Engine Build Planning Question
Thread Starter
Cruising
Joined: May 2021
Posts: 10
Likes: 0
From: Southwestern Ontario
Engine Build Planning Question
Hello all,
I have an '85 that I picked up recently. I'm in planning stage of building up the existing 350. I've only bought these headers so far.
Does anyone know which type of head I need so that there is enough clearance for the plugs (i.e. should I be getting the slanted outlets for the spark plugs or will there be enough clearance for the ones that come out straight?).
Appreciate any insight.
I have an '85 that I picked up recently. I'm in planning stage of building up the existing 350. I've only bought these headers so far.
Does anyone know which type of head I need so that there is enough clearance for the plugs (i.e. should I be getting the slanted outlets for the spark plugs or will there be enough clearance for the ones that come out straight?).
Appreciate any insight.
Team Owner
Joined: Sep 2001
Posts: 62,140
Likes: 1,728
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
It will fit the L98 angled plug heads, should fit the straight plug head too. The angling should be listed on any head description for a head you intend to buy from Jegs/Summit etc. The difference is how much a PITA it is to get to a couple plugs.
So what is the head you are wanting? it would be easier to answer that way.
So what is the head you are wanting? it would be easier to answer that way.
Thread Starter
Cruising
Joined: May 2021
Posts: 10
Likes: 0
From: Southwestern Ontario
Thanks for the Reply.
I'm thinking these heads (which are straight plugs).
Do you have a recommendation as to if I should find an equivalent angled head or run with these?
I'm thinking these heads (which are straight plugs).
Do you have a recommendation as to if I should find an equivalent angled head or run with these?
Team Owner
Joined: Sep 2001
Posts: 62,140
Likes: 1,728
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I would generally go for the angled plug head, yes.
I don't know ProMaxx flow numbers but I'd research more of that data vs price. Most of us here, including myself, push AFR 190s, but they are not cheap heads.
I don't know ProMaxx flow numbers but I'd research more of that data vs price. Most of us here, including myself, push AFR 190s, but they are not cheap heads.
Thread Starter
Cruising
Joined: May 2021
Posts: 10
Likes: 0
From: Southwestern Ontario
Le Mans Master
Joined: Aug 2017
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From: New Jersey
The jegs brand 195 cc heads (profiler) are also an option. But the exhaust port is raised which can potentially cause a plug clearance issue. It's a lot of head for the money. Not quite an AFR but you need to value what you want vs what you're willing to spend.
Thread Starter
Cruising
Joined: May 2021
Posts: 10
Likes: 0
From: Southwestern Ontario
Hey Vader,
I have one more question if you do not mind.
I'm looking at these valve covers, do you know if there will be enough clearance for the wiper motor?
Thanks,
I have one more question if you do not mind.
I'm looking at these valve covers, do you know if there will be enough clearance for the wiper motor?
Thanks,
Team Owner
Joined: Sep 2001
Posts: 62,140
Likes: 1,728
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I don't have the PN for the AFR covers i'm using but they aren't tall style covers, the tall height does not work, so I can't tell you for sure, but I doubt those will clear the wiper motor. You'd have to use stock height.
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If you do, Vader meant their 195's. Or...even their 180's -- depending on your needs. You can get better flow using a smaller cam with the 195's. The headers you bought aren't a match for the 195's though. (no idea on the 180s) 195 exhaust ports are bigger than those Hedman header inlets [you bought]. You should pick the heads THEN the headers that will fit.