View previous topic :: View next topic |
Author |
Message |
aaron_sK Member
Joined: 23 Jan 2006 Posts: 8834 Location: Back in beautiful Tacompton
1987 Chevrolet Camaro IROC-Z
|
Posted: Fri May 14, 2010 4:04 pm Post subject: Builders: Please school me on piston dish |
|
|
Or more specifically: How much compression will I lose going to a piston like this:
from a piston like this:
Bore size is 4.052 + .030, stroke is 3.784. Also consider that I am running pretty big heads; 71-74cc IIRC.
Oh and in case you were wondering, yes, I did just buy another big block. |
|
Back to top |
|
|
86toy Member
Joined: 20 Jan 2010 Posts: 61 Location: tacoma
1986 Pontiac Trans Am
|
Posted: Fri May 14, 2010 5:13 pm Post subject: |
|
|
depends on the cc of heads you use .but i would say 8.5 to1 or 9.1 to 1 those are good pistons for a street motor( driver). _________________ 86 t/a 305 tpi 700r4 3.73 possi 4 wheel disc
245/45/17 restoring |
|
Back to top |
|
|
Twilightoptics Hardcore (12sec Club)
Joined: 13 Jan 2004 Posts: 9191 Location: Auburn , WA
1987 Chevrolet Camaro IROC-Z
|
Posted: Fri May 14, 2010 5:23 pm Post subject: |
|
|
They look the same? _________________ A redline a day keeps the carbon away! |
|
Back to top |
|
|
aaron_sK Member
Joined: 23 Jan 2006 Posts: 8834 Location: Back in beautiful Tacompton
1987 Chevrolet Camaro IROC-Z
|
Posted: Fri May 14, 2010 5:29 pm Post subject: |
|
|
The ones in this motor look a lot deeper, and the dish seems a little larger diameter. I'll wait till I pull apart the current block to get a good look at the ones I've been running. |
|
Back to top |
|
|
aaron_sK Member
Joined: 23 Jan 2006 Posts: 8834 Location: Back in beautiful Tacompton
1987 Chevrolet Camaro IROC-Z
|
Posted: Fri May 14, 2010 8:57 pm Post subject: |
|
|
Well crap-dammit. That ruined my day so bad I had to quit, take a shower, and play Forza for a few hours.
Pistons gotta come out regardless. Has the low-pin 410 pistons that Ford put in in later years to get them to run on unleaded and pass emissions. That's 0.128 deck clearance right there kids...
Compression ratio calculator puts the ratio at around 7.6:1 assuming unshaven 74cc heads, 12cc dish on the pistons, and laminate Fel-Pro's.
Fortunately, all I needed out of this deal was the block and the FE bolt-pattern C6, but I was really hoping not to have to pull the rotating assembly out. |
|
Back to top |
|
|
blue89 Member
Joined: 23 May 2006 Posts: 3482 Location: Bellingham/Eugene
1986 Chevrolet Camaro RS
|
|
Back to top |
|
|
|