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Posted: Sat May 12, 2007 8:37 pm
by JSF55
I did quite a bit of playing around with my carb last weekend, i went for the.86 19 31 in the end it really worked out fine, the only other thing i did was put a .89 in the secondary, oh and reset the float level and decreased the pump pressure, i found that with the engine not running the gauge was going up to 8 psi, and 5.5 running, i set it down to 4.5 psi running, john
Posted: Sun May 13, 2007 7:43 am
by sidecar
JSF55 wrote:I did quite a bit of playing around with my carb last weekend, i went for the.86 19 31 in the end it really worked out fine, the only other thing i did was put a .89 in the secondary, oh and reset the float level and decreased the pump pressure, i found that with the engine not running the gauge was going up to 8 psi, and 5.5 running, i set it down to 4.5 psi running, john
These carbs ain't too bad, their easy to work on. Its quite good that you've ended up on the same settings as me (apart from the secondary jets, I might have a mess with mine one day) It confirms that they must be OK.
Its worth getting the pilot screws right as your always pulling fuel from that circuit no matter where the throttle is so that can effect the fuel consumption a bit to.
Regards,
Pete
Posted: Sun May 13, 2007 7:02 pm
by V8cortina
Update.............
I've gone back to .86 19 31
It was running ok with .83 18 28 but the engine was getting a lot hotter than usual and there was a very slight flat spot on acceleration, that could have been cured by putting the accelerator pump back on the middle hole but I wasn't keen on the high temp, not overheating but at idle the oil pressure was very low due to the increased oil temp.
Strange how the smallest change makes a massive difference.
Posted: Sun May 13, 2007 9:47 pm
by sidecar
V8cortina wrote:Update.............
I've gone back to .86 19 31
It was running ok with .83 18 28 but the engine was getting a lot hotter than usual and there was a very slight flat spot on acceleration, that could have been cured by putting the accelerator pump back on the middle hole but I wasn't keen on the high temp, not overheating but at idle the oil pressure was very low due to the increased oil temp.
Strange how the smallest change makes a massive difference.
19 31 seems to be a winning combination
It is surprising that a small change in the number does make a noticable difference, but that's what I found. Its a pitty that there's not a few more needle sizes to allow more combinations.
Some clever Bod should start making them to order!
Regards,
Pete
Posted: Mon May 14, 2007 5:36 am
by minorv8
I have currently 86 jet and 68/57 rod in my carb. I have an Innovate WB lambda fitted. It appears to be quite nice setup, apart from full throttle acceleration when the mixture drops tyo around 10,5-11:1. I need to put smaller sec. jets in to lean the top end.
Another setup I have tried is 86 jet and 67/55 rod. It seems a bit better on 1/4 mile. Not too big impact on fuel economy.