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There is a very good chance that I will be able to buy a complete used set of dual carbs with manifolds and linkage super cheap (<$100), in the near future. (I did a friend a big favor and he has a huge cache of used VW stuff.)
MiGi is a stock 1970, 1600cc single port engine, I just rebuilt and it’s running perfectly. SVA distributor (but have a new 009 in my parts drawer). Currently has the Solex H30/31PICT carb. Running a 3487 exhaust, stock cam. But, – I got beat at the stop light by a MGB the other day. (Don’t know what was under his hood.)My questions are:If I have a choice of used dual Webers or Solex or Delortos, which to go with. Also, what size carbs for my 1600? I don’t think that there will be any interference problem.Or, should I just pass and be happy with my current configuration since without bigger jugs, hot cam and extractor exhaust, you really can’t get any more out of a 1600sp??Would dual carbs (alone) really make enough difference to be worth the effort?Retired finances and health allowing, my upcoming winter project will be to build a big bore (MGB beating) fire breather on the cheap. I like having a daily driver with a complete, hairy monster in the corner of the garage, ready to plug in (engine swaps simply don’t get any easier than a VW powered Daytona MiGi).Roy,
My Karmann Ghia had dual Dellorto 34mm carbs. Don’t know how much HP the duals added but they sure looked better. My friend ran his 74 Ghia with stock 1600 dual port up I-75 at an even 80 mph from middle GA to Chattanooga with no problems. But I think your problem may be the single port. Not certain but they should work okay. For that price I’d give it a try. If you get the Dellortos (sometimes called baby Dells) let me know. I’ll send you the extra rebuild kits I have.Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackI should add that the MGB was one of those ugly big black bumpered mid ’70’s smoggy 70-85hp models that outweigh me by about 500# or more. ….driven by a Danica Patrick look alike.
Well if the driver looked like Danica Patrick I can see why you’d want to keep up with the MGB.
Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The ShackYeah, I did, but I regret it. This was hoped to be a serious question about the +’s and -‘s of dual carbs on an otherwise stock 1600cc sp VW engine. Only Allen has offered an opinion so far.
(Unfortunately, the Danica look alike lives somewhere around here and I may meet up with her again at a stop light someday.)I have a progressive 2 barrel EMPI carb on my Roadster. Works very well. Dual carbs should be ok
Dick, What I am really looking for is before and after driving impressions. Did you upgrade to the EMPI? If so, (I realize that this is subjective) what engine/cam/exhaust do you have and did the carb give a noticeable improvement?
Sorry Roy, It had the EMPI carb on it when I bought it. Engine is a 1800cc, not stock. I can’t be much help to you.
I don’t know but I’ve read….
Single port will restrict, but the extra flow from the baby dells will give you a bit more top end grunt than a single PICT 31, and you’ll keep that low-end throttle response you get with the SP head (assuming you take the time to set it up right). These guys here say go for it.
Kid Speed says duals will actually give better mileage when tuned right. (?)
But, yeah, really: to get a real noticeable improvement you need new heads with a bit of a port job.
All that said, a stock B 1800 should not be much faster than you right now, all things equal. The Black Bumper cars weigh about 2,700 lbs–which is about 1,000 lbs more than us. The engine makes maybe 90 horse. That’s 30 lbs per horsepower.
Our cars, assuming 50 horse and 1700 lbs, lug 34 lbs per horsepower.
BUT. . .
Assuming you weigh twice as much as Danica, we get 2800 lbs/90hp for the B–31 lbs per horse, vs
1900lbs/50 hp for Roy–38 lbs per horse in the white car.
So she’s got 22 percent more potential acceleration, on account of she’s lighter! Trade cars and maybe she still wins.
Thanks Ed,
That is more like what I was hoping for. I had read some of what you referenced but you found some links that I had not. Sounds like Bugbits doesn’t like single port heads. Bummer! I did a “bit of a port job” on my heads when I had the engine apart last winter and my single port heads have oversized valves.Am really disappointed to hear that your horsepower/weight analysis concludes that Danica gets away. ….but maybe I can keep her in view longer and maybe that would make the dual carbs worth it??? eh?Here’s what got me thinking about it: Where am I wrong? VW went to dual port heads about 1971 with no other changes that would effect power that I am aware of except that the bigger fan which would probably subtract, not add some to hp at the wheels. Evidently VW thought that the intake on the 1600 was restricting flow and therefore they could get more fuel mixture into the chambers with dual port heads and bigger pipes in the intake manifold and therefore more laminar flow. The key here is that they seem to have thought that the weak link was the intake manifold since I don’t think anything else was changed. Dual carbs with their short little “manifold” pipes should reduce that problem at least as well as a single carb on a dual port manifold. Yes??If you guys can help me squeeze a few more hp, maybe I can get a picture of Danica’s front bumper. I hope that later this week I’ll get a look at the carbs that I am thinking about and that may help me make up my mind. (I hear you, with a puny 1300, that size does matter, and up to now, I have been trying to get my stock equipment to work as well as possible, thinking that staying power was important. Maybe it’s time for more surgery. Don’t forget that I don’t, and likely never will, know what is under Danica’s hood.)(Of course,… I could just lose a few pounds. Trading cars is not an option.)Roy,
I’m not an expert on this. But asked a friend who has been playing with VWs for years. His comments:
He can run a set of 34mm small Solex carbs or a single Weber
progressive 2 BBL on the 1600…however there would be little change as a single
port runs out of steam at 60 – 65 mph.Best to keep the stock Solex in tune along with the timing and
valve adjustments.Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
Just to be clear, My car has single port heads and an indeterminate displacement (1300 originally, according to the number stamped on the case; probably embiggened to 1500 or 1600 circa 1980 for the install into Bridget).
She’s got a Solex PICT 34 and an electronic ignition, regular muffler (3487), j-pipes, generator & etc. Old school tins (not the dog house). No oil filter or anything.
The engine spins to 5k without protest, and does not seem to “lay down” or lose steam. I don’t think it’s prudent to rev higher, but I’m sure I could, maybe even in 3rd gear. There is room under my right foot when cruising at 70-75, flat or even a bit up hill. There’s a nice steep one just south of me that I regularly top doing 60 or a little better (speed limit on the road 50-55).
I’ve had her above 80 once or twice but I’m not as stupid as I used to be & so I lift.
So this 65 mph claim would not seem to hold water, at least when speaking of a TD Replica.
Ed, It sounds like we have the same engine judging by performance. I expect that your engine has been “embiggened” (:D) as you suggest. What paper/magazine do you write for anyway? I think that I might enjoy reading some of your stuff.
If you want a pictures of Danica’s front bumper, check out the godaddy.com site.
Bill Ascheman
Fiberfab Ford
Modified 5.0, 5sp., 4:11
Autocross & Hillclimb
"Drive Happy"Guys, I decided to let the dual Webers and single port manifolds that I had a lead on go. Y’all have convinced me that if I want a “go fast” engine, I need to embiggen (Ed, I just love that word) my engine. So, I’m thinking of buying a 1971-73 dual port and embiggening until I run out of steam or money as my winter project. This is the same project that I was going to do last winter but MiGi sprang an oil cooler leak and I ended up just rebuilding my old engine. If any of you have any head to head before and after comparisons, even if only seat of the pants, I would be interested. Also, if you have any other helpful sugestions of the whatever you do, don’t XXXXXXXX variety, those would be helpful also. (I am concerned about summer overheating so, don’t want to get so big that I have to worry about that.)
Roy,
I went form a 1600 to a 1641. I felt no difference.
Before my recent problems, I put about 30 miles or so on my new 1776, dual port, dual Solex Pict 34 carbs.
My seat of the pants reaction, the 1776 is a great upgrade. It had just enough extra power and torque to make things fun. Once I figure out the current issues, I’ll give you a better review. But I think I will be VERY happy with the 1776.
I believe 1776 is as far as you can go with machine work on the block.
Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica RoadsterIf you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)
Thanks Paul, That is the sort of user comparisons that I was looking for. Do you know what cam is in your 1776? I am a bit concerned about splitting the case since I do my own work (my 71st birthday is in Sept) and if one is not cutting themselves short by sticking with the stock cam, am inclined to go that way.
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