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Either way, the hp and tq increases are awesome. Looking at my dyno graph, I notice that it made peak hp at just over 10 psi @ 5050 rpm's, and then misfired, but at just over 5100 rpm's it was making 11 psi. I heard that the benefit of the power pipe isn't really seen until 10 psi and can increase boost by 4 psi. Shouldn't the 5.0 stop making power somewhere around 5700 rpm's? If that is true, might I not see around 14 psi at red line? If it made 380 hp at 10 psi at about 5050 rpm's, and it is making around 16 hp per 1 psi boost, I think it is safe to say it would easily be over 400 rwhp before it stopped making power at higher rpm's...
 
Yes, you will be easily over 400 hp. On this car here at 5800 rpm with my home made power pipe and the stock crank & 3.33" blower pulley I made about 12-13 psi of boost! So you should be right around there somewhere 13-14 psi. If my old stock GT 5.0 could make 425hp to the wheels then there's no reason why your Cobra motor can't do as much or better!
 
The impeller will hit its maximum rpm and it won't provide anymore boost (it won't pull all the way to say 10,000rpm). I think 16psi is way too high for your motor. Sure it can be safely tuned there but those head bolts would probably flex and you'd be changing head gaskets. I know this because I did it. I changed to a small 12psi pulley with AFM powerpipe and the boost spiked high. I saw the boost needle exceed 15psi on the gauge quickly so I got off of the throttle but when I looked in the rearview mirror nothing but white smoke.

I'd upgrade the ignition and I'd head back for another dyno tune.
 
Also I can see on the dyno graph that you went a little rich on the A/F toward the end. Leaning that out some could be worth more HP as well. I thought those A/F lines are suppose to be nice and flat around 12.5:1
 
The impeller will hit its maximum rpm and it won't provide anymore boost (it won't pull all the way to say 10,000rpm). I think 16psi is way too high for your motor. Sure it can be safely tuned there but those head bolts would probably flex and you'd be changing head gaskets. I know this because I did it. I changed to a small 12psi pulley with AFM powerpipe and the boost spiked high. I saw the boost needle exceed 15psi on the gauge quickly so I got off of the throttle but when I looked in the rearview mirror nothing but white smoke.

I'd upgrade the ignition and I'd head back for another dyno tune.


My car routinely sees 15+ psi when I floor it but my tune is so conservative it's pulling a lot of timing at that point. I suppose that keeps the head gaskets in place! I've never blown a head gasket on a 5.0 (knock on wood). I want to run meth but I think I'll be also running a A2A setup as well, reason being it will always be there even if the meth system malfunctions and it will bring my boost numbers back down to a manageable level. I just hate having all those pipes running everywhere!
 
The impeller will hit its maximum rpm and it won't provide anymore boost.

Isn't that the benefit of the power pipe, that it will result in additional psi while spinning the blower at the same speed? My pulley is only supposed to be good for 8-10 psi but at 5100 it was at 11 psi and climbing. That's why I was thinking that it could hit 14 psi at 5700 or so.

I probably won't do another dyno tune for a while. It's $180 an hour to get on it but he will make changes to the tune and tweak it for free. He does have a dyno day coming up on a saturday where you can get two dyno runs for $50. I will probably head out there for that. Ultimately, I want to be able to data log and tune it myself.
 
Installed the MSD today. I mounted it underneath the windshield washer pump with a couple of L-brackets and some self-tapping screws. Unless you know what you are looking for, you can't even tell it is on there.
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Why did you go with the 6al and not the 6al2?

That is what the tuner recommended. Plus, I was able to buy it brand new for under $200.

Are you not worried about it getting wet?

Not at all. The car is only driven when the weather is nice and sits in the garage the rest of the time. If it was my daily driver then I would have been a little more concerned about it.