Worked 4k Spark Plug Choices

[reg_ke35]

Hey guys, recently new to Rollaclub, I have a 77 KE35 with a worked 4K.

 

Here are the specs, it has a

-242 .050" thou lift 292 adv cam.

-head shaved 20 thou

-double valve springs

-big port grind

-ramflo air filter on the stock carby ( sad I know )

-extractors 2 inch system

 

Now its quite lumpy on idle and upwards of 2,000rpm, if I let it idle it fuels itself up quite quickly, I haven't had it tuned yet to the cam, but I was wondering would going to a hotter plug help? Or is it just the stock carby? hoping to save a bit to get a redline sidedrought manifold.

 

Any queries would be helpful.

 

Thanks

Edited February 11, 2008 by reg_ke35

[Taz_Rx]

the BP5EY stock plugs should do the trick, but going up to 6's or 7's in the heat range would hurt.

 

I run B6ES plugs in my turbo K. They mightn't make much difference on an NA motor though.

[Raven]

Firstly, are you running extractors?

 

If you're not, you'll get cam reversion and experience what you're experiencing now, though you say you're running a stock carb, which is leading me to think thats its been re-jetted at some point.

 

Still, with a lumpy cam, you need to be running extractors or you wont get the full performance potential of the cam.

Edited February 11, 2008 by Raven

[Felix]

If anything with a worked motor you should be running a plug one heat range colder.

 

A hotter plug is a bandaid for an old motor that burns oil.

 

Tune or rejet your carb so it isn't so rich at idle. Better yet, install a better carb and jet it to suit your engine mods.

 

A question, do you have a functioning PCV system?

Edited February 11, 2008 by Felix

[reg_ke35]

Thanks for the replys,

 

First it does have extractors and a 2 inch system going through it. I should of noted that in the specs. I got the original carby reconditioned about 3 months ago, so I guess its just got the stock jets in it? And yes I do have a functioning PCV valve although the rubber bit that goes in the tappet cover is all broken could that make a difference? But it still seems to seal it?

 

Thanks guys