Set of PI heads, one 4thread and the other is 8thread...

Tally_4.6

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The set of PI heads i currently have work getting work done to are mismatched, i discovered last week that one is an 8thread head while the other is a 4thread head.

Has anyone ever encountered this?

Point being, obviously i don't have to worry about the 8thread one. But while they're out should i just helicoil all 4 plugholes in that head?
 

kb1982

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I would say yes, definitely be proactive and install them now.
 

96blak54

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Dump the 4thread head. Dont repair it. You kill performance potential installing a metal insert wraped around the plug.

What work are you getting done?
 
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Tally_4.6

Tally_4.6

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Light pNp, 5angle, bowl blending.

Easier sais than done, but how the hell am I gonna find a lone 8thread PI head?

You can't tell me anytime anyone has ever had this issue they rip off the head, or heads and go lookin for some 8thread heads.

Sent from tha trap house.
 

D3VST8R96GT

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You want lock and stitch aluminum inserts. Where most people go wrong is getting a) helicoils and b) inserts that are steel or stainless steel. While it may be stronger the heat conduction is important from a performance standpoint.

Yes they could have been mismatched in a car if one replaced under warranty by ford after 03ish. Seen it in trucks I wouldn't doubt it happened in cars.
 

96blak54

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05-up crownvics, E250, E350 vans and 2valve F250, F350 all come 8thread.

Ask me why I wouldnt port or bowl blend. Also let me know what cam your going with
 

J_Sty_

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Light pNp, 5angle, bowl blending.

Easier sais than done, but how the hell am I gonna find a lone 8thread PI head?

You can't tell me anytime anyone has ever had this issue they rip off the head, or heads and go lookin for some 8thread heads.

Sent from tha trap house.

Maybe the one good one on the motor in the black car is 8thread...
 
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Tally_4.6

Tally_4.6

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You want lock and stitch aluminum inserts. Where most people go wrong is getting a) helicoils and b) inserts that are steel or stainless steel. While it may be stronger the heat conduction is important from a performance standpoint.

Yes they could have been mismatched in a car if one replaced under warranty by ford after 03ish. Seen it in trucks I wouldn't doubt it happened in cars.

http://www.locknstitch.com/Products.htm

That?
 

D3VST8R96GT

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Yeah that's the place.... the first website is from 1998 Lol....

The 2nd is from 2005. Hit the contact us and see if they have machine shops they refer out too. I just happened to find one by asking the ford dealer down the road when my buddy launched his plug
 

96blak54

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The locknstitch is Ford TSB approved replacement...only! The locknstich is aluminum allowing excellent transfer of heat from the sparkplug, were as a steel helicoil or timesert creates more hotspots in the chamber and holds the heat in the plug.

Like ive stated, if youre staying low compression, youll be fine using a steel insert.

The locknstich requires special tooling and so does the timesert, but the helicoil does not. Locknstitch & timesert tooling with the inserts touch $500. Or find a service rep with the tooling and pay them $100 for the work.
 
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Tally_4.6

Tally_4.6

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Doing my best to stay low compression. Tuned NA at first, then boost later.

According to my loose calculations, i wanna say around 8.7:1

'03 GT block and crank
Boss rods
-18cc Manley forged pistons
Lightly ported PI heads
Comp 270s
Comp springs & retainers
37# injectors
 
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Tally_4.6

Tally_4.6

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No good?

Like I said, loose calculations. Fairly sure I got the right specs, using a couple different sites.

Sent from tha trap house.
 
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Tally_4.6

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Too late either way.

But a helicoil should be ok to install?

Sent from tha trap house.
 

96blak54

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You wont like it. They back out. Un like timeserts, their are alot of timesert installers out there. Even I have a kit. Search a few local auto repair shops. One of them bound to have a set.
 

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