How close is too close?
Thread Starter
Drifting
Joined: Aug 2005
Posts: 1,443
Likes: 65
From: Wauconda IL
How close is too close?
I'm trial fitting a set of Hooker 2134's (1 3/4") headers to my 69' SBC coupe.
Plugs 1-7 have gobs of room around them but the tip on #8 is less than 3/8" from the tube (5/16" - 11/32" max).
Heads are 195cc Profilers with straight plugs.
How far away do the plug boots need to be from the tubes to prevent them from frying?
Also, how far away should the tubes be from the steering box?
Would it make sense to wrap the side of the steering box with some sort of heat shielding material?
I am having the tubes ceramic coated but I want to make sure I do any 'massaging' of the pipes before I send them out.
Thanks in advance!
Elm
Plugs 1-7 have gobs of room around them but the tip on #8 is less than 3/8" from the tube (5/16" - 11/32" max).
Heads are 195cc Profilers with straight plugs.
How far away do the plug boots need to be from the tubes to prevent them from frying?
Also, how far away should the tubes be from the steering box?
Would it make sense to wrap the side of the steering box with some sort of heat shielding material?
I am having the tubes ceramic coated but I want to make sure I do any 'massaging' of the pipes before I send them out.
Thanks in advance!
Elm
Thread Starter
Drifting
Joined: Aug 2005
Posts: 1,443
Likes: 65
From: Wauconda IL
How close is too close?
I'd really like to avoid buying one (or a set) different plug if possible.
IE if 3/8" is the magic number than a small flat on that spot of the tube would take care of it without resorting to different plugs.
If it's 1/2" or more, then I would need to consider different plugs.
I just need to know what the 'safe' header to boot distance is.
Thanks!
Elm
Advanced
Joined: Apr 2008
Posts: 92
Likes: 1
From: Carol Stream Illinois
I am running the ceramic coated Hooker 2134's on my '82 with Edelbrock Performer RPM heads with Accel 416SS plugs. I thought I also had a problem with the number 8 cylinder with less than an 1/8
inch of clearance. I never have had a plug wire melt and know you wont either. As far as the steering box, I have about 1/2 an inch of clearance and again haven't had any issues. The ceramic coated headers do a great job of staying cool compaired to stainless or steel headers, so you don't need to worry. Also, just a FYI, the Accel header plugs are 3mm shorter than any other plugs I've found out there.
inch of clearance. I never have had a plug wire melt and know you wont either. As far as the steering box, I have about 1/2 an inch of clearance and again haven't had any issues. The ceramic coated headers do a great job of staying cool compaired to stainless or steel headers, so you don't need to worry. Also, just a FYI, the Accel header plugs are 3mm shorter than any other plugs I've found out there.
Burning Brakes
Joined: Nov 2011
Posts: 1,170
Likes: 201
From: Willoughby Ohio
I agree with all of the above.Between the shorty header plugs and the
boot protectors (sum-350119) you should be fine.If you do not mind I
would like to ask about your heads.I am looking to put together a 415 or
421 stroker with their 210 straight plug heads.The profiler heads appear
to be some pretty impressive heads in as cast form.I am asking because my ss side pipe headers are for straight plug heads.Any feedback you can give would be greatly appreciated.Feel free to pm me
if you are more comfortable with that.
boot protectors (sum-350119) you should be fine.If you do not mind I
would like to ask about your heads.I am looking to put together a 415 or
421 stroker with their 210 straight plug heads.The profiler heads appear
to be some pretty impressive heads in as cast form.I am asking because my ss side pipe headers are for straight plug heads.Any feedback you can give would be greatly appreciated.Feel free to pm me
if you are more comfortable with that.
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
3/8 could be an issue but you'll likely be OK at that space. It will really depend on the engine tuning and how hot it makes the headers. I find I needed more space when the header pipe goes over/behind the boot then when the boot is beside the pipe for some reason. Maybe because it holds more heat around the boot. I just bought a single shorty plug for the tube clearance problem I had - simplest way to fix it.
The heat sleeves didn't help me when the sleeve ended up tight between the boot and the header. The heat eventually burned through both the sleeve and the boot.
The heat sleeves didn't help me when the sleeve ended up tight between the boot and the header. The heat eventually burned through both the sleeve and the boot.
Thread Starter
Drifting
Joined: Aug 2005
Posts: 1,443
Likes: 65
From: Wauconda IL
I agree with all of the above.Between the shorty header plugs and the
boot protectors (sum-350119) you should be fine.If you do not mind I
would like to ask about your heads.I am looking to put together a 415 or
421 stroker with their 210 straight plug heads.The profiler heads appear
to be some pretty impressive heads in as cast form.I am asking because my ss side pipe headers are for straight plug heads.Any feedback you can give would be greatly appreciated.Feel free to pm me
if you are more comfortable with that.
boot protectors (sum-350119) you should be fine.If you do not mind I
would like to ask about your heads.I am looking to put together a 415 or
421 stroker with their 210 straight plug heads.The profiler heads appear
to be some pretty impressive heads in as cast form.I am asking because my ss side pipe headers are for straight plug heads.Any feedback you can give would be greatly appreciated.Feel free to pm me
if you are more comfortable with that.
The 195 Profilers had better flow numbers out of the box than I could ever hope to get out of those Vortecs. I went with the 195s because I wanted low end torque more than high RPM horsepower (I don't plan on turning much over 5500 RPM).
I am just in the process of getting everything installed so I have not had a chance to see how they run but my builder says these heads are good for up to 600 HP provided everything else is matched to make that kinda power. I had him do just a basic 'econo port' and a 5 angle valve job and my intake numbers are 294 at .550 lift.
I'm not looking for anything quite that extreme but 500 Ft/Lbs TQ shouldn't be too hard of a stretch.
Let me know if you had any specific questions and I'll try to answer the best I can.
Elm
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Thread Starter
Drifting
Joined: Aug 2005
Posts: 1,443
Likes: 65
From: Wauconda IL
3/8 could be an issue but you'll likely be OK at that space. It will really depend on the engine tuning and how hot it makes the headers. I find I needed more space when the header pipe goes over/behind the boot then when the boot is beside the pipe for some reason. Maybe because it holds more heat around the boot. I just bought a single shorty plug for the tube clearance problem I had - simplest way to fix it.
The heat sleeves didn't help me when the sleeve ended up tight between the boot and the header. The heat eventually burned through both the sleeve and the boot.
The heat sleeves didn't help me when the sleeve ended up tight between the boot and the header. The heat eventually burned through both the sleeve and the boot.
Worst case I can put on an insulating boot on the one wire or the short plug but I think I should be safe now as-is.
Thanks!
Elm
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Your heads and others like AFR angle plugs have header to plug boot clearance problems. The only real fix is to take a band saw and cut the pipes off the flange and have 3/8th to 1/2 inch added pipe to the primary tubes.
Because of the sbc head down angle the headers will still have clearance to steering etc.
Or you can cheap out and dent the header tubes. The steering box can handle heat. I've had hooker 1 3/4 since the 80's. Just pump it full of red grease
Because of the sbc head down angle the headers will still have clearance to steering etc.
Or you can cheap out and dent the header tubes. The steering box can handle heat. I've had hooker 1 3/4 since the 80's. Just pump it full of red grease
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Same here using Taylor Spiro wound wires and Hooker SS side mount headers. I thought it was too close but it has never burned the silicone.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
#113 GM aluminum SBC heads here, like on L98, went Jacobs ceramic boots on all 8 and kissed all the boot problems good by, they gave me a cow for a while, with 5&6 burning through/melting
Burning Brakes
Joined: Nov 2011
Posts: 1,170
Likes: 201
From: Willoughby Ohio
Thanks for sharing the information about the heads.I plan on ordering
the 210 profilers after I get confirmation on the correct combustion
chamber size.Right now I'm leaning towards the shp short block with
the callies compstar rotating assembly.After I get the heads the victor jr intake I have will get some plenum work and port match on cnc mill.
This engine is getting a hydraulic roller cam and will be set up to run to
6500 rpm.I have 3.70 gears to put into differential and will be installing a 2004r transmission.I would be more than happy to share notes on
combinations as this progresses.
I'm looking forward to spending more time on the car and less on the
computer.
Dave
the 210 profilers after I get confirmation on the correct combustion
chamber size.Right now I'm leaning towards the shp short block with
the callies compstar rotating assembly.After I get the heads the victor jr intake I have will get some plenum work and port match on cnc mill.
This engine is getting a hydraulic roller cam and will be set up to run to
6500 rpm.I have 3.70 gears to put into differential and will be installing a 2004r transmission.I would be more than happy to share notes on
combinations as this progresses.
I'm looking forward to spending more time on the car and less on the
computer.
Dave