Hot Rod Forum : Hotrodders Bulletin Board - Reply to Topic
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine> Spark plug no longer aval . ac 43N
User Name
Password
lost password?   |   register now

Thread: Spark plug no longer aval . ac 43N Reply to Thread
Title:
  
Message:
Trackback:
Send Trackbacks to (Separate multiple URLs with spaces) :

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Additional Options
Miscellaneous Options

Topic Review (Newest First)
07-05-2008 01:22 PM
carsavvycook
Quote:
Originally Posted by DENCOUCH
Perhaps I learned the wrong lesson sometime ago, but it has been my held belief that the opposite is true.

A hotter plug than required is detrimental in that it retains heat which can lead to expensive problems in a motor. A plug that is in the too cold heat range fouls easier as the heat from the plug is transferred too quickly to the cylinder head.

With this reasoning, I would believe that it would be worse to have a "too hot" plug in a lean condition than it would be to have a "too cold" plug.
You are correct. I should have "proof read", not just "Spell Check".
07-05-2008 11:41 AM
DENCOUCH
Question..

Quote:
Originally Posted by carsavvycook
It looks like you have problems other than just spark plug heat range.

You went bigger on the camshaft, and just a touch on compression. You will need to re-jet the carb richer, by a couple jet sizes, at least. The "very white plugs" says you are running too lean now. The "pop now and then at idle", says you might have a real lean mixture at idle.(possible vacuum leak) Also MSD recommends a plug gap starting at .050 to no more than .060, for their products to operate best. The fuel you are using will play a part in your tune.

A spark plugs "heat range" is determined by the engines cylinder temperature. In other words, a "hotter plug" is designed to perform best in higher temperature's, as in a "lean mixture". and "colder plug" would perform better with a richer mixture. The plug does not "burn" hotter, it will just dissipate the heat slower, keeping the plug "hotter".

You also changed gears, and converter which is going to have to be close, rpm wise, to the "grind" of the camshaft.
Perhaps I learned the wrong lesson sometime ago, but it has been my held belief that the opposite is true.

A hotter plug than required is detrimental in that it retains heat which can lead to expensive problems in a motor. A plug that is in the too cold heat range fouls easier as the heat from the plug is transferred too quickly to the cylinder head.

With this reasoning, I would believe that it would be worse to have a "too hot" plug in a lean condition than it would be to have a "too cold" plug.
07-05-2008 11:07 AM
dawg heres a cross reference for your plug
http://www.sparkplugs.com/results_cr...CrossWarning=1
07-05-2008 08:35 AM
66bowtie
sparkplug no longer available

Here is a pretty good site on plugs. It May help you pick a heat range for your engine.
http://www.autohausaz.com/html/spark...lug-wires.html
07-04-2008 11:29 PM
carsavvycook Check your exhaust temps at the header ports of each cylinder. An infrared hand held unit with a lazer pointer works good. You will be OK between 650 and 850 at hot idle with your set-up. At higher rpms you would want it no more than 1350.
07-04-2008 10:58 PM
carsavvycook I forgot to add. Everything on your "tune-up" is going to change with the air temp, and humidity,= barometric pressure, at the time you run. On a cool evening you may have to drop a "heat range", or possibly a "jet" size or 2.

What you need to find is a "happy medium" to start with, with this new engine. Good luck, and Gods speed. Go get em!
07-04-2008 10:38 PM
Tommy B Thanks carsavvycook ,

compression is 11.5 so i could up the gap to .040 to .050 as msd says for 10.5 to 13 compression ratios

I did try re jetting the carb also : 84 /82 , when i removed the rear power valve i went to 90 in back ( 850 dp ).

i checked for vac leak and exhaust leaks as well .. none were found , car dies very quickly if i cover the choke area .

Iam using 110 oct. fuel . I had a couple people at the track tell me the pop could be a vac leak as you mentioned or something about the fuel igniting with a plug to hot and is creating a hot spot in the combustion chamber and some fuel is unburnt creating that pop , cold fuel , hot exhaust .

I just know it don't sound good but yet yet the car runs quite well as long as iam not idle or just slightly above it . I will check the air mixture screws again with the vac gauge but was sure i did it right . I can only think of plugs after i check that , I guess since the plug now is a hot plug i could try one or two steps colder . The being lean iam afraid will hurt something .
07-04-2008 09:51 PM
carsavvycook
Quote:
Originally Posted by Tommy B
Thats the plug heads orignally took . I heard to use delco r43xls now . Do i need to go up or down in heat range since i'am 30 over now and added a bigger cam and about .5 point compression , gears and a convertor . I don't drive the car on the street , its just a toy at the track . I tried NGK bpr4es but the plugs stay very white and i get a pop now and then at idle ,more so when engine is not to operating temp . ( I think that means the plug is too hot correct ? ) i have msd ing and 6al box if that matters . I gapped the plugs at .35 also .
It looks like you have problems other than just spark plug heat range.

You went bigger on the camshaft, and just a touch on compression. You will need to re-jet the carb richer, by a couple jet sizes, at least. The "very white plugs" says you are running too lean now. The "pop now and then at idle", says you might have a real lean mixture at idle.(possible vacuum leak) Also MSD recommends a plug gap starting at .050 to no more than .060, for their products to operate best. The fuel you are using will play a part in your tune.

A spark plugs "heat range" is determined by the engines cylinder temperature. In other words, a "hotter plug" is designed to perform best in higher temperature's, as in a "lean mixture". and "colder plug" would perform better with a richer mixture. The plug does not "burn" hotter, it will just dissipate the heat slower, keeping the plug "hotter".

You also changed gears, and converter which is going to have to be close, rpm wise, to the "grind" of the camshaft.
07-04-2008 08:32 PM
Tommy B
Spark plug no longer aval . ac 43N

Thats the plug heads orignally took . I heard to use delco r43xls now . Do i need to go up or down in heat range since i'am 30 over now and added a bigger cam and about .5 point compression , gears and a convertor . I don't drive the car on the street , its just a toy at the track . I tried NGK bpr4es but the plugs stay very white and i get a pop now and then at idle ,more so when engine is not to operating temp . ( I think that means the plug is too hot correct ? ) i have msd ing and 6al box if that matters . I gapped the plugs at .35 also .

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


All times are GMT -6. The time now is 05:02 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.