C4 LT1 in a C3, Gauge question.
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From: Sometimes I wonder... why is that frisbee getting bigger? Then it hits me.
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St. Jude Donor '06
C4 LT1 in a C3, Gauge question.
Hey all I am FINALLY getting the work started on the 77 that needs to be done and I know some of you have seen or done the Modern FI Lt1 from a C4 in a C3 conversion.. My question is which gauges can be used to monitor the engine. Do I need a Mechanical or Electrical Gauge to monitor the oil pressure, water temp, etc etc. The stock oil pressure gauge is currently working, and looks to be working very well. BUT I do not want to depend on a 25 year old gauge to monitor a "modern" engine. So I want to make the right choices when ordering my new aftermarket pieces.
Advice?? Comments? :cheers:
Advice?? Comments? :cheers:
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From: Chattanooga TN
Re: C4 LT1 in a C3, Gauge question. (Madmikeee)
I have a 90 TPI motor in my 69. I am using the old gauges with no problems. In 77 the oil pressure is electric, use the stock sending unit. Use an 82 temperature sensor (3/8 instead od 1/2" threads) and you will have no problems. I am also using an 82 Oil temp gauge in place of my clock. If you have them rebuilt (Clocks by Roger did a nice job with mine) I don't see why they won't do fine.
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From: Sometimes I wonder... why is that frisbee getting bigger? Then it hits me.
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St. Jude Donor '06
Re: C4 LT1 in a C3, Gauge question. (markdtn)
Sounds good!.. All I have to do is figure out exactly how he set this up. IE the temp sensor etc.
Anyone else have any suggestions?
Anyone else have any suggestions?
Le Mans Master
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From: Chattanooga TN
Re: C4 LT1 in a C3, Gauge question. (Madmikeee)
Your FI harness has a connector for the coolant temp sensor that the engine computer uses. You still need a regular sensor for the gauge. My wife had an LT1 Caprice and I think the sending unit is in the LH head between 1 and 3; same as the 77 350. Just use your stock engine harness, you still need it for oil pressure, temp gauge, alternator, starter, and power to the Coil. If you want to add oil temp, you probably have an extra now-unused wire going back through the bulkhead that you can use. I'm not super familiar with the 77 harness, but I'm sure there is something that you aren't using emissions related in the stock 77 engine harness. Use the stock 77 oil pressure sending unit. If you don't have a good 77 wiring diagram and a diagram for the LT1, now is a good time to get them. What are you doing for a fuel pump? Stock 82 sending unit with an LT1 pump? In my 69 I have an external pump and stock tank/pickup.
[Modified by markdtn, 2:33 PM 4/15/2004]
[Modified by markdtn, 2:33 PM 4/15/2004]
Thread Starter
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From: Sometimes I wonder... why is that frisbee getting bigger? Then it hits me.
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St. Jude Donor '06
Re: C4 LT1 in a C3, Gauge question. (Madmikeee)
anyone? anyone?? bueller? :lurk:
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St. Jude Donor '03-'05
Re: C4 LT1 in a C3, Gauge question. (Madmikeee)
Just jam a meat thermometer into a freeze plug and with a series of small dental mirrors, you should be all set.:D
I would just run factory senders with the original gauges.
I would just run factory senders with the original gauges.
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From: Sometimes I wonder... why is that frisbee getting bigger? Then it hits me.
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St. Jude Donor '06
Re: C4 LT1 in a C3, Gauge question. (Fastguy)
Just jam a meat thermometer into a freeze plug and with a series of small dental mirrors, you should be all set.:D
I would just run factory senders with the original gauges.
I would just run factory senders with the original gauges.
Sorry for the late response.. Had to rebuild my machine today.. the old HDD went Tango Uniform :banghead:
