jimbona2
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posted on 27/3/08 at 10:09 AM |
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throttle bodies or carburetors?!!?!?!?
okay, this feels like the biggest question of my life, which way do I go, carbs or throttle bodies?
I know throttle bodies are more expensive but offer better maintenance and ease of installation?
carbs being the opposite, cheaper, harder to install.
whats the general opinion as its keeping me up at night!
cheers!
[Edited on 27/3/08 by jimbona2]
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Mr Whippy
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posted on 27/3/08 at 10:12 AM |
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How good are you with computers?
I like carbs as their familiar and I can fix them but admit they're no match for an injection system.
Fame is when your old car is plastered all over the internet
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jimbona2
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posted on 27/3/08 at 10:15 AM |
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im a web developer so not bad
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Paul TigerB6
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posted on 27/3/08 at 10:17 AM |
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I'd go for a set of bike throttle bodies myself on the Zetec with a Megasquirt. Weber / Dellorto carbs were a pain to keep in tune so if going
carbs it would be the bike carbs route for me, but why not go the whole hog and have the even better TB's
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jimbona2
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posted on 27/3/08 at 10:20 AM |
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whats TB? !! thanks!
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Paul TigerB6
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posted on 27/3/08 at 10:23 AM |
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quote: Originally posted by jimbona2
whats TB? !! thanks!
Throttle Boddies
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02GF74
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posted on 27/3/08 at 10:23 AM |
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depends on age of engine for SVA emissions test. if post 1995 yoiu need TB and cat.
pre will pass on carbs.
if ^^^ does not apply, then carbs are much cheaper and simpler.
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whitestu
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posted on 27/3/08 at 10:38 AM |
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I've gone for carbs due to ease and cost.
No need to plumb in a fuel return etc. Carbs and pump cost £40. Manifold [if it works properly] cost another £20.
Stu
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jimbona2
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posted on 27/3/08 at 10:40 AM |
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do TBs give better performance?
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Mr Whippy
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posted on 27/3/08 at 10:50 AM |
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quote: Originally posted by jimbona2
do TBs give better performance?
Simply…yes, plus the mega squirt thing can be programmed to match that individual engine exactly, something which is not possible to do with carbs.
Even be best duel choke Webber setup is inferior for many reasons.
Not that it's stopping me putting duel carbs on my Falcon, why? cos they look awesome
[Edited on 27/3/08 by Mr Whippy]
Fame is when your old car is plastered all over the internet
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Schrodinger
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posted on 27/3/08 at 10:58 AM |
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Define better performance?
If you mean more hp or torque then probably not but if you mean useable across the rev range and possibly better fuel ecconomy then you most likely
will get that if they are set up correctly for your engine.
Keith
Aviemore
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jimbona2
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posted on 27/3/08 at 11:46 AM |
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good question, i was initially thinking about the acceleration to 60mph but thats probably a silly thing to think off...?
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Paul TigerB6
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posted on 27/3/08 at 12:14 PM |
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As mentioned above you will find the driveability improved over carbs. Having driven zetecs with both Dellorto's (my own old Tiger S6), Webers,
and bike carbs, I found the bike carbs gave improved driveability over the Webers / Dellorto's. Bike TB's should be a big step up again in
terms of driveability.
Peak power figures look great on paper, but in the real world you drive on the torque. The ability to really have full control over the fuel mapping
should see you gain much improved torque curves and maybe a little extra power right through the rev range. For this reason alone you should end up
with a slightly quicker car which is smoother to drive.
On the downside, start-up costs are higher as mentioned with the extra fuel return, possibly a swirl pot, dearer megasquirt system etc. Also a full
rolling road session is likely to be dearer but you will benefit from lower ongoing costs. Do the sums i'd say and see what your preference is.
I'd still have to say you should be able to get running on bike TB's considerably cheaper than paying WebCON for a weber carbs / ignition
system for which Tiger are about the cheapest.
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BenB
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posted on 27/3/08 at 01:40 PM |
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It's simple really
There's nothing wrong with a well set-up pair (or more!) of carbs. However, setting it up can be tricky and often gains in one rpm area will be
at the loss of power in other parts of the rev range.
With throttle bodies everything is adjustable and you can iron out any flat areas. It's also easier to adjust and therefore you'll be more
inclined to squeeze out the last few Bhp...
At the end of the day badly set-up TBs will be just as bad as badly set-up carbs!! With carbs you have to muck around with jets, needles and choke
sizes (and you're always going to run into compromises). With TBs you just adjust the laptop
Nothing wrong with carbs- but I'm still converting to TBs...
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jimbona2
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posted on 27/3/08 at 02:14 PM |
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how much work is involved in bolting the throttle body option together?
any photos of this additional fuel return thingy?
thanks,
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Paul TigerB6
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posted on 27/3/08 at 02:22 PM |
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Have you got the Tiger injection tank or the standard one at all Jim?? Depending on which will depend on how much work is involved. Standard tank
could be used to feed a seperate swirl pot in the engine bay via low pressure pump and then having a high pressure pump in the engine bay to feed the
TB's. Injection tank will involve fitting a second pipe to the rear and then using a suitable pump to feed the whole system.
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jimbona2
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posted on 27/3/08 at 02:28 PM |
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the fuel tank is from tiger.
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Paul TigerB6
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posted on 27/3/08 at 02:45 PM |
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They do both an injection tank and one designed for carbs. The injection one has a second outlet on the end for the fuel return plus some internal
mods i believe. I would assume therefore that you have the single outlet one for carbs.
I think the best option in this case would be to fit a low pressure pump at the rear and run this to a swirl pot (like
this) or similar. The 3 outlets on the side are for low pressure feed, high pressure outlet and high pressure return. There's
then a breather on top.
From this swirl pot you feed the throttle bodies via a high pressure pump to the fuel rail and then believe you will need a pressure regulator after
the rail before returning to the swirl pot. You will probably want a filter in both low pressure and high pressure lines before the fuel pump also.
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coozer
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posted on 27/3/08 at 04:10 PM |
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Depends how old the donor engine is, pre 95 will be fine with carbs, but the newer you go the tighter the emissions are the more easier it will get
with bodies.
Saying that if I was doing it again I would use throttle bodies with megajolt. Just for the techno factor
1972 V8 Jago
1980 Z750
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Paul TigerB6
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posted on 27/3/08 at 04:37 PM |
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quote: Originally posted by coozer
Saying that if I was doing it again I would use throttle bodies with megajolt. Just for the techno factor
Errr you mean MegaSquirt, just for the fueling factor
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mark chandler
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posted on 27/3/08 at 04:45 PM |
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No need for a return if you run a swirl pot up front, then the efi is closed circuit but you do need two fuel pumps.
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Jenko
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posted on 27/3/08 at 04:59 PM |
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quote: Originally posted by mark chandler
No need for a return if you run a swirl pot up front, then the efi is closed circuit but you do need two fuel pumps.
My swirl pot has an overflow outlet on the top which has to be routed back to the fuel tank.........So, even if the swirl pot is at the front does it
not still need some return back to the fuel tank?......The only time I could see this not being an issue is if you have a one way fuel rail set up and
the pump regulates the pressure........
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big_wasa
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posted on 27/3/08 at 05:23 PM |
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So what happened to the mondeo efi ?
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coozer
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posted on 27/3/08 at 05:31 PM |
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quote: Originally posted by Paul TigerB6
quote: Originally posted by coozer
Saying that if I was doing it again I would use throttle bodies with megajolt. Just for the techno factor
Errr you mean MegaSquirt, just for the fueling factor
Sorry my mistake I did indeed mean Megasquirt. It's good for fuelling and spark and believe can determine the boost as well for a turbo engine
I'm building
Steve
1972 V8 Jago
1980 Z750
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Paul TigerB6
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posted on 27/3/08 at 05:39 PM |
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quote: Originally posted by Jenko
My swirl pot has an overflow outlet on the top which has to be routed back to the fuel tank.........So, even if the swirl pot is at the front does it
not still need some return back to the fuel tank?......The only time I could see this not being an issue is if you have a one way fuel rail set up and
the pump regulates the pressure........
I have wondered about the top outlet myself as they seem to be marked as either a return or breather (as per
here) depending on how you run the system i guess??
Is what Jenko says above the reason it can be used as either???
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