ptuomov

Edit: POLL ADDED

The idea would be to get more flow thru, since there will be fender mounted intercoolers. I am trying to come up with a functional mod that is as "quiet" as possible and true to the design style of the 80's. I think this would be right for the period, since 959 had the vents come about middle of the headlights as well. EDIT: pretty close to the 968!

Your thoughts? If you object to the aesthetics, rip me a new one before I rip my car a new one.

Hilton

Strosek make a front bumper like that - in fact theirs has even wider vents.

I believe it can be fitted independently of their widebody bits.

Look for user GlennM's pictures of his '87 strosek

edit: here ya go https://rennlist.com/forums/6180110-post13.html

ptuomov

Thanks. That's close. It's a bit too aggressive for my taste, since the bottom part is concave and the vents are much larger than stock. Ideally, I'd like to simply extend the stock vents some inches to go about middle of the headlight with no other changes. But that Strosek piece is definitely close enough that it warrants consideration.

EDIT: This link has a photo in which Strosek bumper looks pretty good: http://www.motorbase.com/uploads/ccf...1231502110.jpg

ew928

Nice wider smile. Probably won't be noticed to the casual 928 observer till someone points it out.

I don't see an easy way to make the fog/high beam combo light opening slightly larger.
That would vent directly into the front wheelwells.

928autobahndreamer

^agree. I don't think it looks out of place on the 928 and would probably go unnoticed except for true die hard 928 enthusiasts.

ptuomov

Poll added since a lot of people have viewed this thread.

Alan

I think it would look fine - not very noticeable...

However I think it will be very hard to implement that way - You presumably will have to create an all new support mechanism for the dividers - which will need to fabricated from scratch. The stock support mechanism was not great IMHO - many are already damaged - a light front end curb incident often breaks these supports...

Have you considered some kind of simpler corner vent directly into just the fender portion?

Also what provisions do you have for ensuring airflow out (only behind the cooler) since thats also a major contributor to effective airflow.

Alan

ptuomov

Thanks for the comments. I have not at all thought thru the implementation, so points you bring up are very helpful. So far, I've only thought about the looks. I got a new belly pan fastener kit, I'll take a look at what's there when I replace the fasteners.

The intercooler setup is designed by John Kuhn, so it will not come as a surprise that the air flow is throughly considered. The intercooler faces the spinning tire. The moving tire has air spinning fast with it, creating a significant vacuum. This vacuum sucks air, and the easiest way it's going to get it is thru the intercooler. Thus, at high speeds, there will be a positive gauge pressure zone in front of the intercooler (ram effect) and a negative gauge pressure zone behind the intercooler. As a bonus, the radiator and air intake air flow is left undisturbed.

See the photo in the link:

Alan

So couple of items - there is no splash shield on Johns car - you no doubt have one. I would not drive a car without some cover over that intercooler for fear of road debris damaging (or clogging it). Seems a louvered cover would work well here with minimal airflow restriction. I'd also want to ensure the area around the intercoler was sealed - else the air will prefer the lower restiction bypass path around the cooler - especially with the headlights down there is good reason for air diversion - a louvered cover sealed to the intercoler could solve this issue too.. Any airpath below the cooler e.g. brake cooling ducts should also be seperated.

I'm not sure I buy the vacuum created by the rotating tire to be a huge effect - but clearly there needs to be an opening to the wheel well. Seems the car should have wheel well liners if its for street use...

Does this modification also require deletion of ABS? looks like possible clearance isues there...

Alan

ptuomov

All valid concerns. Most of your questions I can't answer right now.

I just linked to a particular car at pelicanparts. I don't know who's car that is or what purpose it was built for. I know it's JK's intercooler setup, though, and if it was done by JK I would venture a guess that it is well thought out for the purpose that the car is used for.

The ABS stays.

I was under the impression that the low pressure zone in front of the tire is significant. I'll try to get some measurements with a silicon hose and manometer. It'll look stupid going 80 mph on route 2, but I am used to people laughing at me on a regular basis! ;-)

Widening the vents in the bumper covers would also mean installing vertical vanes behind it to guide air flow. These vanes will kill two birds with two vanes, namely strengthening the bumper cover and guiding air.

Big believer in well planned shrouding. Planning shrouding well is not easy, though.

There's clearly a lot for me to think about with these air paths, this thread was just about the aesthetics and very high-level design. I'll think about this a bit and if the doctored picture grows on me, then I'll start worrying about implementation. Or worrying about who I will be paying for worrying about the implementation.

Ketchmi

The driver's side has an external engine oil cooler and an additional transmission cooler with a thermostatic fan, the passenger's side has the intercooler heat exchanger with a ignition fan. I used expanded stainless for the grille and guards in the wheelwells and a black beading around the opening, looks very similar to older twin turbo ducts. They are sealed and work exceptionally well. This is the 630ish rwhp 89' auto that I built for a customer but we now own. We did find the limits of a stock auto transmission...

morganabowen

That looks really effective. Are you getting the results that you expected???

ptuomov

Your solution is undoubtedly very effective. However, I think it deviates slightly too much from the stock look for my taste.

9x8

That Strosek front bumper piece looks totally awesome, and, IMO, its the best looking body kit available for 928. Unfortunately, that certain bumber is NLA, they only offer "ultra" one now, which differs grealy from stock:

Ispeed

Isn't your car black? You could get away with more and it would be less noticeable.

p.s. I think you should just do exhaust, intake and sharktune, and leave the heavy mods for wheels/tires and suspension. And then drive it a lot.