performance pistons

[hasa68mustang]

I havent seen anything on here about pistons lately... but then again I havent spent alot of time on here like I used to. What pistons bolt into our motors? or what will fit if you make em fit . I found out an interesting combo for a d16 civic. aparently suzuki grand vitara pistons bot in and are good for 400 horse... didnt somone use sbc pistons? I remember reading a while back tempo pistons bolt in but I dont think they are good for any more hp.... oops time to goto school...

 

[MustangSix]

Options include:

305 Cheby
Pros: hypereutectic
Cons: 3.763" bore, wrong pin, tall compression distance for a 200

Jeep 258
Pros: forged avaialble, not too expensive
Cons: 3.75" bore, differnt pin

Tempo/Topaz 2.3
Pros: Cheap, correct bore and CD for 200, flat top for more CR
Cons: cast piston, no additional strength

Ford 255 V8
Pros: Cheap, increased CD for 250 applicaitons
Cons: cast, no increase in strength, not for 200's

Buick 3.3 V6
Pros: cheap, short CD allows longer rod in a 200
Cons: Not forged, requires custom rod

 

[addo]

Well, good pistons are made down here. However the price is more than many in the US would be willing to pay. Probably around USD$300 plus freight.

ACL 6MKRY 9410 is a flat-topped hyper
ACL 6MKRY 9411 is an 8cc dish hyper

Both are recommended up to 100HP/litre applications, or a genuine 10 PSI boost. Both can be had with file-fit ring sets.

 

[Does10s]

Well Mike (AZCoupe) sells the JE forgings. They're not cheap but seem to withstand a lot of abuse.
Will

 

[Anonymous]

JE are NOT cheap...but I would trust Mike's parts 100%

 

[wallaka]

I've never heard anything bad about JE pistons, either.

 

[matt1967]

EGGE machine could make you just about anything you want for pistions.

 

[hasa68mustang]

heh the reason I posted this was more of a budget minded piston. I never mentioned that before I Was hoping to find a grand vitara piston for our motors... you know 400 horse for 130 bucks... lol yea the ones mike has would be nice but thats almost as much as I have in the entire motor.... so what would you have to do to modify the pins/rods for the ones if need be?

 

[MustangSix]

to use the 305 pistons you would have to open the small end of the rod to accept the chevy pin, then you would have to machine the top of piston to reduce the CD.

by the time you bought the chevy pistons and got all the machine work done, you may be close to what a forged set would cost.

 

[powerband]

An interesting option noted by 'Stang6 is the AMC - 258cid pistons. The higher "Compression Height" - addresses deck height and the relief in the top of the Piston keeps CR in check while giving clearance for the valves.

Discussion - more info - http://fordsix.com/forum/viewtopic.php? ... highlight=

Excerpt from a discussion of this:

"CZLN6 / Mod Squad Member:
Posted: Tue Jun 06, 2006:

... on the Silvolite website and found a similiar piston. It is part #2227. They list the cc volume of the recess at 21ccs- which makes it ideal for this application. It lists the depth of the recess at .185".

With the .070" overbore the bore is 3.75", stroke of 3.91, a Felpro head gasket at .050", a zero deck height, chamber volume of 60ccs and a piston recess of 21 ccs, gives an ideal street compression ratio of 8.8:1!!!

And, the recess is not "D" shaped, but appears to more closely mirror the shape of the combustion chamber of a small ford six. The dish is more of a bathtub shape.
".


This engine built in Jack Clifford's shop years ago, continues to perform flawlessly with a Torquey midrange powerband and an even power range all through RPM's. I found casting numbers on the top of the pistons to be STD - 470NP. What I discovered is the pistons are likely to be TRW/SealedPower # 470NP's. The application is 79-89 AMC 4.2(258).

Jack Clifford, legendary six cylinder racer, record holder and engine builder's shop, performance built Ford 250 six engine- 10:1 Pistons, Clifford rods, Clifford 272H Cam, line bored & balanced bottom end, Cloyes timing set, Fisher balancer, 1.88 int. valves, Ported and relieved, Offy 3X1 w/3 Holleys, Re-curved distrib., the works, a few mysteries...

 

[AzCoupe]

Last December, when we were at PRI, we made some contacts in Argentina. Since then, we have been working to set up acounts with some of the AR manufacturers. Iapel makes Forged pistons and the quality is as good as any found here in the USA, maybe better. They only make 40 and 60 over, but have agreed to do other sizes for us if we order in minimum quantities. As well as any custom spec piston we want, as long as we order the minimum. Prices are reasonable, so we just need to figure out a cheap way to ship them (thats the killer). But we are working on it.

 

[hasa68mustang]

8.8 is a bit high for a turbo motor isnt it? The added cubes could help a bit also. I was hoping to get something that would add some strength to the rotating assembly with some cheaper items... that basically is what my build was about. but now its turning into a money pit... but still nothing too expensive... Mike thats great news... this inline 6 thing is getting pretty big!

 

[80Stang]

How about the following Chevy pistons for 250:

STL-534NP (Speed Pro)
bore: 3.736, cast
Flat-top w/4 valve reliefs 5cc total
Compression distance 1.540
$11.99 each

STL-H534CP (Speed Pro)
bore: 3.736, hyper
Flat-top w/4 valve reliefs 5cc total
Compression distance 1.560
Low-friction coated skirt
$16.39 each

TRW-L2486F (Speed Pro)
FORGED
bore: 3.736, forged
Flat-top w/4 valve reliefs 6cc total
Compression distance 1.560
Low-friction coated skirt (?)
$42.95 each

All have 0.927 pins, so that needs be adjusted at the rod.

 

[Anonymous]

heh the reason I posted this was more of a budget minded piston.

I wouldn't buy more piston than you really need.

8.8 is a bit high for a turbo motor isnt it?

Not necessarily.

 

[Anlushac11]

8.8 is a bit high for a turbo motor isnt it? The added cubes could help a bit also. I was hoping to get something that would add some strength to the rotating assembly with some cheaper items... that basically is what my build was about. but now its turning into a money pit... but still nothing too expensive... Mike thats great news... this inline 6 thing is getting pretty big!

Thats not too bad. The 79-81 carb turbo Mustangs used a 9.0:CR forged flattop.

The Mustang Turbo 2.3L EFI turbos IIRC used mostly 8.5:1CR

If your CR is too low you have problems building power to get boost started.