Weber 151 jet needed for the 1600 lotus twin cam (elan 1968)

[Newsax]

Hello,
Need help here

I would need to know which jets to use in a twin 40 Weber 151 for setting it with my lotus elan +2 from 1968 with a TC?

Thanks you!!

[elans3]

To start with, just transfer the jets from your 31's or 18's. They all transfer with no problem.
The only thing I've found after putting 151's on a TC is that sometimes (and not every time), the idle jets need to go up one notch. As they're emission carbs, they sometimes aren't spot-on using the idles from the earlier non-emission carbs.

[Newsax]

viewtopic.php?f=50&t=47308

I found second hand Werber 151 to replace my current not original one.

They were Jetted for a caterham with 1600 8v opel, and I was just trying to know if it would work "as it" or if I will need to update jet, and by what

Thanks

[elans3]

It will not work for an Elan. In that case, you will need to change all. or almost all of the jets, which can be expensive.
We need to know if your car is a standard 105bhp, a118 bhp SE , or a 126bhp (big valve engine).
Then I can tell you which jets you need to buy / change.
Some jets were different in the above three engines..

[Newsax]

Don't tell me that

It is a standard one 105 bhp, TC from elan +2 1968

[ianthomson72]

The standard engine in a plus 2 was in S/E tune to offset the extra weight .

[Newsax]

Ok the SE 118 , sorry for my mistake

[Newsax]

Maybe I can took back the jetting for the current one fitted (likely Tipo 34 / 35's , or 90/91) ?

[elans3]

Yes, check the 34/35's to see if you have any of the jets shown below, inside them, it'll save you a bit of money.
So, an SE engine needs the following, to be checked against what you have in the carbs already :-
Chokes (x 4). Normally 32mm, but generally that produces a "flat spot" or "bog down"at progression, (even when first introduced, Lotus acknowledged this, and provided a "fix" in their Workshop manual, to change the chokes to 30mm, and change the air corrector jets from 150 to 200), resulting in the following :-
Chokes 30mm x 4
Main Jets 115 x 4
Air Corrector jets 200 x 4
Emulsion Tubes F11 x 4
Idle jets 50 F8 x 4
Accelerator Pump Jets 40 x 4
Needle Valve 175 x 2
Back bleed jet x 2 Should be "around" 50, if you have 40 or 60, it won't make much difference.
Once you have these fitted to the 151's, this should get the engine running ok

Do not try and run the engine with anything different to those shown, for any length of time.

Remember that the engine should be hot (thermostat opened and running at Normal Operating Temperature), before balancing and air / fuel mixture adjustment.
This is the time when you may find that the idle jets may need to go one size up.
Hope that helps

[Newsax]

Thank you

[Newsax]

Is this a good kit for my +2 and 40 Weber 151?
https://www.ebay.co.uk/itm/274300852190

I will still miss some jet, that I can hopefully find in the 34/35 currently fitted.

Otherwise any sources when I can get those?

[elans3]

Yes, you'll need two of those, but it only provides the needle valve.
If you need more jets, I can only give you UK suppliers,
Webcon in Sunbury, Middlesex, or
Fastroadcar in Newport, Gwent.
I have used Fast Road Car for the last 12 years, as before I retired, I used to buy, refurbish & sell Weber carburettors.
Others like Burton Power stock them, but tend to be more expensive, and may not have all the sizes, all the time.

[pharriso]

Otherwise any sources when I can get those?

I use 2 guys that sell on eBay, one from the Czech Republic & one fom Italy:

CarbDeal https://www.ebay.co.uk/str/CarbDeal?_trksid=p2047675.l2563 & alfa1750 https://www.ebay.com/str/ALFA1750S-CARBURETORS-PARTS-STORE?_trksid=p2047675.l2563

[Newsax]

Thank you for the adresses,

Sounds nice thanks !!!

[Newsax]

Got everything from Carbdeal on ebay !

My 2x40DCOE151 are now ready to have a full rebuild and new Jetting for an elan +2

Thank you for your help, will post pictures in Sven original post (viewtopic.php?f=51&t=46215&hilit=sven) when I do it