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oldskoolkool

carbs, now down on power =-(

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Lookin forward to seeing what the rolling road has to say, oldskool how much roughly has all this cost you? And have u gone from a 2.0l to a 1.8? If so what was the reason? I'm keen to go down the itb with megajolt(or something similar and a coilpack no distributer route. Tryin to find out as much as possible while saving the pennies.

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Lookin forward to seeing what the rolling road has to say, oldskool how much roughly has all this cost you? And have u gone from a 2.0l to a 1.8? If so what was the reason? I'm keen to go down the itb with megajolt(or something similar and a coilpack no distributer route. Tryin to find out as much as possible while saving the pennies.

 

 

hi mate yeh i cant wait till the rollers either lol! will be good to see how much it dosent make :lol: i went from a 2.0 because the old engine was haggered!, and i had a 1.8 so i thought id play with that!

 

the engine has been gasflowed and schrick cams in it, with mani and lightend flywheel, and obviosly the massive dellorto 45s :D

 

ive spent about a grand on the engine prob a little bit more! wayyyy more that the cars worth lol! are you thinking of bodies or carbs ?? any info you need matey just ask

 

liam

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hi all, in my experience of converting multipoint injection to carb it doesnt work just regulating the flow using the original fuel pump the pump works for a while then burns out trying to pump way to much fuel through to smaller regulater.

 

i all ways run a facet pump but not sure what psi it is. i do this all the time on other model cars when i race them in bangers. im sure the seat ibiza dizzy is the one aswell

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hi all, in my experience of converting multipoint injection to carb it doesnt work just regulating the flow using the original fuel pump the pump works for a while then burns out trying to pump way to much fuel through to smaller regulater.

 

i all ways run a facet pump but not sure what psi it is. i do this all the time on other model cars when i race them in bangers. im sure the seat ibiza dizzy is the one aswell

 

 

Not quite sure you point ? a facet low pressure pump is always needed along with a pressure reg to obtain and keep a steady pressure of 3.2 psi of fuel pressure. using the origianal pump, you will only have to have a high pressure regulator then a low pressure reg to bring down the pressure to the disired pressure, and also the pump will be unstable at these high pressure as the pressure from a standard pump is 70 psi as said earlier in the post.

 

and is a seat dizzy a full dizzy with bob weights and advance/retard on it mate ???

 

liam

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pressure is created by the restriction not the pump, i think stuart is just saying the OM pump won't be recirculating and therefore the pump overworks and fails, could be entirely wrong :grin:

 

the 1.5 seat dizzy does have the vacuum advance weights, discussing with henny on a different thread recently though - these need to be reweighted to suit the kr, dunno who'd be capable of doing that these days

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hi all, some of you might know the problems ive been having and what ive been doing, but heres the low down !

 

basically my old 2.0 ltr went poof so i got a 1.8 with the following mods, port and polished head, four branch manifold, 220 schrick cams, lightened flywheel, so i put this in my car a while back on standard management (motronic) and made a miserable 142 bhp and 113 tourqes! and i had to run the exhaust cam a to retard to make it run anywere decent, ???

 

so anyway i tried everything and still that was the best power ! i carried on like this for a while asking people what is going on and why am i getting terrible power, as people on here always say a 2.0 ltr with kr head and manifold with make 160 easy ?? no matter what i do or spend i dont ever seem to get above 130-40 bhp!

 

up to date i now have a pair of twin dlha45e dellortos slapped on there and i made a whopping 126 bhp with 11 tourques yesturday i tried the cams in every way possible but still got less that stock power, all the engine manigment system has gona bar the ecu, the carbs are set up properly but still no joy! the best i got was 131 with playing with cams and timing !

 

i dont get it would it be to do with the head being gasflowed ?? or is it management ? or is it the lump ??? i dont know any more, im 4k down on this car now in total and have less power than a ford feiesta !!! im getting seriusly pi**ed off

 

i dont know what to try any more i put a set of kr cams in last night and it ran flat as and at that point i went to bed haha !

 

does any one have any ideas anything would be a great help

 

i know there is some clued up people on here could you please be kind enough to share some of you lovely knowlegeness and help a male in distress haha

 

 

 

im getting fed up please help pleeeeeeeeeeeaaaaaaaaaasssssssssssssseeeeeeeeeeeee!1

 

happy monday to you all peace out lol liam

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No worries chap - it's just this way at least people can see the history of what you've done and tried to cure the problem, which only helps you at the end of the day :)

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How was the fueling and timing set up? Was the carb jetting set up while on rolling road as well as truing the distributer while on max power to archive optimum ignition timing,what venturi sizes are you running? what length stack pipes have you got?

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mate i've said what i *think* your problem is on your other thread, the increase from 1.8 to 2ltr by VW was to address stricter emissions regs which would have caused a loss of power to the 1.8... so the fact you've gone from 2ltr to 1.8 whilst keeping the motronic has lost you power straight out the bag - despite all the various mods you have i suspect you are simply fighting against the lambda/ motronic

 

firstly i'd seriously consider swapping back to 2ltr with all your bits attached, i'd then think about standalone management with carbs or otherwise - the latter ain't cheap :(

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Given the lairy spec of the engine you're going to need some proper diagnostic equipment to set that up properly and you're going to need to be able to map the spark appropriately.

 

If you're running OEM spark timing then given how different the motor is to OEM you're going to be waaaay out on the advance curve to accommodate the cams - the whole lot's simply not going to work properly.

 

Do you have any idea what the mixture is doing across the rev-range?

 

Is there a vacuum feed that goes to the ECU? If this isn't connected then it may be that you're not getting the spark advance you need because the ECU doesn't think it's under load at any point - sh*t in, sh*t out.

 

Ads this topic has visited the carbs vs EFI thing, the carb proponents need to answer is how are you going to control the mixture appropriately across the whole rev range (and a 16V loves a wide rev-range). You're running on open feedback loops all the way, so there is little to no control, just a bunch of fixed values that have been defined on a certain set of variables under certain conditions.

 

You *can* set up carbs once, but the requirements for winter temperature running will be substantially different to summer running - there's no way for the carbs to accommodate that.

 

You just have to look at the number of considered variables pulled into a modern EFi unit to understand how many things are considered to generate optimal running within the defined parameters of the built engine. Unfortunately if you mod the engine substantially you take the EFi outside of the parameters it has been set up to operate in. This is when you get running issues.

 

To get those carbs running properly you need a gas analyser (wide-band lambda would help)and a spark unit where you can control the advance, preferably hooked up to a knock-sensing box. Once you have these feedback loops you can control the mixture by manually adjusting the carbs and enable a basic self-tune of the spark, so it advances to the point that knock *just* starts to come on and then pulls the advance back.

 

With those controls you *might* get it running properly, but to get it optimal (and capable of running a cat) you need to toss the carbs away and replace with well set up throttlebodies and proper EFi.

 

If you *really* need help with this I know a guy in Ross-on-Wye who might be able to assist.

 

Just my thoughts on the matter.

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Iv been looking at some zx9r bike carbs but im unsure to buy or not

Its a full set up got the butcherd mani and samcos all hooked up to the carbs and a small fuel pump the only thing it needs is a filter on the open ends

Im just wanting to know how much of a pain its all goin to b to fit ! Or not ??

Iv got an old school guy near me whos supposed to be really good at setting them up even by sound and ear lol

Also uses a rolling road to set up everything

How much should i be paying for all this kinda stuff does anyone have any answers??

Cheers im not ace at the engine side of things its not the i cant do it more the i dont know how

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