Well, it's my turn to ask for suggestions..

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318willrun

318willrun

Utube channel 318willrun
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I will do my best to keep this short and to point. Please read all that I wrote so I don't have to repeat, thanks. I installed the "new" 360 in my Duster.

The engine: 360 "parts store crate motor" from craigslist never fired. Bought from the guy that got it from his friend on a trade. I pulled the oil pan, valve covers, intake, and it truly is new. I saw new pistons, oil pump, head bolts, valve springs, etc. It truly was never fired. Guy was going to install it in a RatRod, so he added dual quads and a H260 cam. I sold the dual quad intake, connecting gears, shorty headers leaving me with a new motor for 400 bucks. I put a Weiand action plus/600 eddy all from my great running belvedere, and a new double roller timing chain. Full advanced timing for initial drive was 36*, and idled at 13*. Stall is the 318 original (balanced flex plate) with 904.

The problem: Installed and did the cam break-in. After that, a short run around the block revealed absolutely no power. I mean, the 318 2bbl had way more power. It will barely cross the street!!!!! Starts right up and idles pretty good.

what I've tried so far: Checked firing order, ok. Checked compression, 170 psi (new snap on compression tester). Different dizzy, new ballast resistor, went over all the grounds, backed the timing off to 32* full advanced, then up to 42* full advance. Tried a different carb (770 street avenger). Most of the stuff being used ran great on the 318 in my belvedere (carb, dizzy). New plugs and wires. Pulled the plug wires off on by one while idling, and they all dived the motor down a tab.

What's left: If I didn't get the dots on the timing chain lined up (I've never messed one up in my life), is this how it would respond? If I did knock a cam lobe at break in, is this how it would respond? Any suggestions??? Did I miss the obvious???
 
What cam is in it? Brand, part no? I don't know what H260 is

I would absolutely suspect cam timing, or maybe even "bad cam choice". It MAY be not as obvious and "off" "dot to dot". There is considerable difference in cam timing caused by manufacturing tolerance, which is exactly why advance/ retard cam drives are sold.

You can check cam timing "to some degree" right in the engine, but first you need to know what the cam specs ARE and you'll need a degree wheel and dial indicator with enough travel (IMPORTANT!!) to follow valve movement.

You can also estimate cam timing for a "quick check" if you know the intake closing event, because this happens near TDC.

Google "how to degree a cam" you'll find all kinds of help, articles, videos.

https://www.google.com/search?num=2....0....0...1c.1.64.serp..2.23.1389.5zagH5zSUdE

http://www.lunatipower.com/Tech/Cams/HowToDegreeACam.aspx

[ame="https://www.youtube.com/watch?v=7cNoVRLb73c"]Quick Tech Video: How to Degree Your COMP Cams® Camshaft - YouTube[/ame]
 
I might suggest the first step is to remove the valve covers and check your valve action. If you lost a cam lobe, you will notice little to no lift on that cylinder. Drain your oil and check for metal filings before you do that.
 
With 170 crank compression I'll assume cam lobes and cam timing are good. Get the initial timing bumped up to at least 16, 18 and more if the motor responds. Do the normal initial timing set with max vacuum at idle followed by heat soak to check starter kickback.
Recurve dizzy then screw with a fuel curve.
What is your vacuum at idle?
 
What makes you think its the motor? 260 high energy cam is mild. Most cams dot to dot run fine too. Possibly a trans issue?
 
Are you just used to a fast car ? I get in a 15 sec car and it feels like I can keep it floored for days and it's not moving . Is it really that dead ?
 
Check fuel pressure ?

Even if the cam was severely retarded would think it would move better than your saying, my 400 bronco come factory severely retarded, apparently a after market chain is worth 10-20 hp on it but it still had balls for what it was.
 
A) Check TDC on balancer vs real TDC using a piston stop. Aftermarket balancers are seldom marked correctly.
B) Once you know that's right, it would probably pay to check the cam timing (degree the cam). Aftermarket timing sets, and camshafts are often not marked correctly or are just manufactured incorrectly. If you don't know this is put together right, you could be chasing your tail forever.
C) Then, and only then, can you start messing with timing. You want at least 14° at idle and about 34° all in by about 2500. Then you can fine tune the vacuum advance, if you have it.
D) Obviously, if the carb and rest of the fuel system worked before, I'd assume it was still O.K. so that would be the last place I'd look.
 
jerry6 said:
Are you just used to a fast car ? I get in a 15 sec car and it feels like I can keep it floored for days and it's not moving . Is it really that dead ?
Click to expand...
yes, but this car would probably turn a 20 second E.T. as she sits. My 3/4 ton Ram that ran 16.7's would toast it. It start's right up, and idles pretty good, just won't pull itself out from a gas station. When the engine was on the stand, I had #1 piston up, and the harmonic balancer timing mark showed 0 (TDC). I don't know the make of cam or specs, as it was in the motor when I bought it. I pulled it to read the markings, and it said H260. It had purple paint on the end between the last few lobes. I will indeed pull the valve covers to watch rocker movement. The real problem is I didn't build this motor, so I can only offer as much as I've been able to find. I've never had a problem with performance, or tuning, as I've always exceeded expectations from all my mopars, but this one has me stumped..... for now. Thanks for all the input so far.
 
If you had a cam go flat, you would have a noticeable top end tick in the engine.
I am betting on cam timing is off.
Also what did the pistons look like, how far down were they from the top of the deck.
Keep in mind parts store motors are built as cheap as possible and low compression to make them last thru the warranty period.
 
mderoy340 said:
With 170 crank compression I'll assume cam lobes and cam timing are good. Get the initial timing bumped up to at least 16, 18 and more if the motor responds. Do the normal initial timing set with max vacuum at idle followed by heat soak to check starter kickback.
Recurve dizzy then screw with a fuel curve.
What is your vacuum at idle?
Click to expand...

This is a very good point. OP mentioned total timing, WHAT is initial? If you have a smog (stock) distirbutor, it could be very little

EDIT OP said 13. It should be more, but it should not be a complete dog. Regardless.......try the above and get more initial timing into it to see if bottom / midrange is improved.

I'm BIG on piston stops and checking timing marks. This comes from years ago, finding a few that moved.
 
I like the idea of to totally find out where the mechanics of the engine are lined up at.

Did you/do you have a bridge to spans the cylinder to find TDC and check it against the balancer?

Not knowing the cam timing events or its exact maker, I would option for a different cam and start from scratch there. Then degree the cam in, set the distributor up again when you brake in the cam of course.

From there, I think you will have a better start point and understanding with and of your engine. Sometimes a dot to dot configuration is very off. Grinders fault/issue. It happens once in a while that the dot to dot can have the cam off 8*'s. Which would be huge.
 
The other dizzy I tried was a MP. I had the idle set at 16* initial timing with that dizzy. I'm leaning towards Rumblefish360 on something wrong with the cam in it. I did not remove the heads, so I was limited on what I was able to do with the pistons, as far as in the hole, or anything. However, with 170 compression, I'd say I'm good there. It seems to me the intake is extra warm, not the motor, just the intake. Weird. Also, if I do wide open throttle in Park, some gas (mist) comes up from the carb, but NEVER a backfire. Unless somebody comes up with a "catch 22" idea, it looks as if I'll have to pull the cam.
 
Sometimes, not exactly sure why, I have thoughts on it, but not now, a carb under a full throttle will have enough fuel going in at once it gets what I call ultra crowded and the fuel bounces back up.

This is the way I see it. Over the loud speaker, "That voice" comes over and announces the super sale of the century for THAT most wanted Christmas item that, that very crowd is waiting and shopping for. It is now 10 million people rushing to get that item! 1,000,000 lines into one isle, no waiting, everyone in NOW!

Some people are getting bounced out! That's what I think.
 
Does the throttle open the carb fully ?
 
rumblefish360 said:
Sometimes, not exactly sure why, I have thoughts on it, but not now, a carb under a full throttle will have enough fuel going in at once it gets what I call ultra crowded and the fuel bounces back up.

This is the way I see it. Over the loud speaker, "That voice" comes over and announces the super sale of the century for THAT most wanted Christmas item that, that very crowd is waiting and shopping for. It is now 10 million people rushing to get that item! 1,000,000 lines into one isle, no waiting, everyone in NOW!

Some people are getting bounced out! That's what I think.
Click to expand...

Like trying to pound packing peanuts into an icechest with a sledge hammer type thing? :D
 
All 170psi says is the valves an rings are sealing. It has nothing to do with how well anything else is working.
This was a mass-rebuilder engine? Does it have the exh valve rotators? Did you replace the springs as well?
 
moper said:
All 170psi says is the valves an rings are sealing. It has nothing to do with how well anything else is working.
This was a mass-rebuilder engine? Does it have the exh valve rotators? Did you replace the springs as well?
Click to expand...
170 psi says it has plenty of compression to run. For instance, 3 cylinders showing 50 psi would indicate a problem. The engine came with remanufactured heads, I'm sure, which included new valve springs. Not high performance valve springs, just new replacement springs is how parts store motors would most likely build it. I'm really doubtful valve springs are the issue here. Again, I've shared about all the info I have on the motor. I did not buy it new, it was from craigslist. I just took enough of it apart to verify it was new.
 
Was the transmission rebuilt? A band adjusted too tight could do this, major drag in the transmission = no power. When you drive it in second or third is it any different? Reverse?
 
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