WTF?? PI swap ..(mechanically inclined please)

[Tbuck07]

Just called Hi-Tech motorsports, and he told me that I have to use a dye grinder to shave off .25 off teh lip of the piston so theres no PTV issues..he says its not the camshafts that cause it, but when I am to deck the heads..I've NEVER heard of that, he said I could do it with a grinder in my garage. Anyone know what hes talking about here..? Or he said I could do somethign with teh heads in relation to the valves..

The stage 2 camshafts even say no PTV issues..anyone know what hes talking about?

 

[justinschmidt1]

maybe it has something to do with the NPI pistons cause ive never heard of that on a PI motor with those cams

 

[Tbuck07]

perhaps

 

[Tbuck07]

I also need to buy new press on gears right..? The 80 dollar ones..?

 

[topping973]

Could you give a little bit more info on exactly what you are doing? PI swap as in H/C/I with replacing the PI cam with a Stage 2s?

 

[Tbuck07]

heads, cams intake, cams are the hitech stage 2's, decking the heads. I think we got it figured out though.

 

[MustangChris]

how much are you decking the head? thats probably the problem. if your decking it just to zero it out (make it 100% flat, which you should do) i doubt youll have a problem. if youre decking them to raise the compression, you may have PTV problems...

 

[Tbuck07]

I thought if you decked them to be level it raises the compression...

Also, with my cams, Ill have to buy aftermarket cam gears?

Gawd this shit is gonna be like 1500 bucks for the cams, intake, decking heads, gaskets, etc..

 

[DropTopPony]

you don't need aftermarket cam gears, have them grind down the keyway and adjust the gear and tighten it up. Most aftermarket 2V adj cam gears are junk. Sounds like they don't want to or don't know how to time a 2V.

 

[Tbuck07]

Good that saves me another 100 bucks.

But it is a good idea to upgrade your timing chain kit, no?

 

[Red 97]

I was actually going to do the same thing. I thought that ptv happened at the edge of the piston not out were the dish is at.So the only way this would happen if the heads were taken down on the deck. If you run stock pi heads not decked can you run these cams on a npi short block? does anyone know of anyone that are running this setup?

 

[Tbuck07]

From what it sounds like, yes, that is correct. But you almost always want to deck the heads..make sure those bad boys sit right.

 

[MustangChris]

I thought if you decked them to be level it raises the compression...

Also, with my cams, Ill have to buy aftermarket cam gears?

Gawd this shit is gonna be like 1500 bucks for the cams, intake, decking heads, gaskets, etc..

it does, but you shouldnt be taking a whole lot off of the heads to make them level. just a pass or two... decking them means you're taking some SERIOUS head off...

 

[MustangChris]

Good that saves me another 100 bucks.

But it is a good idea to upgrade your timing chain kit, no?

yes. change the chains and tensioners while youre there because they are the first things to go out...

 

[Willis_98GT]

I thought if you decked them to be level it raises the compression...

Also, with my cams, Ill have to buy aftermarket cam gears?

Gawd this shit is gonna be like 1500 bucks for the cams, intake, decking heads, gaskets, etc..

it'll be well worth it

 

[bottlefed97]

I have VT stage 3 cams, and my heads are decked .020, I have no PTV clearance issues whatsoever.