964 3.6 heater backdate options

[ToddM]

What are the blower motor removal and heater backdate options for the 3.6l engine?

Will the old style heater backdate -89 work on a 3.6 mated to SSI HEs?

[Bill Verburg]

Why not leave the stock 964 heater bloer & ductwork in place?
like this, 964 engine in my C3


and

ssi are too small for that motor and aren't set up for 964 or 993 style heat.

the solution?
use B&B w/ 964 heat inlets and 911 heat outlets, combined w/ stock 964 heat tube

like this

[PSportoVeloce]

Originally Posted by Bill Verburg

the solution?
use B&B w/ 964 heat inlets and 911 heat outlets, combined w/ stock 964 heat tube

like this

one of the problems with this however is that the placement of the inlets on the muffler (or heat exchanger outlets if you prefer) is proprietary so you can only use B&B mufflers.

[Bill Verburg]

Originally Posted by PSportoVeloce

one of the problems with this however is that the placement of the inlets on the muffler (or heat exchanger outlets if you prefer) is proprietary so you can only use B&B mufflers.

That's not a B&B muffler on my car.

No, you can't use standard 911 mufflers. But the fact remains, ssi are too small for a 3.6


I went through all this pre internet, here is an early iteration of the exhaust w/ ssi and cat tips, not a good setup at all, circa 1994

[ToddM]

Because :

1. I want to remove the blower unit for weight saving
2. My blower motor took a dump anyways
3. The B&B muffler you have to run with this system is garbage
4. Although i agree the B&B solution is the best "street performance solution" you can get ported 3.6 SSIs now and run a stock muffler

The only attractive thing about the B&B is that you can leave the HEs in place, and swap out the cat & B&B muffler with the bypass tubes and stock muffler... this is the most expensive approach but then you are only swapping out half the system every 2 years; not the entire system

Anyays, none of this address my original question

[Bill Verburg]

1) ok, then pull it and use an RS heat tube
3)again, you don't see a b&B muffler on mine, there are a # of choices for that
4) I have no idea what ported ssi's are, but the fact remains, ssi's are too small for a 3.6. every ssi ever made uses 35mm ID primary tubes

but if you insist on using ssi's take a look at the 3rd pic I posted. It's a 964 in a '76 C3 w/ ssi's

[JeremyD]

or you can use 993 heat exchangers and an MK muffler -

[ToddM]

From Patrick Motorsports:
"WE WORKED WITH JOHN @ SSI TO DEVELOP THE USE OF HIS OUTSTANDING HEAT EXCHANGERS SET IN OUR 964 & 993 3.6L ENGINE CONVERSIONS TO 911 - THIS THICK HEAD FLANGE TYPE HAS A SPECIAL TAPERED INLET PORT FOR THE 3.6L HEAD"

I was told that the RS bypass tube was the wrong thing to use with SSIs

[JeremyD]

[JeremyD]

Originally Posted by ToddM

From Patrick Motorsports:
"WE WORKED WITH JOHN @ SSI TO DEVELOP THE USE OF HIS OUTSTANDING HEAT EXCHANGERS SET IN OUR 964 & 993 3.6L ENGINE CONVERSIONS TO 911 - THIS THICK HEAD FLANGE TYPE HAS A SPECIAL TAPERED INLET PORT FOR THE 3.6L HEAD"

I was told that the RS bypass tube was the wrong thing to use with SSIs

Tapered? WTF? ask em what the primary tube size is after the "taper" When I asked about it the answer was that from a tooling standpoint it was too expensive to produce for larger engines (larger than 3.2's)

Primary tube size
SSI 38mm OD/ 35mm ID
GHL 41mm OD/ 38mm ID
B&B 41mm OD/ 38mm ID (small tube)
B&B (964 version) 44.5mm OD /41mm ID (large tube) too big for a street 3.2
SC/RS 42mm ID

[ToddM]

I know I can get the 993 HEs, get the flanges flipped, then custom fabricate something but I really wanted to avoid that.

I'd reallly just like a bolt-in solution

[Bill Verburg]

Originally Posted by ToddM

From Patrick Motorsports:
"WE WORKED WITH JOHN @ SSI TO DEVELOP THE USE OF HIS OUTSTANDING HEAT EXCHANGERS SET IN OUR 964 & 993 3.6L ENGINE CONVERSIONS TO 911 - THIS THICK HEAD FLANGE TYPE HAS A SPECIAL TAPERED INLET PORT FOR THE 3.6L HEAD"

I was told that the RS bypass tube was the wrong thing to use with SSIs

Who ya gonna believe?

[JeremyD]

pretty sure steve weiner has a solution - bolt up using custom GHL with normal muffler spacing and early car heat boxes. Call him - just be prepared - they are $$ [but bolt up]

[ToddM]

Hi Jeremy

yeah I beat ya to the punch, Uncle Stevie and I were talking about this a couple years ago

Steve is def one of the go-to guys, and a hell of a nice guy at that

[Steve W]

SSIs, tapered or not are really too small for a 3.6, tapered at the inlets or not. They all are 1 3/8" ID primaries, while the original heat exchangers are much larger. They're too small for a 3.4, and also limit the top end hp of a 3.2. Unless you don't care that you will loose 14-20 hp at the top end, do it right or stay with the stock heat exchangers until you can do it right.

[RideShoot&Drink]

Bill, I'm about to start my C2 engine into 87 chassis conversion.

I have some questions:

1. Is 964 heat tube plug'n play into B&B headers or any modifications required?
2. I was under impression that C2 heater blower doesn't fit and has to be replaced with smaller Carrera or SC units, am I wrong? It doesn't look as nice as RS tube, but real heat in my case is more important than looks or weight savings.
3. Also, looks like you left stock airbox, I thought it doesn't fit, am I wrong again?

Thanks in advance.

[RideShoot&Drink]

ToddM, I have a set of 993HE's with 993 heat tube and Timmins happy crab dual out muffler that I bought from TRE. It is pretty much plug'n play solution for what you need, but you do need to rotate the flanges on HE's. I bought it for my 3.6 -> 87 conversion, but found set of B&B headers with muffler. Email me for details if interested.

[ToddM]

Originally Posted by RideShoot&Drink

ToddM, I have a set of 993HE's with 993 heat tube and Timmins happy crab dual out muffler that I bought from TRE. It is pretty much plug'n play solution for what you need, but you do need to rotate the flanges on HE's. I bought it for my 3.6 -> 87 conversion, but found set of B&B headers with muffler. Email me for details if interested.

The 964 heater blower will fit into an SC/Carrera... I dont know why I hear people say this. My SC has this arrangement.

I have heard of a lot of failures with the happy crab

I think I am going to get the GHL solution from Steve over at Rennsport. This way, I can run the GHL straight into the Dansk then when I need to smog, remove the Dansk and use the GHL cats + muffler.

See you are also in the bay area so you have the same issue with the CA smog police. I am lucky because my car actually has the referree sticker from the state of CA that it is a legal conversion.

[RideShoot&Drink]

Originally Posted by ToddM

The 964 heater blower will fit into an SC/Carrera... I dont know why I hear people say this. My SC has this arrangement.

Oh that's great! My car will be a daily driver, so need real heat on those foggy mornings. Thanks for the info.

[Joeaksa]

Hey guys!

Bill V has forgotten more about 3.6 conversions and their exhaust systems than most people will ever know. As well is the absolute guru on 911 brake systems.

Unless you like doing silly things, wasting money and losing bets at the bars and tracks, please do not disregard his advise and experience on these subjects involving a 911. YOU WILL LOSE!

I know Patrick and use them but the SSI's are still too small for the 3.6 unless you do not mind losing some high end power due to tube size.

Also, if Steve Wong AND Bill Verburg says the same thing, its prolly a very good idea to listen to them. Both are experts in their field....

Just my 2c worth... and I do not have a dog in this hunt, justs saw the discussion.

Joe A