Six pack bog

[BSB67]

I'm pretty sure Fizz has a set of closed chamber aluminum Stealth's on this build based on the ZFR6F-11 plug he is using. That's the recommended NGK plug for the Stealth heads. Heat range is 6 which is correct for a pump gas build, from my experience. 
Sure

The 172psi dynamic reaing is pump gas friendly....if it pings the problem is either ignition or fuel delivery related.
Sure

With regards to total timing ; I've had several similar street builds using closed chamber aluminum heads and all have made their best power number with 34-35* total timing. The latest is a 426 street wedge with 9.8:1 compression and a mild hyd flat tappet Crane grind. That combo made best power at 34* total timing and the numbers went backwards as timing was increased. 
I've done this long enough, and have seen enough to know to not presume any number is right or wrong regarding total timing until I have car specific data.  I have no idea what the right total timing will be, and it seems logical to try several to just to see what happens to the ping.  I promise, we will learn something.  There is only one way to determine the best total timing

I would get the timing curve dialed in before fooling around with the jetting....but that's just me. 
The car idled better before, he enriched the carbs.  Then it ran worse. I'm not sure why you would go to the timing curve next.

My rule of thumb has allways been ignition first....then fuel delivery. 
This makes good sense initially when the ignition is in left field, which in not uncommon.  But the reality is you need to go back and forth between the two as you step through the process.



Ron
[/quote]

[c00nhunterjoe]

All great points.... but we are still overlooking an erratic vaccum needle at idle.

[fizz]

Been out on the road last few days. I don't know exactly which heads I have other than they are stealths, supposed to be ported, engine builder isn't talking. Any way I can tell for sure? Went with those spark plugs on a recommendation because it has a pinging problem since I got it. Since I know where it wants its initial timing, and I know it is pinging where it is at now, this has been constant, I think I might as well adjust distributer to get rid of this problem by dialing back total timing. It initially had an erratic needle, that I got rid of by adjusting the valves, then came back with the PCV valve, I will check that also. It is easy to adjust that for lower idle vacuum. I got the piston part # DRP50  52421 22663 when I pulled the oil pan to fix leaks which with ported stealth heads comes to 9.8 compression if I remember correctly. I will also redo my initial timing checks with a different timing light and vacuum guage this weekend after I curve the distributer. Jet plates aren't here yet, so that will have to wait for next weekend. SO, for this weekend,1  curve the dizzy, 2  disable pcv valve and reset timing and idle adjustments,  3 re adjust pcv valve, road test for timing.

[c00nhunterjoe]

Ok, so valve adjustment stopped the needle. Good. Now just cap the pcv temporary to make sure there is no problem, then move on.

[fizz]

YIPPIE. Finally runs nice  timing at 24 initial, 34 total, orange springs from summit tuning kit, 3/8 turns on secondary idle mixture screws, long yellow springs in vacuum pods, 12 by at idle, no ping anywhere on 91 gas, no octane booster except what I had at 1/4 tank when I filled. Now I will fool with secondary jetting when plates get here and try bumping total timing up a little

[BSB67]

YIPPIE. Finally runs nice  timing at 24 initial, 34 total, orange springs from summit tuning kit, 3/8 turns on secondary idle mixture screws, long yellow springs in vacuum pods, 12 by at idle, no ping anywhere on 91 gas, no octane booster except what I had at 1/4 tank when I filled. Now I will fool with secondary jetting when plates get here and try bumping total timing up a little

Good, glad to hear it.

Not to be Mr. Negativity, but it is really not clear to me how you will determine if any outboard carb jets changes are either helping, or hurting.  Just like total timing, there is only one way to truly get these dialed in.  Okay, maybe two.

[b5blue]

YIPPIE. Finally runs nice  timing at 24 initial, 34 total, orange springs from summit tuning kit, 3/8 turns on secondary idle mixture screws, long yellow springs in vacuum pods, 12 by at idle, no ping anywhere on 91 gas, no octane booster except what I had at 1/4 tank when I filled. Now I will fool with secondary jetting when plates get here and try bumping total timing up a little

Good to hear! 

[firefighter3931]

YIPPIE. Finally runs nice  timing at 24 initial, 34 total, orange springs from summit tuning kit, 3/8 turns on secondary idle mixture screws, long yellow springs in vacuum pods, 12 by at idle, no ping anywhere on 91 gas, no octane booster except what I had at 1/4 tank when I filled. Now I will fool with secondary jetting when plates get here and try bumping total timing up a little

Good, glad to hear it.

Not to be Mr. Negativity, but it is really not clear to me how you will determine if any outboard carb jets changes are either helping, or hurting.  Just like total timing, there is only one way to truly get these dialed in.  Okay, maybe two.

I agree with Russ....it might need another trip to the chassis dyno to see what's up. 

You would be able to increase the timing slightly and see what effect that has on power and also monitor AFR's and adjust jetting accordingly. 

Good work ! 


Ron

[BSB67]

YIPPIE. Finally runs nice  timing at 24 initial, 34 total, orange springs from summit tuning kit, 3/8 turns on secondary idle mixture screws, long yellow springs in vacuum pods, 12 by at idle, no ping anywhere on 91 gas, no octane booster except what I had at 1/4 tank when I filled. Now I will fool with secondary jetting when plates get here and try bumping total timing up a little

Good, glad to hear it.

Not to be Mr. Negativity, but it is really not clear to me how you will determine if any outboard carb jets changes are either helping, or hurting.  Just like total timing, there is only one way to truly get these dialed in.  Okay, maybe two.

I agree with Russ....it might need another trip to the chassis dyno to see what's up. 

You would be able to increase the timing slightly and see what effect that has on power and also monitor AFR's and adjust jetting accordingly. 

Good work ! 


Ron

Exactly.

[fizz]

I agree, I would have to find a shop that will actually do it or let me do it on their dyno, not to good of luck so far. It had been on an engine dyno then a chassis dyno. Both guys told me it was good to go. I don't even bring up money when I talk to them, so , any minnesota reccomendations?

[BSB67]

You could always go to the track.

[fizz]

Probobly way I will go. Brainerd is about an hour away and they have test and tune nights

[Tom Q]

I am the caretaker of the six pak tuning guide. I compiled the info, copy edited it and added my own information but I did not write it.  It is an ever - changing reference document as I read the boards to provide better information. I doubt you will get to see the latest rev.   I provide technical support for a very technical product so technical writing and attention to detail is a requirement for effective service and information so technical documents are easy for me to write.
 
The biggest mistake everyone makes is the refusal to put the carbs in the proper baseline set up before trying to cure bog issues pinging etc. I am not sure if the OP has read the guide &  baselined his carbs, but the tuning issue has been resolved and I learned some more tuning info for the guide.  thank you

Now i am not sure what to make of the comment referring to the guide  as "The one that tells you that gasoline is flammable" but my first impression is not good. We live in times where most have no good sense about life and need to be told everything. Now you all know who Tom Hoover is...RIP Tom.  If you don't look it up. When these cars  were just used cars in the 80s the NEHOA put on 2 meets per year & Tom was invited to one back then and he attended many there after. He would hold us spell bound for hours in tech seminars. Each and every time he would close the session by stopping with a big pause and tell us " ALWAYS be respectful of gasoline as it will burn and kill you." If that little disclaimer was not on the document I am sure there at least one person out there that would hurt themselves trying to tune a six pak and want to sue me because I did not tell them that...doh! 
So if you want to reference something that works and is "popular"...I don't think it's that popular based on the posts about tuning...please use better words than referring to it as "The one that tells you that gasoline is flammable".

[BSB67]

It is popular because the people that use it don't know any better.  And there are a lot of those people.
The people that do know better, don't use it.
You like to mention Tom's name frequently.  That seems important to you to mention.  I've met him too, as most long in the tooth enthusiasts have.

I get that because you are the caretaker, you are going to defend the document.  Myself and other might be a little more tolerant of the document's inaccuracies if the caretaker shared his personal history and experience with the six pack that support the claims and directives in the document and that supports himself and the document as truly a self made authority on the subject.

It reads like a poor compilation of some good, and not so good information that is not is not delivered in proper context or with appropriate qualifications.  Kinda like getting apple pie recipe from 12 people and using a little bit from each one.  That does not make it a good recipe or pie.

[b5blue]

I drove my Charger daily for 6 years, my "work car". The 6BBL never missed a beat. Later after the 440 rebuild another 7 years, again nothing bad. You are on the path and learning so take your time and have fun! It's a hoot as your starting to see. 

[fizz]

B5, even though I realize I started this like a cub bear with boxing gloves, I learn a little and my car runs a little better every time I work on it now. I don't expect John Force to be calling me anytime soon, unless, maybe, he wants to build a racetrack, I could do that.

[fizz]

Crazy part is, I am doing better than the guys I paid to do it. And they are players in the Minneapolis/st paul area, Magazine article king of guys. WTF

[b5blue]

Not uncommon, your 100% invested in getting it right!  (Unlike hired shops with no time for the learning curve.)

[70sixpkrt]

Reply with quoteQuote 


YIPPIE. Finally runs nice  timing at 24 initial, 34 total, orange springs from summit tuning kit, 3/8 turns on secondary idle mixture screws, long yellow springs in vacuum pods, 12 by at idle, no ping anywhere on 91 gas, no octane booster except what I had at 1/4 tank when I filled. Now I will fool with secondary jetting when plates get here and try bumping total timing up a little

Glad that it's running good. What do you mean by orange springs?

[myk]

Reply with quoteQuote 


YIPPIE. Finally runs nice  timing at 24 initial, 34 total, orange springs from summit tuning kit, 3/8 turns on secondary idle mixture screws, long yellow springs in vacuum pods, 12 by at idle, no ping anywhere on 91 gas, no octane booster except what I had at 1/4 tank when I filled. Now I will fool with secondary jetting when plates get here and try bumping total timing up a little

Glad that it's running good. What do you mean by orange springs?

He's referring to the springs you attach to the advance plates in the distributor.   Different Springs will either bring your timing in sooner, or later...

[70sixpkrt]

Got it. Thanks. I'm running a MSD distributor and have blue or silver springs.

[fizz]

Yup, firecore sold me a set of springs and advance keys that summit made up. Had a bunch of. Timing curves mapped out. The 2 orange springs came in at 1100 rpm and gave me 10 degrees advance at 2600, thereabouts

[fizz]

10 degrees additional I meam

[ottawamerc]

Just wondering, have you changed your fuel squirt er nozzles on the center carb? On my build and with the A/F gauge I noticed that it would lean way out when I would punch it. I had to go up 2-3 sizes on the jet to keep it on track when accelerating to WOT.

Scott

[fizz]

Not yet, havn't got track time yet