UR5's Or UR6's???

[cheatham2492]

I have ignition break up after 20 psi. I changed from the stock plugs to the ur5's and I think there too warm of a heat range.There gaped at.28I have a MSD 6A that whent bad. I am trying to get a new one via ebay. I do have the blaster coil. what do ya think wrong plugs??
Thanks Dan

 

[StangBuster]

Re: UR5's Or UR6's???

I heard you can only use the ACdelco plugs...Almost everyone runs them...

 

[rainmaker]

Re: UR5's Or UR6's???

I heard you can only use the ACdelco plugs...Almost everyone runs them...

Ick....bad advice. Read the FAQ about tuning.

I ran the UR5's and 6's in the Bravada and liked em both. I noticed a slight change for the better in drivability using the UR6's. I gapped em to about .31 and had a similar ignition to yours.

Make sure you're datalogging your runs before you go changing anything. Could be a hundred different things causing it to break-up under load. But ignition is probably a good place to start.

 

[sytyguy]

Re: UR5's Or UR6's???

Like Potter said.....forget ACs and go NGK always. Much better idle quality and improved resistance to "blowing out" under boost.

According to my NGK rep, the UR5s are stock heat range for SyTys and the UR6s are a tad colder (better resistance to pre-ignition).

Hood

 

[Timbo]

Re: UR5's Or UR6's???

I think I recall reading that UR6s are no good for Vortech heads. Any truth to that?

 

[SY2455]

Re: UR5's Or UR6's???

I use the NGK UR6IX part #7348 with the MSD6A with no ignition break up, Still using stock coil. The blaster coil when I was using it with the MSD6A used to burn holes in my Conrad cap and rotor.

 

[10secTy]

Re: UR5's Or UR6's???

If you run pump gas and meth injection I have been using UR7IX plugs with great results.

When I tune my truck for our local pump gas drags next year I will use the 8's.

Nolan

 

[Jer]

Re: UR5's Or UR6's???

If you run pump gas and meth injection I have been using UR7IX plugs with great results.

When I tune my truck for our local pump gas drags next year I will use the 8's.

Nolan

Great info! Thanks for that.

 

[dgoodhue]

Re: UR5's Or UR6's???

I think I recall reading that UR6s are no good for Vortech heads. Any truth to that?

For Vortecs you need a different length plug, so yes it true. I think its recommended to use TR5, TR6 plugs for Vortecs...

 

[cheatham2492]

Re: UR5's Or UR6's???

Thanks for the info. I think that I am leaning to 10 sec ty. I put some new stock AC's back in the ty runs better and dosent break up till 22PSi or so. I think that the ur 5's seem like there the stock plug that goes into a normaly asperated 4.3l. TheAC delco blank blank 43's something like that. I had these in my Ty when I bought and they acted the same. That was on a stock motor turbo though. but I think I'll try the NGK url7 or what ever ty 10secty said they were.With a 6A controll box. The ur 6's seem like stock to me. But damn what a diff 18 to 22 psi seem like 75HP to me.
Thanks again keep posting to see what we find out.
Cheatie