Hummm..
Maybe there is some way to do it by putting a dial gauge plunger through the
spark plug hole..
In fact, if you dont have a dial gauge, you can probably rig something up a
wooden dowel, screw in type fitting and some clear tubing (I'm going to have
to
try this)
In any case, you just need some kind of scale so that you can mark where the
piston reaches it's highest point. then what you do is roll the engine back,
and
find a point that is about 10 thousands below it highest point (value doesn't
really matter, but must be consistant), and then crank the engine forward until
the piston drops again to the same point on the other side. During this
process,
you must have a calibrated 'timing disk' on the end of the crank, and you need
to mark both of these positions. TDC will then be exactly between your two
marks.
You then need to do the same thing on the push rod for the intake valve on #1,
taking the two mesurements, and then finding the mid-point.
If you do need to install an offset key (and chances are you will), I found
that
this is virtually impossible to do with the engine bolted in place (I learned
the hard way), since you cant get the timing cover ,and crank pully off because
of the frame cross member. I had to undo all the engine and tranny mounts, and
raise the engine up about 4 inches, and even then it was a pain.
BTW - If you need it, I can make a copy of the instructions I have and send
them
to you, but your timing specs may be slightly diferent for your cam.
- Bryan
>X-Originating-IP: [203.101.49.195]
>To: spridgets@autox.team.net
>Subject: Re: fine tuning
>Mime-Version: 1.0
>
>I have 'How to modify your mini' (Vizard) but unfortunately it dosen't
>explain how to time the cam...just says how important it is!
>Is there anyway I can check to see if it is way off the mark without pulling
>the head?.....really don't want to do that for a while if I can avoid it.
>Andy
>
>>From: Bryan Vandiver <Bryan.Vandiver@eng.sun.com>
>>Reply-To: Bryan Vandiver <Bryan.Vandiver@eng.sun.com>
>>To: Bryan.Vandiver@eng.sun.com, trunkie@hotmail.com
>>CC: spridgets@autox.team.net
>>Subject: Re: fine tuning
>>Date: Thu, 16 Sep 1999 10:27:05 -0700 (PDT)
>>
>>The problem with installing a new performance cam, is that during the
>>machining process, they
>>sometime get a little offset, from true 0. The other problem is that timing
>>marks on or engines
>>were never that precise to begin with. The cam you got should have come
>>with some specifications on
>>where it needed to set. The Kent Cam kit I got came with some very specific
>>instructions, I belived
>>my cam was supposed to be set to 6 degrees before true TDC of the #1
>>piston, and when using the
>>factory marking on the timing gears, it was actually between 12-14. To find
>>true TDC, with the head
>>off, I used a dial indicator, and rocked the engine forward and back to
>>find TDC for piston #1. I
>>had a timing disk mounted to my crank pully(came with my cam), and zero'd
>>it to TDC, I then check
>>valve lift on the the #1 intake valve, with the dial indicator to find out
>>how much out of sync the
>>cam was from the crank. To sync the cam with the crank, I got a cam gear
>>offset key from MiniMania
>>(they are local to me). The offset key, will change the timing 2X the
>>offset of the key itself, so
>>a 3-degree offset key changes timing by 6-degrees. In any case this was a
>>fairly time consuming
>>process, and took a little trial an error. but once it's done, you don't
>>have to do it again unless
>>you change cams. In any case, I'd recommend you get a copy of David Vizards
>>book (Tuning BL's
>>A-series engine), It has very through instructions on how do do all this,
>>not to mention details on
>>every possible performance modification that can be done to our engines,
>>and evaluations of most
>>products on the market.
>>
>>Regards,
>>Bryan Vandiver (59-bugeye)
>>San Jose, CA
>> >X-Originating-IP: [203.101.49.220]
>> >To: Bryan.Vandiver@eng.sun.com
>> >Cc: spridgets@autox.team.net
>> >Subject: Re: fine tuning
>> >Mime-Version: 1.0
>> >
>> >
>> >
>> >If you have not 'timed
>> >>the cam to true TDC, you are not taking full advantage of the
>>capability,
>> >>and even being off 2-3
>> >>degrees on the a-series, can result in a lot of lost potential,
>>according
>> >>to Vizzards book.
>> >
>> >I couldnt quite get my head around the 'cam timing' thing.
>> >So it's not just a case of lining up the dots on the timing gears?
>> >I mean, to me there seems to be only a couple of ways to fit it, the
>>right
>> >way or lots of very wrong ways.
>> >
>> >______________________________________________________
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>
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