jthwan22

According to this link he took the whole nose off. Are you saying that is not needed? If I remove the flap should I also take out the shroud?

https://rennlist.com/forums/928-foru...-question.html

H2

Ken,

The S4 still runs too warm when pushed hard. It's my daily driver and works fine for that. However, I can't take it to the track until I figure this out. The problem is not in the usual list of things suggested here in Rennlist (Search may be my friend but the answer is still elusive). Louie gave me some other ideas that I'll check out once the weather warms up a bit. They're predicting 17 degrees (F) this weekend. That's more than my garage heater can deal with.

Harvey

Rob Edwards

You don't HAVE to take the nose off- it would be pretty easy to just reach in and either break off the flaps or use a hacksaw blade and cut them out of the frame. I just wanted to see if it could be done non-destructively. I think you should definitely keep the shroud- there's a reason they went to the trouble of ducting the air towards the radiator, and put those vertical slats at the rear edge of the radiator to force airflow thru the rad.

Richard S

Here's how Tony did it without removing the whole nose...I followed his lead and did it the same way. https://rennlist.com/forums/928-foru...s-removal.html

Rich

H2

Rob,

What you mention about ducting air towards the radiator...makes me think that the flaps probably result in BETTER cooling...rather that what some think. Obviously, if the flaps do not open, it would result in must reduced cooling.

Harvey

Louie928

I think you have a valid point, Harvey. With the flaps open there is minimal obstruction and they provide a directional component to direct the air slightly upward toward the center of the radiator rather than dumping it in at the bottom.

mcholdfast

Now that you mention it, the 89 GT is the only one of mine that is missing the flaps and it runs noticeably hotter than the other three.

Rob Edwards

Hmm-

Good point, guys, but didn't they do away with the flaps in '91? Was there a concomitant change in the ducting in '91? Perhaps I'll have to append the Flapectomy to a Flap R&R.....

Louie928

Yes, the flaps disappeared in '91. My '91GT doesn't have them and the ducting looks the same as on the '90. Were the flaps eliminated to improve cooling, or to cut cost? The fate of the 928 was already being written by '91 so my bet is that it was an easy to do cost cutting project. I wish someone who did the flapectomy also had good before and after data to support one position or the other. Pun intended, heh, heh. I took them out of my '90, but for other reasons.

H2

Mike,

Doncha think the '89 GT runs hotter because it's a "hotter car" to begin with?"

BTW, look at Louie's rear tires (in his avatar) and I think you'll get some idea of why he might have removed his flaps. In order to spin his tires at will at about any speed (dry pavement too), just by stomping the gas, he had to put considerably more horses under the hood area. Interestingly, he runs cool anyway.

H2

Louie928

It runs cool enough on the track. On a hot day and going up a good hill it gets about as hot as I want it to on both coolant and oil temps. Coolant at the top white line and oil temp about 235F. By good hill, I mean something like on I-84 Cabbage Hill East of Pendleton into the Blue Mtns on a 100F day. That's around 4000' elevation change in 12 miles and going as fast as I dare around the curves to keep Chris from screaming.

the flyin' scotsman

All true Dr. Bob except we don't drive (at least I don't) our 928s in the winter....................with windchill its only -36C today.

Harvey................I removed the flaps and motor:

1) one less failure point to be concerned with

2) it was deleted in future MYs and I would have thought Porsche would have considered all consequences.

If you want they're in the frozen quonset; I could rescue them in.........March?

fraggle

I have what's left of my S4 shrouds and fan if you still need them.

mcholdfast

Could be but the difference is significant. Then again, it could just be the temp gauge. Maybe Santa will bring me an IR thermometer so I can check its accuracy.