MFI Heat Exchangers 1970

Need some help with a technical problem - ask away and let's see if we can all help.

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8bit-ash
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MFI Heat Exchangers 1970

Post by 8bit-ash »

I'm looking at the different Heat exchangers available and see that there is MFI specific ones which seem to have an extra heat bit on. I'm 99% certain that the ones that came off my 1970E didn't have this extra bit. Can anyone advise what the differences are and ones I can use?

Cheers
1970 911E Sportomatic
2002 Boxster S
2004 Audi A2 TDi 90
Ian 2.2S
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Re: MFI Heat Exchangers 1970

Post by Ian 2.2S »

You need to have the take off on the rear outside of the LH exchanger to supply warm air to the thermostat/cold start enrichment on the MFI pump.
HTH
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Re: MFI Heat Exchangers 1970

Post by MT »

If yours was an E (i.e. with mfi) then either you had this take off because it supplies the thermostat on the rear of the mfi pump) - via two pipes and a connection in the LH tinware,- or if it didn't you car must have run like $hite!

Mick
'Creativity is the product of time wasted' Albert Einstein

1972 RHD 2.4E (ex Bob Watson racer - now in original Tangerine)
1966 LHD swb (Doctors car - now with Mrs. Ferrari in Madrid)
1966 TR4A (now sold and replaced by 1990 944 turbo)
1966 S2a Landrover
8bit-ash
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Re: MFI Heat Exchangers 1970

Post by 8bit-ash »

Is it this bit?

Image
1970 911E Sportomatic
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2004 Audi A2 TDi 90
8bit-ash
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Re: MFI Heat Exchangers 1970

Post by 8bit-ash »

this is my fella

Image
1970 911E Sportomatic
2002 Boxster S
2004 Audi A2 TDi 90
MT
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Re: MFI Heat Exchangers 1970

Post by MT »

No it isn't! I don't know what that is for, but it must be from a post 73 version - possibly an air blower input. Anyway someone knowledgable will be along soon ...

The mfi connection is on the same side exchanger, but is up near the outlet at the top of the photo - is smaller, and curved slightly downwards.

Mick
'Creativity is the product of time wasted' Albert Einstein

1972 RHD 2.4E (ex Bob Watson racer - now in original Tangerine)
1966 LHD swb (Doctors car - now with Mrs. Ferrari in Madrid)
1966 TR4A (now sold and replaced by 1990 944 turbo)
1966 S2a Landrover
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Re: MFI Heat Exchangers 1970

Post by Mick Cliff »

8bit-ash wrote:Is it this bit?

Image
No, it's the bit at the top of the LH heat exchanger
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Re: MFI Heat Exchangers 1970

Post by Ian 2.2S »

Sorry, my mistake I meant front of LH exchanger not rear. You have got that small diameter feed on your old one.
8bit-ash
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Re: MFI Heat Exchangers 1970

Post by 8bit-ash »

Cool Cheers Guys, and that pipe is the only difference between carb and MFI items? Early911S registry seems to suggest that the other exchanger part is for - " '72 and '73 had the "extra" heat section for the warm up regulator on the intake"
The MFI listed Stainless steel SSI/Dansk Units picture this bit but i'm good to assume that if mine didn't have it I don't need it?
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2004 Audi A2 TDi 90
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Re: MFI Heat Exchangers 1970

Post by Lightweight_911 »

That left side heat exchanger is for a 2.4/2.7 mfi engine - the extra outlet pipe is for the hot air feed to the 'flapper box' in the air intake to the air cleaner housing.
Andy

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- subtracting weight makes you faster everywhere”
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