PRC Stage 1 243 heads, MS4 dyno
#1
PRC Stage 1 243 heads, MS4 dyno
Had a beautiful 2002 SS come to the dyno yesterday. The car had stock 5.7 short block with no valve reliefs, an unmilled set of PRC stage 1 cnc ported 243 heads, MS4 cam, 1 3/4" headers, true duals, M6, LS6 intake, and MAFless tune.
The combo was speed density tuned by another tuner and it seemed to be in good running order when it arrived. The owner was not happy with the power it had made when it was run during a club dyno day. Judging by the solid mods, we all felt the car should be in the 440 rwhp range. Kurt Decker and I strapped the car down for a baseline run. It made 424rwhp/389rwtq. Good, but not great. When I logged the run, I noticed that the timing was good and the A/F ratio was certainly within the realm of making solid power. Something was holding it back. Something was.
Looking at his airlid assembly, the customer's SS had the optional SLP 345hp package which included the Blackwing air lid. The opening of the air lid was only about 1/2" across. Talk about a restriction. We unbolted the radiator support to raise the air lid (to give it a 1" opening). We redynoed. Power rose to 434/395 just be raising the air box! Next, we replaced the SLP Blackwing air lid with a UPD air lid. Power rose to 440/400. So with no additional tuning, the power gain was 16rwhp and torque gain was 11 rwtq. Moral of the story? Don't always blame the heads and cam when the power is not as good as it should be. Sometimes you have to look for hidden power in other areas. In this case, the air lid assembly was way too restrictive. The before and after dyno sheet is below.
The combo was speed density tuned by another tuner and it seemed to be in good running order when it arrived. The owner was not happy with the power it had made when it was run during a club dyno day. Judging by the solid mods, we all felt the car should be in the 440 rwhp range. Kurt Decker and I strapped the car down for a baseline run. It made 424rwhp/389rwtq. Good, but not great. When I logged the run, I noticed that the timing was good and the A/F ratio was certainly within the realm of making solid power. Something was holding it back. Something was.
Looking at his airlid assembly, the customer's SS had the optional SLP 345hp package which included the Blackwing air lid. The opening of the air lid was only about 1/2" across. Talk about a restriction. We unbolted the radiator support to raise the air lid (to give it a 1" opening). We redynoed. Power rose to 434/395 just be raising the air box! Next, we replaced the SLP Blackwing air lid with a UPD air lid. Power rose to 440/400. So with no additional tuning, the power gain was 16rwhp and torque gain was 11 rwtq. Moral of the story? Don't always blame the heads and cam when the power is not as good as it should be. Sometimes you have to look for hidden power in other areas. In this case, the air lid assembly was way too restrictive. The before and after dyno sheet is below.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
#3
Do a search for 98Aggie, I think he has some leftover new ones that he might sell.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
#4
Thx to Patrick G and 98Aggie (Kurt) for finding that hidden power! I was very surprised by raising the lid (free mod) and UPD lid made in power. Of course I couldn't leave the shop without buying the lid on the spot!
Thanks again!
Thanks again!
#7
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I am unfamiliar with this company/brand lid. Do you have a photo of the product and/or images I the differences between this lid and other common lids?
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#11
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I have had 4 different lids over the years and all them were quality products. To my knowledge the FT's lid is the best out there but im always looking for the next big thing No MAF here just a good ole speed density tune for me
#13
This particular car had NO MAF, so from a flow standpoint, there was no MAF restriction.
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
#14
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so those stage 1 243s seem to work pretty well, huh? I have the stage 1 317s 68cc....I'm interested to see what I pick up on an otherwise stock internal motor for the time being.
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Pat whats the deal with the tq curve and the loss in power at 4000ish....i got the same bs...some seem to be a nice smooth tq curve some have this horrible dip in them....is it the cam not designed well for the cubes or what?
heres mine for reference of what im talking about in the tq curve....didnt matter if we made it fat, lean, add timing, take out timing couldnt get rid of these hills
mines a stock short 346 with TFS 61cc 215's a 236 238 601 605 113+2 comp xe xer grind with a fast 92 and all the boltons on my Z06
heres mine for reference of what im talking about in the tq curve....didnt matter if we made it fat, lean, add timing, take out timing couldnt get rid of these hills
mines a stock short 346 with TFS 61cc 215's a 236 238 601 605 113+2 comp xe xer grind with a fast 92 and all the boltons on my Z06
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Last edited by 98Aggie; 02-09-2009 at 07:58 PM.