AntonAU

just for an update i got the 13b started now , all works good... i also bought a smokey 20B block from japland $1000 landed at my door pretty much so there's my performance motor.

back on topic any comments on these carbs?
http://cgi.ebay.com.au/SU-carbs-for-...323126001r8436

and just remember im in AU and no-one runs anything cept weber's in this country..holleys are NOT on the menu

trochoid

iTrader: (6)

For the 20B, no way in hell will it supply what that engine needs. SUs, while great carbs during the thier era, parts may be difficult to find and tuning can be tricky. Before buying anything, take a look at your goals, needs and expectations from the 20B. Going FI, while more expensive, eliminates frequent tuning and improves reliability, starting and fuel mileage.

If you do decide to go carb, you will need a custom made intake mani for whatever carb you choose. If you want a carb look and FI reliability, check out Tweak-It, I believe they are an Aussie company. You might find more info on AusRotary.com for possible choices.

AntonAU

ahaha nah for the 20b ive got twin 53mm DCOE webbers, the Su's are for the stock 13b i have now

and interms of fuel consumption im building a RBridgeport 20B consumptin isnt something im worried about

trochoid

iTrader: (6)

Since those carbs and intake look to be a DIY project, I'd avoid them. I have yet to hear of anyone here on the forum still running SU carbs. Those that have mentioned using them in the past and could tune them well were happy with them. Before asking for advice or deciding on a carb setup, what are your porting plans?

AntonAU

for the 13b that im putting into the car (its in a s1 but its going into a rx4 ) stock nothing except an exhaust, and mayby those carbs mainly for ****(look) factor, the 20b will be running twin webers so im only asking about a stock 13b, i not worried about DIY look in au we rarely use off the shelf bought parts, im fabing my own exhaust aprt from cat & muffler, tuning isnt much of an issue but im more concerned with it leaning out + fuel flow etc on 13b up to 7500/8k rpm

trochoid

iTrader: (6)

I have the dual Weber DCDs on my 1/2 bp-1/2 sp 12A. That's 4 - 1-1/2" throats with a pair each of 28 and 36 mm venturi. That size venturi was Rotary Engineering's choice for thier 13B sp engines, the 12As sps came with 25/32 mm venturi, iirc. Your concern about top end leaning out may be valid based on that and the SUs being single barrel carbs.

AntonAU

might have to talk to some of the older rotary people they might have more experience.... even thee days webers are starting to become a bit of a mystery to some of the mainstreme workshops due to the older generation starting to come to end of their working life....

it realy comes down what has been done to the Su's to modify them

if anyone has any input would help just for further clarification its stock port with just an exhaust ...


for the 20B i chose the dcoe's because firstly i bought one that came off a 13B PP racing car i went hunting and found ne thats very similar just needs some mods to be brought up to the first one specs, i will get them both rebuilt when im closer to getting the 20B running, but im assuming that 2 of them for this spec for a super large bridgeport 20B should be adequate for the mani i will run a dyson injection lower with doce weber adaption uper to fir the webers too.

Kentetsu

http://sterlingmetalworks.com/the_sterling_nikki.htm

AntonAU

sorry man not interested in that if im going to run a nikki im just going to leave it stock was more intereste din the SU's for the look than performance increase..

broke7

iTrader: (1)

demending on your budget a 3 barrel ida used on 911s my be a nice setup

OneRotor

iTrader: (3)

I'd stay away from SU's. As trochoid said, they could be finicky. It could be to the point where the car won't run.

For the 20b, I would worry about the Weber's not flowing enough for the top end.

PercentSevenC

I've seen a few 20Bs with this setup. Looks very nice.