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Posted: Tue Apr 05, 2016 3:57 pm
by sidecar
Post up your setup if you want my opinion on it! :lol:

Also if you are bored have a read of this old gumph that I wrote ages ago. I now think that some of it is a 'bit' wrong, i.e I no longer think that all the sizes of RV8 can be setup with the same carb settings. (The web is full of un-truths, so mine are a drop in the ocean!)

The info that I wrote will tell you how the carb works if nothing else....

http://how-to-build-a-pilgrim-sumo.wiki ... ing-system

Posted: Tue Apr 05, 2016 6:02 pm
by moppit
me?
My setup is a 3.5 new build from an SD1 block I think , typhoon cam, ported and gas flowed heads, Eddy 500 (1404?), JWR Dual plane manifold, tubular headers, JE front cover/oil pump, Mallory electronic dizzy, Mr Gasket low rider air cleaner (all I can fit in!). Car is an NG TC (circa 750kg) so not much to shove along.... Front and rear hoyle adjustable suspension, discs all round when I need to stop.

https://onedrive.live.com/redir?resid=1 ... folder%2c

Posted: Tue Apr 05, 2016 6:40 pm
by sidecar
Hi Moppit, no text in your last post?

Posted: Tue Apr 05, 2016 6:45 pm
by moppit
Dunno what I did wrong there - tried to post some links to pics but ended up with a blank post?


My setup is a 3.5 new build from an SD1 block I think , typhoon cam, ported and gas flowed heads, Eddy 500 (1404?), JWR Dual plane manifold, tubular headers, JE front cover/oil pump, Mallory electronic dizzy, Mr Gasket low rider air cleaner (all I can fit in!). Car is an NG TC (circa 750kg) so not much to shove along.... Front and rear hoyle adjustable suspension, discs all round when I need to stop.

will attempt pics in a separate post

Posted: Tue Apr 05, 2016 6:46 pm
by moppit
some pics..

Image

Posted: Tue Apr 05, 2016 6:55 pm
by ged
Fixed for you :-)
https://onedrive.live.com/?authkey=%21A ... E9252DE019

& very nice by the way.

Posted: Tue Apr 05, 2016 7:16 pm
by moppit
Thanks and thanks! So what is the process for pics? :oops:

Posted: Tue Apr 05, 2016 7:24 pm
by sidecar
Very nice!

In picture 2 I can see the air filter stud, (I zoomed in on the pic), so what you might say! well it is very short, this means the the air filter lid is very close to the top of the carb. If you look at the primary side of the carb you can see that the choke is housed in a raised section of the carb, I bet you will be lucky if you have 10mm clearance which in my humble is not enough. This will mess up your carburation. The choke is useless on these carbs it will foul the plugs if you use it, if i was you I'd remove it then cut the choke horn off the carb. I've done this on a few carbs and it helps the primary side of the carb to breath better. Just for your info my air filter stud is around 75mm long!

Er, your throttle return spring will put a lot of load on the primary throttle shaft, if you think about what happens when you press the throttle the cable might put 2kg of load on the top of the throttle arm, the spring will counteract this with another 2kg of load, that's 4kg of side load. This causes the carb body to wear out which results is all sorts of carburation issues. If the spring is placed in line with the throttle cable on the top of the throttle arm so that the spring is heading off towards the front of the car the two loads cancel each other out, the result is 0kg side load on the throttle shaft and carb body! :D

Posted: Tue Apr 05, 2016 9:05 pm
by moppit
sidecar wrote:Very nice!

In picture 2 I can see the air filter stud, (I zoomed in on the pic), so what you might say! well it is very short, this means the the air filter lid is very close to the top of the carb. If you look at the primary side of the carb you can see that the choke is housed in a raised section of the carb, I bet you will be lucky if you have 10mm clearance which in my humble is not enough. This will mess up your carburation. The choke is useless on these carbs it will foul the plugs if you use it, if i was you I'd remove it then cut the choke horn off the carb. I've done this on a few carbs and it helps the primary side of the carb to breath better. Just for your info my air filter stud is around 75mm long!

Er, you throttle return spring will put a lot of load on the primary throttle shaft, if you think about what happens when you press the throttle the cable might put 2kg of load on the top of the throttle arm, the spring will counteract this with another 2kg of load, that's 4kg of side load. This causes the carb body to wear out which results is all sorts of carburation issues. If the spring is placed in line with the throttle cable on the top of the throttle arm so that the spring is heading off towards the front of the car the two loads cancel each other out, the result is 0kg side load on the throttle shaft and carb body! :D
wow! Thanks this is amazing. Appreciate the help.

Posted: Tue Apr 05, 2016 10:10 pm
by southernd
What a gorgeous car, it looks stunning, lovely job.

Posted: Wed Apr 06, 2016 12:42 pm
by moppit
southernd wrote:What a gorgeous car, it looks stunning, lovely job.
Thanks! We need more pictures of everyone's projects on this forum....shame they are links only.

Posted: Thu Apr 28, 2016 8:58 pm
by southernd
Quick update :)

I decided to buy a new Edelbrock 1404 as was still getting small issues with initial response and intermittent stuttering.

I did the job in around 40 minutes, very very simple, I can't believe how easy it was. It started straight away and runs beautifully. The rods are 67 at the moment which seems a little rich, I'll drop to the 62/52 which seemed to work best.

I'm going to do a post mortem on the old carb this weekend, great way to learn about them and handy to have a spare for when this ones had its day :) I've really enjoyed learning about carbs, they're not the black magic people make them out to be, just time and patience :)

Posted: Thu Apr 28, 2016 9:18 pm
by southernd
Image

Posted: Thu Apr 28, 2016 9:32 pm
by sidecar
If you drop the 62-52 rods in and leave the same primary jets in place it will be loads richer on both the cruise and power circuit, not leaner. :wink:

Posted: Thu Apr 28, 2016 10:10 pm
by southernd
So say 67/56 is leaner tab 62/52?