For someone who is really determined to make a Weber 45 DCOE work on a A-series engined Mini, you could start by getting a copy of David Vizard's "Tuning BL's A-series engine." A whole section on Weber / DellOrto sidedrafts for A-series engines and even a list of tube/jet etc. selections for 9 engine combinations he tried the 45 DCOE on.

 

 

I had a mini, many years ago, with a weber and a free flow muffler in the back. It had a Spreen's built engine w/cam that came on at 3500 rpm. It was LOUD. Stereo noise with the induction and exhaust. 

JohninCM:

Life is too short!  
??

I poked around the WayBackMachine and got close to the original post in this thread but not close enough. Have a go for yourself and see if you can hit pay dirt ...

https://web.archive.org/web/20140918013044///www.minimania.com/msgthreads.cfm

8 yrs........not a record, but impressive nonetheless.

You need to be very determined. . . . 

Jameshaydn:

This thread is 8 years old and (unfortunately) the contributors to it have all moved on from here.

Gday there Jeff. Great read. Love to see the graphs but cant open them.
Any chance you can help me out? Maybe send them to my email>
Let me know if you can.
Cheers

Can anyone send me the link to the original post? I've been searching but cant seem to find it.
Cheers in advance
Jameshaydn

Impressive gain and fantastic write up Jeff!  It's really nice to see dyno charts.  Thanks for sharing.  

J

I'm with cooper tune, water off a ducks back, water under the bridge, turn the other cheek, be the bigger man..... You have an interesting post going >

Gee that's no way to be. CC is just doing his thing. You are providing interesting info. This is the kind of stuff we should be talking about. I'm trying to figure out what I can do to improve my HIF 44 set up. I want to mount an O2 gauge and vacuum gauge along with my tach. I run everything lean at idle no load no harm. I'm playing with a hot 850 on a single 1 1/4 SU. Bored .020, zero decked, 510 Cooper S camshaft, 150 psi all cyls. Head chambers opened up 1100 valves and .100 surfaced from head. Steve (CTR)

I figured it would happen.  Since CupCake couldn't keep his mouth shut and had to bash me with his "if the tune on the HIF6 was any good" comment I'm done posting on this thread.

Yes Steve, I'd be happy to share my Weber calibration, but not here on this toxic forum.

The only significant differences between the two setups is with the SU the fuel has to change direction in the manifold on subsequent intake strokes and with the SU the mixture has a sharper corner to negotiate in the intake manifold, so there's no way there should be that much difference, if the tune on the HIF6 was any good. My guess is a BDK needle is required in the SU based on your motor description.

Thanks for the added info. I spend hours looking at needle charts and they are not in mm. I talk with Joe often and try and buy 3 needles not already in my collection when I do. I guess you have not seen AC's video on profiling needles. I'd be hard pressed to bill someone for 50 hours and then tell them they needed to start over. I guess it does happen. I have a car in shop that was converted from FI to Weber which did not do well. They charged $4500. and suggested he get an SU. Let's see exhaust was hacked up, firewall hacked up, wires chopped to bits, fuel system half stripped out and balance hanging from zip ties. 

I realize doing your own allows for freedom to play. Do you happen to want to share your weber calibration? Also is the 12 to 12.5 for max power? I try to shoot for 13.8 to 14.2. Not always possible but still trying. Steve (CTR)

Great info and pictures. It also shows me the inlet manifold size I should use if I want to have any kind of dash in the old race car. (It came with a long Weber intake) That explains the sheet metal dash that was screwed to the dash rails.

Also shows the importance of using a dyno to dial your engine to it's peak performance.

Thanks for sharing.   

To quote Richard Rawlings " Let er rip potato chip "

Air2air - yes, it was an HIF-6.  Is that the same as an HIF-44?  Anyway it was one of the newer SU HIF series carbs with a 1-3/4" bore.

Steve - It's got a Megadyne 266 cam, so a very street friendly low power cam.

Regarding the SU needle profiling I spent about 50 man hours between myself and a friend profiling a needle.  It was a project I very much enjoyed since I could really start to understand how the needle profile affects the carb operation.  The end result was a very flat air/fuel ratio that hovers between 12.0 and 12.5 nearly everywhere (see dyno chart below) in the power band.  The needle that came in the car from the engine builder was a BBC needle which was rich at idle, lean at cruise and accel, and pig rich at WOT.  After studying the profiles of around 150 needles I chose a BCE needle to profile because it was closest to the what I needed for a starting point without being too rich anywhere (for those that don't know, needle profiling is the process of changing the taper on the needle by removing material at specific locations which enrichens the mixture at the corresponding operating point).  I did a lot of research about needle profiling, which I learned is an old school art that no one really does anymore except for turbo Minis that require odd profiles.  I wouldn't do it again as it's very much an inaccurate science - akin to shooting in the dark.  I definitely wouldn't do it on a twin carb setup.  My results were exactly what I was wanting and I'm very glad I went through the effort.

Here's a simple graph I made that shows the changes I made to the BCE needle:

Since I didn't post it before, here's a dyno sheet of the HIF-6 carb that includes the air/fuel ratio (the result of my needle profiling) at the bottom:

I don't see any mention of what camshaft you are using. How much time and how many needles did you try with the SU? How many calibration bits did you buy for your Weber? Reason I ask about the cam is my 1360 Cooper s engine is running a Reed Mega Torque and a HIF 44 and will idle at 650 but it's a little lumpy. The correct needle for mine will be a custom profile. Been talking to AC Dodd about what I'll need. I have a couple of short intake kits with 45 DCOEs recently removed from early 90s minis if anyone else wants to go this route. Buying already tested will save a bundle. My Weber collection has gotten out of hand. I have jets, tubes, chokes, aux vent. ram stacks, linkage and intakes. Not just a couple of each but everything to cover a mini from std 998 to full on vintage race unit. Not interested in selling parts just a couple of ready to bolt on kits. Steve (CTR)

Jeff, one of the best technical posts I've seen on here.  Concise and gets right to it.  This was an Hif 44?

Damn, good info Thanks

800 RPM idle.  FWIW I couldn't ever get the SU to idle well below 1100 RPM.