Inliners International Forums General Discussion Engines New guy Swapping 350 for 250

I just joined up, I bought my 71 Stepside in Dec:



I have been trying hard to get fully road worthy ever since, it ran great except on the freeway it clattered like crazy. I've always wanted an inline 6 again, and when I found out my 350 had a spun bearing, I decided I was going to go for it.



I found a good used 250 from a 73 Nova online Saturday morning, and by the end of the day, I had come home with a new engine!



A guy called about the 350 that same afternoon and he came by that night and we pulled it out, and now it's gone! I am very happy at the rate this is going...



A guy from the 67-72 board is sending me the motor mount brackets I need and I bought all the other parts I am going to need today, so the rest of the week will be cleaning and painting and changing gaskets etc. I am very excited to be driving a really cool truck with good gas mileage with lots of upgrade potential. Alot of people are looking at me like I am crazy for replacing a 350 with a 250... I just smile :p

Don't really have any questions as yet, just wanted to say hello, and I guess I am looking for a power steering bracket... That's the one thing I am lacking... Great group!

Welcome aboard, nice looking truck. I'm thinking about doing the same with my 68 C20, except using a 292. You came to the right when you get ready to mod that six.

Larry

Good luck with your "backwards" conversion. The truck will drive great with the 250 and with the right exhaust make some much cooler sounds...

Welcome aboard. Love those 67 - 72 short beds!
The 250 looks like it may have been recently rebuilt judging by the color and condition of the head and block. Good for you.

Welcome! I'm over on the other board too under the same name.

Looking good & Welcome to the Inliners World Of Buzzing fun

Hey guys, I am all done and trying to start this bad boy but apparently having timing issues, I am getting spark to the plugs and gas to the carb just fine, so I figure it is the distributor stab stuff.

I double checked that TDC is on the #1 (manually turn and rag method) it ended up just before the timing marker, I manually pulled it over the couple of inches to 12 before TDC and stabbed the dist pointing to the #1 plug wire. Tried starting it and it backfires through the exhaust.

Pulled the cap and bumped the starter so the rotor is 180 degrees opposite from the #1, again the timing mark was sitting just before the tab and manually pulled it up to about 12 BTDC then pulled the dist, and restabbed it to the #1 position. Now it doesn't back fire through the exhaust at all but spits (not backfires) through the carb. I ran through the whole range around where the rotor would be hitting the #1 wire on the cap and it acts like it is too advanced (compression seizing).

Any ideas? I feel like the stab is right this time but I could be wrong. Which is closer? spitting through the carb or the exhaust? haha I didn't try the whole range of timing locations in the first position because I figured backfiring was bad.

Here's a pic of the finished product

Houston, we have ignition! Apparently I had it stabbed right the first time yesterday when I first put the dist in, it backfired so I immediately spun it 180, but I didn't try different timing locations first. Today, I double checked TDC and it was right on, so I put it 180 back to the original location and it started up after a little tweaking of the dist. That's a goood sound.

It runs smooth as silk but the carb is messed up. It is leaking, and I saw that the base was busted on the mount, and the throttle won't seem to set all the way down even with extra springs, so I think this new engine deserves a new carburetor. I am going to pick one up tomorrow if the auto parts stores are open and I should be on the road.

I also went to the junkyard today and picked up a gearshift bar that goes from the column to the side of the tranny, mine was too short after I moved everything back. I also got a speedo cable that was too short for the same reason and an oil pressure sending unit adapter that goes into the block that I forgot to pull off the 350 when I sold it.