Rule question

[Mobigsly]

So can we run say a 205/60R15 with a 215/65R15 or do we have to stay in the same series ie..60?
I read the rules as if we can mix match size and series.
T.J.

[DB Motorsports]

thats a good question, i would like to know myself.

[pappywrench]

Good point, In my chat with Billy he stated different sizes within series(205-60-15, 215-60-15, 235-60-15), but it is not stated that way in the rules, a clarafication will most likely be posted. Thanks for pointing it out.

[Mobigsly]

so you have to stay within the series. correct?

[pappywrench]

I'm sure billy will clarify it when he sees this post.

[NEETS-1]

You Can Mix Match Any Size Tire As Long As It Meets all Other Rules....ie; 215-70-15/235-60-15

[lefty turner]

How about mixing wheel sizes (14"-15")?

[Bobby Pease]

BILLY...

were people complaining about the NO stagger rule? is this the reason for the change?
thanks...Bobby

[NEETS-1]

Not altogether...ease in tech is another reason. Plus not all people can get 4 used tires all the same exact size all the time and cheaply. Another reason is spares.
Some will use the rule to their advantage for stagger, others will use it just because that's all they have.
Wheel sizes will all have to be the same...ex; all 15"

[EnduroFromDE]

Hey Billy, (Or to anyone else who knows)
How do you go about checking the Vacuum on the car?
Not being a machanic, how would I check it myself??

[NEETS-1]

If you have a bonestock car...don't even worry about it. You'll probably come up with 20" or more. I am more worried about curbing the hot rods.
But if you want to check it, you will need a tachometer and a vacuum gauge. Hook up the hose from the vacuum gauge to a vacuum line, either at the base of the carb, or the rear of the intake. Hook up your tachometer. Have someone step on the gas until you have a steady 1000 RPMs. Read the gauge and that will be your vacuum. It will read in "inches".

[richardpetey]

If your vacuum guage reads about 11 or 12 "inches of mercury" at about 1200 rpm, it means you have a nice healthy engine, hehe..................
The absence of less than one atmosphere doesn't make you a bad person(at least not on my planet)................
Two years ago I couldn't spell machanik, now I are one......................
UNCLE PETEY.....................

[Rich Johnson]

Craig mentioned to me..."It would help if we had a marked port to hook the gauge up to" This would speed up the process so our tech guys could "move along the line" and get their job done...What do you think Pap?

RacinRich

[vsmidge68]

Question....I have a 1986 monte carlo with a stock 305. The engine has 130,000 miles on it. I tested the vac. off the base of the carb. and with a NEW guage (and an old guage) @1000rpm I got 15". Im not trying to raise a conflict, but I want to make sure Im legal. I know for a fact that carbon buildup on valves, weak valve springs, timing, worn camshaft, do play a factor in low vac. ??? . Like I said, I just want to be legal.


Thank you.

[NEETS-1]

I have never ever seen a stock chevy v8 as low as 15" with no work done or with even 300,000 miles on it. You must have a vacuum leak or you are not testing at the right place. Try unhooking your brake booster hose and test it there. Make sure all other vacuum hoses are attached and or plugged up. Also check all your vacuum lines for cracks/leaks.
And, yes, you are right that older stock engines with wear from lots of miles and carbon build up will have a lower vacuum, but down to 19/20 from a healthy stock motor that pulls about 22/23" of vacuum. That is why I set forth a minimum of 17" of vacuum, giving way to older engines and at the same time curbing hot rodded motors.