LSX 427 w/ TFS GenX 255 LS3's/ FAST 102
10-12-2014, 10:28 PM
#1
LSX 427 w/ TFS GenX 255 LS3's/ FAST 102 Hey Guy's
Just picked up my new engine from LME in Houston,Tx on Friday afternoon. My car has been down since early May due to a timing chain & gear failure in the L92 setup that is in my sig. Really a freak thing that just happened with no warning, was able to salvage the complete shortblock and only real damage was 8 bent valves. Was lucky compared to how bad it could have been.
One of my friends bought the 6.2 from me for a good price, and that opened the door for me to be able to build a larger engine. My first thought was to build a 416" LS3 stroker. I purchased a pair of TFS GenX 255 LS3's from a member here on Tech, they had tow previous owners but neither ever used them,
so I got a good deal on them.
After some phone conversations with Bryan @ Late Model Engines I decided to bite the bullet and build a LSX based 427 and use the TFS 255's & the FAST 102/102mm setup from my previous setup.
Engine specs are:
GM LSX block
Callies Compstar 4.0" stroke crank
Callies Compstar 6.125" rods
ARP main & head stud kits
Wiesco K463x125 -2.8cc forged pistons/ 12.0 compression w/65cc chambers
Cometic .051" head gaskets
TFS GenX 255 LS3's milled to 65cc Chambers, no additional port work
Pacaloy 1208X dual springs w/titanium retainers
FAST LSXR 102mm/ FAST 102mm TB
52 lb injectors/ ZL1 Camaro
Cam Motion billet core Hyd Roller Camshaft
248*/264*@ .050" with .694"/ .681" lift on a 112 + 4 LSA
Comp Cams short travel Hyd Roller lifters
3/8" x .120" wall pushrods
Crower Stainless Shaft mounted 1.8 ratio rocker arms
Rollmaster double roller timing set
Melling 10295 ported oil pump
Moroso 21150 F-Body Aluminum oil pan
ATI F-body damper
Did'nt really know what to expect for power, as always was hoping for more. But, I'm sure its gonna be fun for a street car and I can always add that big shot of juice when I feel the need.
They also made a couple of pulls with a Holley Hi-Ram intake w/90mm TB. The Hi-Ram made about 20 more peak HP, peaking @ 6800 rpm and carrying pretty flat until the 7000 rpm shutoff, but was down by 30 lb/ft tq across the entire range.
Here are the dyno charts and readouts for the FAST 102 intake, as a side note they used a 90mm DBW TB for the dyno runs since thay are set up for drive by wire. So, just wondering how much power is in running my 102 mm TB? In the print out you can see where there was a vacuum during a majority of the pull from 4600 rpm on up?
Just picked up my new engine from LME in Houston,Tx on Friday afternoon. My car has been down since early May due to a timing chain & gear failure in the L92 setup that is in my sig. Really a freak thing that just happened with no warning, was able to salvage the complete shortblock and only real damage was 8 bent valves. Was lucky compared to how bad it could have been.
One of my friends bought the 6.2 from me for a good price, and that opened the door for me to be able to build a larger engine. My first thought was to build a 416" LS3 stroker. I purchased a pair of TFS GenX 255 LS3's from a member here on Tech, they had tow previous owners but neither ever used them,
so I got a good deal on them.After some phone conversations with Bryan @ Late Model Engines I decided to bite the bullet and build a LSX based 427 and use the TFS 255's & the FAST 102/102mm setup from my previous setup.
Engine specs are:
GM LSX block
Callies Compstar 4.0" stroke crank
Callies Compstar 6.125" rods
ARP main & head stud kits
Wiesco K463x125 -2.8cc forged pistons/ 12.0 compression w/65cc chambers
Cometic .051" head gaskets
TFS GenX 255 LS3's milled to 65cc Chambers, no additional port work
Pacaloy 1208X dual springs w/titanium retainers
FAST LSXR 102mm/ FAST 102mm TB
52 lb injectors/ ZL1 Camaro
Cam Motion billet core Hyd Roller Camshaft
248*/264*@ .050" with .694"/ .681" lift on a 112 + 4 LSA
Comp Cams short travel Hyd Roller lifters
3/8" x .120" wall pushrods
Crower Stainless Shaft mounted 1.8 ratio rocker arms
Rollmaster double roller timing set
Melling 10295 ported oil pump
Moroso 21150 F-Body Aluminum oil pan
ATI F-body damper
Did'nt really know what to expect for power, as always was hoping for more. But, I'm sure its gonna be fun for a street car and I can always add that big shot of juice when I feel the need.
They also made a couple of pulls with a Holley Hi-Ram intake w/90mm TB. The Hi-Ram made about 20 more peak HP, peaking @ 6800 rpm and carrying pretty flat until the 7000 rpm shutoff, but was down by 30 lb/ft tq across the entire range.
Here are the dyno charts and readouts for the FAST 102 intake, as a side note they used a 90mm DBW TB for the dyno runs since thay are set up for drive by wire. So, just wondering how much power is in running my 102 mm TB? In the print out you can see where there was a vacuum during a majority of the pull from 4600 rpm on up?
Last edited by floman; 10-12-2014 at 11:01 PM.
10-13-2014, 05:53 PM
#3
Yeah, I think it should pick up some. Looking at the MAP sensor reading from 4600 rpms and up it is showing below 100kPa and is indicating there is vacuum under wide open throttle. I assume maybe it could be the 90mm Throttle Body acting as a bottleneck?
Guess I'll find out once its in the car and get a good dyno & drivability tune done by either Geoff Skinner or Pat G.
Guess I'll find out once its in the car and get a good dyno & drivability tune done by either Geoff Skinner or Pat G.
