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I just got back from a night ride. Halfway into it, the 1275 in the 65 goes to smoking badly. Not all the time, sporatically when I am at speed, and when I am coming out of a corner on acceleration. I dont have the original PCV valve on it, but one of those later ones about the size of an inline fuel filter. I have it fitted between the can on the timing cover and the vacuum port on the intake. I have it fitted so that the intake will draw through the PCV out of the can.... MORE
Nigel states in part...."I think you'll agree the mildly tuned conversion (old BL Stage II Tuning Sheets) makes for a pretty nippy car!" Absolutely, Nigel... Yep, very peppy!! That flowed head has 19cc combustion chambers instead of the standard 21cc. Brings the CR up to about 9.75 to 1 I believe, more or less. Notice the difference in the top end acceleration in 4th despite no cam change, due to better "squeeze" and breathing, both in and out. Very impressive. And your 'lazy' remark? Exactly why I looking at the single 1.75 as well, Nigel, and thinking of selling... MORE
Bob Thanks for this - most interesting. I have also been looking at various carb setups to replace the existing 2 x 1 1/4, mainly I have to confess because a single carb is easier to set up, and tune and no need to balance the pesky thing - yeah I'm lazy ; ) I've looked at the Weber 45DCOE and 40DCOE, but for my application on a virtually stock 1275, I don't see the benefits. The setup I cam considering is the MG Metro carb - the SU 1.75 HIF on a decent manifold - that may well... MORE
Yep, Nigel, I did set it up on a chassis dyno in it's application on my PO'd '74 Vizardized RWA Midget which got 90hp at the rear wheels. God, I loved driving that car.....lowered, with flares for the Yoko 008R 60 Series 185's. Had a 2" exhaust from the large bore LCB through a "reversed" glass pack. Great sound and went like hell! Back then I was doing a lot of highway driving commuting to my domicile in LaGuardia from Stamford (60 mile round trip) at least once, and sometimes twice a week. With the stock ribcase and 3.7... MORE
Hi all, found this on the BBB list, someone out there in Yankee land might be interested. I am, but too far away !! It looks like this guy knows what he is doing, he's certainly got all the right parts IMHO regards alan Posted 17 February 2003 at 03:55:48 UK time Brust, Sacramento CA, roethler@... I am replacing the a-series MG with an A-series toyota (4age). This summer will be the big swapout and I'm wondering if anyone is in need of a complete 1275 driveline: 1275 +.030 8.8 pistons CAHT11 LCB Header ported head alloy valve cover... MORE
Mark, if you think about it in practice, each pair of cylinders will only 'see' one of the 1"s. It's highly unlikely the air can flow one direction through the manifold balance pipe, then stop, then reverse flow to go to the opposite port. And do it 3000 times a minute. Regards David "David Jacobs" 19379... MORE
Nigel states, in part..."fit some aluminum panels and watch it zoom.....fitting a bigger carb ain't gonna help..." Oh, yeah, Nigel...wanna bet? Just watch this!! :):) Your way will work but look at the bucks!! And I got a 45DCOE sitting on the kitchen floor from my old, PO'd Vizardized '74 Midget! :) I got a Cooper S cam with 1.5 RR's and the better flowing aluminum head running a med bore LCB through a 1.75 RC40 on bascially the stock twin 1.25 set-up (but H6 needles and red springs). You gonna tell me this set-up ain't dying for more... MORE
Just perform all the flow modifications to the inlet manifold and SU's as described by Vizard! This should be enough to supply an engine (of 65 - 85 bhp) with enough mixture. And as said before; the engine is only seeing 1 carb in case of a dual carb setup with a more or less standard manifold. So it's incorrect to assume that a dual carb setup doubles the capacity of one 1 1/4" SU. The carb modifications as described by vizard should get you the performance (in terms of flow) of an unmodified 1 1/2" SU (step from... MORE
Too many variables here, Alan, though I appreciate your input. The compression ratio and intake valve sizes of the Metro, along with the fact it's cam profile is a far cry from the standard 1275 and is even a step up from the Cooper S makes this comparison too murkey for me. The Metro is more a production street ralleye vehicle in disguise.......while actually it's the carbureted hotrod of the production 1275 set, really...and what part of that would be the 1.75 carb? And you can bet this single 1.75 was chosen more for smoothness, ease of maintenance and... MORE
Hello again, Regarding the performance questions about carb conversion to 1.75" .... I can't really comment on the carb alone as my Midget also has a ported large valve MG Metro head, K&Ns, LCB exhaust and all the rotating bits balanced. Goes like stink and gets easy 35 English mpg. Does however use lots of oil. Can't have everything. Next step build all the go faster bits from my engine onto a 10,000 mile old Morris Marina block. Regards Mike Mnemonic (UK) "Mike Mnemonic" 19311... MORE
Well Bob. . . ; ) If we're talking stock, unmodified in any way, bog standard 1275 A Series engine, with a factory standard exhaust to be honest IMHO there's little to gained from switching from the factory fitted twin 1 1/4 SU's, to a larger carb, over and above the fact that a single carb is easier to tune and a very slight increase in power/hp in the very top rev range, which as you rightly say has little/no bearing on regular street driving. However, if we're talking tuned 1275 A series, bored out/ported/bigger inlet/exhaust valves/stage 2 or... MORE
Mike Mnemonic in UK.... Understand "comparison" in your case is not possible for cause...thanks for response anyway, mate..appreciate it. You did not state overbore of block, Mike, however, higher oil consumption in overbores beyond "60" is not unusual where high rpm's are consistently utilized in any event, due normally to some "bore-flex", even when rings and valve/guides are reasonably "tight". Also, exhaust "reversion" with longer period cams will cause some "sucking" back into the cylinder if valve seals are not used in the exhaust valves, as is normally the case with stock or relatively "short duration" street grinds. Good... MORE
Probably right Captain, There is some loss in air flow with a 1 3/4 versus 2@1 1/4, but not a lot: 2.41 cu in. versus 2.45. If the 1 3/4 manifold does not have equal length runners you might loose a little more. Of course, you wouldn't have to worry about your carbs being out of sync/balance either. I guess you pay your money and take your choice. Mark Howard "Mark Howard " 19279... MORE
I'll tell you Mark Howard... I haven't met anyone who has done the 1.75 conversion that can tell me: "My stock 1275 used to do 0-60 (or the quarter mile) in blah, blah seconds (and blah, blah mph). Then I converted from the stock carb. set-up to a single HIF44 with a BDL needle and Titan manifold, and cut 1.0 second off that 0-60 time (or quarter mile at blah mph)." I don't know, the fellows from the UK are 6 hours ahead and posted around 6:00PM my time. Maybe they went to sleep before I posted my question?... MORE
HS6 or it's modern equivalent the HIF44 is even better. I'm just putting together an article for Mascot on my HIF44 / Titan manifold conversion. Jim, whereabouts in Hampshire are you? I'm near Petersfield if you want to see my conversion 'in the metal'. Jeremy jeremy.cogman@... 19251... MORE
Hi, Mike Mnemonic in the UK... I've been looking for somebody who has done this conversion on a more or less stock 1275 to provide some feedback on performance increase over the stock double 1.25 SU set-up. I know the application is of course, far easier to tune and also know from my experience with my Judson "unbelted" that the increase in smoothness and economy with "one" larger throat is truly excellent. But what say you in terms of performance "increase" over the normal stock set-up, with the understanding that one of the biggest "blocks" to decent "flow" is... MORE
Jim, Throw it away and get a 1 3/4" carb and manifold from a MG Metro. The manifold in these cars is one of the best in terms of air flow, it is also water heated and separate from the exhaust manifold (other Metro's may not be). As standard, it won't quite fit under the Midget bonnet. Get an engineering firm to modify the head end to make it angle down a bit. The carb only fouls the bonnet by mm's as the ding in my bonnet will ably demonstrate. I've done this mod on my 73' and it... MORE
Howdy !! I'm looking for a used exhaust manifold for my '72 RWA 1275 engine. The previous owner cobbled up a cheap header exhaust system and welded in a straight pipe that is about to rot thru. I would also like to locate the exhaust pipe flange that bolts to the exhaust studs since only one (without the other) does me no good... Thanks for any leads on these items... ps: any leads to a decent pair of seats (no color preference) would also be useful... Mike P. Buffalo - NY "mpelone " 19235... MORE
Jim, I think you will find that Minis from about 1970 - on used a single 1 1/2 SU, so there should be plenty of them in salvage yards. The manifolds are integrally cast with the exhaust manifold, but can be sawn off and used with your existing ex manifold. Even better might be to find a carb/manifold from a Metro (HIF 6), and saw that free from the ex manifold. In addition to Oselli, 1 1/2 manifolds are made by Janspeed and Howley in the UK. "Jeffrey Holmes " 19236... MORE
Jim, you could try using a Mini manifold, though if you get a standard one, you might need to cut the exhaust half off it, as a lot were combined in one casting. The standard MG Metro inlet manifold is a much better design, but that's for a 1" carb so the studs may or may not be in the right place for your carb. Failing that, there are a multitude of aftermarket ones available. Why do you want to try a single 1" carb anyway? Regards David "David Jacobs" 19225... MORE
G'day Brad You need a line with a 3/8" UNF male fitting, and a double flare (or "ball" flare"), on both ends. Is this your left hand drive or the right hand drive car? If RHD, then no, the brake line will not reach. The original clutch line was 57" long - remember it should have a double loop approx 2" in diameter, to take up the engine vibration and stop the line from fracturing. The brake line from the 4-way junction to the L/H front wheel is long enough, but has the wrong fitting on the wheel end... MORE
FYI Up until 1275 slave cylinders, the clutch pipe is a 3/16 line with single flare (aka bubble flare). The male pipe nuts are 3/8-24 thread. The Beck/Arnley part number for the line (60") is 073-1085 the Dana-Weatherhead is (S)B360 the Everco Bundy-flex is B3600. 60" is the longest these companies offer in their ready made selections. (they also have 8", 12", 20",30", 40", 51") Loose nuts and unions are also available. HVD Peter C "Peter C." 19095... MORE
Simplest fix is to disconnect the 2 hoses going to the heater box adn connect them together with a short piece of pipe and 2 clamps. Otherwise yo u could install a new valve in the inlet hose to positively SHUT OFF the inflow of hot water from the block. David A. Stevens Jr. Utilities Engineer II NYS Office Of General Services Sheridan Avenue Steam Plant 79 Sheridan Avenue Albany, NY 12210 "Stevens, David" 19020... MORE
Yep, Willy..... 1960 or '61 MGA roadster red with tan (or "biscuit:? heh, heh, heh!) interior with solid wheels and full whitewalls. Cap'n Bob's version was Old English White with a black interior, painted wire wheels, and a much sexier sounding Abarth muffler. And while I definitely like girls, Elvis was one good looking guy in those days, no doubt about it.....guy had so much going for him. Mentioned this to Kate of Kate & Gary fame (aka "bobcat Kate", which is my new pet name for her!) the other day when I "taped" some of the car parts... MORE
Guy Not sure if this is any help but the UK Moss parts catalogue I have lists that part as 'Pipe - Tank to pump flexible hose' part number AHA7381Z and costs =A38.81 GBP, approx $13.20 USD. It's the part as used for the later Spridgets too. Nigel "amukdigiphoto " 18833... MORE
