New engine issues

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dazedand confused

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hollister mo.
I recently had an 1985 318 short block rebuilt/modified at a really good machine shop. Bored 30 over, performance flat top pistons 9.5:1 compression. Erison cam: E 420121 Grind TQ20H 112+4 Love separation
Over lap 68 valve lift int/exh 0.449
Duration 292 rocker arm 1.50 and lunati performance flat taper hydrolic lifter.
The stock heads have been to the machine shop had valves done performance springs etc. New rocker arms: elgin and new rocker shafts melling. Edelbrock performer intake with 1" 4 hole spacer and 600 cfm edelbrock 4 barrel. Brand new mopar performance distributor with advanced curv. Also the ignition has been switched over to HEI. The cam is set correctly and the distributor TV on number one plug wire. I know it has a performance cam and will idle with some lope/ rough idle but the engine is not running tip top and when you go to give it gas it acts like it has the choke most of the way closed? It has a manual choke. I've checked the choke no issues and checked fuel pressure its good and no leaky ignition wires or vaccum leaks and made sure gap is correct between pickup/reluctor? The engine is in my 82 D-150
 
I unplugged distributor and left plugs out and turned key and rotated engine to pump up oil pressure. Used comp cam break in oil and mobile1 synthetic 10w40 WIC filter. Let engine run at 1800 rpm fluctuated off and on at 2000 rpm. For 20 minutes.
 
Checked all that it's good tried to adjust distributor while running but not a lot of difference when turning clock wise or counter clock wise. If you go a little to far it kills the engine? It has new plugs plug wires brand new mopar performance distributor /cap and rotor . It does have the performance curv built in? Might be too much advance? I did check for arcing none?
 
Checked all that it's good tried to adjust distributor while running but not a lot of difference when turning clock wise or counter clock wise. If you go a little to far it kills the engine? It has new plugs plug wires brand new mopar performance distributor /cap and rotor . It does have the performance curv built in? Might be too much advance? I did check for arcing none?

If it was only an advance issue the distributor rotation would have straightened it up.
Does it smell strong of gas when running?
Pop or backfire at all?
I agree to check those butterfly's for full travel.
 
K . It did say in the paper work that came from Mancini racing that the vaccum advance might have to be adjusted depending on the motor and how it's built. I'll also tear down the 4barrel to make sure nothing's clogging or stuck also
 
make sure fuel isn't dripping in from the carb as it's running at idle. That's bad...
 
It did have a miss with the old stock distributor but went away with new distributor and new gas mixed with 95 octane race fuel. No back fires or pops? Will inspect carb. Will check plug wires on distributor to see if their in the correct spots which they should be. Before I installed distributor I made sure piston #1 was at TDC on the correct stroke and positioned the distributor gear with ***** facing towards the right corner of the cylinder head like in the diagram and installed the rotor to the #1 position on distributor/ cap. When it idles it idles ok it's just when you go to give it gas it struggles. Thanks for your help . I've never adjuithe vaccum advance before either
 
I can't help the typos! Distributor was set on #1 position aka TDC= top dead center! They use AMS oil for the mopar engine shoot out in mopar muscle magazine AND oil is synthetic. The dot on the cam sprocket is in the 6:00 position and the dot on the crank shaft sprocket was in the 12:00 position. The engine was put together by a a really good machine shop guy who also used a degree wheel
 
Go to the basis. Easiest is vacuum gauge. That combo should be no less than 14 inches IMO.....

Second is a compression test...

JW
 
I can't help the typos!
Do NOT take this wrong, but you actually can help the typos. When asking for diagnostic help on this forum, we need to know as many facts as possible, and we need to know them accurately. Misspelled words and typos make it more difficult for us to help. When asking for help/opinions, it truly is best to be as accurate as possible, so I think it is a good idea to proof read your text before clicking the "post" button.
 
I think when I'm ready to post and send it my spell check on my touch screen phone changes the words at the last second? I usually try to spell correctly . Thanks for the constructive criticism
 
If as you say everything has checked out, then it has to be the combo.
The Wallace Calculator predicts 133psi cylinder pressure@722 ft elevation. I predict vacuum less than 10 inches at 800, if you can even get it down to 800.
I think yur gonna need a 3000plus TC and 3.91s atta minimum, just to get moving.

I agree about doing a compression test, and
don't forget to set the Transfer slot exposure to a little taller than wide, and set timing a lil on the high side. That cam likes extra idle-air and extra idle-timing. Make sure the PV is not dribbling.

On my 360, with a working PCV, I had to drill one hole in each throttle valve to get the Transfer slot set up, and she liked 18* to start with. I don't recall the hole size, maybe 1/16 to 5/64 each. Sneak up on it. If you go too big on the holes, then you will not be able to slow the idle speed down enough and still have about 14 to 16 idle timing with a manual trans and perhaps up to 4 more with a hi-stall.
The holes go in the primary valves on the T-slot side , about halfway between the edge and the shaft somewhere in the vicinity of the T-slots. As the holes get bigger you will be able to idle it down by taking timing out. Leave the transfer slot a little taller than wide.
If you have an automatic and the in-gear idle drops more than 150rpm from neutral-idle, then the neutral-idle is probably too high, take some more timing out. If the in-gear idle drops to less than 650 and she won't take throttle, and you are at less than 14* timing, your TC is probably too tight.

If you make the holes too big, don't panic. Just chamfer them well, and solder them shut. Then move over and start again. Yeah that happened to me in 1999. 100,000 miles later, and the solder is still in there.

After you get the idle sorted out, limit your power-timing to 34/36* all-in, but not including the Vcan.
 
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Aj I have no idea what you are talking about ? Transfer slots? I haven't been able to drive the truck yet just starting it up and letting it run. The truck has 727 auto with stock converter racing shift kit and the rear is 8-1/4 with sure grip and 3:55 gears. Why do I need a 3000 stall converter? The pistons are aftermarket flat tops and is a little above stock = higher then 8.5:1
 
Aj I have no idea what you are talking about ? Transfer slots? I haven't been able to drive the truck yet just starting it up and letting it run. The truck has 727 auto with stock converter racing shift kit and the rear is 8-1/4 with sure grip and 3:55 gears. Why do I need a 3000 stall converter? The pistons are aftermarket flat tops and is a little above stock = higher then 8.5:1
Well in post #1 you said 9.5 Compression ratio, now you say a little above stock. Stock was advertised as 8.0 and many members here say more like 7.8 .
when you go to give it gas it acts like it has the choke most of the way closed?
And here I assumed you were driving it. My mistake. But the end result is the same.
You said everything checks out, except the quoted part.
In my experience there are just three things that can cause what you are describing, which I'm assuming again; is a hard time taking throttle and a failure to rev up. And those things, again assuming you are correct in everything checks out OK, are: cam not properly synced to the crank, or intake valves not closing, or plugged exhaust.
The compression test will help with the diagnoses of the first two,and if very low, may lead to a Leakdown test which will prove one or all, of the three.
AS to the rest of my previous post, lets wait until the beast takes throttle.
 
And to add, random thoughts. You still have not nailed down for us the timing, either cam or ignition. A local friend here had a hot cam in a pickup and it was a dog. We ended up advancing it "I think" 6 degrees with a multi-key sprocket setup . In other words, installing a cam "dot to dot" IS NOT always where you want it for best performance

Additionally, you CAN NOT get decent performance out of an engine with a hotter cam while A....using a factory unmodified distributor, and B.....not knowing where the timing starts and ends. You need a SHORTER curve in the distributor than factory, and you need a LOT more initial advance

There "might be" a lot to do in order to wring this out, whether it's a bad choice of combo or not. I'm not familiar with that cam grind but it sounds like a lot of duration for a heavy vehicle.
 
once again...less then 10 seconds on google...and bingo

  • Duration @ .050:
    • 214/214
  • Duration Advertised:
    • 292/292
  • Grind Number:
    • TQ20H
  • Gross Lift:
    • .449/.449
  • Lobe Center:
    • 112
 
once again...less then 10 seconds on google...and bingo

  • Duration @ .050:
    • 214/214
  • Duration Advertised:
    • 292/292
  • Grind Number:
    • TQ20H
  • Gross Lift:
    • .449/.449
  • Lobe Center:
    • 112
that's the same thing I got when I Googled it and it sure doesn't seem like a real radical cam by any means.
 
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It is not.....had one in a old Class C motor home years ago....
 
How's the jetting in the carburetor? In Montana? What's your elevation? If it's a stock jetting in your at a high elevation you may need to put smaller Jets it's going to be way too rich.
 
Probably a 1406 Edelbrock. When I drove that old truck to my son's we had to rejet it in Colorado.
Fresh gas? Higher octane?
 
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Ok so i rechecked with my machine shop guy who built my short block. He said that he got a performance rebuilt kit for my engine that included 9.1 flat top pistons with no valve relief grooves bored the 318 30 over ! He degreed the cam with a degree wheel so all of that is taken care of and didn't need any off set crank pin or multi angled crank sprocket ? The engine has stock rods and crank. The edelbrock carb is a stock 600 cfm 4 barrel. All ports have been gasket matched on intake and manifolds so no obstructions it has High flow dual exhaust.Brand new mopar performance racing distributor with advanced curv . Heads : stock with light porting and valve job. Performance: valve springs ,lifters,push rods so no issues with valves opening and closing! The timing right now is only set up to start and let the engine idle . I don't know what else to say or ask?
 
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