LS3 Low dyno numbers, head scratching
08-10-2018 | 01:55 AM
#1
Thread Starter
Teching In
Joined: Dec 2015
Posts: 43
Likes: 1
LS3 Low dyno numbers, head scratching 
hi all,
I’m at the tail end of a LS3 conversion into a Mazda RX8.
I rebuilt the LS3 with
new SRP Pistons and ring
Cam 224/230 114 LSA Cam set mark to mark
New stock timing gear and chain
LS7 Lifters
New chromly pushrods (cant remember the size but I specd them at the time)
Long Tube Headers
refreshed heads with LS9 gaskets
All new seals
etc
It is running a ECU Master EMU black with wasted spark setup.
It start up fine, straight away with good oil pressure which was a relief!
It has run in on the dyno properly for a couple of hours,
the power run for its final tune though ended up with only 355 whp and 390wtq.
too me this is very low for a Cammed LS3 with headers.
The shop has checked the timing and also the pushrods length because I thought I had screwed it up. This all seems normal.
Where do we look next for those lost HP!!
08-10-2018 | 05:50 AM
#2
is this through an auto or manual? what type of rear? what type of dyno and whats the overall compression ratio, 10.7:1? do you have a graph of the dyno? what gear and RPM did it go up to? need these types of info lol
08-10-2018 | 12:32 PM
#3
11 Second Club
Joined: Mar 2012
Posts: 1,541
Likes: 15
From: South Florida
As the above the more details the better. Like stated was it in the 1:1 gear? What rpm at hp & tq peak numbers? Graph. Don't think that intake tube is helping power up top but? Also the exhaust from headers back. Is it a small single pipe?
08-14-2018 | 04:59 PM
#4
