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Author
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Topic: NEW motor setup/tuning help
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65ponycar
Gearhead Posts: 755
From: Dayton, OH
Registered: Jul 2003
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posted 03-03-2005 10:34 PM
   
Ok guys, I need some help on how to properly tune my rebuilt 302By rebuilt I mean: 1969 302 .060" over-bore
Work done:
- Cam bearings
- High volume oil pump
- Brass plugs
- Replacement crank
- Main bearings (.010)
- .060 pistons
- Rod bearings
- Rings
- Labor to bore/hone the 302 to .060
- Hot tank/install cam bearings
- Magnaflux block and crank
- Press pistons on rods
- cam, lifters, valve guides, everything else looked like new reused them
I'm also running:
- MSD ready to run distributor (both LIGHT springs, Plugs gapped at .40
- Holley Street Avenger 570 cfm, manual choke
- Offenhouser 360* Intake
- c4 automatic transmission
Breakin:
- 55 psi for oil pressure
- 195 degrees for temp
- 20 minute run at 2000 rpm
- no smoke, overheating, or other problems
*Note I included as much info as I could think of to help diagnose the problem(s), anything else I forgot ask... PROBLEM Engine has miss or vibration that occurs throughout entire RPM range... It will rev quickly, will not idle smoothly, and will not idle down very low (say lower than 1100 rpm will not produce a smooth idle) Any help? ------------------
'65 Coupe I6
5 Lug Front/8" rear(3.55) & V8 suspension conversion
TCP subframes
Mild built 302 to replace the six
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cougar395
Journeyman Posts: 25
From: elgin nd usa
Registered: May 2003
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posted 03-03-2005 10:46 PM
have you looked for a vacum leak yet?
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65ponycar
Gearhead Posts: 755
From: Dayton, OH
Registered: Jul 2003
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posted 03-03-2005 11:05 PM
I checked for a vacuum leak by plugging off:
1.) carb vaccum to distributor
2.) carb vaccum to pcv valve
3.) rear port of intake to c4 modulator
4.) sprayed carb cleaner around base of carb and intake/spacers/all mounting bolts/along all intake surfaces including edges...No change...  Forgot to mention also that the motor PINGS like a sob under load...
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65ponycar
Gearhead Posts: 755
From: Dayton, OH
Registered: Jul 2003
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posted 03-03-2005 11:06 PM
Actually I don't know if it is a PING or a KNOCK but you can hear some kind of knock/tap when you place the engine under load (i.e. accelerate, or climb a small hill)
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Moneymaker
Administrator Posts: 25883
From: Lyons, IL, USA
Registered: May 99
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posted 03-04-2005 12:00 AM
May sound elementary, but have you checked the firing order?
Did yo ever check if the cam a 289 or 351 firing order?------------------
Alex Denysenko
Co-Administrator and Moderator NHRA/IHRA/SRA member and licensed Superstock driver
NHRA and IHRA SS/LA & SS/MA National Record Holder '00,'01,'02,'03,'04 &'05
First SS/MA in the TENS!
IHRA division 5 Superstock Champion
Fleet of FoMoCo products including 88 ASC McLaren Mustang #28 The Barry of BarrysGrrl Quote #1: "I never met a magazine mechanic I liked."
Quote #2: "Make sure brain is in gear before engaging mouth!"
Quote #3: "If you can't run with the big dogs, stay on the porch!"
www.moneymakerracing.com
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indyphil
Gearhead Posts: 2398
From: Senoia, G.A. USA
Registered: Jul 2002
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posted 03-04-2005 08:18 AM
Does sound somewhat ignition related.
The knocking isnt good. Is it a detonation sound? Thats a little like someone left lots of ball bearings in your engine, or is it a tapping sound? It could just be timing - you didnt mention what timing you had it set to. But it sounds like one or more cylinders is misfiring. Could be that you have a loose plug wire or something silly like that - I even had a bad spark plug once. Pulling one plug wire off at a time will help to diagnose which cylinder is bad. Each time you pull of a plug wire the engine will slow down. if it slows down you had a good cylinder so put the wire back on. If you pull a wire and the tone of the engine doesnt change -thats the bad cylinder. If its a tapping sound it could be that something in the valvetrain is bad and causing the miss. At this point it might be a good idea to pull the valve covers and check everything over. If you have a bad cam lobe, loose valve, or someother bad/misadjusted component in the valvetrain - the one plug wire at a time trick will narrow it down to which cylinder has the problem. ------------------
'68 coupe, '66 289 C code
engine, edel 600cfm carb, performer intake, dual exhaust http://www.geocities.com/ottouk_77/68mustang.htm
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65ponycar
Gearhead Posts: 755
From: Dayton, OH
Registered: Jul 2003
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posted 03-04-2005 06:15 PM
quote:
Originally posted by Moneymaker:
May sound elementary, but have you checked the firing order?
Did yo ever check if the cam a 289 or 351 firing order?
Firing order is the 289, Counterclockwise 1-5-4-2-6-3-7-8 and yes I did get a chance during teardown to verify that I do have a 289 style cam. I now have triple checked my firing order, no problems there. quote:
Originally posted by indyphil:
Does sound somewhat ignition related.
The knocking isnt good. Is it a detonation sound? Thats a little like someone left lots of ball bearings in your engine, or is it a tapping sound?
It is more of a tapping/knocking sound, definetly does not sound anything like you describe of many ball bearings, more of a rythemic knock or tap that will increase with rpm, and only happens on acceleration... quote:
Originally posted by indyphil:
It could just be timing - you didnt mention what timing you had it set to.
I had the timing set at 12*, today I bumped it back down to 10* BTDC quote:
Originally posted by indyphil:
Could be that you have a loose plug wire or something silly like that - I even had a bad spark plug once.
I doublechecked on this again since you mentioned it, all connections were tight, with an audible click as each wire snapped on to the plugs/cap. I forgot to also mention, my plugs are ALL dry, and the small metal electrode is a light brown color, that is normal, correct? With the old engine they would be wet with gas and sooty... quote:
Originally posted by indyphil:
Pulling one plug wire off at a time will help to diagnose which cylinder is bad. Each time you pull of a plug wire the engine will slow down. if it slows down you had a good cylinder so put the wire back on. If you pull a wire and the tone of the engine doesnt change -thats the bad cylinder.
I never thought of doing this before  I tried it out. Pulled one wire at a time, each dropped the engine RPM noticeably, so does this rule out ignition?
Thanks for the help guys, I'll post back with any new info or if you think of something let me know!!
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65ponycar
Gearhead Posts: 755
From: Dayton, OH
Registered: Jul 2003
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posted 03-05-2005 08:41 PM
Today I put my vacuum gauge on it. From the rear port on the manifold, I have 15 Hg. The needle shutters between 14-16 Hg fairly rapidly.Does this help diagnose any further? thanks guys, I'm really looking forward to driving this, but need/want to have it correct first. Thanks
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65ponycar
Gearhead Posts: 755
From: Dayton, OH
Registered: Jul 2003
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posted 03-18-2005 04:28 PM
Still trouble shooting - I've been trying to minimize the amount of time I'm actually running the engine, just enough to warm it up (~180*) and do a test or try something out. Now my spark plugs read oily - like the rings are bad - could this (hopefully) be that the rings have just not seated yet? Will oiled up plugs create a miss? any suggestions?
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ntman
Journeyman Posts: 50
From: Mulkeytown, IL
Registered: Jul 2004
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posted 03-18-2005 05:28 PM
I would be less concerned about the miss and worry about the ping/knock. This may sound odd but if you don't have an engine stethescope you can use a 2' long piece if broom handle in a pinch to try to isolate where the noise is coming from. That is if it makes the noise while reving and not just under load. Rev the engine just until you can hear the knock and holding the stick to your ear touch the motor is various aress and when you get close to where the noise is coming from it will be louder and give a better idea of what might be causing it. *Stay clear of the fan Bart Just thought of this as well, have you checked your valve lash?? Too tight of a valve lash can cause a miss and too loose can obviously cause a steady knock that would increase with RPM...Just a thought [This message has been edited by ntman (edited 03-18-2005).]
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