I need pointers

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straightlinespeed

straightlinespeed

Sometimes I pretend to be normal
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So going to look at a 1980, 360 thats for sale locally. Its in the car and they guy wants whoever is buying it to hear it run, before he pulls it. Its in a 73 roadrunner and he says its a fast engine, and has only had the valve covers off. He said he thinks its cammed, but does not have any documentation. He bought it about 4 years ago, and the only reason he is selling is because he found a 340 for his car.

He is keeping the aftermarket intake but including the factory 4 barrel intake and all accessories, even the carb.

It nice that I can hear it run, and I planned on bringing my compression tester with just to verify all the cylinders are good, but Im not sure what a stock 360 should have for cylinder pressure. What else should I look for?
 
Make sure it holds good oil pressure and doesn't overheat at speed. And check compression if he's agreeable. Not sure wat else you can do.
 
Theres no way Id put a 340 in that B, if I already owned a" fast 360". His loss is your gain.

I disagree with 120psi being a good number. However its about all you get with a used stocker.If all the holes are about the same, then you're Ok.
 
Well, just got back from listening to the engine.

It fired right off which impressed me. It had not been started because I felt the headers prior to firing it. Checked vacuum right away and a steady 15hg. Checked cylinder pressure on the following cylinders. #1-115lbs, #3-115lbs, #2-135lbs, #8-105lbs.

Then engine purred nicely at idle. When revved up it was hard to tell anything between the exhaust leak and the backfiring that was happening, from the exhaust somewhere under the car. He did offer to take me for a ride, but I passed on that.
 
straightlinespeed said:
So going to look at a 1980, 360 thats for sale, but Im not sure what a stock 360 should have for cylinder pressure. What else should I look for?
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My self I would let it come up to temperature if you can, then let your ears be your first tool, after up to temp do a compression test and 120lbs is good, :glasses7:
Myself I say that 360 is a good cast and block to build :color:
 
straightlinespeed said:
Well, just got back from listening to the engine.

It fired right off which impressed me. It had not been started because I felt the headers prior to firing it. Checked vacuum right away and a steady 15hg. Checked cylinder pressure on the following cylinders. #1-115lbs, #3-115lbs, #2-135lbs, #8-105lbs.

Then engine purred nicely at idle. When revved up it was hard to tell anything between the exhaust leak and the backfiring that was happening, from the exhaust somewhere under the car. He did offer to take me for a ride, but I passed on that.
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What's he asking for it....did you buy it?
 
66340SEDAN said:
What's he asking for it....did you buy it?
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I was wondering the same thing :color: if it fired up and did like he said and looking for one :)

Hard to find them running before you buy one :color:
 
$600.00 :banghead: I say walk away and let him try and sell it, then hit him with a $300.00 offer or less for everything :glasses7: JMO.. but I do live in the sticks where these can be bought around my area speed :toothy1:
 
Well, Im thinking that $600 or what ever I spend on it could go towards a completely different engine. Or having mine rebuilt
 
At those compression numbers, I cant imagine it being a fast 360. I think hes pulling it for a reason other than wanting a 340.

A truly "fast 360" will have cylinder pressure over 185, and they will all be even within a few psi. The leakdown will be 4% or less. The closer to zero the better.
A nice peppy 360 will have 165 and 4% to 6%
A useable/cruiser 360, will have 145 and up to 6%.
At less than 120, or over 6%, it is IMO is a core.
Just my 2cents.
Dont jump on me. I've run my 360 at over 200psi, and almost un-measureable LD, and that was a fast motor.It was last set up as 185psi and less than 4%. I have had a couple of 145ers which were only good for cruising.
A tight 318can give a loose 360 a good run, and possibly embarrass the 360-owner.

This one at 115/105/135/115, I would only purchase as a core.$600 is a good start on a freshening.
 
AJ/FormS said:
Theres no way Id put a 340 in that B, if I already owned a" fast 360". His loss is your gain.

I disagree with 120psi being a good number. However its about all you get with a used stocker.If all the holes are about the same, then you're Ok.
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No one said 120 was good.
 
straightlinespeed said:
I didnt buy it. Still thinking about it, but leary of getting into someone elses mess. He was asking $600 for it with the OE intake and manifolds. If I didnt want any of that then he would let it go for less.
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That's stupid high. Cy later tater.
 
Fast, is a point of view. If my car ran in the mid 11's and you asked me if it is fast, my first words are (to anyone who asks) What do you consider fast and I'll let you know. After all, that person may consider 12's fast or 9's fast.

Oh! 340's came stock in those cars so maybe, just maybe, he found a numbers matching (or not) 340 for the car so he can say "Why yes, it is a 340!" Or is it me that it would be impossible to find someone doing that?!?!
 
You're right RRR. You said "anything over 120 is pretty good".
And you are right, for a well-used stocker.

Rumble; I agree with the fast statement.
But the owner said it was a "fast engine" in a 73RR. There is a fast engine,and then there is a fast car.And that lazy engine is in no way," fast". Nor could it possibly have been "fast" in any stock bodied Mopar, never mind the RR.Well it mightabin faster than a lazy /6! lol
 
AJ/FormS said:
At those compression numbers, I cant imagine it being a fast 360. I think hes pulling it for a reason other than wanting a 340.

A truly "fast 360" will have cylinder pressure over 185, and they will all be even within a few psi. The leakdown will be 4% or less. The closer to zero the better.
A nice peppy 360 will have 165 and 4% to 6%
A useable/cruiser 360, will have 145 and up to 6%.
At less than 120, or over 6%, it is IMO is a core.
Just my 2cents.
Dont jump on me. I've run my 360 at over 200psi, and almost un-measureable LD, and that was a fast motor.It was last set up as 185psi and less than 4%. I have had a couple of 145ers which were only good for cruising.
A tight 318can give a loose 360 a good run, and possibly embarrass the 360-owner.

This one at 115/105/135/115, I would only purchase as a core.$600 is a good start on a freshening.
Click to expand...
Why would someone pull a "fast " 360 to replace with a 340 , unless they are going for an original resto . Something is off , 105 - 130 cyl press is not good . Might be good for a rebuild base , but at 150.00 , not 600 .
 
Yep, I agree with all of you. With the numbers all over the place on that engine. Im passing on it!

krazykuda said:
If you want it done right, do it yourself...
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Yep, exactly what Im looking to do, but I've never done it, dont have most of the tools I think I need, so Im a bit nervous.
 
Get yourself a good manual, how to hot rod small block mopars, or something of that nature! They have excellent tips, and pictures. Study it like you're going to take a major test! Then, when you feel confident, take your test. If you run into any problems, you can get more then enough help on here. Better yet, start a thread, then it could be help for anyone else in your shoes. There is no better feeling when that lung comes to life my friend, knowing you did it! Been doing this for 30 plus years and it still gets to me, every time I break in a new motor! Good luck my friend! Shane
 
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