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Old 27th December 2007, 23:13   #1
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Need help and advice for carburettor change in Premier Padmini

First, my wishes to all the forum members for the new year.
Now coming to business, I have a 1986 year Premier Padmini. We've had it for 20 years now and I just love it but can't really take it out every day because it performs lousily. I thought a change of carburettor can do the magic so I want you guys to help me out in this. I would like to fit a weber DCOE carburettor. I want to know if it will fit my car, will it do the job else what other parts I need to put in, in order to make it perform to its highest level and also where I can I find them, It would be good if I can find it Mumbai as it would be easy for me to get it from there. The weber carburettor is just a choice, ideas for any other good carburettors are also welcome. Mileage is not a problem but performance is vital.
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Old 28th December 2007, 00:38   #2
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DCOE is not for a stock engine. If you have a race cam, higher compression, and a full exhaust system, then yes. Otherwise, you will pull out your hair in frustration because in 90% of the cases, it will not run right and will give you ridiculous fuel economy (4 or 5 km/l is low enough to be a problem, right?) without making even one horsepower extra.

I say stick with a new or rebuilt solex (the older style w/ accelerator pump) or at most, get a maruti 1000 twin choke carb. The latter will perform the best on the street. You won't be disappointed.

EDIT: I just read your post and you say you want the best possible street performance. In that case, install what's known as a rally camshaft, shave the head by 1 mm & get it ported by someone who knows what he's doing. Due care needs to be paid to piston-to-valve clearances. Top it off with proper LCB headers (go to the old school guys for this, they will know what it is), and twin solex carbs (stock type). If you are hell bent on getting webers, get the downdraft 32 DGV installed on a proper manifold instead of a DCOE and call it a day.

Last edited by ananthkamath : 28th December 2007 at 00:49.
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Old 28th December 2007, 01:14   #3
 
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WHOA WHOA WHOA...wait a second...where the hell are you going to find a stage 1 rally cam in this day and age...(i have one )..and if you do find one please inform me i wanna buy one more..and secondly-if you get your hands on a new solex..BUY IT..they are very difficult to find..and if you find one that is not leaking(second hand) buy that too and keep it..also the zen/800 carbs(mikuni) will fit on the intake manifold but a bracket will have to be fabricated or you will have to find one of the 70 odd manifolds which were designed for mikuni (i have 2 )...go to my picture gallery..the red fiat has a mikuni conversion on it already..
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Old 28th December 2007, 06:39   #4
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i dont know where he will find one......that's left to him. Having had access to every conceivable Fiat 1100 race/rally cam ever made available (and some not ), I tend to think everyone does too.

IMHO, even the stock 16/56 cam on the Fiat is not bad timing-wise. So if finding a cam is an issue, use the existing one and pay attention to the rest of the package.

Either way, a DCOE is a bad, bad idea on the street.
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Old 28th December 2007, 19:18   #5
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Hello to you Rajnikhil - please read carefully - DO NOT - repeat - DO NOT open your engine if it is running fine. As far as the carburettor is concerned, my son Cyrus has covered most of what I would have told you. The best thing to do is to get a good or new Mikuni double barrel carburettor of the Maruti Zen or a 118NE and fit it either by replacing the intake manifold or by using an adaptor. Be careful, you will have to provide for a fuel return line otherwise fuel pressure increase will not allow the carburettor to work properly. You will also have to changeover to a cable operated accelerator control system.

Further, I am copying, editing and pasting some standard procedures which I had sent sometime back to 1100D in Kolkata. You will find this information useful.

My name is Behram Dhabhar.

I am delighted to recieve your communication and I will be more than happy to help you. Before I start, let me give you some background about me and my passion.

My passion is automobiles. My hobby is also automobiles. Incidentally, my hobby is my job also.

FIATS are my passion. I now own 5 FIATS, a 1959 model, a fully restored 1964 model, a fully restored 1988 model, a 1994 model in use everyday and a unique 1996 model LEFT HAND DRIVE. With this background, let me start.

I suggest that if you can E mail me some more photographs of the car including the engine compartment etc, I will be able to recieve comprehensive information and reply to you on exactly what to do to set things right. I am giving below, some standard procedures which you can follow to make your car run much better than it runs now.

Engine tuning process:

If the engine is generally working fine, do not disturb the carburettor. New carburettors are just not available even if you are willing to pay for them. As far as the ignition system is concerned, use the following data - if the distributor is made by Lucas TVS, replace the contact breaker, the condenser, the insulator, the rotor, the distributor cap and the spark plug wires. The dwell angle is 60 degrees and the ignition timing is 10 degrees before top dead centre (TDC). Set the valve clearances to 0.2 mm (8 thou) for inlet valves and 0.25 mm (10 thou) for exhaust valves with the engine warmed up and idling. Replace spark plugs. Use BOSCH SUPER plugs with projecting tips for superior performance. Ensure that the exhaust system does not lead to excessive backpressure. Use the original construction muffler. If not available, please tell me, I am trying to get a vendor in Mumbai to manufacture a small lot to correct specifications, which we can all take a couple of pieces each.

Please accept my best regards,

Behram Dhabhar
My mobile number is - 09820709513 - please give me your mobile number also

Last edited by Mpower : 6th January 2008 at 20:54.
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Old 6th January 2008, 15:27   #6
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Need help and advice for carburettor change in Premier padmini

Thank you all and specially Mr.Behram Dhabhar. I am very happy to know that there are still people out there who are really fond of Fiat's. I would also like to thank you for showing interest in my problem. I will hopefully start the restoration of my car (or should I say modify a little) soon. It all depends on how soon I get a job (I am just finishing my engineering). So Mr.Behram Dhabhar I request you not to forget me as I'll surely call you when ever I start this project. I'll have your cell number stored with me. And hey I stay in Hyderabad, just for your info.
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Old 4th December 2009, 17:43   #7
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Sir,

I am Mehul H K, Tirupur dist in Tamil Nadu. I am a proud owner of 1996 model Premier Padmini S1, LPG, AC.

I have problem with the thermostat switch of my car, it doesnt work properly. I changed it with Maruti 800 one but it starts the fan after the temperature crosses half mark in speedo meter, so please suggest me any perfect thermostat switch for my S1.

I also replaced the water pump but of no use, the M800 switch fails to work after some 100 or more Kms.

My mechanics says the S1 car is having this thermostat problem and I need to change the thermostat valve, which he doesnt know were it could be in my car.

Plse help.

Thanking You

Mehul H K
M-+919443330289.
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Old 9th December 2009, 22:14   #8
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Sir, I want to know whether is there any extra earthing wire that connects from engine to chasis in Padmini S1, because recently my car engine was removed and re-installed after that the car lighting have some poer problem.

Battery acid power and alternator are fine. My friend told me that there is a extra wire for earthing that the mechanic might havent fixed so problem with lights.

I have four halgen lights other than the head lights in my car is it the route cause of the problem?
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Old 9th January 2010, 21:23   #9
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Quote:
Originally Posted by Mehul1100 View Post
Sir, I want to know whether is there any extra earthing wire that connects from engine to chasis in Padmini S1, because recently my car engine was removed and re-installed after that the car lighting have some poer problem.

Battery acid power and alternator are fine. My friend told me that there is a extra wire for earthing that the mechanic might havent fixed so problem with lights.

I have four halgen lights other than the head lights in my car is it the route cause of the problem?
Hello Mehul. Your friend is right. the wire he explaied is there. The one end of it is connected to gearbox flange and other to chassis. To verify, take a wire and connect between car body and engine body, and check whether you face the problem..
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Old 9th January 2010, 21:50   #10
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Quote:
Originally Posted by rajnikhil View Post
First, my wishes to all the forum members for the new year.
Now coming to business, I have a 1986 year Premier Padmini. We've had it for 20 years now and I just love it but can't really take it out every day because it performs lousily. I thought a change of carburettor can do the magic so I want you guys to help me out in this. Mileage is not a problem but performance is vital.
You can retrofit an old Mikuni twin barrel carb of the M800 with minor mods - the mount of the stock Solex is like a rhombus,while the mikuni's is squarish - you need to fabricate an adapter so that this can be fixed.Also,a return line to the fuel Tank would need to be laid.

The accelerator rod arrangement in the Padmini would need a modification to run a cable to the Mikuni
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Old 9th January 2010, 22:18   #11
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Quote:
Originally Posted by Mehul1100 View Post
Sir,


I have problem with the thermostat switch of my car, it doesnt work properly. I changed it with Maruti 800 one but it starts the fan after the temperature crosses half mark in speedo meter, so please suggest me any perfect thermostat switch for my S1.

I also replaced the water pump but of no use, the M800 switch fails to work after some 100 or more Kms.

My mechanics says the S1 car is having this thermostat problem and I need to change the thermostat valve, which he doesnt know were it could be in my car.

Plse help.

Thanking You

Mehul H K
M-+919443330289.
Dear Mehul- There is no thermostat valve in a S1 as the car was designed to run on water and not coolant. There is a thermostat switch, which is located on the bottom portion of the radiator. Its like a tail to the radiator. The function it provides is that on a given temp. it sends a signal to start the electric radiator fan.

Regarding the water pump, firstly, there is no connection of the water pump with the thermo. switch, the thermostat switch can fail in even a day or not even in years, cannot say, depends on the quality. Buy a switch which has a carton stating for Premier Padmini S1, hard to find but will be lucky if you find one. Had last seen a PMP make switch, see if it works for you.

I too have used a M800 switch as i went to ask for a thermo. switch and the shopkeeper gave me a M800 switch, saying that "Yeh Chalega'.

Regarding the M800 switch, the engine difference is evident,
800cc, 3 cylinders
Premier Padmini 1100cc, 4 cylinders.

However it can be used as the actuation temp.(as per testing) for fan for S1 is 87 degrees and M800 is 90 degrees, so difference is 3 degrees. The other way to tackle, if you feel, the problem of overheating/late actuation which was told to me by Behram Dhabhar, is to add a switch in the passenger area to start the fan manually. See the needle rising or off the mark, simply start the fan and switch it off as the temp. recedes.


Any other problem with your S1, let me know. Have told this and will repeat, let my sleepless nights be of some use to others.

Last edited by kavesh55 : 9th January 2010 at 22:25. Reason: added words
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Old 9th January 2010, 22:40   #12
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Quote:
Originally Posted by kavesh55 View Post

Any other problem with your S1, let me know. Have told this and will repeat, let my sleepless nights be of some use to others.
That is extremely nice of you I must say- great approach
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Old 11th January 2010, 02:29   #13
 
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Quote:
Originally Posted by vigsom View Post
You can retrofit an old Mikuni twin barrel carb of the M800 with minor mods - the mount of the stock Solex is like a rhombus,while the mikuni's is squarish - you need to fabricate an adapter so that this can be fixed.Also,a return line to the fuel Tank would need to be laid.

The accelerator rod arrangement in the Padmini would need a modification to run a cable to the Mikuni
If Only It was as easy as It sounds!!

Look at some engine pics of the Red car or the Left hand drive in my album. you will know what I am talking about
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