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I know the PTV clearance is close using VT Stage 2 NA cams on a PI motor. I dont have a 96-98 shortblock around to take measurements, wish I did so I can mock it up. But is anyone running PI heads on a 96-98 shortblock with VT stage2 NA cams? If so did you have an PTV clearance issues using stock headgaskets or will it even work at all?

Dave
 

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It shouldn't affect PTV at all. The problems with PI motors have more clearance inssues that NPI motors are the valves. The PI valve have a rather large lip on them, taking up needed space for bigger cams. It doesn't matter on a 2V if the piston is dished or not...the valve is so close to the outside edge of the bore that it smacks the outside of the piston near the edge, at that point the dish is non exsistant.

So to answer your question...It will work if you degree them in and put them in with the proper clearance.

hope this helps...
 

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I use an 01 Cobra short block with -2.3CC dish piston and VT Stage II cams.......no PTV issues.....and use the Patriot Stage II heads with the 1.78 valves.......just pay close attention and you will be fine.....

"ED"
 

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Its a bone stock 01 Cobra Short block.......had only 20,000 miles on it......the car it was pulled from was just featured in mm&ff's.....in Honor her........a yellow 01 cobra wild build that made almost 700hp.......picked it up for 800.00.......thats why if anyone wants to do a cheap strong N/A build their best bet is an aluminum stock Cobra block or Mark VIII........comes with -2.3 CC dish pistons that will raise your CR with a ported head ...roughly 44-48CC's You can run between a 10.8 to 11.5 CR.......the VT Stage II's fit perfect in there.......No PTV issues.......and add's close to 8 to 9% more power with the bump in CR........plus having the forged crank and aftermarket heads with cams.....it is RPM Friendly like the 4V's are........6500 RPM's safely all day. Plus saving 75 lbs off the front helps...!!!

"ED"
 

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^ Um...you better look again.

The 01 motors aren't ANY stronger than any other GT motor out there, save for the crank. But who cares about the crank when the rods will give at 400-450rwhp. If they were running 700hp on a stock 01 Cobra block...they weren't going to do it for long.

And like I said above...flattop or not it doesn't matter. The valve will hit the outside edge of the piston where the dish doesn't matter anyway.
 

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I have Patriot performance cams laying around that came with my car when i bought it. Will these cams have any problems with this set up.. i have a 99 cobra bottom end with pi heads. The cam specs are as per Patriots website 233/237 .545"/.550" 113 lsa.
 

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^ Um...you better look again.

The 01 motors aren't ANY stronger than any other GT motor out there, save for the crank. But who cares about the crank when the rods will give at 400-450rwhp. If they were running 700hp on a stock 01 Cobra block...they weren't going to do it for long.

And like I said above...flattop or not it doesn't matter. The valve will hit the outside edge of the piston where the dish doesn't matter anyway.
Never said the motor was stronger......and the car didn't use the block either.....I purchased the block because he put in a 5.1 stroker kits....(new engine).......The 1.78 valve that almost every stage II heads come with will work within the stock walls with the right cams.....its the 1.84 valve that wont........you will need an overbore at that point.......and if you can hit 400 N/A with this block.....I think it will live forvever compared to the stress that forced induction puts on a supercharged 400 hp car......

"ED"
 

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Its a bone stock 01 Cobra Short block.......had only 20,000 miles on it......the car it was pulled from was just featured in mm&ff's.....in Honor her........a yellow 01 cobra wild build that made almost 700hp.......picked it up for 800.00.......thats why if anyone wants to do a cheap strong N/A build their best bet is an aluminum stock Cobra block or Mark VIII........comes with -2.3 CC dish pistons that will raise your CR with a ported head ...roughly 44-48CC's You can run between a 10.8 to 11.5 CR.......the VT Stage II's fit perfect in there.......No PTV issues.......and add's close to 8 to 9% more power with the bump in CR........plus having the forged crank and aftermarket heads with cams.....it is RPM Friendly like the 4V's are........6500 RPM's safely all day. Plus saving 75 lbs off the front helps...!!!

"ED"
You just tried to make a point for a cheap build use this block...its a strong N/A build. It is NO stronger than the GT motors. Just more compression. Now if you meant 'strong
like makes more power I understand.

I had +1mm valves in my N/A 2V build...it did have a .020 over bore...but that still doesn't have much to do with PTV when talking about piston dish....
 

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You just tried to make a point for a cheap build use this block...its a strong N/A build. It is NO stronger than the GT motors. Just more compression. Now if you meant 'strong
like makes more power I understand.

I had +1mm valves in my N/A 2V build...it did have a .020 over bore...but that still doesn't have much to do with PTV when talking about piston dish....
That is pretty much what I meant........its an easy way to get the most out of a stock block N/A build......not saying the engine is stronger by any means......but it should be more rpm friendly than a stock gt block....the cobra's red line is close to 6500...no..??? Thought that was because of the cam design and forged crank.......now if the 2V has after market heads and higher reving cams the engine should be good at 6300-6500 rpm shift points......since the aftermarket valve train and springs can support it......as far as OEM pistons........the edges of the pistons are the same...just the dish size is different......if a peticular cam works on a -18cc dish it should work on a -2.3cc dish.....thats at least what my engine builder told me........its the edge of the pistons and walls that mostly come in contact depending on how eggressive the cam profile is............flat tops were said to be a different story.........

"ED"
 
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