merchauser

I have been reading, with great interest, the variety of custom intakes being manufactured or proposed.
they are all very interesting, and fascinating in their craftsmanship and technology. its great to see all of
the interest in advancing and reengineering key components to make these cars better, faster, and even more fun.

I have great appreciation and respect for all of those making these advancements, but clearly they are more for the serious
mod guys with strokers, and/or larger pistons, valves, etc. my interests are a bit more humble, and would like to know
if others out there interested in this type of intake?

I would be interested in an OEM intake, internally modified for better flow and power gain. I'd be willing to go with larger
injectors and/or throttle body, and headers with a free flow exhaust, that a better flowing intake might require.

anyone working on this type of intake??

SwayBar

I know there are several in the works, but do not know if any are for the masses. In other words they might be one-offs.

V2Rocket

maybe they'll make another one of this "one-off" if you call them with $$ in hand.
https://rennlist.com/forums/928-foru...2v-intake.html

The Forgotten On

You can extrude hone the stock intake and get a fair bit more HP and TQ from just that and gasket matching the intake.

Fairly standard stuff and it works well.

Carl @ 928 Motorsports did this to an intake along with adding an adapter for an LS throttlebody and got 50 HP on an otherwise stock engine.

There is a thread for it somewhere...

Koenig-Specials 928

Then you need to contact one of our resident experts Greg and possibly join a line I am sure.

https://rennlist.com/forums/928-forum/752075-do-these-pictures-need-captions-32v-intake-manifold-study-hp.html

hacker-pschorr

That was tested on a 6.54 liter engine, far from stock.

merchauser

I asked Carl about that intake and he candidly told me this was not for a stock set up.

would like to hear more about this procedure.....

Koenig-Specials 928

Why bother?
Just call Greg and give him all your Christmas $$$.
Look at that picture again. That's just beautiful and functional as are all his products.

just saying!

hacker-pschorr

Give these guys a call (first it on a google search):
http://www.extrudehoneafm.com/

There was more to that intake "The Forgotten On" didn't mention either.
The lower "shoe" section was also replaced, MAF eliminated, larger throttle body, and different fuel injection system (The "easiest" way to go would be the Shark Tuner Alpha-N @ $450. This assumes you already have access to a loaner Shark Tuner).
Now figure 1-2 hours on the dyno tuning it in will be another $300.
All in you'll be looking at about $2,500+ to replicate that intake just to find out what it will do on an otherwise stock engine.

That's the problem, cost benefit ratio. I was talking to a long time 928 owner the other night, and we were discussing Greg's intake. A prototype designed for a stroker they popped on Jim Coreman's GT just to see what would happen. The results surprised most people I think (photo above).
Results in this post:
https://rennlist.com/forums/928-foru...l#post10867655

+39.49hp
+22.75tq

We tossed around hypothetical guesses as to what a developed intake would cost....
M friend said: "Who would pay that much for 40hp?"
I said: "Me and a lot of other people I'm sure"......and that's the problem. Someone has to spend a serious amount of money to develop & test a prototype with the "hope" a couple people will buy it.

Looking up intake manifolds for Ford's and Chevy's that cost $1,000, I figure multiply that by 2.5 at the minimum to bring such an intake to market for the 928. Is there a market for a $2,500+ bolt on option? That's the question people have been asking for many years.
The cost of the intake is step one, now you have to develop Shark Tuner chips or require each one to be individually tuned by the buyer. The Ford & Chevy guys can go to any tuning shop since the software is so generic, we do not have that luxury.

How much power will be expected on a bone stock 87 automatic to justify the cost? The test of Greg's intake was on a 5-speed GT and I do not recall if it has headers & full exhaust work or not. That intake on a stock S4 automatic could very well yield much less results. Yes I know you have a GT, but developing an intake just for the GT would be even less cost effective.

I'm not trying to be a Debbie Downer here, I've been working with Twin Turbo Todd on a custom 16V intake for a couple of years now and I was somewhat involved (fly on the wall) when he designed and built his intake.

Todd and I were tentatively drawing up a 32V intake when I bought my S4 a couple of years ago. He has a few ideas in mind and already has the S4 data configured in his tuning software.

Once Greg & Jim posted the above information, Todd and I discussed it and agreed further work on our intake would be better spent doing something else, just wait and see what Greg does.

In my opinion the best thing to do would be:

1. Contact Greg to see how development work is taking place on the intake above for a 5-liter. It would really help if someone handed over a wad of development cash.........
2. Contact Carl to make a 5-liter version of the 6.54 intake

A third option is to pick a shop like this:
http://www.weinlemotorsports.com/Cus...take-Manifolds
And start having your own custom intake made.

What have you done to the GT already? Step one would be headers, exhaust and a tune. I've seen anywhere from 320 - 330rwhp with that setup on a GT. IIRC John Speak has a nice upgraded tune available for GT's.

If you have the stock exhaust, I would be on the phone with Greg to see the availability of his headers & exhaust. As far as I'm aware it's the most complete and highest performing "bolt on" exhaust system for the 32V cars:
https://rennlist.com/forums/928-foru...no-charts.html

merchauser

Erik,
thanks for the detailed response. I finally have a grasp on what its all about and the costs associated.
for my application, I am beginning to realize that I should travel down a different road; and that's all good.
the car is a lot of fun, and I truly have nothing to whine about.

car is currently bone stock. new hall sensor made a HUGE difference in the car. next plan is cat
delete and X pipe. I have spoken to john speake about his GT chip, he honestly told me that sharktuner
was really for more modified sets ups and thought the chip was a good solution.

Headers???? reading so many different posts about headers. it appears consensus is that headers
do not provide that much of a gain compared to X pipe add on? is that correct or am I not reading properly?
I have installed headers in other cars with great results, but in tandem I installed complete exhaust systems
so I can't pinpoint which component yielded the best gain.

jcorenman

Yes. Devek L2 headers, full 2.5" exhaust (Louie Ott's effort for the PO), bigger cams.

Not correct. There are many reports of fitting x-pipes with good results. But remember that the x-pipe also replaces 20-30 year-old factory cats with either a "test pipe" or hi-flow aftermarket cats. How much of any gain is the crossover versus fresh hi-flow cats (or no cats)? Proper headers, combined with a 2.5" exhaust and hi-flow cats, certainly produce more power.

The problem with the "how much" question (both power and cost) is that Porsche generally did a very nice job of "balancing" the design. By that I mean that the intake, cams, exhaust were all designed around a pretty conservative power level, and changing just one thing is generally disappointing. One exception is cams, the GT cams are much better than S4 so that is an easy (but not particularly cheap) first step for an S4. But your GT is there already.

Exhaust would be the next limitation, and I think Greg's headers and exhaust is the best option available. A close second would be to find a set of Devek L2 headers combined with a fabricated 2.5" exhaust, and get a Sharktuner and do some serious tuning. Then maybe bigger cams. This is where our GT was at when we did that test of Greg's intake, and I think we were just beginning to see the limitations of the stock intake.

That engine is now 5.9L (same cams and exhaust, ported stock intake) and we are definitely intake limited. But for a 5.0L engine I think spending any effort on the intake is farther down the list than cams and exhaust and tuning.

hacker-pschorr

A lot of variables to that question.

1. Define "that much". To some people 5-10hp is a good gain. It's an odd baseline since the 16V cars it's a huge upgrade because the stock exhaust is horrible. Installing 85/86 manifolds on a 16V car is also a nice upgrade. The S4 manifolds are the same as the 85/86 so they are already a step ahead.
2. Many headers were installed pre-shark tuner or not shark tuned even after.
3. Anyone who installs headers then has the car tuned, did they first tune the car to it's full extent? If not the before / after isn't 100% accurate.
4. Few "bolt on" options for a full exhaust after the headers have existed over the years. Greg's is the most complete I can recall
5. How does a full header exhaust compare to stock with X-pipe? Again, big costs for someone to answer that question....

I would love to have all the parts supplied, I'll do the labor & even pay for the dyno time with our guru Luke (who co-tuned Turbo Todd's car) at Beyond Redline...... I already have an x-pipe.......

Back to Greg's exhaust. I do not recall such a before / after test on an S4 / GT, but here are the results on an 85/86:
https://rennlist.com/forums/928-foru...l#post11484991

Pretty impressive if you ask me....

Since most conversations turn into dyno shenanigans, here is a data point of Shane Elliots 85.6 showing a before dyno damn close to Greg's above:
https://rennlist.com/forums/928-foru...s-new-car.html


I've seen multiple reports over the years of 320-330rwhp for a GT with headers, exhaust, and tune. The "best" headers IMO before Greg's were available are Devek L2's. Which explains why AO recently sold a set for $1,750.

Walt L

Custom intakes!?!?
What custom intakes???

GregBBRD

There's also a before/after dyno on a stock GTS somewhere on this Forum. This was done on William Anast's beautiful GTS....I'll try and figure out how to find and post this...my computer and social skills are very limited.

I will be building two different intake systems. One for large displacement S4 engines and one for smaller displacement S4 engines. The large displacement version is coming along. It is very expensive and time consuming to go from a hand made prototype to having multiple intakes for engines....so it proceeds slowly.

There's quite a bit of internal debate about this large displacement intake every being offered as a "general public release" product or if it will only be offered an option to existing client's engines and internally built engines.

There are currently SEVERAL products that I make which are not offered for "public use", but only find "homes" on my own engines, so this is likely to be the case. For instance, my new ventilation system for the S3 engine is now completed and long term testing is underway. Short term testing shows ZERO oil making it to the plenums, even on Van's stroker engine that now has over 500 miles on it....that has been driven aggressively to test and tune. Because I'm sick of people copying my products. It is very doubtful that this V3 ventilation system will ever be "released" and will most likely remain an internal product. (You guys with S3 intake plenums FILLED with oil can thank the people that steal and copy ideas! I'm completely done making trick stuff that people "steal" the technology for and make on their own.)

Regardless of what the future holds for many of my products, it will be very doubtful that a replacement intake on a stock S4 engine will ever be the first step towards getting more power....the first "restriction" to improve on is the exhaust.

hacker-pschorr

I thought so, but I couldn't find it either. Do you recall who started the thread???