Mysterious Missing Power
Thread Starter
5th Gear Member
Joined: Sep 2006
Posts: 4,039
From: CA
Mysterious Missing Power
Hey guys,
Been to the dyno and the track a couple times and it is certain....I am making about 40-50rwhp less than I should be. I am full bolt-ons except for the mid-pipe and set of blower cams and am only putting down 220rwhp. It's not the tuning. I have had it tuned several times starting from scratch all times and it doesn't make a difference. It puts down 210rwhp with a stock tune and dialing the A/F and timing helps a bit in the mid-range, but the top end is just not there. Here is a pic of my dyno graph. The only thing I can think of is clogged cats unless I have basically zero compression. I will be swapping out my mid-pipe tomorrow to see if that is the culprit.
Anyone have any other ideas that could cause such a significant power loss?
Been to the dyno and the track a couple times and it is certain....I am making about 40-50rwhp less than I should be. I am full bolt-ons except for the mid-pipe and set of blower cams and am only putting down 220rwhp. It's not the tuning. I have had it tuned several times starting from scratch all times and it doesn't make a difference. It puts down 210rwhp with a stock tune and dialing the A/F and timing helps a bit in the mid-range, but the top end is just not there. Here is a pic of my dyno graph. The only thing I can think of is clogged cats unless I have basically zero compression. I will be swapping out my mid-pipe tomorrow to see if that is the culprit.
Anyone have any other ideas that could cause such a significant power loss?
Last edited by tbirdscwd; Mar 29, 2010 at 10:44 PM. Reason: title spelling
Thread Starter
5th Gear Member
Joined: Sep 2006
Posts: 4,039
From: CA
Yes, normally they read lower than dynojets do. But not this much lower. I'm also running 13.9s @ 100mph with 1.8x 60fts. The power isn't there. I should be seeing this same power stock (maybe even more at some rpms)......not with basically full bolt-ons and cams.
1st Gear Member
Joined: Feb 2010
Posts: 64
From: Indiana
yeah something is wrong, my automatic car made 227/267 with just intake and exhaust before i finished my bolt ons. does the car not feel like it runs right? i mean missing out on 50 to the wheels you should notice it in how it drives.
Thread Starter
5th Gear Member
Joined: Sep 2006
Posts: 4,039
From: CA
It doesn't have any drivabilty issues such as misfires or anything. It just isn't putting
down much power at WOT. This is why it seems to me that it is an external issue. If I am getting all cyls firing with the right timing and AF, I can't think of anything else it can be.
down much power at WOT. This is why it seems to me that it is an external issue. If I am getting all cyls firing with the right timing and AF, I can't think of anything else it can be.
Thread Starter
5th Gear Member
Joined: Sep 2006
Posts: 4,039
From: CA
Well I verified with a few engine builders that there are two distinct possibilities.....It's most likely either of two things that could cause this much of a power loss. Either my cam timing is somehow off, or my cats are clogged. Since my power is basically capped at 220rwhp, there has to be a significant flow restriction. I sure as hell hope my cam timing isn't somehow off by skipping a tooth or something on my 1 1/2 year old built longblock!!!
I verified with MPH that my motor should be seeing right around 280rwhp N/A (dynojet) with my current mods. I will be swapping out the mid-pipe tomorrow and will know then whether or not I need to start taking the valve/timing covers off and get the cam timing figured out.
I verified with MPH that my motor should be seeing right around 280rwhp N/A (dynojet) with my current mods. I will be swapping out the mid-pipe tomorrow and will know then whether or not I need to start taking the valve/timing covers off and get the cam timing figured out.