LSX Block 427ci, PRC 265cc Ls7 Heads
02-07-2012, 09:16 PM
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LSX Block 427ci, PRC 265cc Ls7 Heads Plans for the Spring LSX Block 427ci, 11.2:1 CR, 150 Fogger
PRC 265cc Ls7 Heads, Linked Bar Lifters
247/255 .670 .670 112 LSA+4 Hydro Roller
Fast 102/102 Combo
Drive Line:
Built Th400, Yank 4k Stall, Moser 9in Wave Trac 3.89 Clogs
Leaven off the T-Brake n 2 Step Trying for High 9s w No Spray
Est WHP off the Juice 580ish
What ya think?... Trying to see if any else had thrown together a combo like this n gotten around what Im looking for Track times and Power
PRC 265cc Ls7 Heads, Linked Bar Lifters
247/255 .670 .670 112 LSA+4 Hydro Roller
Fast 102/102 Combo
Drive Line:
Built Th400, Yank 4k Stall, Moser 9in Wave Trac 3.89 Clogs
Leaven off the T-Brake n 2 Step Trying for High 9s w No Spray
Est WHP off the Juice 580ish
What ya think?... Trying to see if any else had thrown together a combo like this n gotten around what Im looking for Track times and Power
02-09-2012, 05:29 PM
#2
Sounds interesting. Subscribed
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02-09-2012, 08:29 PM
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you have no concept of how much power a th-400 and converter eat up for power. I bet your 2400 stall converter was locked for thoes numbers
Last edited by SSPerformance; 02-09-2012 at 08:36 PM.
02-09-2012, 09:10 PM
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I know this short block made 520whp threw a th350 trans and a 12bolt w PRC 237cc Cathedral Port heads and a Fast 102/102 combo and a little smaller cam.....Car went 10.30s Guy was local we watched it run at the track
I bought the Long Block off him sold the heads and Cam and Going w the PRC 265cc Heads and the Cam in the OP
My Car last yr w a Stock Longblock MS4 Cam, Fast 102/92 combo w th400 and the 9in made 402whp 3320lbs w stock front K n A arms went 11.26@121mph Leaven at 2k ft braking
And Sommer86 now has my Fast 102 on his car lol
I bought the Long Block off him sold the heads and Cam and Going w the PRC 265cc Heads and the Cam in the OP
My Car last yr w a Stock Longblock MS4 Cam, Fast 102/92 combo w th400 and the 9in made 402whp 3320lbs w stock front K n A arms went 11.26@121mph Leaven at 2k ft braking
And Sommer86 now has my Fast 102 on his car lol
02-10-2012, 06:15 AM
#14
I just noticed that he has the 265 PRC not the 285 PRC which (when I bought them) have the option of Carrie's casting (ETP) now Mast Motors.
02-10-2012, 08:55 AM
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Comparing dyno numbers from car to car and dyno to dyno is essentially useless.
02-10-2012, 09:54 AM
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So say my car was 6spd whats it supposed to make 470whp the baddest stock LB Ls1 on this site?! Dont think so.... Prb 420ish area
02-10-2012, 10:38 AM
#18
I know this short block made 520whp threw a th350 trans and a 12bolt w PRC 237cc Cathedral Port heads and a Fast 102/102 combo and a little smaller cam.....Car went 10.30s Guy was local we watched it run at the track
I bought the Long Block off him sold the heads and Cam and Going w the PRC 265cc Heads and the Cam in the OP
My Car last yr w a Stock Longblock MS4 Cam, Fast 102/92 combo w th400 and the 9in made 402whp 3320lbs w stock front K n A arms went 11.26@121mph Leaven at 2k ft braking
And Sommer86 now has my Fast 102 on his car lol
I bought the Long Block off him sold the heads and Cam and Going w the PRC 265cc Heads and the Cam in the OP
My Car last yr w a Stock Longblock MS4 Cam, Fast 102/92 combo w th400 and the 9in made 402whp 3320lbs w stock front K n A arms went 11.26@121mph Leaven at 2k ft braking
And Sommer86 now has my Fast 102 on his car lol
BTW, thanks for the heads/cam. Going to check the combustion cc's tonight since I had them decked (just to make sure they were square). Order my gaskets on Monday and put it together next week.
Still on the fence with running my current cam or the new one I got from you. Performance Trends engine analyzer has shown to be very accurate when I have modeled motors (with in 2% through out the full curve, and hitting peak rpms +/- 100rpm). Says I will loose low end TQ/peak TQ and make the same peak HP at the same RPM. I might try them both one weekend at the track.
I agree it will be hard to make an extra 180rwhp with out a LOT of changes. Also consider the 520rwhp that was once made with the 237's/427ci combo was through a TH350, not a TH400.
Take the above example of my old 347 with stock ported heads against my 418 with AFR 225 heads. Same compression (11.1-1), intake(Super Victor), Dominator TB, 1 3/4 stepped to 1 7/8 headers, and drivetrain (80E, 4,500 verter, 12 bolt, 4.56's, and 315/60/15 DR's). Unlocked I picked up 67rwhp, locked 72rwhp.
I am hoping to make 520rwhp with my new heads, higher compression, better headers and Power Glide. But more importantly is going 10.5x..
02-10-2012, 11:08 AM
#19
Once you go with a th400 your dyno #'s can vary huge. Our real street rhs 461, trickflow 265, solid roller .800 lift, beck intake, 15:1 comp made 861 on the engine dyno and dynoed 590whp. It did run 141 mph on motor though. Once you go with a glide, th350, th400 toss the chassis #'s in the can.
02-10-2012, 11:29 AM
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Just an FYI, my 347ci motor made 449rwhp through an 80E locked and only 402rwhp unlocked. Same exact drivetrain behind my 418 with AFR 225 heads made 521rwhp locked and 469rwhp unlocked. I saw right about a 10% loss with my 4,500 converter unlocked (BTW that converter instantly became a 5,800ish converter behind the 418)
BTW, thanks for the heads/cam. Going to check the combustion cc's tonight since I had them decked (just to make sure they were square). Order my gaskets on Monday and put it together next week.
Still on the fence with running my current cam or the new one I got from you. Performance Trends engine analyzer has shown to be very accurate when I have modeled motors (with in 2% through out the full curve, and hitting peak rpms +/- 100rpm). Says I will loose low end TQ/peak TQ and make the same peak HP at the same RPM. I might try them both one weekend at the track.
I agree it will be hard to make an extra 180rwhp with out a LOT of changes. Also consider the 520rwhp that was once made with the 237's/427ci combo was through a TH350, not a TH400.
Take the above example of my old 347 with stock ported heads against my 418 with AFR 225 heads. Same compression (11.1-1), intake(Super Victor), Dominator TB, 1 3/4 stepped to 1 7/8 headers, and drivetrain (80E, 4,500 verter, 12 bolt, 4.56's, and 315/60/15 DR's). Unlocked I picked up 67rwhp, locked 72rwhp.
I am hoping to make 520rwhp with my new heads, higher compression, better headers and Power Glide. But more importantly is going 10.5x..
BTW, thanks for the heads/cam. Going to check the combustion cc's tonight since I had them decked (just to make sure they were square). Order my gaskets on Monday and put it together next week.
Still on the fence with running my current cam or the new one I got from you. Performance Trends engine analyzer has shown to be very accurate when I have modeled motors (with in 2% through out the full curve, and hitting peak rpms +/- 100rpm). Says I will loose low end TQ/peak TQ and make the same peak HP at the same RPM. I might try them both one weekend at the track.
I agree it will be hard to make an extra 180rwhp with out a LOT of changes. Also consider the 520rwhp that was once made with the 237's/427ci combo was through a TH350, not a TH400.
Take the above example of my old 347 with stock ported heads against my 418 with AFR 225 heads. Same compression (11.1-1), intake(Super Victor), Dominator TB, 1 3/4 stepped to 1 7/8 headers, and drivetrain (80E, 4,500 verter, 12 bolt, 4.56's, and 315/60/15 DR's). Unlocked I picked up 67rwhp, locked 72rwhp.
I am hoping to make 520rwhp with my new heads, higher compression, better headers and Power Glide. But more importantly is going 10.5x..
I just dont see why it wouldn't pick up some power on the dyno switching to the Ls7 stuff over what I sold U. Above everything It should shine at the track pretty good
I was just kinda surprised when we dynoed my Stock LB build w the TH400 vs my buddys same build but w a 6spd n 10bolt his car made 25whp more than mine n we dynoed on the same dyno back to back