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-   -   Gain 100HP with an intake manifold change?? - Cross post from Ferrari Chat (https://rennlist.com/forums/928-forum/922127-gain-100hp-with-an-intake-manifold-change-cross-post-from-ferrari-chat.html)

hans14914 03-09-2016 05:07 PM

Shameless bump:

https://rennlist.com/forums/928-foru...4-intakes.html

Intake design is not that hard for a 928. Plenty of space... its just trying to get enough people together who want to pay for it. Took me years to just get enough people together to do a run of flanges.

mark kibort 03-09-2016 05:07 PM

2 Attachment(s)
Im willing to bet, this is the answer

since greg doesnt want to partake, and carl already has the foundation, I can see a version of his design that maybe uses a EURO 2 valve U , with throttle body and the maf attachment pont that would feed right into the stock air box. there is lots of room in the "valley" of the 928 engine block, so isnt this a possibility?

more info on his intake development

http://www.928motorsports.com/instal...oldarticle.pdf

the entire idea i have here is to make it near plug and play. the stock throttle body mechanisms mount to the side of this thing, as do the vacuum lines etc.
stock MAF, and maybe a way to use the euro 2 valve U and some after market throttle body, although i think the 3.5 " euro TB should be adequate, unless the 85 us TB is better.

mark kibort 03-09-2016 05:16 PM


Originally Posted by Mongo (Post 13092167)
You definitely need to read good books on volumetric efficiency, runner length and flow when it comes to the construction of an intake.

By no means am I an expert in this, but I do believe runner length and tapering may have a lot to do with how Greg was able to create the gains he did with his setup. Hell, with any setup this is imperative to have knowledge on.

im not doubting this, but certainly with anything opening up the intake , we will se big gains.. sure, if the runners are too short, its going to be a high strung motor, but i think the gains willl more than offset the losses. however, to your point, i would rather see an intake that more mirrors what the aston Martin has done. if these runners could cross over to the other sides , i think that might solve a big torque issue that would be present with the non boosted use of Carls design.
again, im no expert either, but you can see what the other manufacturers desingns have brought as far as power to some small street type engines, making 330rwhp, out of 4.3 liters and near 440rwhp out of 5 liters.
we dont need to match the gains in all areas, but its a good sign that we can approach those gains . heck, even 50% of those gains would be worth it , if most of it is coming from the intake, which it is.

Imo000 03-09-2016 05:29 PM

Stop using "We", you are not the representative of all of us.

Mongo 03-09-2016 05:35 PM

How about "WE" all cobble our heads together to create a feat of engineering using the wealth of knowledge many have on the boards, even if it is the most miniscule.

Leave the bickering in the HS girl's bathroom about what tampon is better.

mark kibort 03-09-2016 05:39 PM


Originally Posted by Imo000 (Post 13092250)
Stop using "We", you are not the representative of all of us.

would you just please STFU.. what are you, 7???? dont try and and be a tough guy internet bully... it doesnt work with me you pipsqueak!
read mongo below... he describes you perfectly...... "i want the one with the wings" you say?? ;)


Originally Posted by Mongo (Post 13092271)
How about "WE" all cobble our heads together to create a feat of engineering using the wealth of knowledge many have on the boards, even if it is the most miniscule.

Leave the bickering in the HS girl's bathroom about what tampon is better.

thank you ! agreed!

Mongo 03-09-2016 05:43 PM

Here is a sample of a sectioned intake manifold by FAST for LS applications. I think something similar can be done with the 928..

http://images.machinedesign.com/imag...0000037524.jpg




Here is the link to the article providing the pic.

http://machinedesign.com/archive/com...ne-performance

James Bailey 03-09-2016 05:46 PM


Originally Posted by hans14914 (Post 13092182)
Shameless bump:

https://rennlist.com/forums/928-foru...4-intakes.html

Intake design is not that hard for a 928. Plenty of space... its just trying to get enough people together who want to pay for it. Took me years to just get enough people together to do a run of flanges.

Hans what is a reasonable estimate of the cost of the flanges today ? I recognize that the first batch ended up costing you a lot of money. Just trying to inject a bit of reality to this just cobble together a bit of this and that should maybe cost $2,000-$3,000 all in all done. I believe Carl sells his composite flanges for $1925-4,295 depending on if fiberglass or carbon filled.
Yours are truly works of art !! Like most fabrication once it IS DONE it looks so simple and easy...... :) very nice.

Mongo 03-09-2016 05:48 PM

Another great pic... this is the cutaway of an intake manifold on an Aston Martin V8 Vantage.

Take careful notice of the tapering of each runner.

http://www.6speedonline.com/forums/a...ine=1374173674

James Bailey 03-09-2016 06:00 PM

note how the rectangular shape twists 90 degrees from the top to the bottom wonder what the port shape and size is ?? Quite a nice piece of work there....and very short pistons for lightweight. No wonder it can spin up so well. I rather enjoyed driving it but never really punched it hard.

V2Rocket 03-09-2016 06:07 PM


Originally Posted by mark kibort (Post 13092183)
the entire idea i have here is to make it near plug and play. the stock throttle body mechanisms mount to the side of this thing, as do the vacuum lines etc.
stock MAF, and maybe a way to use the euro 2 valve U and some after market throttle body, although i think the 3.5 " euro TB should be adequate, unless the 85 us TB is better.

howabout 2 plenums with a balancing port, and a 944TB (55mm) on each?
the key is equalizing (or as close as you can) runner length so they all tune to your high RPM target, for peak power gains.
S4 has a mix of long and short runners to broaden the curve...
find the RPM your cams make peak power, and set runner length accordingly.

GregBBRD 03-09-2016 06:13 PM

As a point of order, in another thread where Kibort (the consummate expert on all things 928) appears to be running amuck.

Again.

Apparently, from what I can gather, Kibort is altering what I said about an intake system being both difficult and expensive to produce into me not building one, at all.

Nothing is farther from the truth.

I am full scale production, with Hans's extremely skilled help (and patience), and fully intend to have a production version of my prototype intake, which I tested on a 6.5 liter and a 5.0 liter 928 engine making impressive power output gains ready for use by summertime.

This intake will have runner sizes and plenum volumes that should make it suitable for both 5.0 and 5.4 engines in stock form, as well as high performance applications.

Earlier in this thread, I made a post about this being an expensive undertaking. That is still true. I'm going to have a huge amount of time and money invested (50K?) in this effort. I've got 3 or 4 people that will buy a manifold, for sure (none of those people are Kibort, BTW.)

Not exactly a sound financial basis....

So, the point I was making still remains....this will be an incredibly difficult effort to ever break financially even on.....for the tiny 928 market.

Regardless, I need this manifold for my own purposes, which is why I chose to continue with this development.

Mongo 03-09-2016 06:21 PM

Any luck for sourcing a company to do injection molds and a jig/template? I remember you said it was very costly, but at least if the demand is HOPEFULLY there, a polymer version can be available for street operated cars.

mark kibort 03-09-2016 06:48 PM

thats exactly my point... its not worth your time... (your words), and those words confirmed below. never said you didnt build one.. quite the contrary... you have one on the stroker and i would LOVE to see that made again, even if done with lower cost techniques. you didnt say( or maybe i didnt see this) that you were in full scale production! :)

so to help us (928ers) out, what do you think is the best way to get an intake on the 928S4? lets not make this personal.. its just a question? can we use /buy your technology to get this done?

by the way... did my words hurt you? i have no beef with you Greg.. I would always be willing to buy that intake if you wanted to sell me one, with no strings attached. dont go School-Girl on me. you know i would get the best use out of it too! :)


Originally Posted by GregBBRD (Post 13092405)
As a point of order, in another thread where Kibort (the consummate expert on all things 928) appears to be running amuck.

Again.

Apparently, from what I can gather, Kibort is altering what I said about an intake system being both difficult and expensive to produce into me not building one, at all.

Nothing is farther from the truth.

I am full scale production, with Hans's extremely skilled help (and patience), and fully intend to have a production version of my prototype intake, which I tested on a 6.5 liter and a 5.0 liter 928 engine making impressive power output gains ready for use by summertime.

This intake will have runner sizes and plenum volumes that should make it suitable for both 5.0 and 5.4 engines in stock form, as well as high performance applications.

Earlier in this thread, I made a post about this being an expensive undertaking. That is still true. I'm going to have a huge amount of time and money invested (50K?) in this effort. I've got 3 or 4 people that will buy a manifold, for sure (none of those people are Kibort, BTW.)

Not exactly a sound financial basis....

So, the point I was making still remains....this will be an incredibly difficult effort to ever break financially even on.....for the tiny 928 market.

Regardless, I need this manifold for my own purposes, which is why I chose to continue with this development.


mark kibort 03-09-2016 06:59 PM

6 Attachment(s)

Originally Posted by James Bailey (Post 13092359)
note how the rectangular shape twists 90 degrees from the top to the bottom wonder what the port shape and size is ?? Quite a nice piece of work there....and very short pistons for lightweight. No wonder it can spin up so well. I rather enjoyed driving it but never really punched it hard.

They look like ford heads in person . its a bore and stroke that is not far off our engines. it really doesnt "spin up " that well (your imagination).. RPM doesnt fall very fast at all, pointing to high rotating mass. ive beat the thing on the track for many laps.. the big flywheel and US mustang style clutch , and rotating mass dosnt help things much. it twists up to 7800rpm easily, but there is no torque down low at all.

the vantage doesnt have the cool pistons of the model...they look as ive captured below. stuff looks like stock porsche stuff. and the familiar girtle of how the crank bolts in...very 928ish

maybe the model was a new version of the V8 vantage engine, but it certainly is not the one you or i have driven. (you with your daughters 4.3 liter 2006-7)

also Jim, the vantage is like a stroker stroke! 91mm stroke!! (91mm bore) on the 4.7L, BUT, your daughters is a 89mm bore with a 86mm stroke... still near stroker rod angles!! not a high rever like ours can be !


Originally Posted by V2Rocket (Post 13092378)
howabout 2 plenums with a balancing port, and a 944TB (55mm) on each?
the key is equalizing (or as close as you can) runner length so they all tune to your high RPM target, for peak power gains.
S4 has a mix of long and short runners to broaden the curve...
find the RPM your cams make peak power, and set runner length accordingly.

i think that would be great, but i do like the idea of keeping it simple by using a single large throttle body. just be easier to retrofit and make this a plug and play product. I think what mark and Joe had with the CF intake was pretty good. it was a bolt on 100hp. im sure with an S4 it would be a bolt on 50hp adder!


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