my mate rash has got himself some bike carbs for his pinto and while listening to
a conversation he had at harrogate
with a guy running bike carbs , its got me
thinking ??????????
has anyone run them on an xe 16v red top
i like a bit of a challenge and its seems not insamountable to make a manifold
any comments , idea,s please
what carbs to use ???????
if this works i will have a set of 40,s on a xe manifold for sale

If you can afford it, go with bike throttle bodies.

Same principal but you'll also need megaquirt (at the least) and GSX-R (more commonly) throttle bodies.

The alternative is R1 carbs and a cav dizzy with the advance curve modified, although you may already have all this for your 40's?

You'd probably break even with selling your 40's/manifold and getting www.boggbros.co.uk to make up the manifold and supply suitable carbs/filter.

May only cost £150-200 more to go the throttle body route, but its just slightly more complex. Definately better economy and power though.

A few people on http://www.migweb.co.uk/forums/ and on here are running both setups, just can't remember their names.

mnr had bike carbs on an ecotec demonstrator a while back.


I have also seen a few bike carb pics on xe's on migweb.

Ned.

the throttle body route is more than i want to spend
i would like to think i could fabricate my own manifold
the bit about
"cav dizzy with the advance curve modified "
tell me more about this please

The standard XE distributor contains only a cam phase sensor for the sequential injection, not very useful to run a stand alone igntion system. There are three ways to get around this:

1) Buy an aftermarket ignition ECU that uses the standard 60-2 timing wheel built into the XE's crank.

2) Fix a 36-1 wheel to the crank pulley and use a Megajolt ignition system

3) Replace the XE distributor with one from a early 2.0L 8v carburettored Cavalier that contains a mechanical advance system and electronic igntion module. The advance curve will be incorrect, so this will need fixing.

You might want to nick the Cavaliers steel sump while you are at it!

You can go for the bike carbs but as pointed out, you have to step back to the dark ages of clockwork ignition timing, which will pretty much destroy the advantages of using the bike carbs to start with comapred to the std vauxhall injection!!!!

You really need mapped ignition to actually make any use of the carbs, in which case you need to buy megajolt anyway at least, and then injection costs nothing extra really!!!

Bike throttle bodies are as cheap if not cheaper than carbs, need the same manifold, it just makes no sense to me using the carbs when you have to sort the ignition anyway!

so basicaly you say the carbs wont run with the cav dissy
i dont really understand the megajolt
ecu system enough to go that route.
it may be an antiquated system useing a dissy but thats my chosen path , im not looking to go racing , the car will just be for fun

quote:

---

Originally posted by nige
so basicaly you say the carbs wont run with the cav dissy

---

carbs will "run" with the cav dizzy but you'd be better off with the std vauxhall/bosch injection/igniton if you are doing that

H & H ignitions do a dizzy ignition set up Nige , that are suited to your application,

Whether or not it's deemed to be "dark ages" technology - My Pinto on points run great and I also intend to use the cav dizzy on my XE , with webber 45's,
Many have used this path before!

I think what nsdev etc are saying is that it should work fine, but don't expect great figures from the engine on a standard cav dizzy, with a modified one it will be better but injection still offers better power/torque curves, fuel effeciency and more responsiveness from the engine.

Ned.

ps doing it on a budget i'd personally go for bike throttle bodies (which are no more expensive than bike carbs) and get either a megasquirt if you want cheapness and diy or for a bit extra (not a lot by the time you've bought/built a ms system) an emerald ecu that you could probably get a reasonable map for. You can argue that to get the best out of any system, carbs or tb's you should get the car rolling roaded.

[Edited on 16/8/06 by ned]

as i said early doors i dont want to and cant justify the expence of an ecu and throttle bodies , i know that is the best way forward in regards to power and
finite tunning , but i dont understand it enough .
i would be much happier with carb s for now
i have a cav dissy it was just a thought
about bike carbs as this seems to be popular at the mo
ive looked at the h&h site , very interesting, welcome all the comments and dont diss any ,because we all cant have the same opinions, this site would be very boring if we all fitted the same gear

OPTION IS AS FOLLOWS:

Cut down the standard alloy injection manifold to leave oval stumps. Depending on what bike carbs you go for you'll then have to get the correct diameter rubber tubing and jubilee clip them to the manifold. Due to the oval nature of the cut down manifold you'll have to get it undersized so it will be a tight fit. Carb Float bowls need to sit horizontal to the ground btw.


Pic Courtesy of Cidersurfer

Grab a vauxhall dizzy & coil module from a mk2 shape non ecu ign cavalier - They come in a few different shapes, my coil & module looks more like a coil pack than a coil -billys unit is more of a traditional coil style.









You'll have to cut the end down on the main dizzy shaft as it's too long as standard to fit into the end of the cam on the xe. There are 2 different types of protruding drive shapes on the dizzy's - you want the one the same as in the picture :



Wiring is your simple Ignition feed, earth and rev counter. Spark plug leads can be a hassle as you need ones that fit the old style dizzy cap and also have enough reach for the recessed spark plugs in the xe head.

I read that adjusting the bob weight spring rates to alter the ignition curve made little or no difference so I'm not sure if it's worthy the hassle to have it modded.

Get a professional to set up and sort the bike carbs.


Job's a good un.

I replaced this setup on billy's with a MBE 906 (Caterham XE map) ECU + Wasted Spark Coilpack setup (Throttle position/Water Temp etc) - It ran ok but he's since swapped it back to the traditional dizzy and reports that it run's the same if not slightly improved.

So in all honesty it's each to their own



Next weeks instalment :

THE OPTION



[Edited on 16/8/06 by Mr G]

quote:

---

Originally posted by Mr G
I read that adjusting the bob weight spring rates to alter the ignition curve made little or no difference so I'm not sure if it's worthy the hassle to have it modded.

---

three cheers for that man
big up mr " g "
just the down to earth simple laymans terms i was looking for
ive got a dissy and a coil
also the stock manifold , so just need the carbs

see where you are coming from, no problem.

I used to think that carbs were simple and injection complex, until I started to use an aftermarket injection system.

Yes its not cheap, but done secondhand its not too bad.

The big plus is that it is so much more simple than carbs!!!!!!

What you don't want to do, if you are new to injection, is get into the megasquirt stuff on tinternet!!! It put me off straight away, yet I am fine mapping my MBE stuff!!

With all the aftermarket race type systems you basicaly stick in number sofr injector opening times and ignition advance. much simpler than peeing around with holes in bits of metal in carbs!!

I have a set of bike carbs if you want them, zx10 racing carbs, in good nick, and i only live 20 mins from you.
I bought of some one who was going to put them on an xe for racing , but decided to pack it up.




[img]zx10[/img]

[Edited on 18/8/06 by roadrunner]

quote:

---

Originally posted by MikeRJ
If that was really the case then we could fit a universal advance curve to every engine!

---

In case this is of interest.

BRAND NEW dissy for 20XE on carbs that has been recurved to suit an XE by H&H Ignition Solutions. £80 ono.

Linky

[Edited on 22/8/06 by the_fbi]