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Gordo

Change from triple webers to fuel injection

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If your car is primarily a road car the carbs are too big. The air flow through 45mm carbs when fitted to an engine with cylinders of less than 530cc's is too slow the result of which is poor atomisation of the fuel. Wet fuel won't burn (only the vapour burns) resulting in a rich mixture, poor throttle response and lack of power. The correct size for a L240/60/80 engine is 40mm with 32mm chokes. 

 

Fuel injection systems can tolerate much larger throttle sizes due to the fact that the fuel is delivered via the injectors as fine mist which vaporizes almost instantly. This also explains the reason for improved fuel economy when compared with carburetors.

 

Cheers

 

Gordon Dobie

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Hi Gordon, the car is mainly used on the race track, what you have said makes sence, some times the plugs are so wet it will not fire. ( just like flooding ) . But changing the lengh of the secondarys seems to of helped, I will find out on Sat with Dyno tune. Cheers.

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Where and when are you getting it tuned Gordo?

Wife is away and I have the kids, but might be able to find some time to pop by if it's local.

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Hi Guys, the dyno didn't happen, even though I spoke to him on Tuesday and confirmed sat 8.30am he double booked me. forgot all about it. Said he could do something about lunch time and would call , but you guessed it ,he didn't call. I rang twice but he did not answer. So it's all up in the air at the moment. f #%&*!. Not happy.

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Hay Gordo book it with pete ;) and them I cam come across the road and watch peter do his magic it only a short trip down the road . ;)

Bruce 

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Hey Bruce, the thought did cross my mind, I will wait and see if I can get on the dyno this week. After the v8supercars I was all fired up and took the zed for a thrash, and I must say the old girl felt strong. Pulled strong all the way to 7 grand. But the exaust note is bloody loud. Cheers.

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Dyno Today. We ran it up first and was 5kw from my best, alittle lean since the shorter secondarys. The power curve was or some from 3000rpm to 7000rpm. That exhaust change took the dip out of the power curve and is now good. A littel rich 3000 to 4000 then a littel lean 4500 to 6000 then Little rich 6000 + . Smoothed it out a bit and was OK. Timing was set at 14 deg. Then we went for the cam timing. A advance 2 deg and nothing happend, so we retarded it but there was no more adjustment, So what do you do, rotate the cam one tooth. but it retarted to much,so we went to put it back and could not get the cam wheel onto the cam, chain to tight. the timber wedge must of come loose and the tentioner had taken up the slack, tried to get it back in but after an hour had to concede defeat Sh#*%t.  It was al lgood and we had to chase just that littel bit more. I guess you never no until you give it a go. So I brought it home and will fix this week , and run it on the dyno next sat for check. Racing at msca sandown this Sunday, wish me luck. The only problem I have is how do you get the engine to top dead with out the chain on to turn the cam. Will the pistons hit valves. Cheers.

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good to hear the exh side of things is better not so good for the cam give me a call i will tell you how to do the job with out hitting the valves, not to hard don't fear 8)

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Thanks Pete, will call you tommorow arfo. The exahast note is really loud now, might have to get a new magnaflow muffler, running out of time , seven days to Sandown.

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No problems mate.

Did you try the reducer as this will change the noise but the certainly are noise with the 3", it took me a while to get Noels 240 to be quiet enough to get under Sandowns noise limits.

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we went to put it back and could not get the cam wheel onto the cam, chain to tight. the timber wedge must of come loose and the tentioner had taken up the slack, tried to get it back in but after an hour had to concede defeat Sh#*%t.

I would say your tensioner has moved out to far an probably is now jammed at an angle against the timing chain , would suggest you take off the timing cover to be sure, yeah thats a bitch BUT "er" on the side of caution :)

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I feel for ya, just done one recently on a L24 rebuild.

balancer was a bitvh :'(

if the tensioner is as I think, take a pic to show what can happen, be good  visual info :)

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Hi Gareth. the same power as be for, like I said the top end was always good, the exhaust has cleaned up the middle bit, but no more power and alittle more torque. After talking to Peter I'm making about 10 more kw than your engine . I fixed up the tentioner today and put it all back together. Just need to change the oil. ( water got into the sump when pulling of the timing cover.) Then fill the radiator and turn key. Going to tryand get bigger muffler this week.

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Yes Salty, the tentioner. No pics this is a low budget thread, that's way over my ability. Took the zed for a drive tonight with the reducer in Pete, I thing it is a little quieter, defiantly the loudest at 4000rpm to 5000rpm but better. It has made bottom end even a bit smoother. Thanks Guys.

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