Ob
28 posts
Joined: 03/12/2004 21:54:05
Location: United Kingdom (Excluding channel Islands)
Throttle by pass valve
Ive had a similar problem on my Mpi engine, the idle bypass valve was dirty and causing it to stick. Not sure if its the same on the Spi engine but worth a check anyway.
Posted: Jan 30, 2005 08:30 AM
Matt1977
27 posts
Joined: 05/01/2005 19:21:43
Replacing throttle body on an MPi mini / fitting a stage 3 kit
Hello all, Ive seen that its possible to buy a replacement throttle body for MPi minis. Its made of metal rather than plastic and increases the diameter of the trottle body by 4mm. The advert claims improved torque and acceleration across the whole rev range of ca. 10%. Can anyone explain to me how this is possible, what the effects would be on fuel economy etc? Are there any dangers in doing this? Im also interested in fitting a stage 3 kit to the same car. Does anyone know if this will poison my catalytic converter or cause any other problems?
Posted: Feb 11, 2005 11:52 AM
pickme
672 posts
Joined: 08/09/2004 23:10:14
Location: Chippenham United Kingdom (Excluding channel Islands)
Throttle Body. This replacement (assuming you mean the SU one) is better because: a) its bigger (you can get standard size) so this can improve air flow if you have a suitably modified inlet manifold. This means more fuel/air can get into the cylinders. Strickly speaking, it doesnt ADD power, just removes a bottle neck in the air-in-exhaust-out process which can result in a power increase. b) It opens fully rather than the 75% maximum from the standard. Also improving full throttle air flow. c) its metal, so is less prone to cracking which can cause air leaks and cause the throttle butterfly to jam open. I doubt that the side effects would be that great. The ECU will not let the fuel/air mixture get to the point that it will damage the CAT. Stage 3 Kit. Depends what you mean by a stage 3 kit. This tends to mean different things to different people. If you buy one designed for an MPi Mini, then it should work fine or they wouldnt sell many.
Posted: Feb 11, 2005 03:53 PM
geckoman
1 posts
Joined: 05/08/2005 16:55:56
Engine Cuts Out When Throttle Is fully open
I have a mini mayfair from 1986 it has been having problems it would occasionally misfire when i bought it especially when throttle was open a little and you would have to put your foot to the floor to stop it as it could get quite severe. Now it cuts out everytime you open the throttle more than a little. It seems to rev normally if you gradually open the throttle but if it is suddenly opened it just cuts out. ANY IDEAS??? Thanks! Simon
Posted: Aug 05, 2005 05:17 PM
jimbob 1984
6 posts
Joined: 21/09/2004 12:36:32
Location: Figino Switzerland
Body throttle..
Hi I was wondering if the 52mm throttle body that you sell is also for Spi edition minis?! Ive read that this fuel system can produce a power gain up to 10% and that is more reeliable than the original plastic ones.. Thank you!! James
Posted: Aug 10, 2005 05:12 PM
SPi throttle body.
I have a new one for sale if your interested. You could also try Minisport (the only place Ive found online who actually have one) who are selling them for £350 at discount (ouch). Im selling mine for £250.
Posted: Aug 13, 2005 12:10 PM
Jan
37 posts
Joined: 14/10/2004 16:34:54
Location: Oslo Norway
spi inlet and throttle body
Woods and picket has a kit that is giving appx 10 % more according to them. Price is still £350 but I believe this is on exchange only. So you have to take into consideration freight of old kits from Swiss to England. jan
Posted: Aug 22, 2005 09:06 PM
Neil
Joined: 11/02/2005 07:20:41
Location: Chichester United Kingdom (Excluding channel Islands)
MPI Throttle Pot
The throttle pot is used across many of the Rover MEMS equiped cars. In the past I have obtained them from Scrap Yards. Remember we are talking about the potentiometer itself not the complete throttle body. Also It may be worth talking to Burlen Services as they fit a new TP to the metal throttle bodies they supply. However do check that the throttle cable is not stopping the throttle plate returning correctly to its mechanical stop. It only needs to be held off by a few thou to cause problems. The throttle pot itself engages on to the throttle shaft by means of a D section flat on the shaft. Slack there can be the problem. If you loosen the the TP mounting screws there may be enough slack in the TP holes to rotate/bias the TP slightly and recover the lost motion. Good luck, Neil
Posted: Nov 20, 2005 09:28 AM
Problem with Burlen 52mm throttle body on my twin point Cooper
Hello all, I recently fitted a 52mm Burlen throttle body to my twin point Mini Cooper and ive had some problems with it namely: 1) The idle speed is high (ca.1300 RPM at idle). 2) The spring on the arm connected to the throttle cable doesnt go back to a hard stop. 3) In traffic when i push down the clutch pedal the engine revs up to about 4,500 RPM and wont go back to normal idle without holding the clutch on the bite-point until the clutch starts smoking! 4) The range of my car has reduced by 30%(probably the high idle) 5) When i change up a gear the revs increase despite me not putting any pressure on the throttle pedal !!! Has anyone had a similar experience or an idea of whats wrong / how to fix it? Every month in MM and MW i see cars with this little blighter fitted and no-one seems to have problems - in fact everyone seems to see an improvement with MpG etc! Have i just got a faulty one or are some of the things listed above a standard improvement over the original part??? Thanks Matt
Posted: Mar 31, 2006 12:18 PM
Andy
20 posts
Joined: 30/11/2004 11:44:55
Location: huddersfield United Kingdom (Excluding channel Islands)
Hi, i have one myself. does the throttle butterfly close fully when your foot is of the peddal? if not the the ecu will not recognise an idle throttle position but you can adjust it with the throttle stop screw on the side, this is what i had to do as mine was miles from closing properly when i got it out the box! hope this helps.
Posted: Apr 01, 2006 12:58 PM
J. Astrop
31 posts
Joined: 31/10/2004 19:55:38
Rev's after foot off throttle
I have a quick question about something which i don'tr know the term for, so i'll explain...
When I take my foot off the throttle, the rev's die down and slowly get back to idle as they should. It seems to be rather slow on my 1275cc MG Metro Engine,
A) What is the term for this?
B) Is there any way of increasing this response?
Posted: Jun 04, 2006 08:12 PM
John
1948 posts
Joined: 28/05/2006 16:49:46
Location: cambridge United Kingdom (Excluding channel Islands)
increase responce shud think some wd40 on linkages. dunno if u mean 'over run' can be due to leaking valve seats if it doesnt have hardened valve seats might be this, although would need to hear it to tell.
Posted: Jun 04, 2006 09:21 PM
I think it's called 'throttle response' or at least that can improve it.
If you hear a ferrari revving the rev's go up and immediately back down to idle, real quick (not that i'm expecting that sort of performance).
The warmer the enging gets the slower the rev's get back to idle after i've taken my foor off the throttle.
Any ideas?
Posted: Jun 06, 2006 02:22 PM
Tim
1850 posts
Joined: 18/10/2004 09:40:59
Location: Bournemouth United Kingdom (Excluding channel Islands)
Sounds like a carb problem of some sort - has it got oil in the dashpot? Also check that it's bolted up tight to the manifold, and that the manifold is tight on the cylinder head - air leaks can create all sorts of problems. Is the vacuum advance pipe or the servo pipe (if fitted) leaking?
Posted: Jun 06, 2006 02:41 PM
I think everythings running ok, and it's all connected up properly.
This isn't a problem as such, just something i'd like to improve.
Posted: Jun 06, 2006 03:16 PM
Roy
261 posts
Joined: 19/09/2005 19:34:20
Location: huntingdon United Kingdom (Excluding channel Islands)
This could become a problem as it sounds like a worn carb to me. tho' it could also be a sticky throttle cable, or as has already been mentioned, dry linkage.
Posted: Jun 06, 2006 09:09 PM
C. Barron
332 posts
Joined: 04/05/2006 21:28:31
Location: Mid Calder United Kingdom (Excluding channel Islands)
Also, Is the vacuum advance mechanism in the dizzy, if it has one, well lubricated and free to move ?
Posted: Jun 06, 2006 09:12 PM
chrispy61
51 posts
Joined: 08/12/2005 22:27:39
Location: Torquay United Kingdom (Excluding channel Islands)
i no what you mean, my m8s mini revs up alot faster and then back to idle think its becoz the bottem end is lightend and he has a lightned and balanced flywheel. hope this helps
Posted: Jun 07, 2006 06:20 PM
MattBumble
3 posts
Joined: 11/02/2007 22:03:08
52mm Burlen Throttle Body
Hello
I recently fitted a fancy new 52mm throttle body by Burlen.
The problem is, I get a hissing sound when the throttle is in a particular position, just as I slightly accelerate past "maintaining speed at 40mph" kinda position.
Almost like when you turn on a tap and in a certain position its all noisy and wooshy, know what I mean?
Well anyway, this isnt normal is it? If not, how can I find out what the problem is?
Also, what results have other ppl had after fitting one? Ive not really noticed much, apart from a deeper noise and a very slight loss of power at the top end, which Im hoping is just ECU confusion. Although its been fitted for over a week now, surely it would have smoothed out by now?
Cheers guys, I hope you can help
Posted: Feb 11, 2007 10:13 PM
T. Perks
57 posts
Joined: 19/11/2006 09:21:16
Location: Wotton under Edge United Kingdom (Excluding channel Islands)
Sounds very much like you have an ait leak some where, having not fitted one myself, do they have a gasket or an o ring under them check all is lined up right try the old squirt some wd40 around the joints trick and see if its drawn into the engine.
Posted: Feb 12, 2007 11:28 AM