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Twin 40 manifold
leon51274 - 26/2/10 at 09:50 AM

Morning

Hoping for some help please. Went to put my twin dellorto dhla 40's on my 1600 crossflow yesterday and they don't fit! I replaced the dizzy cap with a side entry one and the manifold is still catching it. The manifold is very short at 3" so i'm thinking that this my problem as they originally came off a lotus twin cam, before i go splashing more cash can someone confirm to me that a 4.25" long manifold will sort my problem?

Many thanks
Leon


mcerd1 - 26/2/10 at 10:04 AM

have you considered electronic ignition? (e.g. megajolt)

that way you wouldn't need a dizzy at all and you can tune a progamable electronic one better than any dizzzy


02GF74 - 26/2/10 at 10:49 AM

there are at least 4 types of manifold.

short and long and come in two angles (I think one is horizontal else is less steep but don't quite me on that)

generally the ones that are angled are for the 1300 block to raise carbs to clear the dizzy.

I have 2 spare angled manifolds, short one that was used on 1600 block with side entry cap and long one that is identical to the one on my 1300 block - I had Ford dizzy with normal cap but with small lead covers that allow the leads to bent round to clear the manifold.

so if you have 1600 block, then the angled one ought to be fine as it was fine on my 1300 block.

If you are using Bosch dizzy, you are gonna struggle more since that is taller than the Ford one.


leon51274 - 26/2/10 at 11:45 AM

ok, cheers men.

Well the manifold is a short angled one and i'm using a bosch electronic ignition so it sounds like i'm buggered, How much will a megajolt system set me back?


mcerd1 - 26/2/10 at 12:10 PM

£90'ish for a built MJ unit

+£20'ish for a trigger wheel

+£30-50 for the donor bits -> EDIS4, coilpack and a VR crank sensor - all with plugs + wires
(can be very cheap if you get them from the scrayard)

+ a TPS sensor for the carbs if you want a 3D map (or a MAP sensor, but its harder to set this up on multiple carbs)

so it should be cheaper than an aftermarket dizzy


I managed to get all of that for £130
inc. the whole loom from the donor which managed to get out whitout cutting any wires (my donor was a k reg 1.3 escort btw)
(not including a TPS - my bike carbs had one already)

I got the MJ itself as a built unit from Paulf on here - might be worth sending him a PM to see if he still does them


this link has loads of info on how to do it: linky
(links a little old now, but still gives you the idea)


[Edited on 26/2/10 by mcerd1]


norfolkluego - 26/2/10 at 12:34 PM

Two things.
1. You can get a complete Crossflow Megajolt kit from Trigger Wheels that will have everything you need but will cost the thick end of £300. Sourced separately you should be able to knock £150 off it.

2. We've just done an engine change from a Crossflow with twin DHLA 40s and had no problems mounting the carbs. the manifold was angled upwards, I'll find a picture of it when I get home

[Edited on 26/2/10 by norfolkluego]


britishtrident - 26/2/10 at 12:40 PM

Lotus twincam's didn't have inlet manifolds.


leon51274 - 26/2/10 at 12:46 PM

could it be that the bosch dizzy is just too big? Are lucas ones shorter?


Fatgadget - 26/2/10 at 01:05 PM

quote:
Originally posted by britishtrident
Lotus twincam's didn't have inlet manifolds.


I think what he is saying is the Dellortos came off a twink.

Dellortos as far as I remember have accelerator pump underneath. It would tally with the installation issues. making them more likely to foul the dizzy on a xflow than Webers


leon51274 - 26/2/10 at 01:12 PM

quote:
Originally posted by norfolkluego
Two things.
1. You can get a complete Crossflow Megajolt kit from Trigger Wheels that will have everything you need but will cost the thick end of £300. Sourced separately you should be able to knock £150 off it.

2. We've just done an engine change from a Crossflow with twin DHLA 40s and had no problems mounting the carbs. the manifold was angled upwards, I'll find a picture of it when I get home

[Edited on 26/2/10 by norfolkluego]





A pic would be good, cheers mate


mcerd1 - 26/2/10 at 01:19 PM

one more thing - if you went for MJ or similar you'll need something to blank the dizzy hole

there was a thread a wee while ago which I can't find - but this is the sort of plug you'd need

X-Flow dizzy plug
X-Flow dizzy plug


02GF74 - 26/2/10 at 01:43 PM

^^^^ is correct, the lotus twin cam had the "manifold" as part of the cast head.

yes, the Bosch is taller than the Ford unit.

dellortos have the fuel pump levers below but as I said earlier, I had pair of 40s on a 1300 crossflow with enough clearance so nothing got fouled albeit on the long manifold.

I have a Bosh as Ford distritbutor spare too.


Fatgadget - 26/2/10 at 01:43 PM

quote:
Originally posted by mcerd1
one more thing - if you went for MJ or similar you'll need something to blank the dizzy hole

there was a thread a wee while ago which I can't find - but this is the sort of plug you'd need


X-Flow dizzy plug
X-Flow dizzy plug



A locost solution would just be a blanked off old dizzy no?

[Edited on 26/2/10 by Fatgadget]


02GF74 - 26/2/10 at 01:47 PM

a plug is very sophisiticated - I reckon you could drill one or two holes and bolt down a plate over a gasket - there already is one hole for the distributor clamp.


pajsh - 26/2/10 at 02:08 PM

Deffo go MJ. More reliable and adjustable.

I cut the top off the dizzy, made a cap for it and mounted the coil pack on top.

Pinto 2.0 - 2
Pinto 2.0 - 2


02GF74 - 26/2/10 at 02:34 PM

^^^ yeah, but that is not a crossflow but a pinto - doesn't it use the distributor to turn the oil pump round hence you cannot remove it?

Pretty sure someone on here did that and found here was no oil pressure


mcerd1 - 26/2/10 at 02:41 PM

I've actually got a cut down dizzy for my own pinto, but as above it wouldn't be much good without it


but the plug is actually quite locost - if you've got access to a lathe
even if you don't it'll only cost a few £ to get made
(I recon the one in the pic cost me £6 for the material and postage)


but pajsh's solution is also good, if you've got the space:

quote:
Originally posted by pajsh
I cut the top off the dizzy, made a cap for it and mounted the coil pack on top.


btw - there are 2 types of coilpack - the early ones are the ones you'll find in the same donor as the EDIS4 etc..
and the later ones are on the newer zetec's and so on
only significant difference between them is the plug's on the coilpack end - if you get the early ones then you can get std. plug leads off the shelf with the right ends on them
(if you use a later coil pack all the std. leads have the big rubber boots on the spark plug end for the 16v engines)


[Edited on 26/2/10 by mcerd1]


pajsh - 26/2/10 at 02:59 PM

quote:
Originally posted by 02GF74
^^^ yeah, but that is not a crossflow but a pinto - doesn't it use the distributor to turn the oil pump round hence you cannot remove it?

Pretty sure someone on here did that and found here was no oil pressure


True enough it is still needed for the oil pump. The idea still applies though.


leon51274 - 26/2/10 at 04:14 PM

Not sure i've quite got the cash for the megajolt nor the savvy to get the bits from a scrapy.

Suppose its down to if a longer manifold will sort the job and/or different dizzy!


mcerd1 - 26/2/10 at 04:56 PM

have you just got a standard dizzy at the moment or has the vacume advance been taken off ?

[Edited on 26/2/10 by mcerd1]


leon51274 - 26/2/10 at 05:08 PM

quote:
Originally posted by mcerd1
have you just got a standard dizzy at the moment or has the vacume advance been taken off ?

[Edited on 26/2/10 by mcerd1]



Its a standard bosch electronic setup with vac advance which i was just going to block off. I've just had another look and the flange nearest the carb is catching on the top ht plug so i'm thinking a longer manifold will sort it.


mcerd1 - 26/2/10 at 06:04 PM

its your choice, but you might want to keep MJ in mind for future upgrades - with a 3D map it should give you a few extra MPG and a better throttle responce than the dizzy


norfolkluego - 26/2/10 at 10:37 PM

Pics as promised Rescued attachment e3.jpg
Rescued attachment e3.jpg


norfolkluego - 26/2/10 at 10:39 PM

Not a huge amount of clearance and the manifold need to be angled up Rescued attachment e1.jpg
Rescued attachment e1.jpg


norfolkluego - 26/2/10 at 10:47 PM

Looking at the pics I would say 02GF74
is right, if the manifold was any shorter the fuel pump levers would foul the dizzy cap, answer would seem to be longer manifold.

[Edited on 26/2/10 by norfolkluego]


leon51274 - 27/2/10 at 09:59 AM

quote:
Originally posted by norfolkluego
Looking at the pics I would say 02GF74
is right, if the manifold was any shorter the fuel pump levers would foul the dizzy cap, answer would seem to be longer manifold.

[Edited on 26/2/10 by norfolkluego]




Thanks for that, much appreciated.

It looks like your using a lucas dizzy? Looks a lot shorter than mine.

What length is the manifold?


leon51274 - 27/2/10 at 10:00 AM

quote:
Originally posted by norfolkluego
Not a huge amount of clearance and the manifold need to be angled up



Thanks for that, much appreciated.

It looks like your using a lucas dizzy? Looks a lot shorter than mine.

What length is the manifold?


norfolkluego - 27/2/10 at 12:45 PM





Thanks for that, much appreciated.

It looks like your using a lucas dizzy? Looks a lot shorter than mine.

What length is the manifold? [/quote
Haven't got it anymore to measure it but I'm guessing about 4 inches plus flange