Cylinder Head Shootout

Yes,

CC volume is as follows. All the chambers where stock. CC rise is from surfacing nothing more. Again no need to change the tune. Car is running on the datalog 22 total on 104. End of discussion.

PPP: 82.4cc

Mopar: 82.4cc

HHP: 79cc

PR&D: 79.6cc

 

your running 22* of timing on 104 octane?I would think it could use a tad more.Did you dyno the previous using 104 octane?what was the timing at?

 

All the dyno's are done on the same tank of gas and the same tune. This tune again..... got him to run 11.97. Trust me when I say you can not run more than 24 degrees on these cars. The combustion chambers in these heads are very efficient. Not like a chevy or a ford where you can run 30+.

 

Not so much, but it's your test.

 

You can't be serious? I have 30 degrees in my N/A stock longblock 93 octane tune from B&G as does everyone else with a Dave Kasper N/A tune. Even the stock tune has 24 degrees @ WOT.
Is this the 392 (running 11.97) you're talking about?

 

Again we are agreed...... 22* on 104 octane is going to do nothing but hurt power.

 

Hey Yesterdays dyno was number 161 for me, The last 60 or so are after CMR was released. We started out running 27* and tha car hated it. We didnt start making power tell we pull some out. The car likes it a 22-24* total. we could argue this all day but Im telling you from hands on, Ive seen it myself. I ran 11.97 on 22-24* And were not on a search for peak HP. Only the difference between them.

 

Cris.....what fuel were you running last time when the car liked 22-24?It sure as hell wasn't 104 octane.

 

yeah it was..

 

What's the static C/R of your 392?

Again this is not a knock, but running 11.97 (which some stockers have eclipsed) isn't proving much.

 

Absolutely, running 104 or even 100 octane with stock compression is going to hurt power period.

 

9.5:1

 

Guys, lets not forget that these are 5.7L heads. I personally haven't seen a 5.7 head off the car, so I don't know the differences - but we seem to be comparing timing between a 5.7L based motor and 6.1L. Maybe there is something different in the 5.7 that limits the timing before it knocks.

 

Planning on forced induction?

 

Uh ,no difference I am aware of.With 104 on that timing and compression it will slow the burn enough that the motor will actually lose power.

 

If your running a B&G tune prior to the CMR release then you know he "commanded" 30+ degrees of timing and your car would pull +6 degrees or more out. Why would it do that. If you have a dyno and you have CMR for these Hemi's then you would now how much timing a "particular" car likes. In Chris's case and this 392 it does not like a lot of timing. In reference to his cr ratio. Ask Indy they developed the kit and deemed it necessary to run flat top pistons instead of a factory dome style.

 

Optimum timing is definitely 22-24 degrees of timing. They are right on the mark. I have 107 tunes in my database, they definitely do not like allot of timing.

 

we run about the same amount of timing and run 110 at the track. So now you have the fastest NA SRT car in the country and the fastest NA 5.7 car in the country both running less than 24 degrees of timing. What does that tell you?

 

On 104 octane?

 

Well my 5.7 cmr tune with BP 93 was getting 26 at WOT

Ill find out tomorrow where its as with the heads and cam.

-R