I have a 454 .30 over 10.5:1 compression. Flat tappet hydraulic marine cam and HEI. Also have air gap manifold and aluminum mercruiser exhaust (not logs). Which spark plug should I use and what gap should they be set at. Thanks! Almost got this bitch running! Trying to make it to Havasu in 3 weeks.

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what heads?  Casting number. ..?


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Ac Delco R44T

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I'll go with that

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Yes I do know about indexing. Well I understand the concept. But I'll do some more research about it. Thanks guys!

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FYI I run MR44TS, extended tip plug seems to idle a bit cleaner... Might just be me though.

GT

Just a quick touch on the subject of spark plug indexing, there is no reason to spend the time indexing plugs unless you have a combination of combustion chamber shape and piston dome that would have a clearance issue with the plugs ground strap. I have never seen any proof of performance gain ever indexing plugs, and I have spent alot of time in engine dyno cells over the years, with customers along with my own racing engines. I have dicussed this topic with pro stock racers like Jason Line, Warren Johnson, Larry Morgan, David Nickens and Mountain View Racings, Dave Beckley so on, they all say it's not worth anything accept for piston dome clearance, if needed. If there was any free power left on the table for these guys, don't you think they would scoop it up? Just thread your plug's of choice in your 049 castings and go play.

The only time we ever played with indexing was on sprint car engines. They always wanted the "flame front" to be towards the center of the valves. It had to do more with engine longevity than actual power.  I am certain only because these engines were run just past the ragged edge.

GT

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Sooo which is it?

I don't understand your four word question. ...


If you want the best performance from your spark plug and achieve consistent readings from cylinder to cylinder, indexing is the way to achieve that.

I have personal experience with it on 410 small blocks.  There is no wishy washy in there. ..

WTF is your issue?

If it is a debate you want.  I'm game.  Only rule is, one subject at a time. .... I'm getting old.

GT

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Got a few problems

The problem with you is you ALWAYS got something to say.

 

I can explain that.... I am on the computer about 3 hours a day for work. I leave SoCal open in the corner. When I need to take a break from writing a report or a proposal, I hit up the forum.... 

You asked the guy if he knows about indexing to get porformance

It is spelled performance but whatever. I never said anything about better engine performance, I said spark plug performance and better "readability". There are numerous blogs and documentation on the subject and thousands of forums discussing it at length. I will tell you the reason I brought it up was because I was surprised when the guys in the GN class were in the pits spending a lot of time insuring the plugs were indexed correctly. I have been doing it sloppily for years, these guys were pretty accurate about it.

Other guy says its not needed.  Then you say oh Only time we ever played with it was on sprint cars but it wont give you extra power just longevity.

 

Not true, I said that was the only time we "played with indexing" to see what differences it makes. I do always try to keep the electrodes perpendicular to the valves. Just habit, not always feasible.

Im done just tired of u always git some shit to say.  U got 8000 posts.  Take your old ass back out to the garage and work on something.  Or take your damn boat out.

 

Can't work on the computer and the garage crap at the same time, the shop (my grandmothers 4 car garage), is 3 miles form the computer....

Went boating nine times so far this year. Five at Nacmiento, once at Long Beach Marine Stadium, twice in the ocean and once at lake Shasta, going to Shasta again on the 13th of this month for a week.

How many times you been out this year?

Don't see the relevance... 

Hi you've reached GT Jets I cant answer the phone right now cause I'm on a forum telling all these dumb asses what to do on their damn boats.  Damn forum should be called "Deep Thoughts"  by GT Jets.

No one is forcing you to read my shit.... Just trying to help whenever I can. There is a lot of misinformation out there. I make my living on idiots "phoning it in".

This site was put together to get information out there in the jet boating world. If you can't call bullshit on someone, there would be no point in the existence of this site. If anybody else has an issue, go ahead and call me out, but I try very hard to keep the information as real and as complete as I can.

Take it or leave it. You will notice there is a large percentage of threads I don't participate in. I also take time off from here to there.

Put on your big boy pants and get over it.

It does not sound to me like you have a problem with any of the information I have shared. I also try to be as politically correct as humanly possible.

Something you could use some training in.

GT

While I am at it and still a little torqued.

I have been a mechanic in the professional sense all my life. I will have 30 years as a professional mechanic in October. I started at the age of 18, the years before that, I raced motorcycles, hydroplanes, go carts, micro midgets and stock cars, my uncle got into Sprint cars and I was on the team, my dad owned a a late model dirt tracker and my other uncle on my moms side has been a professional and expert motorcycle racer since before I was born...

After 18 I have raced whitewater jet boats , desert motorcycles and owned and operated my own boat shop until my accident in 1997.

GT

While I am at it and still a little torqued.

I have been a mechanic in the professional sense all my life. I will have 30 years as a professional mechanic in October. I started at the age of 18, the years before that, I raced motorcycles, hydroplanes, go carts, micro midgets and stock cars, my uncle got into Sprint cars and I was on the team, my dad owned a a late model dirt tracker and my other uncle on my moms side has been a professional and expert motorcycle racer since before I was born...

After 18 I have raced whitewater jet boats , desert motorcycles and owned and operated my own boat shop until my accident in 1997.

GT

I know you know your shit when you talked about thermoquads most people today have no clue what they even are!  Lol

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What would be the issue if I used R45 plugs? The reason I ask Is that is what I already have. I have a set that I was going to use in my small block powered El Camino. Can I run these plugs? Why not?

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