spark plug suggestions for .030 over 440

[goose69]

I'm looking for suggestions for spark plugs for my warmed up 30 over 440. It will be in a '66 belvedere running on the street on pump gas. It does have forged pistons, closed chamber heads with approx 9.7-1 comp. This motor is nothing extravagant and has a bunch of speed parts I had lying around the shop. Eventually when motor is broken in I want to spray some nitrous on top of it........maybe. Oh who am I kidding, heck yea I will, later tho.

 

[70rr-brian]

Just get a colder plug and reduce the gap when you go with nitrous.

But a nitrous motor really needs to be planned from the beginning. Lower compression, good spark system, full pump, retarded timing, ring gap, piston type etc...

I would highly recommend doing a lot of reading before you add nitrous and find out what works best for your build. The racers forum might be a good place to ask those questions too.

 

[goose69]

Just get a colder plug and reduce the gap when you go with nitrous.

But a nitrous motor really needs to be planned from the beginning. Lower compression, good spark system, full pump, retarded timing, ring gap, piston type etc...

I would highly recommend doing a lot of reading before you add nitrous and find out what works best for your build. The racers forum might be a good place to ask those questions too.

I did assemble the motor with the intentions of using nitrous. I gapped my rings accordingly and put my compression where it should work with or without the bottle well, I hope. I also have an adjustable timing control for when the bottle is squeezed onto the motor. I have a good fuel system for it too. Now just to let people know I will only be shooting 75-100hp of nitrous set up onto the motor. But I will not be adding this for a while, after running the motor for a while like I mentioned before.
Thanks guys.

 

[Meep-Meep]

For non N2O I'd run the stock heat range. I used to use Autolite 74's but I think all you can get these days is the resistor version and one step hotter. Those are 85's. I run the 85's now and made several passes without burning the electrodes off. For N2O you might go one step colder. I never heard of the tightening the gap for N2O but the result would ensure you get a spark at the plug every time so a good idea. Perhaps just as high compression tries to blow the spark out N2O might do the same, so a tighter gap would solve that problem.

 

[goose69]

For non N2O I'd run the stock heat range. I used to use Autolite 74's but I think all you can get these days is the resistor version and one step hotter. Those are 85's. I run the 85's now and made several passes without burning the electrodes off. For N2O you might go one step colder. I never heard of the tightening the gap for N2O but the result would ensure you get a spark at the plug every time so a good idea. Perhaps just as high compression tries to blow the spark out N2O might do the same, so a tighter gap would solve that problem.

Thanks for the suggestions!

 

[Dennis H]

Don't know about later, but my warmed 440 likes the NGK's?

 

[ykf7b0]

I'm looking for suggestions for spark plugs for my warmed up 30 over 440. It will be in a '66 belvedere running on the street on pump gas. It does have forged pistons, closed chamber heads with approx 9.7-1 comp. This motor is nothing extravagant and has a bunch of speed parts I had lying around the shop. Eventually when motor is broken in I want to spray some nitrous on top of it........maybe. Oh who am I kidding, heck yea I will, later tho.

Your combo looks alot like mine but I'm at 10.15-1 compression. I have a 175 shot of nitrous that I haven't sprayed very often but I did spray 125 shot many times. I had no problems at all with Champion RJ12YC even though I know I should have been using a couple heat ranges cooler. I think I will go with some Champion RJ9YC or R10YC when I really get to using the 175 shot.

 

[goose69]

Your combo looks alot like mine but I'm at 10.15-1 compression. I have a 175 shot of nitrous that I haven't sprayed very often but I did spray 125 shot many times. I had no problems at all with Champion RJ12YC even though I know I should have been using a couple heat ranges cooler. I think I will go with some Champion RJ9YC or R10YC when I really get to using the 175 shot.

Thanks bud. I'll look into that. I do believe the RJ9YCs are ones I was considering.

 

[Montclaire]

I like Bosch platinums.