Date: Wed, 16 May 2001 01:06:26 -0700
Reply-To: Chris Smith <chris.smith@aquila.net>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Chris Smith <chris.smith@aquila.net>
Subject: Re: New Engine, Poor Power, Low Gas Mileage - Update
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----- Original Message -----
From: Mike Finkbiner <mike_l_f@hotmail.com>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, May 15, 2001 10:03 PM
Subject: New Engine, Poor Power, Low Gas Mileage - Update
> I haven't put many more miles on my new Boston Bob engine, although now I
> can track it with the odometer working again, but I finally got into the
> shop to have the emissions tested.
>
> To re-cap, I have about 1200 miles on a new 2.1l engine with a longer
> duration cam and ported and polished heads. The gas mileage has been
about
> 15-16, power off the line is poor, and it surges rythmically at times.
>
> My digitool readings look normal. The one problem we have found is the
fuel
> pressure regulator is running about 4 psi high.
>
> I had a local shop run the vehicle emissions tests, assuming that if the
> fuel pressure regulator were the problem we would see it there. Here's
the
> results -
>
> RPM Idle 1800 2800
>
> HC 1398 299 140
> CO 1.51 0.94 0.66
> CO2 8.86 12.7 13.8
>
> According to the mechanic, that looks pretty good. He doesn't see any
need
> for adjustments to the AFM idle mixture screw. The one thing he thought
was
> high was the Idle HC, and a longer duration cam could explain it.
>
> Not sure what to do next. We will probably check the valve adjustments,
and
> have discussed replacing the Temp II just because it's cheap, but with the
> digitool readings looking good, I'm not sure. I sort of hate to just
throw
> parts at it. Do you suppose the pressure regulator could be a problem,
but
> it isn't showing up in high CO?
>
I have had the same problem on my air-cooled 2L for the 1st 3000 miles.
It's probably the rings. sometimes they just need more time to seat
themselves properly. Use it for a wide varitey of trips, some in town, some
around town and very little highway for a while. The different RPM ranges
will help seat the rings quicker. My 1st trip was a 1200 trip to BNWNTA.
It took another 1800 miles of shorter trips to get the engine power way up.
Be sure to change the oil frequently and to keep the breather clear. You'll
find a huge amount of blow-by for a while..
But then it may be something else..I have been wrong before.
Good Luck
Chris Smith
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