Engine rebuild woes Options

[emerygt350]

Yeah, first, double check the plug wire order, then double check the timing, then check the coil. I like that weak spark idea and hot coil. Coils work great until they just don't all of a sudden.

[emerygt350]

Yeah, first, double check the plug wire order, then double check the timing, then check the coil. I like that weak spark idea and hot coil. Coils work great until they just don't all of a sudden.

Come to think of it, double check that the plug wires are actually firmly on the spark plugs and in the cap (same for the coil wire). I have had them loose and ended up with random backfiring etc (thank god not on my 123, I hear that will destroy a 123).

[targa72e]

you need to start at square one. With a compression and displacement increase nothing as it was run before will be correct. Start with basics. Are there any vacuum leaks. Are plug wires on correct. Is point gap and dwell correct. Is the timing at idle and full ignition advance correct for your 10.2 to 1 motor (original was around 8 to 1) Are valve clearances correct. Then move on to is carburetors. Are the linkage synchronized and correct. Then tune with wide band O2 to see if idle, part throttle and full throttle jets, venturi etc are correct. Lots of stuff to fiddle with and since non stock you cant just use stock settings.

john

[falcor75]

Is 32 venturis big enough for a 2,3 with high compression?

[Shivers]

I put CB performance kits in my 40's. The ventures are 34's and they are on a
warmed up 2 L.

[falcor75]

I just got hung up on that it idles fine but doesnt work when driving. I agree with many others. Get yourself a notepad and start checking everything and make carefull notes of what you have checked and what you have measured. No sense in spending money on guesses.

Compression, are all cylinders equal within reason
Leakdown, any oddities?
Fuel pressure, within spec?
Timing,
Distributor and ignition leads installed and hooked up correctly
How does the spark plugs look, are they wet or sooty etc, make notes
Air leaks, both topside and bottom (exhaust side)
Carbs and linkage, sync between banks, measure drawn air with a synchrometer
Carb jets etc

There is no magic ticket, its just systematic fault elimination and keeping notes.

[rfinegan]

Pull a Jet stack and Idle jet and let us know what you are running. Are these Weber 44idf or 40 idf? You already mentioned the Venturis size was Reduced to 32?
Once you get the basics baselined you may want to borrow a wide band O2 to see what is going on wit the carbs. Popping sounds like you are lean
What do the plugs look like? You can set them up without The O2 but just takes a little trial and error

[Superhawk996]

There is no magic ticket, its just systematic fault elimination and keeping notes.

(IMG:style_emoticons/default/agree.gif)

Lots of guessing always happens on posts like these. I need to figure out a way to start some sort of over/under betting pool when these posts pop up. How many guess until the solution for the root cause is properly identified?

Placing call to Vegas casinos now to get in on the action . . . . (IMG:style_emoticons/default/laugh.gif)

I've always kept a journal style notebook for each of my cars. Maintenance info, engine & suspension tuning info, and troubleshooting info. You'd be amazed how handy it becomes to have that history years later when it's all but long forgotten.

[rhodyguy]

That's a Mallory Unilite for the dist. Usually, dimpling the tin around the dist is required to fully seat It. They can be picky about the SP wires. What is your idle RPM? Shoot for 950. Just use one idle speed screw to raise the idle. The rest of the linkage will follow suit. For the displacement I think your Venturi are too small. My 44s have 32mm Venturi installed for a 2056. Lastly, what type of fuel pump are you using? Lots of variables to sort thru.

[VaccaRabite]

Your mechanic set the idle and maybe never drove the car. I'm sure it's fine under no load.

I very much doubt that this is a mechanical problem. That said.
1) did the builder do a cam break in?
2) did the builder do a ring break in? (this may be something that you are expected to do.)
Now its your turn:
1) check the basics. Do valves. Do compression.
2) you need to note your carbs. Find out the size of your: Mains, Idle, Vents at least.
3) get a balancing snail and check balance between carbs at hot idle and at 3K rpm.
4) Do all the stuff mentioned in the previous posts about checking timing.


PS: my Vegas bet is that the builder set the timing and balance with the engine and carbs ice cold. Like overnight, below freezing cold. Its been a cold winter in the MidA. As soon as they warm up it all goes to shit and you have an unhappy engine. Once set while warm, the engine starts behaving much nicer.

Zach

[william1764]

Your mechanic set the idle and maybe never drove the car. I'm sure it's fine under no load.

I very much doubt that this is a mechanical problem. That said.
1) did the builder do a cam break in?
2) did the builder do a ring break in? (this may be something that you are expected to do.)
Now its your turn:
1) check the basics. Do valves. Do compression.
2) you need to note your carbs. Find out the size of your: Mains, Idle, Vents at least.
3) get a balancing snail and check balance between carbs at hot idle and at 3K rpm.
4) Do all the stuff mentioned in the previous posts about checking timing.


PS: my Vegas bet is that the builder set the timing and balance with the engine and carbs ice cold. Like overnight, below freezing cold. Its been a cold winter in the MidA. As soon as they warm up it all goes to shit and you have an unhappy engine. Once set while warm, the engine starts behaving much nicer.

Zach

Hi Zach - What shop would you recommend? Maryland...possibly PA? You know my limitations;-)

[nditiz1]

Bring it on up to Mount Airy, we can take a look.

[VaccaRabite]

Hi Zach - What shop would you recommend? Maryland...possibly PA? You know my limitations;-)

This is the worst time for a shop. Everyone good will be slammed with spring in the air.

I'd go back to the shop you got the car from. They need to have the chance to make it right. When it comes down to it its probably something relatively easy, and they should put you at the front of the line when they do so.

Zach

[VaccaRabite]

Bring it on up to Mount Airy, we can take a look.

Or do this. Nick has the know-how.

Zach

[william1764]

Bring it on up to Mount Airy, we can take a look.

Or do this. Nick has the know-how.

Zach

Thanks Zach

[william1764]

Bring it on up to Mount Airy, we can take a look.

Sent you PM Nick

[cgnj]

Hi,

If that is a unilite, the tin needs to be massaged so that it seats properly. On my build, I had to reindex the distributor gear (I have a vacuum can on mine). Other things to think about.

It is quite likely it is used. There also were QA issues with later Unilites.

1.TDC on #1
2. Pull distributer. Check for grey/grey springs.
3. Compare the drive gear to this pic. Look good. reinstall distributor and rotor. Rotor points to #1. If it's 180 out the gear is installed incorrectly. Use a magnet to remove the spring and reinstall the gear correctly.

Time it and go. If you're not getting 22 degrees total advance, I can lend you the adjustment keys.

I looked closely at your picture. The gear is not indexed correctly. 180 out. You need to confirm that you have spiral wound plug wires. You will cook the optical rotor. Good luck,

Carlos

[rhodyguy]

Or, install the plug wires starting on true #1 in the correct order if you're in a hurry. I mark the Firing order on the cap terminals with a Sharpie.