still with pinging

[Nacho-RT74]

trying vacuum unplugged, initial timming around 12° ( its jumpy )... mopar recurve kit with pink and orange springs ( as far I remember ), limited to 20°. CR around 10.3:1 on ported and bigger valves iron heads.

that proves the vacuum advances is not the guilty

95 octane gas

at this moment I'm in vacation with my charger, so at sea level ( in a caribbean island in fact ). when cold ( maybe first 20 min ) the car goes nice without pinging even at WOT )... but after that time, maybe over 2800, I get pinging at WOT. Sometimes without go WOT, but going fast

just rest... enrich the mix somewhere ( acc pump ? second air valve vent ? TQ carb ) ?

try some octane booster ?

diff spark plug heat range ? I'm at this moment with XR5s NGKs ( V power )

[Budnicks]

Camshaft could be too far advanced making that 12* more like 16*-18*, I have my current 479ci with CEI Chrome ECU box & Blaster 2 coil, initial timing is 16* & total is 36* comes in about 3000rpm, with the vacuum advance hooked up & working properly, a heavy & light spring, I don't remember the colors, I also have CEI distributor & an adjustable vacuum advance unit & it's turned in almost all the way, plugs are NGK 5 w/ext. tip equivalent, I have Edelbrock RPM Aluminum ported heads 84cc chambers, it has over 10:1 compression & a old avert. 280*/0.550" {ball park}, custom Crane Hyd. roller camshaft, lifters & 1.6:1 Super Gold Rockers, set @ 0* when installed & degreed, the cam already had 2* advance ground into it.... I can run on even crappy Calif. 91 oct. unleaded pump gas "all day, with 190*-200* water temp" {aluminum rad., water pump & electric fans} & no pinging ever... How hot is the engine getting ??, How big of bore was it ??, are you sure the TQ Carb is tuned correctly... I think if you timing mark is bouncing, that is a sign of a loose/sloppy timing chain or worn-out or bent distributor shaft or bad shaft bushing or something along those lines...  I wouldn't think with 95 oct. you shouldn't have the issues your talking about unless the #'s are way off or something else is wrong, allot of sharp edges on the piston tops or in the comustion chamber, creating hot spots possibly detonation/pining, or with your ignition set up, magnetic pick-up or reluctor, advance curve, cam timing &/or Carb tuning possibly, or just really crappy gas... That's Just my thoughts...

[Nacho-RT74]

I'm ready to go to bed now, but posting more about what I have:

everything new on engine build. 282HDP crower cam, summit roller timming chain kit, mounted at 0.

I softened all sharpy edges I found around ( pistons and heads ).

Block sleeved, 0.020" bored  ( stroked 400 3.75" )

never degreed the assembly , just biuld it up straight up to 0 on everything

[Brass]

Your cam may be retarded then. It should be 108* centerline.  I don't know if that would cause the pinging though. 

[BSB67]

Do a cylinder pressure test and report back.

If you have more low end power than you want or need, you can retard the cam timing to help.

And yes, a cooler plug will help and could eliminate your problem if you are just on the edge.

[Dmichels]

IMHO your 10.3 to 1 CR is too high You can get away with a higher CR with aluminum heads but not with iron. Todays gas even "high" test is crap compared to the gas from the late 60's When I built my 440 15 years ago I went with 9.5 to 1 CR Pulls strong no pinging on 91 octane I did not have to retard the timing at all I forget what it is set at. You are beter off with a lower CR so you can still have full advance. Visit the local airport and get some 100 or so octane gas and it should run like a champ. If thats the case see if you could use a thicker head gasket if avalbele to lower your CR
Dave

[Nacho-RT74]

I'm using already composite gasket.

I never could get a correct quench due a bad block decking job at machine shop, getting rear pistons around 0.005" over the deck, and fronts around 0.010" below the deck, so CR is between 10.2 and 10.4 to 1, Planning to square everything in a soon future

[Nacho-RT74]

in case that I need to try a diff spark plug heat range... is the XR4 or XR6 the one needed ?


these spark plugs are not available down here to my car, so a Champion equivalent would be nice. I have RJ12YC around to try, but I think those are the same heat range than the XR5s, right ?... so maybe J14s ? or J10s ? No Rs locally to my car, so have to make the test with non-resistors ones.

[Budnicks]

I'm using already composite gasket.

I never could get a correct quench due a bad block decking job at machine shop, getting rear pistons around 0.005" over the deck, and fronts around 0.010" below the deck, so CR is between 10.2 and 10.4 to 1, Planning to square everything in a soon future

That's not good... That could be a big part of the problem right there... inconsistent compression & bad spark timing probably, the rear cylinders are probably the ones causing the detonations/pinging problems...  Anything you do will be just a band-aid until it's fixed properly...   You can get the block squared properly "hopefully" & then maybe Enlarge & CC you combustion Chambers to drop the compression some &/or go to some 0.050-0.060" Hussie ot Titan Copper head gaskets, to drop the compression back to where it needs to be, for you specific, engine, compression, piston, cylinder head, head gasket, camshaft, valve clearance combo....

[BSB67]

in case that I need to try a diff spark plug heat range... is the XR4 or XR6 the one needed ?


these spark plugs are not available down here to my car, so a Champion equivalent would be nice. I have RJ12YC around to try, but I think those are the same heat range than the XR5s, right ?... so maybe J14s ? or J10s ? No Rs locally to my car, so have to make the test with non-resistors ones.

Your plugs are too hot.

Order yourself the NGK R5670-7 (Champion J63Y equilivant), Stock No.2891.  This plug might be one step too cold, but start here.  The next hotter plug is the -6, or the Accel 134.


I was in a pinch once and bought some J12Ys (same as the the XR-5) for my 10.3 CR motor.  It would rattle terribly accelerating at half throttle.  The -7s nearly eliminated it.

[Nacho-RT74]

Budnicks, I know that's not good and got ANGRY when assemblied discovered that, because I was working on my build trying to get quench, HOWEVER still with the bad decking job, the rears are still on quench ratio with composite headgaskets, the fronts are the ones not. I'd think more in fronts getting pinging.

pistons are KB215s, and heads are 452s, polished chamber, so got some deepness extra when polishing ( casting imperfection is very deep )

One note extra. Yesterday found on a gas station an STP octane booster ( not easy to find locally and REALLY EXPENSIVE, I can fill the tank around 15 times with the price of the booster ), got a bottle and added to test, and pinging went away... if I had still some pinging, I didn't noticed. I noticed some pinging initially, but maybe was because the octane booster was not still mixed ebough into the gas tank.



it was just a test but not an option.

Airplanes gas is not accesible.

BSB67... I remember you telling me about the NGKs 6 or 7 once, but once searching on NGK website, found for earliers higher compression 440s the XR4s stated like the ones to be used, so I had a doubt on that

[Budnicks]

Budnicks, I know that's not good and got ANGRY when assemblied discovered that, because I was working on my build trying to get quench, HOWEVER still with the bad decking job, the rears are still on quench ratio with composite headgaskets, the fronts are the ones not. I'd think more in fronts getting pinging.

pistons are KB215s, and heads are 452s, polished chamber, so got some deepness extra when polishing ( casting imperfection is very deep )

One note extra. Yesterday found on a gas station an STP octane booster ( not easy to find locally and REALLY EXPENSIVE, I can fill the tank around 15 times with the price of the booster ), got a bottle and added to test, and pinging went away... if I had still some pinging, I didn't noticed. I noticed some pinging initially, but maybe was because the octane booster was not still mixed ebough into the gas tank.



it was just a test but not an option.

Airplanes gas is not accesible.

BSB67... I remember you telling me about the NGKs 6 or 7 once, but once searching on NGK website, found for earliers higher compression 440s the XR4s stated like the ones to be used, so I had a doubt on that

I would try the colder plugs also

[Nacho-RT74]

Your plugs are too hot.

Order yourself the NGK R5670-7 (Champion J63Y equilivant), Stock No.2891.  This plug might be one step too cold, but start here.  The next hotter plug is the -6, or the Accel 134.

I have some questions...

one: are these you make mention V power ones ? or standard ?

two: there is some diff in performance using hotter or colder spark plugs ?

three: why earliers 440s ( 67/68/69... ) are in 4 heat range as the NGK website states beign those with higher CR ?

four: Is more less the same effect use a higher octane gas ( if available ) than a colder plug ? if so... why ?

five: what about iridium plugs ?

[BSB67]

I have some questions...

one: are these you make mention V power ones ? or standard ?  Yes, V-Power Racing

two: there is some diff in performance using hotter or colder spark plugs ?If you have detonation, yes.  Generally, a cooler plug is faster or the same.  Cooler will foul sooner

three: why earliers 440s ( 67/68/69... ) are in 4 heat range as the NGK website states beign those with higher CR ?I don't know what you are looking at.  The XR4 is a replacement for a J14Y/J18Y.    Probably too hot for a 8.5:1 CR motor.

four: Is more less the same effect use a higher octane gas ( if available ) than a colder plug ? if so... why ?No.

five: what about iridium plugs ? I think you are loosing focus here.  You are probably on the verge of melting a piston, or breaking rings/lands.  Simply put a cooler plug in it.  It could fix your problem, maybe not.  You don't need to believe me on this, spend $25 and see for yourself.  There is no down side.

 

[b5blue]

Wiki has a section on "spark plug heat range" you can read to explain this. 
   Basically the tip of the plug is staying so hot it is igniting the fuel/air before spark when your under heavy load. The trick is to find the range that is cold enough to not ping but be hot enough not to foul out when idle/low speed. You have modified your engine and ignition so think, higher or hotter spark and compression may change heat characteristics of spark plugs from what you were using before.     

[Nacho-RT74]

three: why earliers 440s ( 67/68/69... ) are in 4 heat range as the NGK website states beign those with higher CR ?I don't know what you are looking at.  The XR4 is a replacement for a J14Y/J18Y.    Probably too hot for a 8.5:1 CR motor.

four: Is more less the same effect use a higher octane gas ( if available ) than a colder plug ? if so... why ?No.

five: what about iridium plugs ? I think you are loosing focus here.  You are probably on the verge of melting a piston, or breaking rings/lands.  Simply put a cooler plug in it.  It could fix your problem, maybe not.  You don't need to believe me on this, spend $25 and see for yourself.  There is no down side.

Three: Check on NGK website and search by automovile. Will find a 68 440 HiPo requires XR4, and these are higher compression than my 74 400 in stock form, being recomended XR5 for them


four: well I was asking because If I made to allmost ( if not completelly ) eliminate the pinging on my car with the octane booster, I don't know how a cooler plug will make the same... Unless there is two ways to get the same effect. I can understand why a coller plug will fix, and also allmost understand why the octane booster also makes the same ( like using a higher octane gas ), however I don't get why if my the octane booster got success, now a cooler plug will get success too... of course I'll try, just I don't get it completelly.

five: was just an extra question about performance and maybe also pinging results between V powers, Iridium, etc... diff kind of spark plugs on same heat range will change something on pinging too ? I know about performance does even never have used or compaired, just talking about by what I have read. I know also durability is a diff too.

[Nacho-RT74]

Wiki has a section on "spark plug heat range" you can read to explain this. 
   Basically the tip of the plug is staying so hot it is igniting the fuel/air before spark when your under heavy load. The trick is to find the range that is cold enough to not ping but be hot enough not to foul out when idle/low speed. You have modified your engine and ignition so think, higher or hotter spark and compression may change heat characteristics of spark plugs from what you were using before.     

Nice!!!, will search!

[Nacho-RT74]

two: there is some diff in performance using hotter or colder spark plugs ?If you have detonation, yes.  Generally, a cooler plug is faster or the same.  Cooler will foul sooner

Cooler will foul sooner ? didn't you want to meant hotter ?

[BSB67]

two: there is some diff in performance using hotter or colder spark plugs ?If you have detonation, yes.  Generally, a cooler plug is faster or the same.  Cooler will foul sooner

Cooler will foul sooner ? didn't you want to meant hotter ?

No

[boss429kiwi]

Answer = 100% octane (AV gas).

Fixed my problem and the engine now runs "crisp"!

[Nacho-RT74]

just noticed there is not XR6 &/or 7s.

no resistor plugs available on the 6 or 7 heat range ?

and... found on my computer ( this is something I just remembered had it saved ) this excel file with all kind of cross reference.

however if you search for the NGK R5670-7 on attachment, it says J12YC and J63Y like being the same than the NGK R5670-7 ?

Also noticed the XR series is with gasket and the ones you advices me on 6 or 7 heat range are tappered. I understand PHISICALLY whats the diff, but not WHY that difference

if so, I have several new RJ12YC what I bought long time ago and several J12YC used but PERFECT. If install this J12YC I have, should I feel a difference ? are the J12YC and J63Y kinda the same ?

[Nacho-RT74]

nice website

http://www.sparkplug-crossreference.com/

[Nacho-RT74]

after check rockauto, and find the AMAZING PRICE of each one  I had to pull the trigger for ALL 16 SPARK PLUGS, 8 6s heat range and 8 7s heat range... will test both and keep on engine the best results ones.

The shipping charges are $11.75 because they will be coming from 3 diff locations ( if just one location maybe I was to pay around $7 )... but WHO CARES. I'll be getting 16 at the price of 8 ( average ), with just one shipping charge ( average ) from any parts dealer for just the 8 units

[b5blue]

Good point Nacho.
  I ordered a set of R5670-7's and should have them today, if the seats are tapered I'll let you know. (?) I've not installed tapered plugs plugs before on my 440 is this gonna work? 

[b5blue]

No worries Nacho the R5670-7 are compression ring sealing type plug. (Part # 2891)