Angle of plugs
Thread Starter
Supreme Member
Joined: Jan 2003
Posts: 1,323
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From: Arthur, Ontario, Canada
Car: 92Z28, 99SS, 83Z28 & 86GTA
Engine: 421, LS1, 327Turbo & 383
Transmission: T-56, 4L60E, T5 & 4L60
Axle/Gears: 4:10, 3:42, 2:73 & 3:27
Angle of plugs
What angle is our plugs? L98 or Straight? I was wanting to grab a set of AFR's but didnt know what plug angle to go as my SLP headers state that they may not work with some plug angles.
Supreme Member
Joined: Feb 2000
Posts: 3,145
Likes: 1
From: Kemptville, Ontario, Canada
Car: 1992 Z28
Engine: 355
Transmission: 700R4
Stock B2L heads have a straight plug angle. When you order the AFR's ask for the L98 angle plugs. Standard angle plug heads have fitment problems on thirdgens because the strut towers crowd the headers. This forces a bend straight off the flange that prevents decent plug clearance.
That MAY be the right answer. I would ask AFR for their recommendations. The thing you have to understand is that once you start playing mix-n-match with headers and heads nobody really knows for sure unless they have done that exact combo before.
My AFR straight plug heads fit my headers which were designed for straight plug headers (don't worry about the brand- different car, different headers). BUT.... AFR stright plug heads ahve the plug offset laterally about 1/4" towards the exhaust port. So stock manifold probably wouldn't work, despite the fact I'm going straight-to-straight.
Did you know that AFR exhaust ports are also about 1/4" higher than stock heads? Well, they are.
Many times- no biggie. But depending on your combo of parts sometimes it's a very big deal.
My AFR straight plug heads fit my headers which were designed for straight plug headers (don't worry about the brand- different car, different headers). BUT.... AFR stright plug heads ahve the plug offset laterally about 1/4" towards the exhaust port. So stock manifold probably wouldn't work, despite the fact I'm going straight-to-straight.
Did you know that AFR exhaust ports are also about 1/4" higher than stock heads? Well, they are.
Many times- no biggie. But depending on your combo of parts sometimes it's a very big deal.
Thread Starter
Supreme Member
Joined: Jan 2003
Posts: 1,323
Likes: 0
From: Arthur, Ontario, Canada
Car: 92Z28, 99SS, 83Z28 & 86GTA
Engine: 421, LS1, 327Turbo & 383
Transmission: T-56, 4L60E, T5 & 4L60
Axle/Gears: 4:10, 3:42, 2:73 & 3:27
eek, now I am scared again
I guess I can call AFR and see what they say. I just have herd horor story's with false info so was hoping to find someone that has them already.
I guess I can call AFR and see what they say. I just have herd horor story's with false info so was hoping to find someone that has them already.
Senior Member
Joined: Jul 1999
Posts: 784
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From: Sacramento, CA
Car: 89 Iroc
Engine: 383
Transmission: 700R4
Axle/Gears: 3.45
I have AFR 190s with L98 angle plugs. I also have Edelbrock TES headers. The plugs clear with no problem. I did have to shorten my spark plug socket and use a wrench to get them out though because a ratchet will hit the headers in a few spots.
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Joined: Nov 2000
Posts: 1,760
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From: Newark, DE
Car: 86' Z28
Engine: 355
Transmission: T-56
now i'm a little confused.
my TFS heads are angle plug, they look like this:
\ / \ /
so what are l98 angle plugs? this?:
/ / / /
Help me out here
Eric
my TFS heads are angle plug, they look like this:
\ / \ /
so what are l98 angle plugs? this?:
/ / / /
Help me out here
Eric
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