Bike carb set up on 2001 vtr what do I need?

29th November 2010, 10:00

Thinking of getting a set of these I know I will need manifold and the carbs what else do i need wiring? Pipework? Etc

29th November 2010, 10:13

fuel rail, throttle cable, sensors, different injectors i beleive, also socks, theres allot more, there is a thread on it somewhere let me find it for you.

29th November 2010, 10:15

Throttle-Body Setup *Section taken from GMC Motorsport*

Instead of going down the boost route, you could also go down the N/A route and still get pretty big power. This will come in the form of throttle-bodies.

Why fit multiple throttle bodies?

The purpose is to allow unrestricted flow of air to the cylinders, which is often a problem with standard inlet manifolds, plenum chambers when searching for maximum bhp. Having said this too many people jump to the conclusion that this what is holding their car back and want a throttle body kit. There is no point fiting throttle bodies on standard engine or on one that is only mildly tuned, as unless you have a high lift cam, head work, performance manifold and exhaust system, etc your engine will not be able to use the extra capacity of air you are throwing at it.

Sure it will go better but the money for a throttle body kit would give more power if you used it for the above mentioned parts, the only big benefit would be the fantastic sound that only throttle bodies give. It must be remebered when going for throttle bodies, the vast amount of other parts needed to fit them, the parts usually needed besides the throttle bodies themselfs are, inlet manifold, fuel rail, adaptors for trumpets, trumpets, air box, filter, throttle switch, linkage etc. For a rough guide most throttle body kits cost over £1000 plus fitting, plus you will need some form of programable management and the cost of programing time on the dyno.
Most relativley highly tuned engines do need throttle bodies, an example is the British Touring Car Championship, they are forced to use 1 single 64 mm throttle body and they still get over 280 bhp. I am noy trying to put anyone off the idea of multiple throttle bodies, just trying to make you aware that this is not be all and end all of serious tuning.

Another example is the full race Saxo VTS engine GMC Motorsport built for a racing series in Taiwan, this engine made 150 bhp at the wheels, OK a lot of money was spent to get this and would have been a lot cheaper to get this power by not doing certian things and using mulitple throttle bodies. The reason I mention this is that many people are worried about insurance and the fact the insurance engineer will be able to see the engine has been mwage tuned if he sees throttle bodies on it, whereas you can stiil have an enigne that looks reasonalbly standard from the outside and give good power on the standard throttle body.

So what is a throttle body set up worth over the standard single unit. Assuming the engine has been well sorted first, 15 bhp is usually the extra gained, on a basically standard engine, probably about 5 to 7 bhp. These comments are based on saxo engines, some engines have terrible inlet manifolds and plenum chambers, the Vauxhall Corsa 16 valve being one where far more could be expected.

Asuming you have decided to go for a mulitple throttle body set up, which throttle body do you specify. The best we have seen are the weber and Jenvey units and recently we have been favouring Jenvey more, as they do a far greater range of sizes and fitting applications, particularly short bodied units, which are a must when fitting to a front wheel drive car that has the induction system pointing to the bulkhead.

The reason I mention this is that just fitting a throttle body kit on any car, is only going to work well if certain rules are followed. The three main things you must achieve are an inlet length (from cylinder head to the end of the trumpets) of at least 15 inches, as if this is not achieved, all the power will be at very high revs and a reduction in low speed power.

Secondly, it is no good having a system that makes the trumpets nearer than 2 inches away from the bulkhead as this will restrict air flow and finally it is no good sucking hot air from the back of the engine. So unless you can fit an unrestricted air box that draws air from the front of the car you are wasting your time. If you were to fit a throttle body kit that does not achieve all these functions it is doubtful it will be of much if any advantage over the single one it replaces.

29th November 2010, 10:15

I just took that from the "Read me: before starting a new thread on engine etc"

its a sticky at top of the page mate.

29th November 2010, 10:16

Why would I need injectors? There carbs not throttle bodies

29th November 2010, 10:17

Oh shit, mybad thought it was throttle bodies

Well, would be allot more hard work to get carbs to work on a saxo - the cost of them would be far more than if you were do to throttle bodies, hence why no one has done carbs for saxo's

29th November 2010, 10:18

Your quoting stuff about throttle bodies mate please read my thread carefully I said carbs not throttle bodies

29th November 2010, 10:21

I can get the carbs off a cbr600 for £60 and a manifold made to suit for £100 just wasnt sure what to do about wiring like removing tps and injection

29th November 2010, 10:23

Quote:

Originally Posted by C18VTR

Oh shit, mybad thought it was throttle bodies

Well, would be allot more hard work to get carbs to work on a saxo - the cost of them would be far more than if you were do to throttle bodies, hence why no one has done carbs for saxo's

Quote:

Originally Posted by Rallypvc

Your quoting stuff about throttle bodies mate please read my thread carefully I said carbs not throttle bodies

Ye I think he gathered that mate.

29th November 2010, 10:26

Quote:

Originally Posted by SAM-S44MDS-

Ye I think he gathered that mate.

Yeah he posted a second or so before me lol

29th November 2010, 10:29

http://www.saxperience.com/forum/sea...archid=4561553

you will find all the threads started on this forum about carb's with allot of answers to them (note; these are old threads) with allot of information from a few members in one or two of the threads, and from what ive read, you cannot remap the ECU with carbs to set the fueling right

29th November 2010, 10:44

Quote:

Originally Posted by C18VTR

http://www.saxperience.com/forum/sea...archid=4561553

you will find all the threads started on this forum about carb's with allot of answers to them (note; these are old threads) with allot of information from a few members in one or two of the threads, and from what ive read, you cannot remap the ECU with carbs to set the fueling right

Thanks for that mate had a look through the threads seems a little complex but I like a challenge might be pos if I can get hold of a megasquirt piggy bak cheap enough think that will open up the fueling parameters enough ( I hope )

29th November 2010, 10:45

im trying to remember the name of a piggyback ECU that was popular back in the day, it could be called KMS? not too sure, but can pick one up for about £80 or so

29th November 2010, 10:50

Sound good I'll google it

29th November 2010, 10:54

Doesn't come up with much they seem a little too dated I'll have a quick look at megasquirt

29th November 2010, 11:09

Seems to be what I need is a megasquirt with the v3 software which allows for the wiring to the injectors to be left disconnected and all I need to do is ignore the furling tables when setting it up and basically use it as an ignition timer and that should do the job it also help to remove the tps from the system as well which is good

1st December 2010, 13:38

i was thinking of doing this to mine too, my friend has a 106 quicksilver hes putting a vtr engine (blacktop) in with a set of r1 carbs so im waiting to see what his is like and hopefully copy his set up with a different manifold to suit the silvertop vtr engine.

1st December 2010, 13:42

this sounds complicated :s :L

1st December 2010, 19:04

Fuck carbs, it's a backwards step. Use bike bodies if you really want it. Efi is miles better than a carb setup IMO

2nd December 2010, 23:04

fuck carbs off all they do is throw fuel into the engine whilst injection sprays exactly the right amount of fuel/air mixture so u get a perfect stoichiometric (i think thats how u spell it) ratio. Have u ever revved a bike really hard from tickover they just bog up and nearly cut out + if u buy carbs and manage to fit them you will have to buy different jets change ur needle posistion and find the right balancing for your carbs which will probs cost a good few hours labour even with someone who knows what there doin and then the next day when the weather changes cos lets face it we live in england and the weather changes like katie price's husbands the car that ran like runny shit off a hot shovel now runs like a tin of beens cos the air will either be thicker or thinner. Its a bad idea thats why bikes are fuel injected now haha

2nd December 2010, 23:05

i spelt beans wrong haha !