|
|
|
|
Original Message
|
| 390 truck vs 410 pistons |
| By Paul Garvin - 10/30/2002 4:38:20 PM; IP 65.105.39.2 |
I finally got around to begin seriously working on the FE I am building for my 69 XR7 Convertible. The motor is a D4TE 390 truck motor that was in the F250 that I recently got rid of.
I pulled the pistons/rods and numbered them as I went so that the rods would go back in the same bores. I noticed when I pulled the pistons out the only markings on the pistons were the number 410 next to the piston pin holes. I cannot find any part number on the crankshaft although it is still in the block. I have done a number of forum searches on 410 and truck 390's and I am getting the impression that the pistons may be the same. However, the piston seems to sit pretty high in the bore. Would a 390 truck piston be low in the bore to reduce compression?
Is it possible that at some point this motor was rebuilt and 410 pistons were used. I bought the truck from my brother-in-law and he said it had recently been rebuilt. I put about 30K miles on before pulling the motor. The pistons look to be in very good shape with no wear or scuffing. And the cylinders are in very good shape as well with little or no ridge, and no scratches.
I have a 1UB CJ crankshaft that I was planning to use to build a 390 stroked to somewhere between 410 and 428. The engine had good compression before teardown, but I thought I would have to replace the pistons if I went with the 1UB crank. Is it possible to use these pistons? Is it a good idea to reuse them? Is there a wear limit that I can measure with a micrometer to help me make the determination.
If all the parts are in good shape and measure OK with a mic, can I simply have the block honed, the rotating assembly balanced, and just replace the rings and bearings? That would make this whole project a lot simpler and would move my time table way up.
Sorry for the long post, and thanks in advance for all your help.
Paul G.
|
|
|
This thread, so far...
|
|
|
|
Post A Response
|
|
|
|
|
|