7 port ignition mapping issue.
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I'll get a picture in the morning.

Class C 3rd Place Avon 2011 14.18 @101mph

wow so thats already a .75 '' total length plug .


heres joes counterbored plug location




looks a lot better , ithink that was a 5mm deep c.b. its in his thread . that is a steel head though i think , so maybe the same on waterway design or maybe not !

Edited by robert on 6th Sep, 2012.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

That looks alot better, it would also give me more clearence with the TB's.

Class C 3rd Place Avon 2011 14.18 @101mph

Hi

Looking at that pic i have two concerns:

what will the exposted threads do for preignition?

what will the heat range be when the plug is this far in ?

So I did some searching and I have found a reference to plug depth and timing:

''When adding a .064 washer the CCs of the chamber were increased 0.4%. I will let you folks run your sims to figure out what happens. It is a small number, sure, but in something critical like a Pro Stock car it's not so little. The only good thing I could find is that a spacer can be used to effectively retard a particular cylinder.

One other downside to the washer thing is that you leave cylinder head female plug threads exposed as a potential hot spot. ''


If you are getting machining done i would consider going to 10 mm plugs if they fit better ( better contact Piece first if there is enough metal to do so first).

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

Class C 3rd Place Avon 2011 14.18 @101mph

If you have it on a flow bench try to get pitot readings from both sides as well.

Oh and do take a few pics when you take the valves out of the bowls to see how they look.

good luck.

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

Inlet Valves and port look like new, no sign of any carbon. I guess no reversal?

Pilot Reading? Ill be lucky to get any bench flow time, its a friend of a friend, it took several weeks last time.

Edited by alaskanow0 on 6th Sep, 2012.

Class C 3rd Place Avon 2011 14.18 @101mph

agh. well no worries. My guess (guess!) is that the lengths are pretty okay . only the port is a tad big, but unless you can spend serious time working on the head that it's just what is .

you still have good power figures even though I think once you figure the timing weirdness out there is more in there.

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

did you get a manage to get some headway? just curious

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

I never got to the bottom of this. Now sold the Webcon head and bought the Specialist Components 7 port. Keeping the same dta management and loom, so we will see if the issues was head specific or management.

However in conclusion

Cam timing was correct at 106deg
TDC was perfect
Same engine ran perfectly fine with 30deg max advance with 5 port and SC wet manifold and typhoon ECU.

Just one annoying thought remains - if crank sensor wiring was the wrong way around in the dta loom. DTA said it would still run, but would cause issues. I suspect this because the crank scope facility was always random. I never saved it to compare to the DTA manual.

I'll keep you updated, once new head is installed.

Edited by alaskanow0 on 28th Dec, 2012.

Class C 3rd Place Avon 2011 14.18 @101mph

The crank scope works. If you arent getting a sensible reading, it's because there is a problem with your crank signal.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will