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bigger carbs

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bigger carbs

hey ppl i wanna get a bit more power out of my 1.8 and was thinking maybe bike carbs.
how easy is this or is there a better solution. thanks

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bike carbs are easy to do as long as you can get a minifold 300 pound then 100 for carbs



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and you'll get no power increase.

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the 1 problem i have is im not sure i have the room behind my engine for all that. surely u get some power increase if not o well i love the sound of carbs haha and i got a cabby so dont wanna crusie at 150 jus wanna get to 80 quick and enjoy the sound with the roof down

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novocaine said

and you'll get no power increase.

But they make a whooshing sound thats worth £400 isnt it? :)

~Madferret



Mk1 1457cc 5door GX '83

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im guessin ur takin the p*** but im not after silly power i jus want a bit more exceleration and i think i will get that from some carbs and yes i love the sound they make.:):) i did think about jus droppin a 1.8 20vt in it but want to keep it old school and the engin i have in it has jus been re build so cant c the point in swappin engines. surely u must get some power increase otherwise ppl wouldnt do it.
has anyone got any more info plz

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the carbs arn't the restriction. you will still have to jet them to get the same air/fuel ratio.

yes mr ferret is being funny. its because this has been asked so many times now that it's sort of seen as a joke.

more power can be gained by sorting the basics.
timing, air filter, etc.
or by flowing the head which is a little more effort.

people who do it to get power tend to be doing it to a valver. becuase it's easier to fit than injection.
it's become an internet myth that it will give you more power. and you get the usual qoutes of figures normally based on lots of mods made not just the carbs.

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thanks for the info well i wasnt jus intending on slappin a set of carbs on it and b done with it if im gonna do it i will do it the right way. was just wondering wat carbs r best to go for thanks anyway

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if you really want to do it. go for a set of mikuni's from a suzuki gsxr 750. jets can be purchased seperatly if you google for them.
they do fit behind an 8v head but the air inlet is a bit awkward.
the mikuni carbs have a vacuum take off which can be used to control the distributer.
bog brothers can do the manifold for you but it's pricey.

be prepared to spend time changing jets, setting needle heights etc. to get it running right. then balancing the buggers every few months to keep it running well. if you are going to do it consider electronic ignition if it's not already installed.

as a personal beleif i dont see the point i think bike carbs are made for bikes. but each to there own hay fella.

Dave

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thanks well i was jus thinkin bike carbs as i got told it was cheaper but if i can stick car carbs on for the same price then ofcourse im gonna go with the carbs made 4 cars lol

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Dude.

A Carb conversion is only a part of getting more from an engine, bike carbs will deliver some power increase for sure, but limited. The reason being they will deliver better air flow and volume which in turns means more fuel and results in power and torque. You also get better response. The stock manifold is an awful design, based on reliability over performance.

Having done a carb conversion I can say my cabrio is much better for it!!! I'm running a single 40 dellorto through a lynx M150 inlet manifold, a proper old school set up.

There is a bit more to consider with the carb conversion, not just the which carb/manifold conversion.

Fuel delivery will be an issue with either carb engines or injection engines. The carb engine uses a mechanical fuel pump which will not deliver enough fuel and the injection uses en electric pump which delivers too much pressure. Dellorto carbs need about 2 - 2.5 psi pressure, and a high flow rate.
To get round this I have an electronic fuel pump fitted (mine was a carb model) running into a sytec pressure regulator. Facet or huco do suitable pumps. Injection will need a reduction regulator. The carb model will also need the heater relay from the old manifold heating system throwing away and a nice new injection pump relay fitting in it's place (extra wires needed).

The carb model also has a water heated manifold, when changing to an aftermarket manifold there is a hole left in the head, this will need something doing with it. I have blanked mine off along with the coresponding inlet to the metal water pipe. No overheating problems or water leaks so far. I have used the same method as guy I bought the conversion from.

Finally you'll need to hook up some sort of throttle cable linkage. Conventional car carbs are easy as there are kits available off the shelf, with bike carbs you'll need to be a bit more creative. I will be replacing the linkage on my dellorto with a new single cable setup using a modified OEM cable as the linkage I have at present is an odd mixture of original and aftermarket. There are two types of car linkage, single or twin cable. the latter needs work on both the bulkhead and the throttle cable to work.

The other problem with carb conversions is lack of space at the back of the engine bay, I think I have about 30mm between the ram pipes and the bulk head. This means filters can an issue.

Cost wise, if you use all new:

Carbs £500-650, Manifold £160, linkage £60, fuel pump/regulator £100 other bits and bobs £50-100

Second hand will be loads cheaper

Hope this helps you in decision. :D

Projekt Frustration :

 White 1991 Clipper. Lowered over polished zender rims, Single 40 dellorto on lynx manifold, kent cam, full stainless 'zorst / manifold, powerflex bushed and braced. Not the fastest car, but sounds super nice!

Still going after 12 years… never said it was a quick fix! Time is not my friend.

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Read up on carbs and you'll understand the principles more, if you drive the car at full whack everywhere (at night) you might find you get better performance, but presuming you live in england and drive during the day, you'll not see anything worthwhile.

You can get similar performance from jetting the carbs, or on an old carb just re-building the carb.

~Madferret



Mk1 1457cc 5door GX '83

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thanks for the help ppl think i mite jus get the bodywork and inside sorted first then decide wat to do thanks again everyone :)

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Personally if you've got a good working car I wouldnt mess with it :)

~Madferret



Mk1 1457cc 5door GX '83

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Like I said, my cabrio is much better to drive now than It was with the excuse for a carb originally fitted. I don't drive it full wack everywhere, it just gets used like any other car. The only slight problem is the lack of a choke, but you soon learn how to deal with it  8)

As for not messing with cars, I think each to their own on that one. I bought the cabrio with every intention to modify it along with restoring it as we go. Some of the mods have enhanced the car and others have gone some way to removing it's floors (brakes for one).

I had to change the carb on mine as the original one decided to stick open and cause the engine to idle at 3500 rpm. This made it scary to drive! I picked up the Dellorto for a very reasonable price and in my opinion Its far better than either the pierburg or the weber replacement. :mrgreen:

Projekt Frustration :

 White 1991 Clipper. Lowered over polished zender rims, Single 40 dellorto on lynx manifold, kent cam, full stainless 'zorst / manifold, powerflex bushed and braced. Not the fastest car, but sounds super nice!

Still going after 12 years… never said it was a quick fix! Time is not my friend.

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I dont mean don't modify it. I mean don't mess with the bits that wont improve it's value overall hard to explain what I mean on that I guess.  :D

~Madferret



Mk1 1457cc 5door GX '83

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thanks for everyones different replys lol
not sure wat to do no mite jus say fook it and chuck a 20v turbo in it as my mate mite b changin his engine soon and said i could have his old engine lol how easy is this and ruff cost of doin it thanks

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that all depends on the choice of management system for one.
you'll also need modified mounts, some kind of intercooler, custom exhaust……
I don't think you can just chuck a 20v turbo in
i'm sure there will be more on this in the modifications bit of the forum.

Projekt Frustration :

 White 1991 Clipper. Lowered over polished zender rims, Single 40 dellorto on lynx manifold, kent cam, full stainless 'zorst / manifold, powerflex bushed and braced. Not the fastest car, but sounds super nice!

Still going after 12 years… never said it was a quick fix! Time is not my friend.

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Mind If I just throw a post in here while your on about carbs and I don't know alot about them but is there any dellorto carbs that directly fit onto a 1.5 like the webers do, as the 36 Tlp's don't seem to be very much in abundance as the others :/

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Not to my knowledge (maybe wrong!).

Dellorto Carbs are either side draught or down draught, depending on the model. I have DHLA (side mount), DRLA are the otherway, usually found on VW aircooled motors.

The problem is that unlike a weber they are not OEM replacements (unless you have an old Alpha) and need a special manifold. I don't know if the fitment is the same for a 1.5 and a 1.8 engine???

The manifold I have is a Lynx M150. I have only ever seen mine. I have found ones for ford pinto engines, but sadly non for VW. You could try google or similar! I know a guy in South Africa does manifolds, but I don't know if they'd fit or even if He ships world wide.

Hope this helps….

 8)

Projekt Frustration :

 White 1991 Clipper. Lowered over polished zender rims, Single 40 dellorto on lynx manifold, kent cam, full stainless 'zorst / manifold, powerflex bushed and braced. Not the fastest car, but sounds super nice!

Still going after 12 years… never said it was a quick fix! Time is not my friend.
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