dyno runs on the 408
dyno runs on the 408 finally got around to it today. was done at norris motorsports.
review of setup
408
11.5:1 compression
SLP lid
vinci ported MAF ends
NX 85mm TB
NX intake
ASP under drive pulley
42# SVO injectors
2.02/1.60 ported 4.8L heads
232/240 .551/.551 (1.7 ratio) 117 LSA
crane 1.8 shaft rockers (brings lift to .589/.589)
dynatech 1 3/4 stepped 1 7/8 headers w/3" collectors
bassani tru-duals 2.5" w/x-pipe
yank py3400 converter
3.73 gears
275/50-15 nitto DRs
250 NX NXL DP nitrous
this run was on motor converter unlocked
this run was on motor, converter locked 21* timing
same run with 26* timing
this run is with the 250 shot. tires spun on the dyno and didn't hook until almost 5500 rpms
here's the same run using mph, so you can get a little better view of the run
review of setup
408
11.5:1 compression
SLP lid
vinci ported MAF ends
NX 85mm TB
NX intake
ASP under drive pulley
42# SVO injectors
2.02/1.60 ported 4.8L heads
232/240 .551/.551 (1.7 ratio) 117 LSA
crane 1.8 shaft rockers (brings lift to .589/.589)
dynatech 1 3/4 stepped 1 7/8 headers w/3" collectors
bassani tru-duals 2.5" w/x-pipe
yank py3400 converter
3.73 gears
275/50-15 nitto DRs
250 NX NXL DP nitrous
this run was on motor converter unlocked
this run was on motor, converter locked 21* timing
same run with 26* timing
this run is with the 250 shot. tires spun on the dyno and didn't hook until almost 5500 rpms
here's the same run using mph, so you can get a little better view of the run
Last edited by mrr23; Nov 14, 2007 at 11:44 AM.
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so you are running a 408 with ported 4.8ltr heads..... do you have some crazy aggressive port job on them or is it just over hyped that 4.8/5.3ltr heads are just to small for anything over 383ci???
here's the timeslips
motor was 11.84 @ 117 nitrous was 11.189 @ 128.24
it sounds slow by looking at those numbers
if you look at the best NA vs nitrous run, you'll see the 330' mark was only .1 lower and the 60ft was about the same. traction limiting, i didn't hit the nitrous until almost 200' out. so, there's plenty more in it. it's a solid low/mid 10 second car back then. now, with the 250, who knows? the car is a full weight, nothing removed, full on drive it everday car.
i'm a little disappointed with the NA numbers. but hey, how many 650+ rwhp daily driven cars are there?
the exhaust side is on the low side versus most other heads. i'm in the air about how much they are restricting the motor because of the exhaust port. these heads used to be on the wife's car. so, i used them instead of buying AFR heads. something i'm looking into for next year.
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Joined: Feb 2005
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From: Gateway International Raceway
For your mods I think you make good power. I think your cam is a bit on the mild side for a 408 and some AFR heads would benefit you in my opinion. Autos are not dyno monsters...but they are great at the track with a nice stall.
Your compression is just right for a bigger cam...244/248
or something like that ( I am no expert), your exhaust set up looks awesome...(I should have true duals). What is it like with that converter and those gears 
? It seems like 1st gear would be useless due to tire spin...you get decent traction?
Keep the updates coming.
Your compression is just right for a bigger cam...244/248
or something like that ( I am no expert), your exhaust set up looks awesome...(I should have true duals). What is it like with that converter and those gears ? It seems like 1st gear would be useless due to tire spin...you get decent traction? Keep the updates coming.
