heres the problem. when you hold 1/4 throttle (and a tiny bit more) the engine feels like its sputtering definetly can feel it like its missfiring (it doesnt seem major but slight vibration can be felt). all the igntion components are fine but will check again i mean the dizzy cap, rotor, plugs and wires are well under 10,000kms old.

any ideas i dont think the TPS could do stuff like this, oh yeh im on advanced timming but run 98 octane fuel always.

what i think it could be;

fuel related problem / fuel starvation?
timming gone out of place (well timing chains in these cars are ***t so it could have gone few more deg advanced).

thing is it only happens with slow and steady acceleration (or its more noticable), with foot to the floor etc you dont notice it at all. think its time for a new fuel filter its about 2yrs old i guess.

Same symptoms happened to me when one of my leads died.
If you say uve already checked that then.. i dunno


Wouldnt be fuel filter causing that much disturbance only 2 years old, unless u got a real big bloackage.

sounds like a flat spot in the carbi to me. if you hold the throttle in the exact spot does it keep doing it indefinatly? if u drive thru it with more throttle does it go away?

Cant be the TPS, coz u dont have one. :badgrin:

Just for laughs tho, do a compression test.

carbys do have a TPS which is used select an approriate gear for the auto tranny, it serves no other function other than that in a carby model.

ill re-check my leads tommorow but i doubt it.

"sounds like a flat spot in the carbi to me. if you hold the throttle in the exact spot does it keep doing it indefinatly? if u drive thru it with more throttle does it go away?"

that is spot on. its nothing huge but its noticable.

"sounds like a flat spot in the carbi to me. if you hold the throttle in the exact spot does it keep doing it indefinatly? if u drive thru it with more throttle does it go away?"

that is spot on. its nothing huge but its noticable.
eeep, them carbi's are uneconimcal to replace/rebuild.. might be webber time.. good cos u will get some go out of it, bad cos its expencive

humm looks like it, i know this carb has been rebuilt (well ages ago) and it cost a fair bit. addin the webber will make fuel economy worse no doubt. i guess doin a webber conversion wont be that bad just doin something for an adaptor plate is tricky.

humm looks like it, i know this carb has been rebuilt (well ages ago) and it cost a fair bit. addin the webber will make fuel economy worse no doubt. i guess doin a webber conversion wont be that bad just doin something for an adaptor plate is tricky.

Brendan will let you know about fuel econ, i dont think it will be any different once the carbi is tuned properly. Idle mixture is rich if you just plonk the webber onto the astron aswell as cruise and full throttle mixture, bad for power and econ. I changed the secondary jet in brendans when i rebuilt it then he changed the primary aswell not too long ago. That helped with econ and added some power. Idle is still lopey but he is just waiting for jets then i guess we'll have a play with my AF meter to see how we go
:cool:

Idle is still lopey but he is just waiting for jets then i guess we'll have a play with my AF meter to see how we go
:cool:

not that youd notice it in an auto :P (i cant wait to get my webber)

not that youd notice it in an auto :P (i cant wait to get my webber)
not as much, but its the fuel econ, plugs, exhaust, pistons, head, valve which dont like running rich. fouling them isn't the best of ideas.

carbys do have a TPS which is used select an approriate gear for the auto tranny, it serves no other function other than that in a carby model.

ill re-check my leads tommorow but i doubt it.

"sounds like a flat spot in the carbi to me. if you hold the throttle in the exact spot does it keep doing it indefinatly? if u drive thru it with more throttle does it go away?"

that is spot on. its nothing huge but its noticable.


ohh whoops... auto. My bad. Get that baby a manual box.

the only thing i can think of causin the flat spot is the secondary jet is slightly clogged. but looks like i kno wat ill be doin this w/e.

grab a 34 ADM weber carb off an xf
grab a rebuilt kit (major or minor) from repco
spend 4hrs cleanin and rebuildin

i dont think the stock jets will work well with the 2.6, even after a tune http://www.redlineweber.com/html/Tech/carburetor_set_up_and_lean_best_.htm

the only thing i can think of causin the flat spot is the secondary jet is slightly clogged. but looks like i kno wat ill be doin this w/e.

grab a 34 ADM weber carb off an xf
grab a rebuilt kit (major or minor) from repco
spend 4hrs cleanin and rebuildin

i dont think the stock jets will work well with the 2.6, even after a tune http://www.redlineweber.com/html/Tech/carburetor_set_up_and_lean_best_.htm

PM brendan, i forget what we put in his car. also find yuorself a 40 and a 45 idle jet and have a play around mixing with the 40/45 45/40 45/50 50/45 etc etc, you will get a 50/55 with it aswell as a 155 and a 210 or there abouts. they are all much to large and rob power if not changed

jets in my car as follows:

idle - 40 (was 50)
- 45 (was 55)
primary fuel - 127 (was 135)
secondary fuel - 160 (was 220)
primary air - 160 i THINK
secondary air - 160 i THINK.

dont quote me on the air jets, cause i cant quite remember.

this is just to get it to stop the overfuelling. we havent put on AF meter as of yet to find out the best jets to give the right mixture. but, it does feel abit quicker definately with the new primary and secondary fuel jets in it. i dont have the 40/45 idle jets in yet cause they havent arrived to the shop (weber have gone broke). so on launch it bogs down pretty bad, but once on throttle it hammers.

another thing i noticed in ur post u referred to the XF weber as a 34... its a 36/36. magna carb was a 32/35. another thing to look at is how ur throttle cable will attach to the new weber carb. i STILL havent sorted mine out and it does cause some problems. mainly the slack in it, causing the car to jolt wen i hit secondaries. i just say i hit MIVEC :bowrofl:

fuel economy is surprisingly not much worse than the standard magna carb. aslong as that right foot isnt on the floor all the time that is.

and wen u just have a tiny bit of throttle on, and increase it very slightly, u can begin to hear the carb suck. goddam it sounds cool

i guess the weber is good enuff for a turbo setup too. i take it you are goin to go down the turbo path, and i doubt you are goin to go drawthru (carb before turbo).

the weber would need a bit of work to get it to work blow thru it will crush the float, fuelin will be a bit of an issue too. but the plus side runnin blow thru is u can hav an intercooler and blow off valve :D i hav a t28 lyin around

out of all my options goin EFI prob gonna cost me more.

fuel economy is surprisingly not much worse than the standard magna carb. aslong as that right foot isnt on the floor all the time that is.

and wen u just have a tiny bit of throttle on, and increase it very slightly, u can begin to hear the carb suck. goddam it sounds cool[/QUOTE]

I totally agree with you, the weber sounds great under slight acceleration
and then when you put the boot in it makes this great growl.

im having trouble with my accelerator cable too, it feels sticky when u try and make small changes. i made this small clip the other day of the sound of the weber under full throttle.Magna Webber (http://members.westnet.com.au/mccormack/magna_weber.asf) :D

so on launch it bogs down pretty bad, but once on throttle it hammers.

Thats your accel pump and cable problems i reckon. idle air is say for example 1cc/s where are 1/10th throttle is around 100cc/s so you can see idle mixtue/fueling will not really effect on throttle econ or smoothness.

TM-terror nice. another one with no bonnet sound detening :D . yeh i removed mine but found the part on the bonnet just under where the exhaust manifold to be wayyyyyy to hot and was scared it would wreck the paint, so i trimed mine to a tiny rectangle on the bonnet which goes over the exhaust manifold and threw the rest away. perfect now.

the stock carb with an aftermarket air filter sounds insane notice the turning heads esp at 5000rpm + :badgrin:


yeh looks like ill grab a weber this w/e and spend free time givin it a clean and rebuild and see how it runs with stock jets etc after a tune.

TM-terror nice. another one with no bonnet sound detening :D . yeh i removed mine but found the part on the bonnet just under where the exhaust manifold to be wayyyyyy to hot and was scared it would wreck the paint, so i trimed mine to a tiny rectangle on the bonnet which goes over the exhaust manifold and threw the rest away. perfect now.

yes you will find that thing under the bonnet its not for sound detening its a heat stoper, they put them in many cars after they found the heat from the motor caused the bonnet paint to bubble and ***up cos of the heat

yes you will find that thing under the bonnet its not for sound detening its a heat stoper, they put them in many cars after they found the heat from the motor caused the bonnet paint to bubble and ***up cos of the heat

i found that either way the bonnet was getting quite hot, about as hot as cup of coffee after a run. my paint hasnt been affected yet though. But that might be because i removed the splash guard next to the radiator, so its got a constant supply of air going through the engine bay.

actually im suprised it didnt do damage when i killed my last engine, i ran it for too long with a leaky radiator, trying to limp it home from dwellingup. i reached the top of the engine temp guage a couple of times. when i got up to kwinana and stoped to drop my mate off the engine was so cooked the oil and leads had started smoking . You should have seen the state of it when i took the engine out : ) the oil looked more like maple syrup and tar, plus one of the lifters had melted at the top. and 2 of the Caps that hold the cam in place had sheared. how the hell it was still running?

i found that either way the bonnet was getting quite hot, about as hot as cup of coffee after a run. my paint hasnt been affected yet though. But that might be because i removed the splash guard next to the radiator, so its got a constant supply of air going through the engine bay.

actually im suprised it didnt do damage when i killed my last engine, i ran it for too long with a leaky radiator, trying to limp it home from dwellingup. i reached the top of the engine temp guage a couple of times. when i got up to kwinana and stoped to drop my mate off the engine was so cooked the oil and leads had started smoking . You should have seen the state of it when i took the engine out : ) the oil looked more like maple syrup and tar, plus one of the lifters had melted at the top. and 2 of the Caps that hold the cam in place had sheared. how the hell it was still running?

Mine was running for nearly 7 minutes with no oil pump. When we took the motor apart, 5 months later, we could still turn it by hand easily, and technically return it to service as it sat. Decided against it, as I want to exceed the half million mark before the next repowering.

yeh i would say mine gets about the same heat of a hot coffee cup. ive seen a fair few cars with no heat/sound protector for example the s15 200sx.