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Pritch Offline OP
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I finally have the money together to sent the twins to the machinist. I have two 292's. I have settled in on a plan. Ultimately, I want to build one supercharged, but I need a motor soon to continue on my project, so my plan is this: I will send both of these blocks in, first to be cleaned and inspected to find out which one is the best one. Then, I will set that one aside for now and build the other one fairly stock to run in my Panel. I am at the point where I need to get the drive train together. Then, as I get more fundage, I will be acquiring parts for the one that will get the blower.

So my first question-the machinist I use is highly recommended and I have had him do my work in the past and I trust him and his skills, but is there anything specific I should have him look for? After inspections, I will have him do all the usual stuff, flatten out the mating surfaces, probably bore each out to the next size ( one has .030 pistons, but the other pistons don't have any oversize markings on them, but they ain't GM, either, so I have no idea what they are.)

Thanks,
pritch

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Its unlikely you will need to prep both engines the same since you have completely different uses for each of them. Beyond a thorough cleanup you will need to have him magnaflux the major core pieces you are going to reuse such as crank, block and head. Sonic checking the block will be a bonus if he has the ability and means to do it. After that, each engine will take a seperate path thru the machine shop as it is being prepped for its specific use to suit your needs. Some machining processes are going to be optional to one, but not the other. Hopefully he can know what they each need to accomplish your goals.



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WITH THESE INLINE ENGINES ALOT OF THE TIME .030 WONT CLEAN UP THE FRONT 2 CYLINDERS AS THEY WEAR MORE BECAUSE OF HEAT. I,VE SEEN THEM HAVE TO GO .060 QUITE OFTEN FIRST OVER BORE....


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I read an article somewhere on restricting water flow to the front cylinder to avoid this problem, but can't find it.
Sound familiar to anyone?

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There is a water Pump GM made that has a plate over the impellor this was to help flow along with the said problem.Personaly not sure if it helped with either.


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I have this pump,, it was a listing for early 70's nova,250 high volume HD use,??? not sure what it meant, but it came nicely polished w/ the impeller plate on the back,,Autozone listed it that way,, I believe its the thorn of my temperature problems,, I think it flows to much thru the 3 core rad, and doesn't allow the time to remove the heat,,,

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fingersix, Please pardon me. Your last sentence does not make sense. Think about it this way: If the water flow results in higher temperature at the radiator exit then that means the entire radiator is hotter. A hotter radiator will transfer more heat to the air, not less. And further, greater water flow through the engine will scrub off the boundary layer and increase heat transfer from engine to water. Greater water flow will increase cooling system capacity.

I'm not saying your pump is or is not the problem, just that "too much flow thru the radiator" is for sure not the problem.

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No problem at all,,, I hate to hijack Pritchs thread, but would love help with this,, this engine should not run hot,, an explanation of my post,, from U.S. Radiator the rads manufacturer,, it is a ultra cool 3 row,,(I forget haw many tubes and fins per inch),,the best recollection from them and my rad shop,, the volume that the rad holds alone does not retain the fluid long enough for the cross flow of air to remove heat effectively,, I tested this with installing another gauge at the bottom rad hose, the other is in the stat.housing, after cruising and getting a constant temp, at Idle it heated up, with the thermostat open the temp between the slowly raised and continued , the temp leaving the rad was no cooler than what went in,,their thought was to install a restrictor in place of the stat to retain the water in the rad longer to allow the air flow time to remove the heat, instead of just dropping it down the tubes with no chance for the cross air to remove the heat form the fluid,,btw,, in the mix I do have a decent 5 blade fan,,, a shroud made, and a seal from the rad support to the hood to stop convecting heat,,still no good, never pops or overheats,, but gets way up there 230ish and burps,, now have overflow bottle,,,

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doesn't allow the time to remove the heat

No such thing.

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Man,,???? I really had myself talked into that theory making sense,,, now what? sorry for the hijack Pritch,,:-0

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All this said and I am no expert. I just want to add something we use to do back in the day when we were runing the old flat head Fords in stock car races was to remove every other vain on the water pumps and this alone made a big difference to control over heating. I have assumed all these years that it just slowed down the flow.Could this just have been a matter of the-revs causing the pump to loose suction ?? .I notice all the new cars/trucks now have a one core radiator and will sit all day in 105 deg. heat with AC on and never over heat...Whats up with all this ???? This cooling stuff is something I would like to understand because I have never been able to wrap my brain around it..!! Jerry


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ol Smokey said "one test is worth a thousand expert opinions."
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If it can not stay in the Radiator long enough It will not cool!!!! Another words If it flows to fast It doesn't get a chance to cool Period.It will cool to a small dergree But Not like it should.Not much different then if your not Getting enough air across the fins of the Radiator To pull the Heat off of it. If it flows to slowly Or not enough air flow over the fins the motor can Over Heat Or run hotter then it should. Greg what Thermosat are you running now?


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Larry, The objective it to cool the engine. Hotter water will tranfer more heat to the air.

"Not enough time to cool the water" sounds like a good argument but it's a common misconception.

If a flow restriction helps to cure an overheating problem the reason is different. One explanation is a flow restriction at the thermostat will cause backpressure in the block which will raise the boiling point of the coolant in the block. This will reduce the tendency for localized boiling. Localized boiling reduces heat transfer because vapor doesn't conduct heat away from the engine block as well as liquid. This is the most likely explanation for observed improved cooling performance by flow restriction.

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Larry,,took the moroso dog dish high flow thing out,,when I was thinking of this flow issue, and now have (thinking) a standard type 190,,I think it had two weep holes in it,,,

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 Originally Posted By: fingersix
a standard type 190,,I think it had two weep holes in it,,,


That is what I would try first.

If you are running a heater, I suggest a restriction to reduce flow thru the heater core. You want it to go thru the radiator. An exception is if you wish to use the heater to help keep your engine cool. That would be a last resort for me!

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 Originally Posted By: strokersix
Larry, The objective it to cool the engine. Hotter water will tranfer more heat to the air.

"Not enough time to cool the water" sounds like a good argument but it's a common misconception.

If a flow restriction helps to cure an overheating problem the reason is different. One explanation is a flow restriction at the thermostat will cause backpressure in the block which will raise the boiling point of the coolant in the block. This will reduce the tendency for localized boiling. Localized boiling reduces heat transfer because vapor doesn't conduct heat away from the engine block as well as liquid. This is the most likely explanation for observed improved cooling performance by flow restriction.


I understand this,But if you can't cool the water your not going to cool the engine either. He has had a hot running issue(well I say running hotter then it should be for a .030 over block)Since he rebuilt.One issue he found was the water heated clifford intake Which was mixing fuel & water.Because of the way they made the intake. The plugs that are in the intake were leaking some how.But anyway that has nothing to do with this at this point. But anyway at some point the Temp should be equal Rad & motor.And he doesn't have this balance.


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I did restrict the heater core once,, It was the first suggestion of the rad shop,, they were penny sized slugs with holes in them, I put at the pipe inlet of the core,, they did nothing different than create eventual seepage at the clamping points after hot temp and driving,,had the intake heat 't' in that line it would blow it right off,switched that to the out of the core,,then took them out,,
I'm getting real close to attempting to remove the steering shaft, which might require removal of the intake and exhaust, if so and I gotta tear down,, I'll switch water pumps,,??

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The only overheating trouble I've had with these engines was the stroker I built with 4.00 bore (.125 oversize) and the cooling jacket filled about 1/3 the way up with Hardblok. Never spewed coolant but clearly ran hot. My latest engine is very similar but with 3.935 (.060) bore, no Hardblok and does not have the overheating problem. I attribute the overheating to the thin cylinder walls. Not sure if that's the true cause or not. An anecdote only, may not apply to your situation.

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Pritch Offline OP
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So anyway, back to my motors...(I don't mind the hi-jack, BTW-a good discussion is well worth it, no matter how it comes about)

I sent then to the machinist about a month ago. I told him I wasn't in a big hurry, so no rush. His shop is near ours, so I have been checking in on them from time to time. Last Wednesday, I stopped by and he told me that they have passed all inspections and are worthy to be re-built. I told him that I have a wish list, and that I would be back Friday to sit down and decide what I could get done for the money I have saved up. He said that he had to close up early on Friday, and I ended up working late anyway, so I didn't stop by.

So last night, I'm sitting home watching the news on TV, and there is a story about a new movie about Ab Jenkins and the Mormon Meteor.

http://www.thefilmyap.com/2011/07/12/boys-of-bonneville-racing-on-a-ribbon-of-salt/

During the news piece, I saw my machinist! Turns out, he's the guy they hired to rebuild the motor in the Mormon Meteor. They were interviewing him at the premier of the movie. That's why he had to close up early yesterday. I've had this guy do work for me in the past, and he comes highly recommended, but now I have an even better feeling about how my 292's are gonna run when he's done with them!

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That's a heck of a movie, saw it at the premier. \:\)


My, what a steep learning curve. Erik II#5155

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