my car was dynoed on a mustang dyno
john, if i were you i'd check your braking system, i've heard of guys who had locked up rear brakes or e-brake that ruined their dyno time and made them put down really bad and confusing numbers... also, what transmission are you running?
I'm wondering what in the world the tuner is talking about. Low compression will allow much more timing. 12 degrees is pretty low. 8-8.5 to1 compression is pretty low. With aluminum heads, you should be able to run a LOT of timing. I personally think you have the wrong cam as well. And you SHOULD NOT be at 14-1 on a full throttle pull unless you feel like melting pistons. 42's are big enough, so I don't know why you have no fuel. Either a **** tune(possible seeing as what else was told to you), insufficient fuel supply, mass air not matched to injectors,etc...
Why did you get dished pistons anyway? Going forced induction?
Compression is one thing, but remember my combo is only 9.25:1...not high by any means, the stock 302s are around 9:1. I also have dished pistons and by heads are 60cc.
If you have AFR 185s then either something is jacked up with your tune, or my heads must be BAMF'ers because i find it impossible to believe that ported iron heads could flow as well as those AFR's.
I think one big thing holding you back is that cam. You only have .499 lift, that's not gonna make a ton of top end especially on a 360ci engine with AFR 185s. What's the duration look like? In fact what are cam specs altogether? 360ci and nice heads need a healthy duration and a good amount of lift to make good power, especially with that Trick Flow R intake. You've got the cubes and heads and intake, but not enough cam IMO.
Speaking of the cam...being a flat tappet, was it broke in correctly? You can't just stick it in and run it...if you do without proper break in you'll risk wearing off the lobes.
If you have AFR 185s then either something is jacked up with your tune, or my heads must be BAMF'ers because i find it impossible to believe that ported iron heads could flow as well as those AFR's.
I think one big thing holding you back is that cam. You only have .499 lift, that's not gonna make a ton of top end especially on a 360ci engine with AFR 185s. What's the duration look like? In fact what are cam specs altogether? 360ci and nice heads need a healthy duration and a good amount of lift to make good power, especially with that Trick Flow R intake. You've got the cubes and heads and intake, but not enough cam IMO.
Speaking of the cam...being a flat tappet, was it broke in correctly? You can't just stick it in and run it...if you do without proper break in you'll risk wearing off the lobes.
my motor is a stock bottom end 302, i have the trickflow twisted wedges that are milled down to 58CC combustion chambers to get my compression close to 10.5:1, they also have a bowl blend Jay Allen did to them himself
i agree with 85_SS on this one, when you said you had a .499 lift cam it was a major red flag... you have the cubic inches and the flow potential with the AFR 185s to make some serious power, but your cam is mismatched... if i were you i'd get in touch with one of the custom cam grinders and tell him your entire setup, you won't be disappointed, jay allen can get you a cam for around $300 that will make your combo perform at it's peak potential
That cam is super small for that combo.....weak lift.....weak duration, I would call up some cam companies or have one custom ground for your combo. And for compression, generally speaking 2ccs will get you .1 compression. Having an unknown compression ratio it's hard to figure things out too though...for all you know you could have 7.5 or 8:1 compression
Well, looking at your dyno pull, you are not running at 14 to 1. From what you can see of it, it looks ok. Maybe you are running ridiculously low compression and that's causing the problem, but even at 9 to 1, you should be able to run a lot more timing than 12 degrees. Do you happen to know what the total timing is? And as I also said, i too think you have the wrong cam. My cam I'm putting in my 302/306 is a lot bigger than that. It is a blower cam, but still..
Sounds about right to me for that cam and low compression. I wouldn't even put that cam in a mild 302. You should be looking for something closer to .600" lift. Unless you're planning on going with boost, compression is basically free hp. There is pretty much no drawbacks to running up to 10.5:1 compression, other than putting 93 octane in it. I think a lot of people would be surprised how much of a difference compression will make.
The tune worries me as well. I really hope it's not 14:1 at wide open.
The tune worries me as well. I really hope it's not 14:1 at wide open.