Olds 307 to Olds 403 engine swap info please?

I hope your inspection goes well. That is one stunnig car:2_thumbs_up_-_anima

 

STP oil treatment may be your answer for the inspection.
2-6 cans of that molasses like lubricant will boost your oil pressure and quiet those tapping noises.......

 

I question whether or not this is a 71 Olds 350? I see a HEI distributor which Olds did not have in 71. Its def an Olds engine from the shape of the valve covers and the oil filler tube though. The 71's were indeed built for the "low leaded" gas being phased in and had what GM called "positive valve rotators" that I guess would extend valve/valve seat life? Good luck on the swap.

 

As far as I can tell it's an original 71 350. The numbers on th heads are correct for 71 and it's a gold painted engine. Sometime in the past the intake, carb, and distributor were updated, along with the valve covers.

We'll see!

-Mike

 

Hi all! Went and paid for my engine over lunch today. Some good, some better, some bad....some new questions....well not too bad.

The bad is only that the engine is still in the '71 Cutlass at the shop. Neill's not had a chance to pull it yet, but since it's 1000 degrees I was not planning on doing much on my car until next month, so it's ok. It should be out next week.

The GOOD is it's paid for and as soon as it's yanked I can pick it up.

The BETTER is I was able to get some new info from the actual owner of the car. The engine was rebuilt about 6 years ago and the car is only a toy, so it does not have a lot of miles on the rebuild. He says it's always run fine since the rebuild, does not smoke ever, and the timing chain and oil pump were done, so I don't have to buy those. Good deal! He said when the engine was built it had some oil leaks and it went back twice to have those fixed, but it ran fine after that, it just was never as fast as he'd hoped so he's wanting a bigger engine.

He says the reason he's yanking was to put a big-block Chevy in the car, but Neill, my friend that owns the shop, convinced him to go with a 403 Olds, to make the swap easy. He was asking $750 for the engine on Craigs List but Neill got me a much better deal, which I'm happy about.

Now the new question, he said when they rebuilt it they put a "mild" aftermarket cam in it for a little more power. It runs smooth, not lopey, but I read if the engine is hopped up much at all it will not be happy working with the 307's computer controls.....so it looks like I may be back to the orignal plan.

We'll see. It's paid for, it's rebuilt, I don't have to clean it in the 100-degree heat this weekend. It's ALL good!

-Mike

 

I ran built 455's off the 307 controls. No problem....except for the AC if it's auto control.

 

Good to hear. I think I'm going to ditch the air pump and AIR hoses but keep everything else. It looks like all I'll need to find is some 80-84 307 exhaust manifolds and even my stock exhaust system will bolt up. Since this is for sure a "budget" swap that'll help.

Will dual it out as funds allow. Right now I just really want to get it running again.

-Mike

 

For the CCC controls, I was sent an interesting page from someone that done the 307 to 455 conversion but kept the ECM.

http://www.robertpowersmotorsports.com/CCC.html

Lots of good info there.....round and round I go!

Sadly the Cutlass the guy had was stolen. That had to hurt. BUT check out his 94 Caprice wagon, also on this page using the links at the top. Love those chrome Silverado wheels on these!

-Mike

 

http://www.robertpowersmotorsports.com/CCC.html



The webpage cannot be displayed

 

http://www.robertpowersmotorsports.com/CCC.html

Hmm...weird. Works for me.

 

The 350 engine is out of the '71 Cutlass. The harmonic balancer has a hairline crack at the crank keyway, Neill found this when we took the components off the front of the engine.



-Mike

 

A crack...before or during the take off.

 

I'm hoping the 307 balancer will fit from my old engine. I'm planning to use all the 307 parts off the front of the engine anyway.

 

Can't you just get an aftermarket replacement damper? Shouldn't be too expensive.

 

Oh I'm sure I can find one new, or used, if needed. This is very much a "budget" build though so I'm hoping the one off the 307 will work.

The 307 was a slug, but if it was still running I would not be doing this swap, the timing is terrible, but the 307 is shot and I'm not going to spend money fixing it, and I'm not letting this Cutlass sit...it's one of my favorite toys. Just trying to bring it back to life at cheaply as possible.

-Mike