1980ish Mirada build

MiradaMegacab

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Hey can you post exactly what parts and part numbers you bought? I'd love to hear more details about what you did. Been thinking about this too. Thanks!
I don't have access to the part#'s. I tried looking on Diamond Pistons website but had no luck. I used their 2618 forged piston 4.030 with a -30cc dish and 1.55 compression height. Diamond charges $8 per piston to relocate the valve reliefs. The 2616 forging and deep -30cc dish is perfect for boost and results in a 8.5CR. I'm running a 65cc head and 10PSI of boost.
I figured a 3.79 stroke divided by 2= 1.895 + 6.125 rod= 8.02- 9.58 deck height= 1.56 compression height, resulting in the pistons being .010 in the hole.
So pretty much if your using a 3.79 crank, look for a piston with around a 1.56CH.
Using a 6.123 it a longer 6.125 K1 rod will get your deck height close.
 

Shorty Thompson

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I don't have access to the part#'s. I tried looking on Diamond Pistons website but had no luck. I used their 2618 forged piston 4.030 with a -30cc dish and 1.55 compression height. Diamond charges $8 per piston to relocate the valve reliefs. The 2616 forging and deep -30cc dish is perfect for boost and results in a 8.5CR. I'm running a 65cc head and 10PSI of boost.
I figured a 3.79 stroke divided by 2= 1.895 + 6.125 rod= 8.02- 9.58 deck height= 1.56 compression height, resulting in the pistons being .010 in the hole.
So pretty much if your using a 3.79 crank, look for a piston with around a 1.56CH.
Using a 6.123 it a longer 6.125 K1 rod will get your deck height close.

The Silvolite 1278 pistons are flattops . Not to mention that since I'm milling them , they'd be flats anyway. I,,,,,,,, talked alot to my machinist about 50 - 150 shot of NOS . He said WHOA ! Your heading way ,,,,,,,,,into another direction with that , and I'm not gonna lead you down the wrong way to build for this . If ya wanna do that , then we need to recoup and do things way ,,,,,,,, differently . So ,,,,, I'll be happy with the compression ratio of about 9:2 . My heads are stock 340/360 high performance ( supposedly ) for this build . Stock rods , 6.125 , 360 rods . Now I have a set of 5.9 magnum heads , but I still have the magnum they're bolted to as well . Time will tell this summer as to where I'm at .
 

Shorty Thompson

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Update on my motor build, My piston location ;
getPart
 

Shorty Thompson

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Sweet. I just happen to think about it and wondered how it was coming.
Well thanks for remembering ! Son's got the Mirada now. Gave it to him with provisions. 1. if ever decided to get rid of it he had to pay " in full " for it . 2. it had to go to my grand daughter , his oldest , then to his son , the youngest. Right mow he's looking at a 5.9 Magnum build . I'm thinking he's doing a 408 build.
 
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