Reviving the 3.4 exhaust debate

[Jgordon]

Hey,

First, thanks to everyone for the information so far. The last time I had this discussion, I was just finishing the engine conversion and was strapped for cash. Also didn't really know the options available.

I am selling my bike, which will mean I have some cash. I also have a better understanding of what I want in an exhaust system.

I'm thinking that the first priority is an easy swap. I don't want to deal with rerouting the heating system or cutting the engine skirt as with the SSIs. I also want to retain heat. So I'm thinking B&B or GHL. I know B&B is a relatively straight swap (might need to change an oil line?) I don't want resonance. I also don't want it to be crazy loud. I don't need to wake the dead or squeeze the final .3 hp out of the system. Just something free flowing, with a nice sound (rather go deeper than whinier).

If I go B&B, my options are a B&B muffler (which are still crap?) or an mb911 muffler (is he producing the B&B sized units yet?)
Any other choices for the B&B headers? Anyone have a set for sale?

How is GHL? I've heard good things about the company, but haven't seen many people on the board using their products. And which mufflers can fit on their headers?

Jeremy, I saw a recent thread where you are going with the B&Bs and an mb911 muffler? That might be the easiest setup.

I also have a dansk 2-in, 2-out that I bought on the understanding that I'd get SSIs. This wouldn't hook up to a GHL or B&B system, would it?

Thanks again. Let me know if I can clarify anything.

[Jgordon]

Anyone? Bueller?

[JeremyD]

Sorry, didn;t see this earlier... I think it depends on what you want.

From my research
1. if you want heat - then really the B & B headers are the only game in town. SSI are too small - fine for a 3.2. If you have an agressive cam and want to run plenty of air through there move on. No heat? go with george's european headers.

2. GHL is a great system - better than stock - but apparently (and have been told this by two highly respected Porsche car folks) that they are not equal length. I also talked to several people that have had their GHL's split - but so has B & B (mufflers) for that matter.

a dansk dual in / dual out will fit with SSI's & Euro headers (like ralph) - not with GHL or B & B.

- I'm pretty sure that after a dyno run - that Ralph was thinking of getting another muffler because he was told it might be restricting the top end a little.

Me - I bought a set of used 964 B & B headers and muffler. I have the 964 muffler (with the big tip out the passenger side) it sounds great (no resonance). But I'm also still waiting for a muffler from Ben because I want a dual out.

My car acts just like a regular 3.2 from 1000-3500 rpms. Nothing out of the normal. Now above 3500 rpms and the exhaust note becomes sharper and things start happing really quickly. So much so that last weekend - I stuck my foot into it going around a corner in 2nd gear - above 3500 rpms and broke the tires free. Actually scared me a little - because I am used to my car hunkering down and powering out of a curve...

[Jgordon]

OK, looks like I'm on the lookout for a set of used B&B's. I don't think my horsepower needs are worth spending more time sifting through the information. Do you have ben's website? I was trying to find it earlier and couldn't. Did he give you any indication of a timeframe on the B&B compatible muffler?

[ChrisBennet]

How about modified 993 headers?
-Chris

[gumba]

I made a dual in / dual out using a Flowmaster 80 for my 3.4 race motor so I could drive it on the street. I also made some baffle inserts to quite it down even more. I was surprised how quite it is. The muffler is about $80.00 and the rest of the parts were about $50. I was up as SSI a few months ago and the owner was telling me he was going to make a 1 5/8" heat exchanger. Don't know if that's large enough for your application.
'74 RSR w/3.4 twin plug & carbs.

[Jgordon]

Chris, how would the modified 993 headers work? would they retain heat, bolt on application? I thought the 993 used separate mufflers, or is that the 996 only?

[ChrisBennet]

Originally posted by Jgordon
Chris, how would the modified 993 headers work? would they retain heat, bolt on application? I thought the 993 used separate mufflers, or is that the 996 only?

The 964/3.6 conversion guys use the 993 heat exchangers somehow and they have heat. You need to flip the flanges on the one of the the exchangers and fab up a muffler setup. I don't know the specifics but a friend of mine fabbed something up for a customer of mine for a 964 motor and he was very happy.
-Chris

[Slider79SC]

The 993 exchangers are not equal length... won't this affect performance?

[Slider79SC]

[Slider79SC]

[Jgordon]

I'm looking for a system I can install on my own, with no welding tools and no second car to drive while this one's on the lift. 993 adn fabbing mufflers are definitely out of my bag of tricks. Seems like it'd be cool though.

[911-32]

89911 uses SSIs on his 3.4 with 964 cams and some other goodies. If memory serves its a 280+hp motor. Are the SSIs really holding back this engine? Even if they are, the SSI party line has always been that the slight top end loss is more than offset by gains in torque.

FWIW, the SSIs are super quality, match with all sorts of mufflers, give great heat and are reasonably priced. Yes, you have to do the oil line change and using the existing heat is difficult (though not impossible) if you really don't want to backdate the heat (which in itself is not too hard). Just my $0.02 - yes, I bought SSIs for my modified 3.2.

[DW SD]

I spoke to the proprietor who makes SSis. He said his exhaust is great for engines up to 275 crank horsepower. 280 HP = roughly 322 at the crank. After that, there are pumping losses, but you should gain in the mid range. I had a conversation with Tyson Schmidt a few weeks back, asking his opinion. He suggested using the 993 HEs and flipping the ports to mate 3.2 style heads. I think Ben (MB911) may soon make an appropriate muffler for 993 HEs to dual outlet mufflers. If you can get someone to make up the 993 HEs, you'd have a bolt-on package. If you are not seeing more than 275HP at the crank, SSi's should be a good setup.

Doug

[KTL]

I've seen SSI's on a 964 3.6 and the guy claimed it didn't feel like it was being restricted. Motor was installed by DeMan Motorsports and they're supposed to be pretty good. So maybe they're not a huge choker?

Too bad you want heat. Though I can completely understand why. It's nice to have.

Otherwise, i'd give George's Euro. Headers and a Triad muffler a try. I don't think you can get better bang for the buck than that, if headers are what you want.

And those considering going the Flowmaster route, i'd strongly recommend a Dynomax muffler. Sound is still great, while much more tolerable than the Flowmaster resonance king. einreb's (Bernie) 3.6 in his '88 sounds downright awesome with this muffler. Kinda sounds like a sportbike.

[Jeff Alton]

Does anyone have Dyno info to back up any of this? It seems that there is so much opinion around about what is too small and what works and what doesn't, but no imperical data.

I am putting a 3.4 twin plug together this winter and have both SSI's and a set of 993 HE but not sure what ones I am going to put on.

Cheers,

[DW SD]

I think Tyson has been talking with Steve Wong about doing a dyno run. Hopefully, he'll do that and let us all know. To be clear, he has a 3.2L, but he still runs modded 993 HEs.

Doug

[Slider79SC]

I would also like to know what performance losses the 993 exchangers cause since they are not equal length?

For a turbo application I know that it is no big deal but on a NA motor it is....

[klaucke]

You can get a muffler to work w/ the stock 3.6 exchangers, i.e. Timmins Happy crab (to fit under a impact bumber valence):



taken from this thread: http://66.236.61.177/showthread.php?postid=1755757

Triad also makes one:




Pics taken from this thread: http://66.236.61.177/showthread.php?threadid=237499&highlight=3.6+exhaust+options

Then I suppose the 993's would be a bolt up, and would flow more freely and be better suited to a 3.4 than the SSI's. I am assuming emissions are not a concern?

[Jgordon]

That's the other reason I'm looking for a bolt on solution. I have to take these things off every year for inspection, and don't want to be without heat should I be unable to find the time to replace following the inspection. Seriously, I'm not sure where you guys are finding women that don't care about heat in a car. Plus, when it's 35 degrees and sleeting out, I confess to enjoying the heat myself.

I'm curious - what material does B&B use? There's a set for sale in this thread , but it looks kind of beat up.



What do you guys think as far as the condition goes? Fair Price?