Inliners International Forums General Discussion Engines My '68 250

Well this project has been a long time coming. I was 10 when I got this truck and now 25 years later I finally have the time and money to work on it. I have had many ideas about what I wanted this truck to be when I was done. Here is where I need your help. If the 250 in this truck is in good enough shape to rebuild I could really use some advise.

I'm at the point now where the engine is out of the truck and on the stand. I have read Leo's inline six book a few times, and I'm reading it again now. I would like to run an aluminum head either the Kirby/Sissel head or if the timing is right the cross flow New Zealand head I have seen on here. With a turbo or supercharger is 400-500hp at the crank really possible and just how well that would that hold together with the right parts. EFI would also be a must.

Now the pictures.
That's me in the back at the age of 10. The same year I got the truck.

And on it's trip home last year.





Now is there anything you see here that I should worry about so far?




Larger images of the last 2 pictures
Front head bolt
Water pump area

Very clean engine on the inside.

STRIP BLOCK AND HEAD COMPLETELY 1ST THING, THEN HOT TANK CLEAN IT ALL UP, THEN CRACK CHECK THE BLOCK AND HEAD, IF ALLS OK THEN MEASURE THE BLOCKS FIRST 2 CYLINDERS AND SEE HOW BAD THERE WORN, THEY WEAR THE MOST AS THEY RUN THE HOTTEST. DONT BE SURPRISED IF YOU NEED TO OVER BORE IT .060 ON FIRST OVERHAUL. ITS COMMON ON THESE ENGINES. IF I MIGHT MAKE A SUGGESTION, INSTALL A 350 V-8 CHEVY. YOU,LL BE GLAD YOU DID IN THE LONG RUN. I HAVE 6 1970-72 CHEVY PICKUPS. BEST TRUCK GM EVER MADE. ALSO LOOKOUT FOR A 71-72 FRONT X-MEMBER ASSY THAT WAY YOU,LL GET 5 LUG PATTERN AND DISC BRAKES ,UPDATE THE REAR AXLE TO 71-72 ALSO FOR 5 LUG BOLT PATTERN.

L6 front cylinders wear fastest because they run coldest - they're the only cylinder to get water directly from the radiator..

Something tells me if he's registered on an inline forum, posting about his inline engine, and plans on spending the money for a crossflow head, he doesn't want a 350...

Yeah the 250 has a lot of sentimental value to me and if I can make it work then I'm going to do what I can to keep it. If it's a lost cause then I will run an LS7 and a blower backed buy a t-56.

So that being said, is 400-500hp with EFI a turbo or supercharger really a something that can be built and hold together.

The build thread on the 67-72 Chevy Truck message board.
Build Thread

So I stripped the engine down today. The amount of crap in the bottom of the pan was shocking. I had fun taking it apart, I have built a few engines before but no inline sixes. Still concerned about the casting of the number 1 hole, pulled the rear frost plug and it looked similar on number 6. Am I freaking out about nothing? Dropped it off at my machinist to get cleaned, check for cracks and let me know how much needs to be cut to get the bores back in shape.






Larger water passage picture:
Big picture

SO WHERE YOU AT ON YOUR 6 REBUILD ?