Apparently JE has obsoleted the piston most of us run, the 8.8 (or 8.6 if you believe Howell).
Also apparently Howell now ships a DOMED piston??? wtf?

OLD JE P/N: 168612
NEW JE P/N: 208476

OLD JE Dish Depth: .020
Howell Dish Height: .120

Old JE Groove Top: .048 2nd: .048
Howell Groove Top: .060 2nd: .060

Old JE Weight: 338 grams
New JE Weight: 339 grams

New JE Piston: http://www.sportcompactwarehouse.com/PROD/JE208476

New JE Specs: http://www.sportcompactwarehouse.com/jepistons/apps.html

Old JE Specs: http://tinyurl.com/2zu5t

Howell Piston: http://www.howellautomotive.com/Howell/Store/catalog/catalog/product_info.php?cPath=142_38_84&products_id=1339

I called JE and they said the new piston COULD NOT be used as a replacement for an old one, without replacing all 4. He claimed the new part number is "about 30 grams lighter" than the old one, even though that website shows it as 1 gram heavier. They still have the old number on their website.

Question 1) Is Howell's domed piston a misprint/typo?

Question 2) Can I use 1 new one with my 3 good old ones?

i'd call howell, 99% sure they'll steer you down the right path.
_________
96 talon esi-t
san clemente, ca

as needles of ice
are the ill winds' talons
the coldest of shadows
they seep unto the bone

Like you told me once , I would stick with similar pistons for balance issues, that and if the dimensions are a bit different then why mix things up?

Originally posted by thedawg
Question 1) Is Howell's domed piston a misprint/typo?

To my knowledge, convex or concave shaped piston heads, otherwise known as vortex (?) create a swirling motion of the air/fuel mixture as they move, thus creating a better mix. Supposedly when they came out with this discovery and took it to the track, they had to make a separate class for the cars with the vortex pistons because it made such a difference. Hope this helps....I myself have been looking for some for awhile.

generally speaking for our cars

dished are turbo (have to remove material to provide more room for air and fuel)

domed and generally hi compression 10.5:1 +
usually 12.5:1

Originally posted by weepulTo my knowledge, convex or concave shaped piston heads, otherwise known as vortex (?) create a swirling motion of the air/fuel mixture as they move, thus creating a better mix. Supposedly when they came out with this discovery and took it to the track, they had to make a separate class for the cars with the vortex pistons because it made such a difference.

You win.

I couldn't resist either...WTF is a Vortex piston.....

haha, I didn't make that shit up! =) Was what they told us in the army when I was training to be a mechanic. Not sure what the piston is called exactly, but it would force the air/fuel into a vortex (swirl) in the cylinder and mix it better.

Originally posted by weepul
Was what they told us in the army when I was training to be a mechanic.

That was your first freakin mistake right there....beleiving anything the army tells you!!!!!
they once gave me 60lbs and told me to walk a few miles down hill. it turned out to be 90lbs and 15 miles mostly up hill....

owned by the army ^^