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So I got some issues with my timing, and could use some help. I am running the rv1 cam, and was told by a guy (who I think is full of shit) and he said with the cam I have, I should be running my timing at 30 BTDC. Is that true, and how the hell could you even get it there? Dennis and I did mess with my timing, and got it to around 16, and it sure runs alot better, but I am lost with what it should be. I dont know anything about the lobe of the cam, or anything, so any help or ideas is appreciated!!!!

When I am lost on my sprint cars timing, I hold the fuel to about 3K rpm and advance it till it starts to sputter, then I retard it about 5 degrees and lock it down. I am not saying this is the best way to do it, but I have won main events doing it this way in a pinch.

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Certified pilots, looking down on people since 1903.

Thats about what I did to get it to where it is now. What do you think about what that guy said? 30BTDC???

If possible, get ahold of an adjustable timing light. This way you can set the mechanical advance timing to max out at 35-36 degrees when the motor is running at 3000 r.p.m. Once thats set, connect the vacuum advance hose to full manifold vacuum. With the baseline timing and an active vacuum advance working at idle, the timing should be around the 25 to 30 degrees BTDC.
The engine shouldn't ping at all because even with so much advance factored in, the engine isn't building full compression. If you stomp on it driving, the vacuum signal drops out and the timing retards as you acellerate. The mechanical advance still advances the timing as you speed up.

http://home.comcast.net/~chadwick.rober ... lained.pdf

Give this a read... It can help you out.

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Previous setup: 4.1 Buick V-6/TH 350
Current setup: 400 Small Block Chevy V-8/TH 350
9" ford rear end/short bed/blue
What do Water, Electricity and Humans have in common... They all travel the path of least resistance.

Thanks for the info. 1 question-- How can you tell when you are at that high of a degree when my timing mark plate thingy only goes to I think 8 BTDC???

That's why you need an adjustable timing light. These specific timing lights have an adjustment to factor in advance. Set the light at 10 degrees, set the distributor so the timing mark lands at 0 and it's at 10 degrees. Set the light at 36, put the timing mark at 0 and it's running at 36 degrees.
Or you can make marks on the harmonic balancer or use timing tape. The tape has timing marks on it and you wrap it around the balancer. It's tough to install because you dont have much room and it has a tendency to fling off at speed.
Making a mark on the balancer is the smoothest way but you'll need to figure out the distance from the 0 TDC. Different diameter balancers require different measurements.
Once you have a 36 degree mark, set the timing with the motor running at full mechanical advance and no vacuum advance with the 36 degree mark you made is lined up to the 0 mark on the timing tab.
After you have the timing set, connect to a manifold vacuum source and then adjust your idle and mixture settings.

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Previous setup: 4.1 Buick V-6/TH 350
Current setup: 400 Small Block Chevy V-8/TH 350
9" ford rear end/short bed/blue
What do Water, Electricity and Humans have in common... They all travel the path of least resistance.

Thanks!!!!!!!!!!, I will try to track down a light.

Good info guys.

The only thing that hasn't been mentioned is the timing advance curve of the distributor. I've seen stock HEI distributors keep advancing all the way past 4000 RPM. This may be a benefit for emissions, but it's not the best for performance.

As with all tuning, this will vary from motor to motor, but a common setup with HiPerf engines is to set the spring rate and advance stop bushing so that the advance is all in by 3000RPM.

Tuning your timing and carb is worth every bit of effort you can put into it. I have seen a night and day difference in engines before and after tuning.

There's something to concider when using full manifold vacuum with a fat cam. The bigger the cam, the less manifold vacuum you'll create. If the vacuum pull isn't strong enough to fully draw the vacuum advance, your idle will float around and not stay consistant. To remedy this situation, a new vacuum advance canister will be needed. You can swap out a canister without removing the distributor. But figuring out which canister to use for any specific application can be confusing. So your best bet is to go with an adjustable canister. A vacuum gage will help you figure out the best setting.

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Previous setup: 4.1 Buick V-6/TH 350
Current setup: 400 Small Block Chevy V-8/TH 350
9" ford rear end/short bed/blue
What do Water, Electricity and Humans have in common... They all travel the path of least resistance.

Very good info... I bookmarked this one..

Thanks to you all!!!!!! I think my buddy Frank, is gonna bring an adjustable timing light tonite to work, and hopefully we can get this thing running better. Granted, it already is running a ton better just timing it like Dennis and I did, but I wanna get it dialed in a little better!!!!!!

So, we just timed it, and put it to 30 BTDC, and it seems to be very happy I had my dist. hooked to the wrong vac. on the carb, so after putting that where it needed to be, and doing the timing, it seems to be very happy So, now I guess we'll just wait and see how it runs for the next few days, and hopefully next week, I can go to the track, and get a better run than i have been!!!!!!!!!! THANKS you guys for all the help

glad you got it sorted out .... give us a time difference on the run if you can from old to new

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My old but now gone Luv...

18 in Redding---15 in Medford----next week?????

we wont count redding it looked like you where going bass akwords

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My old but now gone Luv...

OWEEEEEEEEEEEE!!!!!

When are you guys going to come back to redding? I finally got most of my stuff settled in the new house and just started working on my truck once again. Other than a leaky trans cooler line its ready to go.

Hey Gabe, was that your truck for sale in the Redding paper?????? I HOPE NOT

I posted my truck on craigslist for a while never got a serious inquiry on it. I came to my senses and started working on it again. My girlfriend wasnt really all that happy that the truck hatched a litter of black widows out in the garage (thought I had that problem taken care of) So now that I have that taken care of Im back at it again.

good to hear you are back at it