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tornik550 |
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#1
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Senior Member ![]() ![]() ![]() Group: Members Posts: 1,248 Joined: 29-January 07 From: Ohio Member No.: 7,486 Region Association: None ![]() |
I am in the process of tuning my car after a rebuild. I have dual weber 40's. My engine is a 2.27L. Everything is going pretty well. I am slowly getting the jetting closer and closer. I was driving around at about 60mph yesterday. The head were hotter than I like (325 degrees). I checked the spark plugs and they were bone white. The main jets were at 160. I increased them to 170 (above 160 I only have increments of 10). With the increase to 170, the car is running very well and the temp at around 60mph cruising is around 275. I sped home, tuned off the car and took out the plugs- bone white. I was quite surprised.
The main jet size sounds high too me. Does it sound high to everyone else? Is it possible that I am needing a high main jet size because of the float level? I have my floats set at 10.5 with the gasket. Any opinions would be greatly appreciated |
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john rogers |
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#2
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Senior Member ![]() ![]() ![]() Group: Members Posts: 1,525 Joined: 4-March 03 From: Chula Vista CA Member No.: 391 ![]() |
The venturi's sound a bit too small as you surmise the 34's would probably be better. I used to use the website here: http://members.rennlist.com/webercarbs/
to do the venturi calculations. Several other things I would check, what is fuel pressure when running, not idle and it should be 3.5 to 4#. What fuel pump are you running? I hope it is NOT one of those little Facet pumps as they tend to not have enough capacity for a hot rodded engine and the hard pulses they produce can cause needle/seat problems on Webers. Do you have an O2 sensor in the exhaust? If not I would suggest one to help save the engine from overcooking itsself. Finally, I would set the float levels on the high side especially since you have a lot of time and $$$$$ in this and it is better if the engine is too rich as opposed to too lean! Good luck |
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