Fozzy_Bear

Hi All.
I just installed TPIS long tube headers and plug number 7 is very close to the tube. I want to put a shorter spark plug in to give myself a little space (using Accell U groove plugs right now). I am sure I can spend 2 hours searching and find a list of plugs that would fit, but does anybody have any personal recommendations?
I am using stock heads (late '86 aluminium) now. And I will be swapping in a set of twisted wedge heads when I do a rebuild later this year.

thanks

steve40th

Mr Gaskets website has Accels numbers, but I think they are the only short plug. Yo might want to also call Myron at TPIS and see what plug they use. I put a socket on one of my plugs, then tighten it, and the boot is real close to the header.
Accels tech line responded to me last night within a couple housr. But, they say they only make platinums for mine, 93 LT1.

snoopdan

Sounds like you have similar problems with your headers. My other thread about my headman woes might help ya. Us 86L owners have a few issues with headers, it appears.


snoopdan

steve40th

That is strange, even with the shorter plugs? Does anyone else have shorter plugs. Dimpling the headers doesnt hurt, and I have heard of TPIS headers having to have this done.

CTYANK2

LD85

header shorty plugs summit racing # acc-0414s and acc-0416s

Jegs # 111-0416s 14mm X .750 $2.99 each.

Summit has a ten day back order wait.

Fozzy_Bear

They do have slight dimples for a few of the bolts, but nothing for the plug boots.

I _DO_ have thick boots (MSD) and there _IS_ some space (like .010") so I am not claiming that the headers are poorly designed (the Y pipe sucks, but that's a different thread). I just want a little more safety margin than that. I have ordered some heat insulating material from the forrum store; that will probably do the trick. I skimmed Snoop's thread and it was kind of the reason I was posting the question. a few people mentioned short plugs, so I thought I'd ask the question more specificly and see what people had to say.

Fozzy_Bear

Thanks,
But do you have any personal experience with those particular products? I was hoping to get some feedback from people who have actually used them.

steve40th

They are the U Groove, which is very similiar to the V Groove in NGK. I cant see really how plugs are made any different. There is probably a company thaqt is contracted to do the plugs for Accell.

JAKE

Champion makes a RC series plug that is almost 1/4" shorter than regular plugs. Edelbrock recommends using that series for more clearance.

Something like RC12YC.

Jake

steve40th

Jake, I have an LT1, do you know if that is the same plug by chance, or do I need to just go down and find some Champion plugs?

steve40th

Hey I just went to the Jegs website and they have 2 plugs there, a RC12YC that is a .750" reach, and a RV12YC that is a .460" reach. I checked Accels and they say LT1 have a .460" reach for the recommended plugs needed. SO is the LT1 that different to the L-98 motors?
The reason I say this is Edlebrock does recommend the RC12YC, but Accell recommends the .460" reach, and I believe the reach part is how m\far the plug goes into the head?

JAKE

Steve, I've got an Excel file with TONS of plugs in a cross reference format. If you'd like it, let me know and I'll send it.

Might help you out.

Jake

vettefast

These are the plugs I had to change to after I had my 383 built with Hooker long tube headers. To date they work great and hasn't missed a beat. Also I have not had a burnt boot yet! I got them through Summit.

steve40th

Jake, please email it to me. corvettesrule@hawaii.rr.com
This is confusing, about the reach, as 2 companies recommended diferent reaches.
Just went to Chamions website and they recommend a RS14Yc6 which has a .708" reach. Now I begin to wonder. I am going to go to the store, and buy one of each with the different reaches and put them in my heads. I have the heads off and will get photos.

DINO

I had a similar problem with #8 , we put a shield that the F-bodies have on there plugs and wah la no problems .

JAKE

Already sent to you and you've already received it. Fast "ain't" I?

You probably already know this, but you've got to choose plugs with the correct reach, thread, hex and heat range, seat type and over-all length.

I've seen heads with .460 reach plugs installed when they should have been .750 and several threads in the heads were exposed to the combustion process.

I've also seen plugs meant for aluminum heads screwed into cast iron jobs. My conclusion: Don't depend on the parts counter guy to give you the correct plugs. Know what you need before you walk in the door.

Just my thoughts.

Jake

Jake

tpi1986

problem is they told me that was with a tappered seat, which the factory alm head is not. Freaking driving me nuts

steve40th

TPI86, Didnt GM have a aluminum head on the Vette and a cast iron head on the Camaro L-98 motors? Maybe they are confused.

tpi1986

Yes that is true alm on the vette from feb 86 on and Iron always on the camaros, but the problem is that the alm head has a 3/4 reach with a non tappered seat. The seat seems to be the big problem. I have found plugs that are short, with the right reach but have a tappered seat.

Believe me, if someone finds one I will be their biggest fan. This entire search has about made me nutz