Weber 48's on 20XE

[Mike]

Banding some engine specs around & considered Weber 48's on a C20XE motor, any input anyone?

[Nick J]

Id speak to Martin kelson fella. sure he ran them successfully for years. I think its in the features section iirc.

Nick.

[MattBrown]

I'd like to know the same tbh, I dont know if to go 45 or 48

[Angus Closier]

I'd like to know the same tbh, I dont know if to go 45 or 48

Whats your spec? I Know people running 200bhp on xe 's with 45s....

[Spudly]

Speak to Rich (blue_peg) he also ran 48's on his loon for many years when it was xe'd and had 200bhp aswell, he blew a lot of them up but thats because he has a heavy foot lol

[blue_peg_16v]

As said I ran 48s on my xe and they were great had 42mm chokes in them (the biggest for them without machining) when cold if you floored it it would cough and splutter a little but that's to be expected once warm it was rappid and sounded awesome hence the number of engines I grinaded lol engine in mine had mild head work Qed cams Sbd exhaust fanny mold straight through 2.5in system head slimed a little verniers to stop valves hitting piston had to retard timing a little was rr at 196bhp could get similar figures with 45s tbf but the 48s were on offer when I bought them so couldn't refuse and in my book bigger is better lol oh and mike there was a guy selling a bran new pair on ph for 500 dco sp 48s barging a d same as I paid there normally about 360 each

[C612DNM]

48's will be fine. They will perform better on a stock engine (head & cams) with smaller chokes than blue_peg mentioned.

If you have some headwork done, and a pair of race cams, then 48's will be ideal as 50's are only really useful on a full sh*t motor that revs to three brazillion RPM and produces 300hp.

If your engine is only producing a mild 200hp, 45's are plenty - with 42mm chokes.

My choice of cams for the XE would be BD3 inlet and L1 exhaust - talk to Andy Burns at Kent Cams, he'll get them ground for you. Timed properly they should give you peak power at around 7000, but can be shifted to about 7500 with a loss of low end torque (no such thing as a free lunch!)

One thing to note - 48DCOEs and 50DCOEs are miles better carbs than DCO-SP's

[Will F]

I woudlnt say 200 (genuine) is mild on an XE!!

45s are fine for anything up to 230bhp - myths that 48s were better in terms of breathing were proved wrong by SBD in the mid 90s.

Anything more than 235 bhp (thats a serious spec btw) and you would presumably be rich - so be able to afford TBs - that can run anything up to 280 with a 45mm butterfly...

[philip]

48s are too big imo, 45s are a much better carb all round compared.

[MattBrown]

Yay, 3 contrasting opinions lol

Have too see what comes up then.

[Will F]

Yay, 3 contrasting opinions lol

Have too see what comes up then.

Thats the beauty of forums!

Have a look at SBDs website - not many can argue with the R&D they have done over the years...

[Mike]

Well Ive binned the idea of the carbs off anyway so contradicting input is of no matter anymore lol

Constantly shifting the goal posts of engine spec is a pain but we'll see what happens on the dyno I suppose.