[Syty] Overboost

[Dig]

The stock system, at its best, was barely able to control boost.
Further, it's very finicky to system changes - the chip calibration was done for a specific fueling cal, with a specific amount of backpressure.

Even in totally stock form, on a cool day at lower altitudes, you could get it to trip the overboost threshold.

Sounds like you've done the easiest fix, which is to take a turn or two out of the WG rod. Making sure that the rubber hoses and plastic lines are all intact after 15 years is another very good thing. Squeeze/Bend the elbows... if they tear, they needed replacing.

Another option - have someone burn you a stock chip that removes the overboost limiter. This comes with a bit of a risk- if the WG happens to sieze, and you're not watching it close, it's relatively easy to have them hit 28 psi +.  On street gas this is a quick motor death.

DataMaster is still available at www.ttspowersystems.com. Be advised that the program has many problems with newer laptops that don't have an on-board serial port.

Later,

Dig



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Message: 1
Date: Wed, 1 Aug 2007 08:08:21 -0400
From: "Lowell Raison" <lowell at raisongroup.com>
Subject: [Syty] Overboost
To: <syty at syty.org>
Message-ID: <000001c7d434$af142770$0401000a at hewlettmi4yof2>
Content-Type: text/plain; charset="us-ascii"

Did a tune up, including replacing the 02 sensor, and replaced the exhaust
on the 93 Ty we just bought. Runs great except that at WOT it starts to run
strong and then shuts down. It is showing a code 31 Overboost.

 

When the shop replaced the exhaust they eliminated the CAT. Is this causing
the overboost? 

 

If so, what is the best solution? Reinstall a CAT? 

 

Lowell

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