Money and motor options, What is a realistic budget and parts list |
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Money and motor options, What is a realistic budget and parts list |
thelogo |
Mar 13 2017, 09:50 PM
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#1
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Senior Member Group: Retired Members Posts: 1,510 Joined: 6-April 10 Member No.: 11,572 Region Association: None |
1st off the engine im going for in no way needs to
Be optimised for performance (IMG:style_emoticons/default/screwy.gif) (IMG:style_emoticons/default/stirthepot.gif) What is the best combo for just cool reliable running In socal heat . Im trying to stay clear of d jet (IMG:style_emoticons/default/poke.gif) (IMG:style_emoticons/default/bootyshake.gif) So carbs or i like cb performance f.i kit but know little actually about it . What Crank Pistons Rods Cam Cyclinder s Fuel delivery Etc should i be putting together and what kinda budget windfall Should i be prepared for . I know its a sickness but cant be that expensive? I will use a machine shop to build the motor That have extensive experience with type 4 So i know thats gonna cost me major $ (IMG:style_emoticons/default/pray.gif) (IMG:style_emoticons/default/smoke.gif) Talk to me about proven engine combinatios (IMG:style_emoticons/default/beer3.gif) |
AZBanks |
Mar 14 2017, 11:50 PM
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#2
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Senior Member Group: Members Posts: 1,063 Joined: 7-December 05 From: New River, AZ Member No.: 5,245 Region Association: Southwest Region |
How does the D-jet and other 914 FI systems pick up the engine RPMS?
Is there a trigger/trigger wheel in the distributor or somewhere else on the engine? |
barefoot |
Mar 15 2017, 05:35 AM
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#3
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Senior Member Group: Members Posts: 1,282 Joined: 19-March 13 From: Charleston SC Member No.: 15,673 Region Association: South East States |
How does the D-jet and other 914 FI systems pick up the engine RPMS? Is there a trigger/trigger wheel in the distributor or somewhere else on the engine? The D-jet is a speed density based system. Once you know the rotating speed and manifold air density, in theory you know how much air the engine is inhaling. Consequently, you know how much fuel is needed. Speed is picked up thru trigger points in the dittsy and the manifold pressure and temperature sensors then get the density. Of course, there are some other tweaks involved like the cold start injector to provide an extra rich mixture for cold starting, and the throttle valve assembly has provision to fire the injectors more rapidly for acceleration. Some caveats however, this theory breaks down if exhaust gas recirculation is used as now you don't know the oxygen percentage in the incoming air and racing cams with large overlaps give mixed signals to the manifold pressure sensor. EGR was an issue for the use of the L-jet system, and all modern FI systems now use a rather simple heated wire probe to measure incoming air volume. |
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