tuning tips for going on trip...

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R

redfastback

Don't ask me... my garage is empty
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i am going to reno in the cuda this weekend and wondered if i should change anything like timing, jetting, etc. since reno is at 4500 feet and donner summit reaches 7000 feet.

will it run too rich? will it drive like crap?

i have never driven that high of elevation in a carbureted vehicle.
 
nobody?? bueller..........bueller.................bueller...............
 
What kind of carb are you running? Generally, I'd drop jet sizes on a holley 2 to 4 sizes and bump up my timing by two degrees. Problem is, it'll run like crap till you get to 3500+ feet.

When I drive drive down from Denver (5280'), I bring jets up to 4 sizes larger and my Mallory box has a manual switch that takes out 4 degrees of timing. I hope this helps.
 
You might be OK with 72's. Here in Denver I'm running 74/80 on a 650 DP on 10.2:1 360 with a 216 @ .050 lift cam, headers and LD4B intake and I think It's still a little lean.

Just bring a pair of 68s and 70s with you as well as the appropriate tools with you and a couple bowl gaskets just in case. I would'nt worry about the secondaries unless your going racing while your there.

Don't be suprised by the loss of power at altitude. 2% loss for every 1000' is the rule of thumb but some say more. There's really no way to make up for it short of super/turbo/charging or increasing compression ratio. Just keep an eye on the exhaust and look for the tell tale black smoke.
 
ramcharger said:
You might be OK with 72's. Here in Denver I'm running 74/80 on a 650 DP on 10.2:1 360 with a 216 @ .050 lift cam, headers and LD4B intake and I think It's still a little lean.

Just bring a pair of 68s and 70s with you as well as the appropriate tools with you and a couple bowl gaskets just in case. I would'nt worry about the secondaries unless your going racing while your there.

Don't be suprised by the loss of power at altitude. 2% loss for every 1000' is the rule of thumb but some say more. There's really no way to make up for it short of super/turbo/charging or increasing compression ratio. Just keep an eye on the exhaust and look for the tell tale black smoke.
Click to expand...

well. she didnt spit out black smoke. i did lean her up on the idle mix. ran better around town. but the funny thing is that she used a quart of oil each way! why? no smoke out the back, no leaks. is it going past rings since i have 2 breathers and no pcv? this seems to be a mystery.

any thoughts?
 
haven't even thought much into it. she never used oil before. tooooo tired/cranky from driving all weekend being sick and not sleeping.

can't see it, but i knew a certain poster would show up.
 
That's a mystery to me too, Red. Sorry I can't be of more help in regards to this very odd "event". Do you think it's due to the altitude, or just because it's a long trip?
 
got a 340 shortblock and new sb 727 for sale cheap on the parts for sale list if your interested red,no I dont think its funny at all.
 
redfastback said:
haven't even thought much into it. she never used oil before. tooooo tired/cranky from driving all weekend being sick and not sleeping.

can't see it, but i knew a certain poster would show up.
Click to expand...

Same issue here. I drive mine on the hwy at 65-70 mph most of the time to shows 200 miles away. It will use a quart of oil every 600-700 miles and it still runs good. Might have found a slight crack in my intake gasket, so I am replacing it. It turns 3,000 rpm at those speeds and I do go up and down grades with it. It has a lopey cam and lower compression pistons. I think these motors use more oil than what we sometimes notice, depending on use.

What oil are you using? how is your compression? Mine checked out within 10-15% of each other, so no ring issues. How do the plugs work. Lol, you probably already know all of these things, but I am just spouting out ideas.

-Justin
 
I just wait for the oil light then add 3 quarts... :toothy10:

My ex used to do that to her car.
 
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