Chip and exhaust? Or is exhaust enough?

[NoLift911]

Question,

84 3.2 Carrera

Recently installed the RUF Sport Muffler 1 in 2 out, Fabspeed Pre-muffler. Good gains, good sound, happy!

Enough is never enough. From the research I have done and the articles read I wasn't sure if Bruce ever said the chip helps. I read his exhaust write up and it said for the money go exhaust and not the chip...but both together? Any gains to be had?

Custom chip or regular old welmeister dealio?

Any luck with this setup and gains..worth it?

-Jeff Kramer

[masraum]

I believe (definitely not an expert) if you change something like the exhaust or intake there will generally be something to benefit from remapping the DME. I would think custom would be the best and if there were any benefits from a "retail" chip it would just be luck since those are designed around taking a stock system closer to the limits. I think it is a rare thing to find someone who can do proper custom maps.

Just my .02 which in todays economy are probably worth 1/4th that price.

[RSupdate]

In referencing B.A.'s comments on his findings in the modifying of a 3.2 ltr, I believe you are refering to the "best chip is probably an exhaust change" comment he made.
The exhaust change he was refering to was the replacement of the stock factory system with a set of SSi's along with a 2 in 2 out "sport muffler". With that combo him & Jerry Woods were able to get an add'l 13 h.p. out of a 3.2. By comparison they were able to squeek 20+ h.p. out of a 3.0.

I'll bet you probably got some good gains by just the feel of the exhaust mods you've made. but there is still room to improve by having all exhaust tubes of equal length (i.e. headers) which is what the SSi's provide.

Unfortunately you probably have to consider smog laws and inspections so the SSi's are probably out.

There are add'l small gains to be had with the addition of a chip to your free'r flowing exhaust. I would recommend getting a custom chip mapped out for your particular engine. If yr paying the $$$ get the most you can for it.

Good Luck !!

[GeorgeM]

Drop Steve W an email, he makes chips.

[Wil Ferch]

Guys:
In reading both the original question and some of the responses...I'd like to add:

1.) SSI's make the best gains...but... replacing the cat with a true, Porsche pre-muffler ( not test pipe), combined with a dual-out mod ( or replacement) muffler, gets you *very* close to SSI, but you lose a bit in mid range torque. Nice compromise in that no oil lines need to be changed and you can easily re-insert a cat for whatever reason ( annual smog checks).
2.) the American-spec 84 and 85 versions of the 3.2 were delivered to comply with USA grade 87 gas. The later "paper" upgrades in hp to the USA 3.2's ( like 87-89 models) were....in part...due to more aggressive chip mapping...by requiring premium fuel.

Having said that, there is ample reason to believe that even a stock ( good) chip on an 84 and 85...along with the mods already done...should be worthwhile, since the drill is usually more aggressive timing that needs 92 ( US basis) octane fuel...much like what the factory did for 87-89.


Data point...I have a stock USA 85. At one time it had a stock cat, KN filter, drilled airbox, dual-out stock modified muffler, and a chip. Dyno result?... 200 rear-wheel ( ! ) hp. If you take a 12% loss for drivetrain, that would be about 227-228 hp at the crank. Factory specs say 200 hp at crank which I never believed anyway, based on the car's good stock performance. I've since added the Euro pre-muffler and feel a *definite* seat-of-pants improvement in spool-up and mid-range torque. Hope to dyno this new combo soon.

---Wil Ferch

[NoLift911]

All good info.

What I gathered from the BA article was that the setup I have is close to the SSI deal but like Wil said not quite there.

I am going to forego the cost and pain of SSI installation and leave the exhaust as is.

I do feel a chip, especially since mine is an 84 with conservative mapping would be a worthwhile addition to my setup and eek out a few more ponies.

Who is Steve W? Where did you get your chip Wil? What is the cost range I am looking at for a chip?

Is it possible to explain the mods on the car and have a chip built for you or does this require dyno tune and test time? I hear Fabspeed does this with Cyntex chips, not sure of the cost.

Also on the drilled airbox, mine is stock but I do have a K&N. I was going to go with a cut out style air box, essentially just the frame or do you think drilling is better? It is obviously cheaper.

If you drill the box do you still retain the "horn" on the box?

Thanks.

-Jeff Kramer
nolift911@hotmail.com

[Steve W]

Thanks for the plug George. Wil is right, the difference between the 84-86 car's hp and the 87-89 hp is the factory rated 200 vs 217 hp. The difference was primarily in the ignition timing and fuel maps. Take a look at the ignition timing of these two years, and you will see that the later cars have a more agressive ignition timing, especially in the upper range, bumping up your hp. Earlier cars were conservatively mapped to deal with the fuel issues of the early 80s. Notice at 6000 rpm, where peak hp is rated, Porsche has bumped the ignition timing up by about 3 degrees at full throttle. Also notice in 89 Porsche bumped up the timing substantially of the in the lower part throttle range to increase the low rpm torque in the everyday driving range.

84 ignition map


89 ignition map


Now look at the fuel maps between the two years and you'll see a slight increase in fuel given to the later cars, in the part throttle maps, primarily in the upper load regions. This increases the amount of fuel enrichment on sudden throttle changes during acceleration.

84 fuel maps


89 fuel maps


Even with all the changes Porsche did to increase power on the later cars to 217 hp, they still mapped the car conservatively for owners operating their cars under the worse conditions using the worst gas. If you use premium unleaded, the best way to bump up the hp even beyond the later cars would be to chip it with a more agressive chip to take advantage of the extra power from the higher octane.

[NoLift911]

I sent you an email Steve, very interested.

-Jeff Kramer
nolift911@hotmail.com

[RSupdate]

EXCELLENT POST STEVE !!!!!

Meat & Potatoes with no fluff..(roar of applause...)

Thank you very much

[KTL]

Jeff,

If you can locate a stock airbox lid from a used parts supplier, then you can make one of those "motorsport" lids similar to what Fabspeed sells in carbon fiber for something considerably less than $175!

I just took a coping saw to my spare airbox lid and cut the face of it off. You definitely get a throatier sound under hard/full throttle acceleration. Can't say if it's any faster, but it sounds faster.

If you decide to drill the lid, I don't think it matters if you leave the snorkel on there. Probably better to leave it on as it pulls some incoming air from the airstream going to the motor cooling fan? Maybe.

[Kurt B]

G-tech estimated my max HP at 196 at the rear wheels. Using 12% loss number, it translates into 222 at the flywheel.
Catpipe, Bursch, Weltmeister chip.
BTW, I did this test 5 minutes after weighing the car. So the data was very fresh.

[old_skul]

I wouldn't bother drilling a 3.2 airbox. BA has done dyno testing of cars with the airbox cover and filter *removed*, and wound up with a <1hp gain. Why compromise filtering for a less than 1hp gain?

Chips are nice and all but chip + exhaust is really the way to go. A lot of the chip fuel mappings are optimized for a more free-flowing exhaust. If you're going to do just one, do the exhaust.

[KFC911]

Hi Steve, I've got an '88 3.2, and have replaced the muffler with a stainless GHL 1in/1out, and am going to replace the cat with a Fabspeed euro premuffler. I use 93 octane only (almost always Amoco). I'm interested in a chip upgrade which will increase performance by taking these factors into consideration, and to also increase the rev limit to a higher value while keeping it within a reasonably 'safe' value for the 3.2. Would a chip upgrade be noticable on my "butt-dyno", and would it help across the whole rpm range, or would it be most noticable at high rpms? If anyone else has done similar mods on a 3.2, and could provide feedback, that'd be great. Thanks...Keith

[Steve W]

Keith, with a properly mapped chip, you will notice quite a torque and power increase throughout the range. Not just at full throttle, which is easy for anyone to remap, but reworking the part throttle ranges to produce a very noticeable torque increase in the low and midrange part throttle region where you do most of your driving. This also helps to increase your fuel mileage a bit, as your engine is working more efficiently with the higher octane fuel. Best way to summarize the difference, is that where as the stock chip take a while to respond and just pulls conservatively, a properly remapped chip will make the car seem to leap, and pulls harder all the way to redline as if you had a displacement increase. Without sounding too commercial here on Wayne's board, if you have more questions, just email me stevekw@pacbell.net.

[Wil Ferch]

Hi:
Answers to questions since my last post.....
- I don't know the brand name of my chip ( ! )..it was already installed when I bought the car from the previous owner..the stock chip was found in the glove -box.
- If you drill the box, might as well section it completley to only have the band that surrounds the filter..a la Cup , as someone said. Take off the snorkel too. If nothing else, it allows you to easily attach all 4 clips of the lid, and it greatly improves maintenance access. You retain the box' s internal snorkel, too.
- Weltmeister and slightly more expensice Autothority chips ( $200 to$450 range) should work very well. I've talked to Larry Bershstein of Cyntex directly and he feels that the amount of mods I have are too few and insignificant to warrant a custom chip burn. Personally, I think he is correct but that a *small* amount of tweaking is still possible ..say on a Dyno with your particular car.
- here's a pratical before/after test. A roll-on acceleration test in 3rd gear from 3000-6000 rpm. Stock for 3.2 should be about 10-11 secs. I've seen as low as high 8's in my car. Caution, speeds get to over 90 mph when doing this..use discretion. Also, slight roadway incline and decline makes a BIG difference. Tach swings past 3000 really quick , but passes 6000 really slow...make sure you're not "fudging" the time as it sweeps past 6K...you tend to trip the clock sooner because you "want" it to at 6000. Be consistent.

--Wil Ferch

[KTL]

Mark,

I don't think the filtering is compromised since the box is opened up before the filter element. You're simply letting more air get to the filter element, right? Any air getting into the throttle body is still filtered as originally before the drilling/cutting. My hacked spare box lid looks like this (not as nice of course):



Don't get me wrong. I don't think the airbox mods do anything really noticeable other than making more noise! I just did it because I had this spare lid that was drilled into oblivion:

Swiss Cheese Lid

and figured i'd see how one of the "motorsport" style lids fits in there. Seems to me it'd be pretty easy for some water to get in there with most of the face of the lid missing. I'll stick with my stock box, thank you. Just call me a "Sally" I guess. I like things stock.

[Wil Ferch]

To Jeff Kramer:
Hi Jeff...one more thing that no one has brought up yet...early cars use a 24 pin chip..later 3.2's use a 28 pin chip. Something about a 4K vs 2K Eprom that allows more data to be processed at low rpm for a better idle...no real performance difference due solely to this.
However, wheras some later models of the early cars ( like my 24 pin 1985)...some early 84's had the chip soldered in-place, and not easily removable. Later 24 pin cars used removable chips....caution.

---Wil Ferch

[Wil Ferch]

Sorry..
Last message was interrupted and garbled.

Meant to say some early cars like some 84's used soldered-in chips...later cars, even within the "early" series using 24 pins...had removable chips. The "even later" 28 pin 3.2's used removable chips...

Sorry..

---Wil Ferch

[Bill Verburg]

IMO any mod needs to be considered from a systems approach. there is a synergy from combining ssi, cams, chips for beyond their individual contributions. I would do as much at once(proven mods , not experimental) as I could afford. An off the shelf chip will never be as worthwhile as one custom burned on a dyno.

A set of 964/993 cams, ssi's and chip will really wake a 3.2 up.

[Wil Ferch]

Guys:
I have to agree with Bill V as to the systems approach yielding the most benefit, however, since the baseline for this particular thread is an 84 ( or 85)..cars that were delivered to the US assuming only regular grade fuel ( 87 octane), I believe any good, reputable chip ( Autothority, Weltmeister) would do the trick. I guess given enough time to study the baseline case and mods done to a car, Steve W could likely whip up a chip to match the mod components of the given car...agreed.

---Wil Ferch