How about a good starting point for this? It has 5 holes in the metering block and is currently set up as 1-blocked next 3-28 and the last one blocked. The carb works good with this set up but from what I have been reading I think it could be better.

This message has been edited. Last edited by: Kutsick,

You can try it with 28's in top and #4, plug the rest. It will probably need less jet, go down only one jet size at a time.

Thanks Mark thats what I was thinking but wasnt sure how it would effect the jetting. Right now it is 92/95 with a 24hs

Mark what do you think of the metering blocks with 2 large main jets and 2 small main jets in each block?

Staggered jetting? If it's needed it's OK, I would start out square jetted with no power valves.

No, the metering blocks that came with this 1450 has 2 smaller jets, like air bleeds that are to the outside of the main jets. Its like they could be used as a fine tuning tool or to flow more for maybe q16. Right now it is jet p92 and s95 but both metering blocks have 55`s in the other jets I am talking about. I have consider`d blocking them of and starting over.

They look like
these

The extra jets are the intermediate feed, and probably an Idle feed. If the idle feeds from the bowl side it's whats called divorced idle. Which means the idle fuel is pulled directly from the bowl, and not from the main well. This can make it overly rich at part throttle.

Thanks for the info. I changed the emulsion jets around and will see what it does at a race weekend.

Mark, on those BLP 5120 blocks, do know if the longer screws come with them? I know the arms are separate. Same gaskets also? I see you use a lot of them.

The small outer feeds are the intermediate feed. I try not to use any.

On the 5120 blocks you have to order everything. Bowl screws, mainwell plugs, mixture screws, emulsion set screws, 4-40's for the kill bleeds, and PV plugs if you get the ones with a PV provision. Pump arms I bend to fit.

If I already have the int air bleed removed and it has 55`s in the lower feed holes, can I use them to lean the carb out more?

Yes, 55 is big for gas. try .040's, do down as needed from there.

Thanks for all the help Mark. The emulison change help the consistency last weekend and now Im going to move the idle restrictors back to the top position and change the int restrictors like you said and see how it likes that. Thanks again Mark

Mark how small can I go on the int feeds? If I block them off like you stated before would I need to jet the carb up or would that just turn it into a 2 circuit carb?

Blocking the feed makes it 2 circuit, and that's fine if you can get it rich enough with main jet. Some cases the mainwells won't pass enough fuel, the fix is different metering blocks. You can open the mainwells up but you destroy the idle feed tubes in the process and have to replace them. Try making some .030 restrictions for the intermediate and go up on jet. where are you at now with jetting?