911tracker85

I recently got a set of MSDS headers for my 928.

I have read though a lot of threads on headers. what I am finding is very little info on headers and 16V and optimized "tuned" exhaust systems.

since it is not a track car, not going to worry or spend too much on the rest of the exhaust to tune the last few added HP from the headers. but do want as good a system as I can get for reasonable cost.

from reading other threads, it sounds like some have spent a lot of $$ and several variations to create a tuned X pipe, dual system for the 32V.

my current direction is to get a Borla CAT back, then figure out how to fabricate a connection from the headers to it. but interested in options, especially to go a 3" all the way back for better flow than what I think the Borla may provide. if I go the fabricate path, Magnaflow mufflers will probably be my first choice.

would appreciate any ideas, pics, sources of parts to complete. my current problem is I do not have them installed yet. so really cannot see what I am facing.

getting ready to send the headers to Jet-Hot.

thanks in advance for any ideas.

NoVector

I had MSDS headers, y-pipe, no cat, and Borla cat-back on the 84 and LOVED IT! I also advanced the timing 2-3 degrees, KN filter and rising rate FPR. Unfortunately, I have no dyno numbers for you. But it did seem to hual *** better than anything around me and had a great exhaust note. I chose Borla for their life time warranty. The Y-pipe was made by a muffler shop back in Kendelville IN for $50.

Ducman82

Headers. 3" Y-to a single, race cat, to a flow master 40 series. awesome.

vanster

I have MSDS headers on my 80-16 valve along with a Y pipe. I am about to remove the pumpkin
and change to a Magnaflo and remove the center muffler. Right now I don't have a cat and the note is good. I think you should look into 3" vs 2.5". I could be wrong but you need a certain amount of back pressure to maintain HP. Ask around regarding this.
and I attribute this to the headers. I do think the headers add to the overall sound. I can't tell how much additional HP the headers add. The only other 928 I have driven is my son in laws '87 S4 with an automatic.
and stock exhaust. I didn't feel that his car was that much quicker, if at all.
One thing against MSDS headers, which I am facing today, is clutch removal. They are in the way and I am going to have to remove the right side a bit in order to lower bell housing off.

911tracker85

vanster,

did you have to fabricate the Y you have? I have a Y now that replaced my CAT and goes to the stock manifolds. I have been told it does not fit the MSDS.

I had already removed my pumpkin and resonator. resonator repl by a small, round magnaflow and pumpkin by a oval 1in-2out. currently sounding good, but a cobbled together exhaust, want to improve the sound, cosmetics and flow.

IIRC from threads, our 16V like a little backpressure for thorque, but the more open the exhaust the more high end HP you can get. I had also read the headers can interfere with some engine maintenance.

I appreciate all the repies so far, looking forward to any more options or experiences.

convinced I will need to get them installed to ultimately sort this out. but if I decide to focus on a plan for a Borla CAT back, will start trolling for a good buy.

danglerb

I think you leave substantial HP and torque on the table without a properly tuned full exhaust. I don't think the shop that did the Y pictured above quite understands how to make a merge pipe, at least one that increases power.

vanster

Bob
I found a Y pipe from one of the exhaust suppliers, can't recall at the moment
but I will look. The muffler shop adapted it. Yes maintenance is a pain as of today
I have spent 3 hours trying to get my starter out. But how often do we have to replace clutches, so it's worth it I guess
But the headers I feel do create a different overall sound.
Attached is a pic before the Y pipe
Van

IcemanG17

I got EXCELLENT gains from a single 3.5" system with dual borla shorty X1's..... 20+ HP and torque across the board......

I also agree witih the +2 timing advance...thats what I run....the 84 USA has the LEAST amount of timing of any 16V model..... its spec is 20' at 3000 (no vac) and 28' @ 5000 (no vac)......many others are 36'

I run 85-6 tubular exhaust manifold, into dual 2" pipes that attach to the single 3.5" system about where the factory cat ended....I will post some pics and dyno's shortly

NoVector

Bob - On the 84, I changed head gaskets with engine in the car, motor mounts, etc. I didn't change the OPG, but I did about everything else like PS hoses, etc. with no problems. In fact, I could even reach those damn nuts on the upper A-arm bolts and could reach/replace the window washer pump. Good luck!

That's probably true; it was more about connecting the headers to a straight pipe that went to the Borla Cat-back. But for the price, I was a happy camper. No doubt, some HP was left on the table though.

Landseer

The headers are a royal PITA to mount / remove with cross member in place.
But a cinch without, paired up with a MM / OPG job, for instance.

Clutch access is not possible without loosening one bank of the headers.
The difficulty is getting complete access to one side or the other with crossmember installed.
Its possible, others have done it, but it is a challenge.

If you do it, strongly consider SS studs. They do not gall in aluminum.
The only saving grace in my "de-installation of a 10 year old job --- those studs.
Mine had SS nuts / worked fine.

They sound awesome with some light muffling after.
Our setup had a pair of bullet mufflers and a flowmaster Y into a 3+ inch single and some kind of big chambered muffler..

ROG100

Bob,
Don't you have MM's ready to fit - ideal time according to Landseer to get the headers on.

IIRC I have a dual Borla in the workshop - does anyone know if they used to make a dual cat back for the 83/84 cars?

911tracker85

Thanks again for all the feedback, the 928 BB is a really great crowd. part of what inspired me to finally get a shark.

vanster,
thanks for that pic.

danglerb.
that is why I read a LOT of header threads. what I think is no one has invested the $$ in developing a well tuned system for 16V. one shop I contacted said there is not enough demand from 16V crowd, not as willing to spend much $$ on an exhaust as the 32V crowd. that is why I am trying to gather as much info from anyone with a 16V that installed headers. eventually, will have to take my best shot at a solution.

icemanG17,
I would appreciate any pics of your system as an example. my car is a driver not a track car. so don't want it to be too loud, but don't want to muffle down to a wisper either. but seeing your solution will help. I like people thinking my car is faster than it is.

also thanks for the timing specs. I have read it helps to advance the timing on 16V cars, but could never find a specific suggestion.

landseer,
rusted/frozen, and then breaking studs is my biggest worry about this job. just took me 2 days to wrestle / heat off the old tie rod end on my wife's 15 yr old, 145K mile audi. sigh.....

Roger,
yep, I have had a pile of parts from you for too long that need installing, incl MM. as I plan that project for this winter, is what inspired me to grab those headers. need to email you my list of remaining parts I need for my shark project.

and now in the spirit of eye candy, just got my fan/housing and K&N air filter horn back from being polished for my 911. and my painted intake. rebuilt fuel line, injectors, and misc parts should arrive in the next few days, then need to get this one done and the shark in the garage.

123quattro

Hi Bob,

I have MSDS headers on my 84. The car dynoed 227whp with them if I remember correctly. That was with a merge into a single 3" with the smallest Magnaflow muffler you can buy. Euro heads/cams added another 45whp on top of that.

Dual pipes will give you a lower tone. A Y into a single will be higher pitched.

Lizard928

yes they did. It is fairly restrictive though. One of the locals just had his borla blow out.

IcemanG17

Here is the dyno sheet, but now I can't find the pics of the exhaust...