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Sorry bud, but that old 289 is plain worn out!Looking for suggestions on upgrades please.
(and apologies - i know this question will have been asked several times in similar fashion)
I have a fairly stock 289, which is still getting hot on the passenger side. I've got the citric acid flush left to try, but pretty sure i've narrowed it down to being related just to that head (whether the passages are all blocked up or something). Judging by the oil condition when i got the car, i dont think the PO was that into changing fluids. :/
Oil pressure is also quite low when hot - at idle, the needle is barely lifted off the stop. It's about 1/4 way up the gauge when cruising, and 3/4 of the gauge when cold and first started.
So, im thinking some worn bearing shells probably cause of this. No knocking, but thinking still due a rebuild. Also, get a reasonable amount of breathing out the rocker cover filter.
So, thoughts while i'm at it, is that maybe just replacing the heads is the way to go.
Current specs are:
Stock 289, with Edelbrock Performer intake, and Edelbrock AVS2 500 CFM carb. "High rev" hydraulic lifters, uprated springs (inner & outer), new Cloyes timing set, and changed the cam (which was meant to be a Performer, but got something different - but is about 1-2 levels above stock). Standard exhaust headers, with 2" dual exhaust. Stock C4 trans, and stock rear axle/diff.
Not after anything too fancy - just street use for a bit of fun, and a bit more noise/choppier idle.
After suggestions, please, for suggested mods? I.e. new heads (or should i just strip and completely refurb my stock heads?), plus cam (i'm not against changing this again), and others?
I'm allowing for crank grind, new bearing shells, cylinder bore hone (probably), and set of rings (hopefully dont need new pistons), new oil pump. Would i need new push rods?
And ideally, i guess i should change stock headers (and hopefully could just change the headers and adapt my current dual exhaust to mate up to the new ones).
Probably budgeting around 2500. I know heads would eat quite a lot of this, hence the question about refurbing current heads. But if i'm wasting my time doing anything else until the heads are changed, then maybe budget needs to increase a bit..
Any thoughts/suggestions greatly appreciated.
Many thanks in advance.
It needs a complete rebuild. $2,500 is barley going to get U started!
On the stock heads, there are small coolent passages that run around each spark plug. I found this on a set of 1970, 351W iron heads. They were all clogged shut with sediment and rust. I worked at clearing those passages out and over a perion of a week or 2, I got them all opened up. Hot tanking would never have worked on this. I bent a series of nail sizes into a "U", and drove them with a hammer to clear those spark plug cooling passages. Once I got the passages opened up to about 1/8th inch in diameter, I finished the cleaning with a very small flexable round elongated wire brush, mounted on an electric drill.
If you look into the coolent passages of the heads with a lite, you may find some thin-walled casting flash that you can break out with a hammer and a screwdriver. This flash acts as a flow barrier. You don't have to get every little bit, just the majority of it and you don't have to be neat about it. That will increase your flow.
Overall, there is so much you could do, $2,500 will just get U started. But, from what U said about the breather belching fumes, the rings are shot and the oil pump has seen better days, And don't be surprised to find a particially blocked oil pick-up screen.