1988 Carrera 993 Heat Exchanger Installation Question

[robcf]

Hi,

I have searched the forum and google, I have not seen a yes or no answer to the following question:

When installing 993 heat exchangers in a 3.2 Carerra G50, is an oil line backdate required? i.e the following part numbers:

Crossover pipe - 91110773910

Crossover to thermostat - 91110772910

Thanks in advance.

Rob

[$ Short]

When I put 993 HE's on my 88, I did backdate the oil lines. I will have go research if those were the part numbers.

[wayner]

Mine is not an 88 but the same idea regarding oil lines

Note the lack of underslung oil line
Used this instead: Elephant Racing 1B - Universal Crossover Pipe - Specialty Type - 0180000

The elephant site has some good diagrams. You can buy the part here on Pelican.
1A is the usual crossover line. 1B is the over the top version as see (or not seen because it goes up and over the transmission) on my car.
http://www.elephantracing.com/oilhandling/oil-lines/911-oil-lines.htm
You can buy the part here on Pelican.
I'd call to confirm that there is nothing up top on yours to interfere with it.



Here is the picture of mine from post 457
Saving a 73 from the crusher...

[911pcars]

Part nos. 15 and 16 respectivelty:

View from LR:


Sherwood

[ischmitz]

I think yes you need the back-dated line since the regular oil line cross-over line at the rear of the engine will interfere with the muffler mating to the 993 HEs. See here for my installation in progress. I also installed the aluminum heater distribution pipe to make use of the hot air from the HEs

[robcf]

Thanks all for the feedback - simple answer is yes a backdate is required.

Wayner - FYI the universal crossover pipe does not fit an 88 because it is equiped with a G50 transaxle.

One final question, is there any particular stud length required when fitting the 993 HE's? The orriginal studs are 51mm in lrnght, however, I have seen reference to a 993 stud part number which is M8 x 22mm (PN 999 062 007 02).

Is a shorter stud required?

[robcf]

A little more digging leads me to a 38mm stud of following part number is the replacment for a 993: 900-060-106-01-M260.

There are also two options for studs from the host which reference the correct model year, one is more than half the price of the other:

999-062-237-02-M260 - Cylinder Head Exhaust Stud (intake, M8 X 51mm, 12 required, sold individually), 911 Carrera (1984-89) $2.00

999-062-239-02-M58 Cylinder Head Exhaust Stud (exhaust, M8 X 50mm, 12 required, sold individually), 911 (1980-89) $4.25

I plan on replacing the exhaust studs while I'm there, any idea which stud is required when fitting the 993 HE?

[robcf]

Bump

[faverymi]

Gentleman.

What would be the benefit of this upgrade? Never heard of it.

Bump to the top.

[911pcars]

Originally Posted by robcf

A little more digging leads me to a 38mm stud of following part number is the replacment for a 993: 900-060-106-01-M260.

There are also two options for studs from the host which reference the correct model year, one is more than half the price of the other:

I plan on replacing the exhaust studs while I'm there, any idea which stud is required when fitting the 993 HE?

I'm currently refurbishing a 3.2 and have modified and test-fitted a set of 993 HE. I didn't notice a need to replace the factory studs (a function of the thickness of the HE flange) and the threads below don't mention any stud length issue. FWIW, re-clocking 3 exhaust flanges changes the access to R&R certain HE fasteners, and longer studs may compromise installing the exhaust nuts.

What would be the benefit of this upgrade? Never heard of it.

The factory two into one system is somewhat restrictive, especially with the factory cat. converter. Early heat exchangers and the almost identical popular SSI replacements are 1 1/2" ID, not ideal for larger displacement engines (3.2 >). 993 HEs are 1 5/8". Despite they're not equal length, they're less restrictive (better top end). They require some add'l fabrication to adapt to the muffler of choice. However, they're also quality SS, provide cabin heat and are a cost effective alternative to pricier and more fragile aftermarket exhaust systems. More info in these threads:

964 Heat Exchangers in 3.6 Conversion
993 HE's on 3.2, flipping flanges
Muffler options for 993 Heat Exchangers with flipped flanges

Sherwood

[robcf]

Hi Sherwood,

In all my searches I also could not find a reference to the stud length being a problem. In any case, I've gone and ordered a number of shorter studs in addition to the orriginal replacments to evaluate if there is an oportunity to improve heat exchanger installation.