SLP 1.85 Rockers with GM ASA Cam
05-30-2014, 10:49 PM
#21
It dyno'ed 432 rwhp 393 ft lbs weather corrected, 427 390 uncorrected, track times are 11.68 121mph.
I haven't installed the rockers yet, I installed the pac 1211x springs. I installed a 9in 4:11 gears over the winter and Viking front shocks on tonight, I wanted to get them dialed in before I go changing and HP.
I haven't installed the rockers yet, I installed the pac 1211x springs. I installed a 9in 4:11 gears over the winter and Viking front shocks on tonight, I wanted to get them dialed in before I go changing and HP.
Last edited by mgood613; 05-30-2014 at 10:54 PM.
05-31-2014, 08:44 AM
#23
Actually, it does.
There are two duration's listed on nearly every cam card, and the durations are based on lift points.
The first is the advertised duration, and that's at the first measurable point off of base line, usually 0.006", or somewhere around there. Changing rocker arm ratio's will not alter this.
But, it's generally accepted that airflow doesn't really start until the valve hits 0.050" of lift. That's where you see the second set of duration numbers. This is the point that's accepted to be where the cam starts working. A higher rocker ratio not only increases the total valve opening, but also how quickly the valve gets to that effective point.
Increasing the ratio increases the effective duration by about 2-3* or so at each end. Many dyno tests have proven it to gain a little bit of power here and there; depending on the rest of the engine, of course.
There are two duration's listed on nearly every cam card, and the durations are based on lift points.
The first is the advertised duration, and that's at the first measurable point off of base line, usually 0.006", or somewhere around there. Changing rocker arm ratio's will not alter this.
But, it's generally accepted that airflow doesn't really start until the valve hits 0.050" of lift. That's where you see the second set of duration numbers. This is the point that's accepted to be where the cam starts working. A higher rocker ratio not only increases the total valve opening, but also how quickly the valve gets to that effective point.
Increasing the ratio increases the effective duration by about 2-3* or so at each end. Many dyno tests have proven it to gain a little bit of power here and there; depending on the rest of the engine, of course.
Your wording is right on !!!
05-31-2014, 03:57 PM
#24
It dyno'ed 432 rwhp 393 ft lbs weather corrected, 427 390 uncorrected, track times are 11.68 121mph.
I haven't installed the rockers yet, I installed the pac 1211x springs. I installed a 9in 4:11 gears over the winter and Viking front shocks on tonight, I wanted to get them dialed in before I go changing and HP.
I haven't installed the rockers yet, I installed the pac 1211x springs. I installed a 9in 4:11 gears over the winter and Viking front shocks on tonight, I wanted to get them dialed in before I go changing and HP.
BTW, I bet it's as fun to drive as it sounds, enjoy!
10-01-2014, 08:58 PM
#26
Just thought I would update this, so I was MPH'ing 121(11.68) with a 10bolt and 3.90 gears, I then installed a 9in and 4.11 gears and my MPH dropped to 119(11.7). I then installed the SSRA and front runners and ran 11.5 at 121. I then put 1.85 rockers and went from 26" Mickey Thompson's to Hoosier 27"x 11.5"x15 QTP and ran 11.38 at 121.5 MPH.
I need to put the 26" back on and see what it doe to the MPH.
I need to put the 26" back on and see what it doe to the MPH.
11-10-2014, 07:53 PM
#29
I got the car back on the dyno. The changes are, 1 7/8" tsp headers, 1.85 SLP rockers, Vengeance Ported Fast 92mm intake and 92mm fast throttle body, TR6 plugs, and retune. My old dyno numbers where through a 10 bolt 3.90 gears, the new ones are through a 9in 4.11.
Old 427hp 390ft lbs
New 446hp 402ft lbs
I hope to get to the track this weekend to get trap MPH.
Old 427hp 390ft lbs
New 446hp 402ft lbs
I hope to get to the track this weekend to get trap MPH.
11-24-2014, 06:36 PM
#32
Nice numbers. I am looking at possibly doing the SLP rockers as well after a FAST92/92 and ported 243s.
I made 401/401 to the wheels with my car using the GMPP ASA cam in my LS1 with untouched 241 heads, .040 head gaskets, LS6 intake, 1 3/4 lontubes and dual 3 inch exhaust.
Mine starts falling off above 6500. 350 ft lbs of torque at 3000 RPM.
I made 401/401 to the wheels with my car using the GMPP ASA cam in my LS1 with untouched 241 heads, .040 head gaskets, LS6 intake, 1 3/4 lontubes and dual 3 inch exhaust.
Mine starts falling off above 6500. 350 ft lbs of torque at 3000 RPM.
Last edited by LargeOrangeFont; 11-24-2014 at 07:19 PM.
05-02-2015, 06:15 PM
#35
I never made it back out last year, but had a chance a couple weeks ago.
I ended up dropping my race weight to 3340lbs from 3580lbs
Switched to a 28 ET Drag
Ran a couple 11.2 at 125mph and a 11.11 at 124mph
On the 11.11 run I bent the torque arm, clearanced the rear bumper with the 28's and got kicked off the track.
I ended up dropping my race weight to 3340lbs from 3580lbs
Switched to a 28 ET Drag
Ran a couple 11.2 at 125mph and a 11.11 at 124mph
On the 11.11 run I bent the torque arm, clearanced the rear bumper with the 28's and got kicked off the track.
05-21-2017, 06:55 PM
#37
I was wondering if anyone has used SLP 1.85 rockers with the GM ASA cam?
I was looking at roller rockers but keep finding issues (weight over valve, valve float ect). I was wondering if the slp stock style would be better?
I found a set for $200, 600 wouldn't be worth it in my opinion.
Also I checked PTV .083 exhaust .121 intake when I put it together, does anyone know how much they would change duration?
I have a LS1, PRC Stage 1 heads milled .30, .045 cometic head gaskets, with Howards version of the GM ASA cam. (226 236 .525 on 110 LSA), LS6 intake, 1 3/4 bbk lonetubes, no cats, open borla, 85mm throttle body 85mm maf slp lid, 160 thermostat, underdrive pulley, 42lb injectors, and tune.
I was looking at roller rockers but keep finding issues (weight over valve, valve float ect). I was wondering if the slp stock style would be better?
I found a set for $200, 600 wouldn't be worth it in my opinion.
Also I checked PTV .083 exhaust .121 intake when I put it together, does anyone know how much they would change duration?
I have a LS1, PRC Stage 1 heads milled .30, .045 cometic head gaskets, with Howards version of the GM ASA cam. (226 236 .525 on 110 LSA), LS6 intake, 1 3/4 bbk lonetubes, no cats, open borla, 85mm throttle body 85mm maf slp lid, 160 thermostat, underdrive pulley, 42lb injectors, and tune.
06-07-2017, 10:10 PM
#40
Don't know for sure, mine were milled .030 with .045 cometic gaskets.
I just had to have them cleaned up and they took off .005. I am looking into what gasket I am going to have to run now.
I was really close on my PTV, I actually had some kiss marks in the carbon on the top of the pistons.
So be careful and check, and re check.
I just had to have them cleaned up and they took off .005. I am looking into what gasket I am going to have to run now.
I was really close on my PTV, I actually had some kiss marks in the carbon on the top of the pistons.
So be careful and check, and re check.