5.0 -DC cai -Steeda x-pipe w/cats -Steeda cat-back -Lightning pulley w/Afterburner 441rwhp/434rwtq SAE Last edited by 1995MGTS; 01-08-2002 at 08:20 PM..

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01-07-2002, 02:01 PM	#3
Coupe5oh Registered Member Join Date: Nov 2001 Location: SanAntonio, Tx Posts: 734	Thanx dude, i didnt think anyone was gonna reply, im gonna pick it up, i do have a steeda underdrive waterpump pulley, my belt bypasses the smog pump and fits tight as heck, so i think my belt should work....what do you think?