Philip in the US writes:-

Re: Biturbo E numbers?

"Enrico,

Thank you for the input.

Some of the history I have found I will pass on:

the 1985 Biturbo E (US west coast release) was a 2.5l V-6, had factory two-tone paint scheme (lower body panels black below trim), and was the first Biturbo offering twin intercoolers (air to air or air to liquid [spearco design]). Additional badges were added above (liquid intercooled and beside (a large E) the Biturbo ensignia.

I have heard approximately 250 were made but that number seems elusive.

v/r

Philip."

Reply from Enrico:-

Re: Biturbo E numbers?

"Hi Philip,

I'm often contacted by enthusiasts seeking more information about their 'pride and joy' and restorers/dealers seeking information as to the 'hopeful' rarity of their Biturbos and the possible increase in value. The short answer is that at the moment there isn't much in the way of residual value following the restoration of a Biturbo of any type, except possibly a Shamal or a Ghibli Cup.

The only people with accurate information on production numbers including 'limited series' are the manufacturer and the importer. The Maserati Biturbo, following its initial launch, was a notoriously slow seller. For this reason many importers commissioned 'limited series ' of their own. Sportier wheels, side skirts, front and rear spoilers etc.

Here in the UK we had an SE version of the Biturbo (see attached image).

Reply from Philip:-

Re: Biturbo E numbers?

"Enrico,

Thank you for the input.

Some of the history I have found I will pass on:

the 1985 Biturbo E (US west coast release) was a 2.5l V-6, had factory two-tone paint scheme ( lower body panels black below trim), and was the first Biturbo offering twin intercoolers( air to air or air to liquid[spearco design]).

Additional badges were added above (liquid intercooled)and beside (a large E) the Biturbo ensignia.

I have heard approx. 250 were made but that number seems elusive.

v/r

Philip."

Luis in writes:-

Re: Biturbo engine swap

"Hello,

I have a Maserati Biturbo 2.0 SI 1987 (AM471), I have this car for 5 years, but I only drove the car a few times, I first have restored the car (2 years) then I hit the ground, ran out of oil and ...destroyed my engine.

Now I am replacing the engine with the engine from a Ghibli 2.0 (AM496), the type with the distributor and without catalytic convertors, with the 6-speed Getrag box and the pull clutch system. I have the Biturbo manual and the manual from the Ghibli without the distributor (I think this is a newer model). I am looking for the manual for the older Ghibli to do the electrical connections because these are very different.

I also want to place the Ghibli instrument box, these connectors are also different.

Can you help me please?

Thanks,

Gunther."

Reply from Enrico:-

Re: Biturbo engine swap

"Hi,

I am afraid that Maserati did not produce any workshop manuals for the series one Ghibli. Your Biturbo manual should have details of the 24-valve engine.

No manual gives instructions on changing a Maserati from an 18-valve engine to a 24-valve engine and all the possible problems that will ensue, let alone changing the instrument binnacle at the same time. The only person that could possibly assist you is someone who has carried out the same conversion and those you could probably count on the fingers of one hand.

Theoritically a kit car manual may be of more use as that is what you will end up with. The car will no longer be a serious proposition to a Masertati collector.

I believe your cheapest option is to buy an early Ghibli, they're cheap enough at the moment, and you already have an engine replacement if you bottom-out again!!

I'm sorry I can't be of more help.

Regards,

Enrico."

Luis in writes:-

Re: Biturbo

"Hi Andy and Enrico,

I recently bought in Florida a desert gold Maserati Biturbo Si from 1987 (fuel injection engine). Its body is in pretty good shape with no rust, the engine starts and runs well, but the 5 spd. manual transmission has a loud bearing noise while on 1st., 2nd., and 3rd. gears. The noise disappears when you engage 4th. or 5th. gears. Will this discard the clutch bearing as being the cause of the noise? Would you think it is an interior transmission bearing instead? If the latter is the case, do you know where can I get a bearing and seal overhaul kit for this ZF transmission box? I would appreciate your impressions.

Regards,

Luis."

Reply from Andy:-

Re: Biturbo gearbox problem

"Hi Luis,

I’m afraid that this is definitely a fault with the gearbox layshaft bearings which means a stripdown. If you are lucky, you may be able to just renew the layshaft support bearings and others and seals and gaskets, but if there is significant noise which goes away in fourth, then it probably means that the gears are worn and at that point, the most cost effective way to deal with it is to look for another box.

Andy."

Christian in France writes:-

Re: Biturbo

"Hello I to write to you because you seem to be of the specialist Maserati.

Voila I have two Maserati Biturbo. One needed some odd jobs to the bodywork and was out of action for around seven months. When I started her up, I noticed that all the instruments were no longer working (re counter, speedometer, gauges, and warning lights) also the indicators.

I checked the fuse, no problem there. I also removed the alarm but the problem is still there. Can you help me solve this problem as I can't find a Maserati specialist able to do so.

I thank myself you in advance.

Christian."

Rick in the USA writes:-

Re: Biturbo i

"Hi,

I just bought (today) a 1987 Biturbo i. I had a couple questions but found them already asked and answered here. Just wanted to thank you for your efforts and as I am a complete novice with this automobile, I am looking forward to many hours of reading your pages now and in the future.

Thanks Again,

Rick."

Reply from Enrico:-

Re: Biturbo i

"Hi,

Please excuse me while I take a moment to recover from the shock!!

At long long last a satisfied customer, well worth waiting for.

I'll pass on your thanks to Andy and all the other contributors who are mainly responsible for the good advice. I'm afraid I can't take all the credit.

Regards,

Enrico."

Frank in the UK writes:-

Re: ZF Gearbox

"Hi,

Please can you help. I have been told that the 5 speed Biturbo ZF gearbox will fit the Alfa V6 engine.

Do you know the ZF part number as opposed to the Maserati one as a ZF 'box is probably common to more than just the Maser.

Also do you know if an adaptor plate is required?

Any help greatly appreciated.

Regards."

Rick in the UK writes:-

Re: Biturbo gold clocks

"Hi,

I am looking to buy a large number of the Biturbo gold clocks, do you have any idea where I can get them??

Cheers Rick."

Reply from Enrico:-

Re: Biturbo gold clocks

"Hi,

Why would anyone want a 'large number of Biturbo gold clocks'? Do you have a large number of Biturbos without clocks?

I think you'll find that most dealers who have clocks, know their rarity value and will keep them for owners who need them for their cars. Normally the clock is the first thing that's removed by a car breaker!!!

Have you tried Meridien-Modena? David Askew? Bill McGrath Maserati? Auto Shield? Eurospares? Try phoning around car breakers. Regards,

Enrico."

Richard in Holland writes:-

Re: Biturbo 1982

"Hi,

I've just bought a Maserati Biturbo 2000 cc from 1982. It was running pretty good with a fine accelaration.

But when the engine was cold, the engine stalls when I have to stop, brake or reduce speed. When the engine was warm, this still happens when I have to stop for a traffic light. Also after 30 miles or more.

Now I have checked some things, like; tighten up some screws from lines and tubes and checked the spark plugs.

But now, when the engine is on temperature, I have to run 3000 rpm to get away from the traffic lights without having the risk of stalling the engine. When it stops it is difficult to start the engine again.

This aspect appeals very unsafe to me and makes me nervous when I drive.

Does anybody know what this can be?

Thanks in advance.

Richard."

Reply from Andy:-

Re: Biturbo stalling

"It sounds as though the carburetor idle jets are blocked. This is quite common and requires the carburettor cleaning to repair.

Andy."

Cristi in Romania writes:-

Re: Biturbo 1983

"Hi Henry, Like I've told this car is killing me. I replaced the engine with another. My old engine was a AM452/09 with air-cooled turbos. The new engine which I have now is a AM470. A better engine...turbos are water-cooled. But.....never say never.....when I start this engine it runs like new one. The indicator from turbos it reach the yellow zone (on dashboard)...now it doesn't.

My question is why????????? The engine runs very well but 0-100km/h in 8-9 sec is very low I think. The old engine runs in max 7 sec.

I changed also the rims from 14-inch to 15-inch...it could be a problem..I think not.

Can you please help me with an advice about turbos. Can I raise the pressure in turbos (if yes how?) or what can I do because I know this engine can run much better than that.

I'm sorry to say but here in Romania we have very low income...around 200 euro/month and it's very hard for me to maintain this car. I have wife and a little girl. I'm a truck driver. I work a lot and I'm very disappointed when I spent big amounts with this car and finally...doesn't work at all. I hope you understand me ....I'm not wail I'm just telling you.

I bought another car for this new engine... with 1700 euro.... my wife will kill me if she find out.

Once again please help me you are my only hope anf forgive me for being so insistently.

My best regards and hope to hear from you soon.

Cristi.

P.S. This is the second time when I send this email. Sorry for being so Insistently."

Reply from David:-

Re: Biturbo lack of performance!

"Hello Henry,

He says the turbo reaches the yellow zone, did it do this with the new engine and now it doesn't? His description is not clear.

If it did reach the yellow and now it doesn't,---------------

1. then first he should check for a leak of air between one of the turbo's and the intake, this will be the most common failure.

2. Check the turbo's are spinning, remove outlet pipe to see.

After this there maybe numerous reasons of which I am no expert but am willing to help. I suggest you tell him the above as it is most probable, provided he did have boost to the yellow on the new engine and now he doesn't. e.g a hose is loose!!!!!!

All the best.

Ciao,

David."

Issac in the USA writes:-

Re: Biturbo 1985

"Hi,

I just purchased a 1985 Maserati Biturbo, and I have some troubles starting it. When I turn the key on, the instrument panel lights don't light up, I cannot use the power windows and the car will not start. If I wait long enough, the warning lights on the instrument panel light up and then everything seems to work fine.

During the waiting period, the fuel pump or something seems to make some odd noises. This only happens when the engine is cold or semicold. I was wondering if this waiting period is normal at all, and even if it is mine seems to take an excessively long time.

Any help is much appreciated. I was also wondering how to tell if my car is an E model. Above the visor it shows the tire specification size to be 205/60/VR14 which I think is one of the upgrades on the E version, but the car has 195/60/R14 tires on it. VIN number is ZAMAL1101FB313096 if that helps at all.

Thanks, Isaac."

Cristi in Romania writes:-

Re: Biturbo 1983

"Hi Enrico,

I've changed the engine last night. It's a later engine from a Masertai from 86-87 with water-cooled turbos. It works fine, much better than my old engine.

I want to ask you if you can tell me some specifications about my new engine. Model is AM 470.

Thanks and have a nice day.

Cristi from Romania.

P.S. I will send you soon new pictures with my Maserati."

Joe in the USA writes:-

Re: 1987 Biturbo Si

"Enrico,

I have a question that I figured you would likely know the answer to.

I currently own an 87 Biturbo Coupe Si, Which, if my info is correct, has IHI RHB51 turbos installed.

I have recently found a couple of turbos for a 93 2.24 for sale and was wondering if these units would fit my vehicle. From what I could find, it appears that these are RHB52s, which are slightly bigger and possibly have ball bearings. Do you know if this information is correct?

Do you feel that putting these in my vehicle, if they fit, would provide any benefit?

Additionally, do you know of anyone who makes a performance 'chip' for this vehicle? My 87 Coupe Si has a 2.5L fuel injected engine.

Thank you for your time.

Regards,

Joe."

Reply from Andy:-

Re: Biturbo turbocharger numbers!

"I have to admit that I am not an expert on IHI numbers, but I believe that your car would have the smaller turbos fitted to the carburettor cars in the UK and that a 2.24v. would have the larger version. It is not a simple case of just swapping them over as the wastegates are also different and there is no real performance gain to be had anyway. What I do know is that both turbos would have been ball bearing type.

I also do not know of anyone who makes a performance chip for this car, sorry!

Andy."

Reply from Enrico:-

Re: 'Biturbo' performance chip!

"Superchips supply a performance chip for the following models. You would have to check with your local Superchip agent in the US to check whether any of them would suit your car.

I have no personal knowledge of its performance or reliability.

Regards, Enrico."

Cristi in Romania writes:-

Re: Biturbo 1983

"Hello,

I'm Cristi from Romania.

I have several problems with my Maserati last weeks. Now it's dead. The engine brokes two times last week.

First time a piston it's broken. It has big hole in the aluminium part. I change it with another from a broken engine that I have.

This Saturday I intended to go at a showroom in Bucharest but again the engine let me.........I feel I'm going crazy. An axcame it's bloked and the cambelt it's ..........I don't know. I'm too angry to write any more.

What I want to ask, it's if you know somebody who has a Maserati engine for sale.

Thanks in advance for your kindness.

Regards,

Cristi."

Ian in the UK writes:-

Re: Biturbo 1988

"Hi Henry,

I've just changed the front wheel bearings and have taken a note of the numbers:

TIMKEN Cup Roller Race

Outers LM11910 LM11949

Inners LM67010 LM67048

Oil seal NTK1130 SC250 175 31

Regards,

Ian."

Peter in Canada writes:-

Re: Biturbo knock sensor!

"Hi Henry.

Trust all is well.

I am putting the intake back on my 86 425 and have a few questions about the Biturbi knock sensor. There are 3 connections and I assume that one is for power, one ground, one signal to MABC.

So, is the knock sensor in the always "on" position, that is to say, when the engine is running normally, the signal to the MABC is on and the "knock" signal from the microphone stops the signal to the MABC or is the knock sensor "off" and only sends the signal if the microphone senses the knock.

In either case, do you or any members know the voltage or impedance of the signal from the third wire? If I know this, I should be able to measure the third wire output and cause the signal to open or close by tapping the sensor. Make sense? I believe my sensor is working fine and my valves are a bit tight as the boost will not go to the yellow . I am changing and sealing all of the gaskets and changing the hoses but really don't want to re-shim unless that is the problem.

And finally a quick question. How can one check the condition of the waste-gate with turbos on car?

Peter."

Reply from Andy:-

Re: Biturbo knock sensor!

"I am afraid that I have no info on voltage etc for the knock sensor. They are very reliable in my experience and any problems in that area seem to originate from the connection to the sensor which sits over the cam cover.

The valves would have to be seriously tight (and therefore requiring shim job) if they cut your boost down.

You can look at the wastegate seats if you take off the exhaust system and the wastegate housings, which is not that difficult unless the nuts are seized but better to check spring tension first, then air line them open and closed to make sure they are not seized.

Andy."

Another reply from Theo:-

Re: Biturbo knock sensor!

"The Biturbo knock sensor, which is the same as fitted to SAABs with the APC system, is an analogue sensor and not an "on-off" digital sensor. That means it doesn't just turn a signal on or off at the presence or absence of engine knock, so the impedance measurements you are suggesting to do will not tell you anything. The sensor is in effect a microphone that constantly conveys engine 'noise' to the MABC. An analogue amplifier is used in the MABC to "listen" to the engine and determine if knock is about to happen. As a safety feature, a feed is taken from the knock sensor within the MABC and amplified 20 times more than the normal, "knock sensing" feed. The noise on this extra amplified feed is used to determine if the knock sensor is connected to the MABC since with the extra amplification there should always be noise present. If no noise is detected with the extra amplification, the MABC assumes that the sensor is either faulty or disconnected and goes into a safety mode and keeps the waste gates open to avoid over-boost. This is why there's very little turbo boost if the sensor is disconnected altogether or if there's a bad electrical connection to the sensor.

Regards,

Theo."