so my 307 is not long for this earth

[86Olds442]

So after doing so much to my 86 442 its now telling me that I need to rebuild or replace her heart. I have ridiculously low oil pressure after driving her about 25 miles. I'm sure the bottom end is tired. Sad, only 118k on it. So this is surely not in my 2010 budget, but I'm looking at what to do with this. I hate the idea of rebuilding a 307. Thinking olds 350 or 403. Thoughts? Ideas? What should I look for or stay away from? I've never had a 307 fail before, so this is kinda new to me. Would like to keep it all olds though. No chevys under the hood. Would just like to have more pep without eating up much more gas. Thanks guys.

 

[dan2286]

A 350 or 403 would be the easiest swap and won't cost anymore than rebuilding the 307. Just try not to hack everything up like a lot of people do. If you do not plan on using the computer system, tie the harness off to the side instead of cutting it off. There should be no reason to change anything else as long as you swap everything over from the 307. It may be a good idea to save the 307 in case you decide to sell the car and someone wants to use the original engine.

 

[gpguy]

Rebuild 307 these are getting rare,all getting cut up originals are where the money is jmo

 

[RITTER]

I agree, keeping it original is kind of cool. You can have the heads redone and port/polish and put a nice cam in it and have some decent power, maybe even go as far as putting a little boost on it. Or just throw a rebuilt 350 Olds in there and just tell people that it is still a 307 :lol:

 

[Minion1186]

you have the HO version of the 307,correct?Even its its underpowered and tired,i would still hold on to that VIN 9 powertrain,could still be worth something,especially the valvetrain,modified ccc carburetor and that dual snorkel air cleaner with the chrome lid.I have always nodded towards a 350 olds,i'll be running a 400 horse one come febuary.the 403 isnt all a bad choice either,but the tend to have weak bottom ends and if you ever plan on a 403,please look into getting a halo girdle for the bottom end,strengthens the weak portion of that engine,here's a link for the girdles-http://mondellotwister.com/EngineBlock.htm.Aside from that modification to the 403,both the 403 and 350 can make serious power with a little work put into them,if you have time,look for a good pair of SBO heads,like the #7 (W-31) heads.I have a pair of those on the 350 i just bought,the feature larger valves (2.000),64 cc chambers,the pair i have are fully ported with any heart passages filled in to better cool the intake.In my opinion either one of these engines are worth getting,both like i said can be powerhouses and if worked right can make as much horses as a big block,possibly even more.If your looking for a good 350,i have one i'm selling,its a 73 350 complete but needs a rebuild-$100.BTW,speaking of rebuilding a 307,I have my 307 from my cutlass salon,its the VIN Y version,it was rebuilt,bored .40 over,port matched heads,rebuilt ccc carb and had stock exhaust,it made about somewhere north of 200 horsepower/250 ft/ib torque and was a true 313 cubic inches.I also have this one,doubt anyone wants it,and i might just keep it around.

 

[84 W40]

I agree with the last post. Look for a 68 to 76 OLDS 350 block there stronger , heads # 5,6,or7 there the best heads and all the brackets from your 307 will fit on a olds 350. Bag the 307 and save it thats what i will be doing this year with my H/O engine and it only has 44k on it and droping a 1970 olds 350 with # 6 heads.

 

[olds307 and 403]

The vin 9 tend to blow up much more often than the regular vin y. I think the much deeper gearing and shift points do them in. The 350 Olds is a very durable engine, even one with #8 heads and Probe flattops would dust your 307.

 

[86Olds442]

Thanks for all of the input guys. Great ideas and put lots of thoughts in my head. My biggest issue is that currently, I have no real place to store the 307 if I opt for something else. That is where I'm stuck. I want to keeo this motor around because it is a numbers matching car currently. I think regarless of what I'd like to do, I'm going to be stuck rebuilding the 307 thats in it, and in a couple of years look to upgrade. My next house will again have a garage for me to do work like this, and a place to store that engine. Now, what can I do to give this 307 some more life? Ideas? Thanks.

 

[Blake442]

I'd look into what's causing the loss of oil pressure. As long as it hasn't already started to knock...
Is it really an oil pump, or is it a failing sender, or the notoriously inaccurate gauges?

My H.O. 307 let go at around 118K miles as well, but mine over-revved and broke a rod cap loose...

 

[86Olds442]

I'd look into what's causing the loss of oil pressure. As long as it hasn't already started to knock...
Is it really an oil pump, or is it a failing sender, or the notoriously inaccurate gauges?

My H.O. 307 let go at around 118K miles as well, but mine over-revved and broke a rod cap loose...

I have only recently actually gotten to drive this car since I got it two years ago. I think I have put 300 or 400 hundred miles on it myself. I get about 45 psi full cold on the gauge, and about 28 psi driving, and about 15 psi idling. This has been the norm, and acceptable enough. Then when driving her around alot yesterday on the highway, starting hearing the tapping of the lifters. Got off of the highway and watched my needle sit right on the lovely red area of the gauge, and even sit at zero with no movement for a second or two. It runs excellen and strong, quiet, with no bearing noises or whatever.I totally realize this is an innacurate gauge, so I am replacing the sending unit tomorrow, changing the oil from the 10w30 in it to 10w40. I'm hoping to save this motor from needing a rebuild. I would rather build a better 350 later. I'm not sure that this will buy me that muc time, but we'll see. It needs an oil pan gasket anyway, so I guess I can take a good look inside when I do that - When it warms up!