Spark plug choices 🤔
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Teching In
Joined: Oct 2020
Posts: 25
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Spark plug choices 🤔 Too many plugs to choose from. I’ve got an older lq4 I am installing a bald eagle na cam into. Headers stock coils. Nothing special here but would appreciate a plug recommendation. Also. Should I use factory recommended thermostat? Engine will be in square body with new aluminum 3 core radiator
NGK tr55 have been the go to plug for 20 years for LS builds like yours. I use NGK in everything, from my lawn mower to my boosted and nitrous builds and my customers cars. I've had better luck with NGK plugs than any other brand. Never had a problem from AC Delco either though, so you could also use the OE replacement NGK plug or AC Delco. They should be platinum plugs which last a lot longer than copper plugs, like the TR55's, but I had TR55's in my last 2 LS cars and the plugs lasted for years.. I sold the cars before the plugs wore out so copper NGK's are also fine, and only $2 or so a piece
https://www.texas-speed.com/p-100-ng...park-plug.aspx
as for thermostat, up to you. I keep stock temp thermostats in my junk but my junk gets driven daily and needs hot heat and I want the engine to fully warm up. With a toy a 160, 190, or stock 195 will all work fine.
https://www.texas-speed.com/p-100-ng...park-plug.aspx
as for thermostat, up to you. I keep stock temp thermostats in my junk but my junk gets driven daily and needs hot heat and I want the engine to fully warm up. With a toy a 160, 190, or stock 195 will all work fine.
I had to go look up the TR5 lilvjay10 posted about versus the tr55
They are identical except for the gap that is pre set on the plug. I personally usually set the tr55 at .040 on a stock or heads cam setup and never knew the tr5 comes out of the box at .039, the tr55 comes out of the box at .059 so the tr5 is actually closer to correct out of the box, but you can gap either to what you want.
Good call on the tr5 lilvjay10, and I learned something new today.
They are identical except for the gap that is pre set on the plug. I personally usually set the tr55 at .040 on a stock or heads cam setup and never knew the tr5 comes out of the box at .039, the tr55 comes out of the box at .059 so the tr5 is actually closer to correct out of the box, but you can gap either to what you want.
Good call on the tr5 lilvjay10, and I learned something new today.
Not to question the experts here, but I've been told and have run TR6 in a H/C/I motor.
Another tip to OP: Gap every plug yourself (don't trust out-of-box) and always buy more than 8, in case you drop one, like I do, in the process.
Another tip to OP: Gap every plug yourself (don't trust out-of-box) and always buy more than 8, in case you drop one, like I do, in the process.
TR6 works also. It's one step colder. It's a hard call on TR5 or 6 since it's cam only in a LQ4
Will have to monitor knock and if there's an issue go to 6's. But with a fairly mild setup and not high compression a 5 is likely fine. But every setup can be a little different.
Also be just fine to start off with 6's
Will have to monitor knock and if there's an issue go to 6's. But with a fairly mild setup and not high compression a 5 is likely fine. But every setup can be a little different.
Also be just fine to start off with 6's
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I have another suggestion for you. I have used Autolites and Champions all my life. The motors ran well on each brand. In recent years, I have used Autolites exclusively. The 5245 is the standard plug and the 5243 is a little colder, and the type I tend use. 104s work OK too. 104s are an old school universal plug with applications for many different make and models. They have a proven track record with boost and .708 reach.
As to platinum tips, I prefer single platinums over double since they run cooler. The AP 5243s have platinum anodes and regular ground straps. The anodes are also focus pointed and thinner than the standard 5243, more like an Iridium plug. If you need a racing plug, than check out AR 94s which are cut back and not really for street use.
NGK is a big name on this forum, but I have never used them. But I can tell you this, I never had a problem with Autolite plugs and all my motors run smooth and strong. Hope this helps.
As to platinum tips, I prefer single platinums over double since they run cooler. The AP 5243s have platinum anodes and regular ground straps. The anodes are also focus pointed and thinner than the standard 5243, more like an Iridium plug. If you need a racing plug, than check out AR 94s which are cut back and not really for street use.
NGK is a big name on this forum, but I have never used them. But I can tell you this, I never had a problem with Autolite plugs and all my motors run smooth and strong. Hope this helps.
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Verdad Gallardo All I can really add is that I'm a tech and have been working in shops all day for a living for 22 years. I've done and been around 1000's of plug changes (i've done a lot and worked beside other techs doing them all day and seen/heard their issues) on customer cars, all my 15 or so cars I have owned, all the performance shops I have gone to and friends that I know that own race shops and or build race cars, and all of the stuff I have read on these forums for 20 years... We all stick to NGK, or have arrived at using and sticking to NGK.
NGK has had the least come backs in the shop out of all the brands I have used. I have seen 1 bad NGK out of thousands of plug changes.
I have fixed issues I have personally had with other brands of plugs by putting in NGK's
And NGK's are the absolute go to spark plug for big name tuners, racers, import or domestic. There's a reason why. Before I built LS stuff I did turbo and nitrous honda stuff.
NGK the world lol
That all being said, most big name spark plug brands are going to work just fine though and I've had fairly good luck from all brands if you look at the total I've installed versus issues I have had, they're all good these days. But do watch out for knock off's they are out there. Buy from reputable companies and the prices seem extra low, they're fake plugs.
NGK has had the least come backs in the shop out of all the brands I have used. I have seen 1 bad NGK out of thousands of plug changes.
I have fixed issues I have personally had with other brands of plugs by putting in NGK's
And NGK's are the absolute go to spark plug for big name tuners, racers, import or domestic. There's a reason why. Before I built LS stuff I did turbo and nitrous honda stuff.
NGK the world lol
That all being said, most big name spark plug brands are going to work just fine though and I've had fairly good luck from all brands if you look at the total I've installed versus issues I have had, they're all good these days. But do watch out for knock off's they are out there. Buy from reputable companies and the prices seem extra low, they're fake plugs.
Final thought. I know that NGK is currently in vogue as is the internet speed shops. My 1st cam was an Iskandarian, sold by a local proprietor on the east side of Chicago. Comp cams did not exist for instance. This is not to say the newer brands are bad,
But a few years ago NGK, like Accel before it, started selling V groove plugs with purported performance benefits. I am not saying they are bad plugs, but the V groove is a marketing strategy and doesn't really boost performance. That being said, try a few different brands until you find the one you like the best.
But a few years ago NGK, like Accel before it, started selling V groove plugs with purported performance benefits. I am not saying they are bad plugs, but the V groove is a marketing strategy and doesn't really boost performance. That being said, try a few different brands until you find the one you like the best.
TECH Apprentice
Joined: Apr 2019
Posts: 365
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From: California
I will say if there is any doubt go with the majority on this and run NGK. There seems to be a lot of information on NGK plugs so that should help. When I got my spark plugs I had actually asked for the copper plugs, but the person at Oreillys grabbed the platinum plugs by mistake. Anyway the research I've done turns up copper plugs as the best for performance, but they do wear out faster.
The A 5245 is the standard copper plug. Platinum tends to hold in the heat. Thats why I also use the APs since they are anode only coated. They are fine for street use, and last a little longer. You really only need a copper plug for race motors.