carbs

Anyone running weber 45s? and does n e 1 know what u need and whats involved i fitment ect

The carbs, and suitable inlet mani, throttle linkage, low pressure fuel reg, mk1 gti dizzy, aparently optional but personaly if your gona do it, do it right
What other mods will you be doing?
You cant just wack on the carbs and expect big gains, you will need atleast some decent cams and exhaust to take advantage of the extra air and fuel going in

Gary

ive got fast road cams and a full janspeed exhaust with 4 2 1 manifold, do u think that would b alrite. its things like the throttle linkage i would get stuck on sourceing i think. 2 b honest im not 100% on how they work would i still have standard fuel rail fitted? i was thinking bout buying a head thats been port polished aswell could just do with a desent head really then i (with the help of a friend) could rebuild the bottom end. whats the crack with port polishing does it help at all if ur not turbo. and i dont suppose u would b interested in makeing me a manifold next year if i send u the carbs cuz i know u know what ur talking about and every other bit u av made me has been super high quality. my friend seems to think u can just chop down a standard inlet and pipe on the carbs but i wouldnt of thought so myself. cheers for the post m8 i can always relie on u to sort me out.

A good set of carburettors will cost nearly as much as a set of propper throttle bodies and will never be as good.
Webers and Dellortos which are the common side draft carburettors available are notoriously susceptible to age. old ones corrode, erode, warp etc so going new is in the long run the best practice, even going old youll probably want to rebuild them with gaskets etc. then like throttlebodies they will need tuning to suit the car, this is as costly as throttle bodies and can probably be done by ever decreasing number of tuners.
no point doing it if your going to dodge a manifold, a propper manifold will mount the carburettors at the right angle relative to the head. As with throttle bodies the inlet tract should be as uniform, step and obstruction free as possible matching the throats tot he manifold and manifold to the carburettors would be recommended but not essential to just get running.
An inlet port should not be polished, it should be many grades shy of polished to help mix the air and fuel, the exhaust should be super polished to minimise friction of gasses on the way out. It is more important on Normally aspirated engines than turbo to have this work done, of course if its done on a turbo all the better.
Carburettors use much lower fuel pressure than injection so this needs adjusting. throttle linkages are easily available new and or second hand and east to install.
so thats the fuel dealt wirth you will need spark. Rumour has it the Mk1 distributor has vacum advance so is the one to get as mentioned above, this allows spark timing to suit rev range, which the ecu would do in injection but needs to be analog in a carburettored situation.

Anyway thats enough for now.

GTP

Hi,

In order to run carbs you will need to do followings.
change fuel pump(carbs need 3-4psi)
Don't use Weber try get hold of Dellortos, they are better developed so it won't go out of tune 2 days later.
Or get R1 bike carbs, they fit and forget.
You will need to have mk1 Dizzy(if you can find 1 about £100), they are indeed mechanical with a vacume advance. If you run a mk2 dizzy, you will be running with get you home mode. I know it still works but not as it should.
Ask Gary nicely to make you an inlet manifold. You can cut up std manifold but you want keep it just in case you need to go back to std.

Ask around, there may be people with spares you will need.... like me!

Cheers
Atchi

well thats defo taught me alot i didnt know, thanx for sharing ur knowledge its much appreciated. i just love the way carbs sound and ive been told they add a ton of torque which is what im afta and ive just been looking on ebay and theres sum 1 selling r1 carbs on a gti manifold so i thought they would have been tryed and tested so i had a look at just a set of r1 carbs and u can buy a set for about 130 and with the help of sum 1 with the knowledge to make me a manifold i thought it mite be quite cheap aswell. is there n e other carbs that would b cheap and work well on the gti?

carbs make no more or less torque than anything else its to do with tuning secondly but physical parameters first. Longer Intake tract length creates torque
Carbs do sound good but throttle bodies do too.
GTP

Please make sure the angle of carbs mounted.
R1 is mounted 75 degrees(down drought). I have mounted mine on 52-ish degrees.
Some of Honda CBR1000 carbs are side drought so straight manifold will do.
I think you want 36 to 40mm size so 600cc to 1000cc will do. Most of bike carbs are easy to modify to fit 84mm part like G13B.

You could always ask Boggs brothers and scare yourself off with how much it will cost you in the end.
I think if you are lucky, it will cost you £600 before RR session.

Solid state fuel pump £80, dizzy £100, carbs £100, manifold £100, fuel pressure reg £60, air filter with plenum chamber £200.... .

Cheers
Atchi

Hi,

I have a spare mk1 dizzy.. yes they are rare but I have them.
I have an inlet manifold flange data which I can get it laser cut.

You will need a lower pressure fuel pump your injection pump will be too powerful to pressure regulator to control.
You can those bits as well as a plenum chamber from Demon Tweaks or ebay like I did.

I bought a Lotus air box off ebay.
I made back plate CAd and got it cut by laser in 3mm sheet Aluminium. It fit very good. I will be making adaptor plate for K+N filter for later but I'm building so many other things at the moment.

http://www.teamswift.net/gallery/image_page.php?album_id=471&image_id=7855http://www.teamswift.net/gallery/image_page.php?album_id=471&image_id=7854

I hope these link above works!

Cheers
Atchi

ive managed to raise the funds to buy the carbs and manifold thats on ebay so thats sorted im sure its the carbs dominator had for sale ages sgo but i missed the end of the auction. but im well interested in the mark 1 dizzy how much would u want for it posted to pl5 1qz i wont av the cash for a couple of weeks tho so would u be willing to keep hold of it for a while? do u really need the air box when my friend had webbers on his pug he just had like socks over the trumpet looking things, sorry im not too sure what the proper name for them is

I wanted to run carbs but its a pain in the ass

yes you can get away with socks, but as soon as you oil them they become restrictive. to do it properly you want a tuned airbox
carbs are easy almost easier than efi if you know what you are doing and can get jets and tubes etc to tune it, but just as costly
all carbs need jetting to suit your engine, the same dangers as efi of damage with incorrectly tuned carburettors.
Cheers
GTP

i was going to fit em with a m8 then take them to jre racing a place in saltash near where i live and get them set up i wouldnt have a clue how to set them up to b honest.

does n e 1 know where i can get the throttle linkage ive been told u av to make a custom 1 or u can buy a uni 1 and cut to fit.