LDH17

Hi everyone,
I've been reading this forum for a couple of years...finally got the P-car yesterday!
88 coupe,
I can't believe I waited half my life to get myself behind the wheel of a 911!

my coupe has no rear wing, and no front spoiler. I really like the look of the front spoiler, and no rear wing. I remember a thread discussing this issue a while back , but I can't find it. can anyone tell me what the conclusion was? can i run with just the front?

Thanks!

Jay H

Most likely, at normal speeds, you won't notice much difference with a front spoiler and no rear spoiler.

However, the car needs both front and rear spoilers to be balanced in feel at higher speeds (such as stuff over 70-80 mph). Paul Frere's book "Porsche 911 Story" has extensive documentation as to how spoilers affect handling and aerodynamics on a 911. Porsche never equipped 911's with just one spoiler from the factory.

I'd run either no spoilers or both. Not one only.

Hope this helps.

Jay

LDH17

Thanks Jay-
It seems to me that I remember what you are saying was the general conclusion.
I'll keep things just the way they are,...no front , no rear!

2002M3Drew

The front ads front downforce. The rear is meant to add rear downforce. Running the front alone makes the back end of the car feel very light, lighter than without any spoilers at all. I ran mine that way for a while, and frankly, it scared the bejesus out of me a few times on the highway and on the track. With the rear wing, the hand of God is on the car!

Jay H

In the past there have been people posting that "My car came with only a front spoiler from the factory". Regarding the cars from the '80's, I've tended to believe these were dealer installed front spoilers since I've never seen an option code for just a front or just a rear spoiler from Porsche. In my factory documentation it's always listed as Front and Rear spoilers...

BMWDavid

When I first started looking for my 911 I was pretty much in favor of trying to get a car without the sploilers. Of course this eliminated quite a few cars as most have the spoiler option. I did like the clean look without spoilers.

But the more I looked at cars and of course with my '89 Carrera I now like the look. I do understand now that the cars feel better at highway speeds with the spoilers.

But when I do see a 911 w/o spoilers it does look clean.

David

LDH17

Are you saying that at highway speed, 80mph, the car w/o feels unstable , or just less so than are car with the front spoiler and rear wing. I guess what I'm asking is what exactly happens above 80 on the naked 911?

Jay H

On the cars that are 'clean' or without spoilers, the car feels pretty good at speeds above 80 mph. However, if you add the front and rear spoilers, the cars feels a bunch more planted or stable as speeds increase. That's not to say that a clean car is a poor handling car at speed, but you can really tell the difference on a car with spoilers verses without spoilers. If you watch any type of club racing, most of these guys are using the appropriate spoilers. It really makes a difference at higher speeds.

With my '84, I don't exceed 80 mph all that often since it's a daily driver type car, so I'm not running out and getting a set of spoilers just yet... What I'm saying is that for normal street driving at less than excessive speeds, either a clean car or one with spoilers is going to drive pretty similar.

ked

"what exactly happens above 80 on the naked 911?" that's a private matter...
however, I've found that a non-spoilered 911 w/ proper susp settings & components accelerates more quickly, reaches top speed sooner (& also a tiny bit higher?) than the bespoilered variant (even more so compared to a wide-body). it's different, it isn't as planted (revealed in hi-speed sweepers), but that's managable - a lightweight, "naked" 911 rewards talented driving & just flys.

stormmaster

by the way....neither front nor rear spoilers were intended nor do they add "downforce"....they were designed to reduce lift at both ends due to the shape of the vehicle....

madmmac

A front with no tail is fine...a tail with no front is not fine.

LDH17

madmmac,
I might tend to agree with you . there are a lot of sports cars out there that have a front spoiler but no rear spoiler of any sort. However, they don't have the unique shape of the 911. most have some kind of squared-off trunk or something.
Can any of the club racers add their experience to the mix here?

vanwyk4257

A couple things from my perspective. I had a '75 911 with no spoilers and then added a front spoiler. I didn't really notice much difference on the street or even at highway speeds up to 80mph. Then I bolted a turbo tail on just for giggles and drove it and I couldn't believe how much more planted the car felt. I now have an 85 Carrera with front and rear spoilers and it feels the same way, very nicely planted at 80mph.
Also, the front and rear spoilers don't really add downforce as someone indicated earlier, they really just reduce the lift that the 911's shape tends to otherwise generate.

ked

let's see... a spoilered (both f&r) 911 has less frt & rear lift and overall, the lift is balanced... so, if one has only the frt spoiler, then it has less lift at the frt only... meaning it has (relatively analyzing) more rear lift - lift is unbalanced and rear biased. hmmm, I don't know about anyone else, but I do not want (again, relatively) unbalanced lift & more of it on the rear when going through a high speed (90+mph) decreasing radius sweeper... someone else is welcome to do the empirical research.

one minor setting that is suprisingly noticeable & beneficial on non-spoilered 911s is to be sure the chassis ride height setting achieves a one degree nose-down slope. I'm sure this is also the case w/ spoilered 911s, just that the non-spoilered 911 is more sensitive to "angle of attack" since it has more lift to manage. think of the whole body as an aero device, so frt / rear ride height is one of the few aero-adjustments one can make. also, don't overlook the impact of tire width on drag. has anyone measured the influence of the mirror positions on top speed or accel?

Jay H

Ked's right on the money with the nose down stance on a non spoilered 911. My trusted mechanic immediately dropped the front of my '84 (non spoilered 911) when he got his hands on it to tweek it (he loves messing with the older 911's) after I bought it. It definitely made a difference to me at decent freeway speeds with the nose dropped ever so slightly. I've got pics if anyone wants to see the before and after looks.

Porsche is a pretty sharp company that knows how to engineer cars properly. I'd still either have either no spoilers or both front and rear...