500 crate wedge timing

[jddodge]

Hi,
My 68 charger has a 500 crate wedge in it.
Bought it like it is. But feels like the timing is a but of. When in high rpm it stalls a bit, eyes are burning when you standing behind it. Has a rebuild 850 holley double pumper.
I want to begin with the timing and set that right..
Anyone know what basic timing this engine needs? Dont know about which camshaft it has.. only know it has low vacuum
Also vacuum line from ignition to carb is plugged.

Thanks,
J.D.

 

[BLK 68 R/T]

Get a vacuum gauge and set the timing for the highest vacuum reading. Initial I would start at about 18-20 degrees advanced and fine tune from there on timing. Carb may need some tuning as well.

 

[4mulas]

You may have a fuel issue crating both the burn and the bog. Set the timing at 16-18 maybe but figure out the carb first. Then time it.

 

[hunt2elk]

An air/fuel gauge is a great help whrn it comes time to play with your carb.

 

[jddodge]

Thanks guys
Gonna buy some gauges!!

 

[Kern Dog]

First off, burning eyes is typical of an OVER rich condition where the engine is getting more fuel than it needs. That would make sense since a double pumper carburetor is usually not the proper choice for a street car.
For drag racing, they are great because they flow a LOT of fuel. On the street, you spend most of the time at idle or part throttle. Double pumper carburetors are best for wide open throttle action.
Low vacuum...Okay, in many cases on engines with a rough idle and a big cam, you need more initial ignition timing than a stock engine. Big camshafts are not as efficient at idle compared to a stock, mild cam so the timing needs to come in sooner to compensate. Where a stock engine may be fine with 5-8 degrees before TDC, your engine will certainly want and need more than 15 degrees. I have my 440 based 493 set to 19 degrees initial with a total of 34 degrees. My camshaft is not really wild but it it isn't stock either.
It may be difficult to get the initial to where you need it without the total going way too high. If that is the case, come on back and we will steer you to how to modify your distributor to get where you need to be.
My car is tuned using a wideband Air-Fuel meter that I have in the car mounted to the dash.

This was taken a few years ago...

I had a Gear Vendors overdrive and an automatic trans then!
The gauge you want is the one on the right...AEM is the manufacturer.

Where is Reusel? Is that in the Netherlands?

 

[jddodge]

First off, burning eyes is typical of an OVER rich condition where the engine is getting more fuel than it needs. That would make sense since a double pumper carburetor is usually not the proper choice for a street car.
For drag racing, they are great because they flow a LOT of fuel. On the street, you spend most of the time at idle or part throttle. Double pumper carburetors are best for wide open throttle action.
Low vacuum...Okay, in many cases on engines with a rough idle and a big cam, you need more initial ignition timing than a stock engine. Big camshafts are not as efficient at idle compared to a stock, mild cam so the timing needs to come in sooner to compensate. Where a stock engine may be fine with 5-8 degrees before TDC, your engine will certainly want and need more than 15 degrees. I have my 440 based 493 set to 19 degrees initial with a total of 34 degrees. My camshaft is not really wild but it it isn't stock either.
It may be difficult to get the initial to where you need it without the total going way too high. If that is the case, come on back and we will steer you to how to modify your distributor to get where you need to be.
My car is tuned using a wideband Air-Fuel meter that I have in the car mounted to the dash.

This was taken a few years ago...

View attachment 1155344

I had a Gear Vendors overdrive and an automatic trans then!
The gauge you want is the one on the right...AEM is the manufacturer.

Where is Reusel? Is that in the Netherlands?

Yes its in the Netherlands, you got that right!

And indeed im mostly cruising it around a bit.
Last time my girlfriend was driving behind me in her peugot lol and told me she could smell the fuell pretty good..

 

[rikkitik]

Definitely get yourself some guages.
As stated above, when you go to tune it, bring the timing up, and watch for best/highest vacuum. There's really no "set" timing point, the engine might like anywhere from 15 - 22 degrees initial advance. When you find the inital advance the engine likes, you may (hopefully) need to bring down the idle speed. Try to adjust it to 900 - 1000 rpm. Or a bit lower if you can keep it above about 11 inches of vacuum.
Once you have some advance in it, turn the idle mixture screws, clockwise, to lean it out. Watch the manifold vacuum, if the engine responds to the mixture screws, that's a good sign.
If you can't lean it out enough to affect the idle, then it would be a sign that the carb needs to come off.
If it does respond to the mixture screws, you can then reduce the idle speed to whatever you're comfortable with.
Also, if it does want that much initial advance, you will then need to check your total advance. Depending on the distributor, you may be able to limit it's mechanical advance, you usually want end up in the range of 34-36 degreed total. That could be reduced by available fuel quality.
The above, and how the engine responds to it, should hopefully narrow down some of the tuning questions.