| Author | Message | ||
| V.Z. (Ama328)
Junior Member Username: Ama328 Post Number: 247 Registered: 11-2002 |
wouldn't be too hard to test, by doing some back to back runs with & without the spoiler... | ||
| Dr Tommy Cosgrove (Vwalfa4re)
Intermediate Member Username: Vwalfa4re Post Number: 1268 Registered: 5-2001 |
That's funny about the temp gauge confusion. I have done the same type of thing before. Weird, isn't it? I have still not put the oil cooler fan on yet like I said I was earlier this summer. I have gotten it planned and have a guy waiting to get it on but just too many other things have been going on. As soon as it is on and tested I will post the details and results. | ||
| Mike Charness (Mcharness)
Member Username: Mcharness Post Number: 924 Registered: 8-2002 |
Tommy -- how could I have had it wrong on these years? I was thinking the water temp was on the center console... this thread made me re-look at the manual, and I see that's the oil temp. It's my oil temp that goes to around the 3/4-7/8 mark at the track! Like yours, my water temp stays pretty stable. Duh... But my new Hayden fans may reduce the water temp to the point where it helps reduce engine and oil temp as well. | ||
| Mitch Alsup (Mitch_alsup)
Member Username: Mitch_alsup Post Number: 984 Registered: 4-2002 |
"I can tell you it does NOT help cool the engine bay. Period." To be precise, and in accord with my previous post: The amount of cooling this device can provide to the engine bay is on-the-order of 2-3 degrees while cruising at (say) 60 MPH, and might cut drag to allow another 2-3 MPH (160->163). This is easily small enough that even an attentive owner could not tell without more precise measurement equiptment (than comes int he car). | ||
| Barry Wolinsky (308gtb)
Member Username: 308gtb Post Number: 631 Registered: 2-2002 |
Tommy, The Studio Aerodinamica wound up in Ferrari's back lot several years later. Too bad. I would have gladly taken it!  Barry | ||
| dave handa (Davehanda)
Intermediate Member Username: Davehanda Post Number: 1695 Registered: 5-2001 |
Mike, the oil temp sender screws into the forward/front side of the oil sump. Easy to find once you lift the rear. Single wire plugged into it... Sounds like Tommy needs a bigger oil cooler and a thermostat so it doesn't get too cold during normal street driving. | ||
| David Feinberg (Fastradio2)
Member Username: Fastradio2 Post Number: 287 Registered: 4-2002 |
Dr. Tommy, I've been trying to get in touch with you for a few weeks now...Kindly drop me a note at your first opportunity. I need that tool back... Thanks, David | ||
| Dr Tommy Cosgrove (Vwalfa4re)
Intermediate Member Username: Vwalfa4re Post Number: 1265 Registered: 5-2001 |
I swapped my sending unit last spring hoping to solve the hot oil temp thing. It didn't work. The temps were still sending the needle all the way right (on the track only). Interestingly, no matter how hot the oil gets on the track, the water never passes the half way point. The way to keep my water temp down is to drive the wheels off of it. The faster you go the cooler it gets. Now the oil temp is a totally different story under the same conditions. It cools fast, though, when you pull in the pits. I tried to get a shot of the temp gauge at the last Barber's event to post here just to show everybody HOW hot but by the time I got parked and grabbed the camera, the temp dropped 20 degrees. Anyway I doubt a new sending unit will "cure" anyone's problem since it didn't fix mine (unless your sending unit really is shot) | ||
| Mike Charness (Mcharness)
Member Username: Mcharness Post Number: 922 Registered: 8-2002 |
Dave, where does the oil sender reside? I don't have that problem, but am just curious. | ||
| dave handa (Davehanda)
Intermediate Member Username: Davehanda Post Number: 1694 Registered: 5-2001 |
High oil temps are likely to be the sender, this happened on my 308. Water temp was normal, but suddenly the oil started reading 20 degrees higher...new Veglia sender, all is well. Only $14. | ||
| Mike Charness (Mcharness)
Member Username: Mcharness Post Number: 916 Registered: 8-2002 |
Hey, Tommy, maybe our QVs would be even HOTTER without that basket handle spoiler. Hard to tell. But you're talking about the heat in TRAFFIC, anyway... if the spoiler did create some kind of improved air flow, you'd only get benefit from it at high speeds. I've recently bought high air volume Hayden fans that I'm going to have put on before our next track event. But my car doesn't have the oil temp problem yours does... it's my water temp that's more of a problem. Of course, for all I know, it's just a sending unit problem, not really a temperature problem. | ||
| Dr Tommy Cosgrove (Vwalfa4re)
Intermediate Member Username: Vwalfa4re Post Number: 1263 Registered: 5-2001 |
By the way, that car Barry posted is the one I was referring to. | ||
| Dr Tommy Cosgrove (Vwalfa4re)
Intermediate Member Username: Vwalfa4re Post Number: 1262 Registered: 5-2001 |
I can tell you it does NOT help cool the engine bay. Period. The thing was first put on in 1983 on the QV's. This site is full of threads addressing the hot-running injected 308's. Some owners say their car runs a steady 195 all day long, others (like myself) see the temp shoot up on a hot day in traffic. I have done everything, and I mean EVERYTHING, and the damn temp still seems too hot on certain occasions. Not always, just on a really hot day. Anyway, I never hear this out of the guys with the carb 308's. Thinking back on it now I am not so sure that too many 2V owners complain of this (although I could be wrong). What I do know is the 4V cars seem to be the hottest running ones and those were the only ones the factory put the spoiler on. I am convienced it is nothing more then a cosmetic add on. I do know it absolutely doesn't help the cooling and the top speed and mpg ain't that different then any other US spec. 308 ever made, including the carbs. At least not different enough to show up on any road test published since 1975. The top speed and mpg on these cars are directly related to the engine power, trans ratios, etc. Not a spoiler. I like the looks without it and really the only reason I haven't removed mine yet is because it will expose the mounting holes and I may as well wait till it's next paint job. | ||
| Tillman Strahan (Tillman)
Member Username: Tillman Post Number: 881 Registered: 11-2001 |
Hmmm. Lots to think about here. Thanks for all the input. I'm trying to figure out how to test the theory that the wing helps cool the engine bay. I don't think asking early 308 owners about their cooling will help, because of the changes made to the cooling systems through the years (fans, impellers, etc). Does anyone have access to a wind tunnel?  | ||
| Barry Wolinsky (308gtb)
Member Username: 308gtb Post Number: 630 Registered: 2-2002 |
The 308 GTB Studio Aerodinamica S/N 23611 (Millechiodi):    | ||
| Dr Tommy Cosgrove (Vwalfa4re)
Intermediate Member Username: Vwalfa4re Post Number: 1261 Registered: 5-2001 |
I always believed that thing was aesthetics only mainly because I have never read any credible source that disputed this. The only thing that made think otherwise was Ferrari's experimental car from 1977. It was called "1000 rivets" or something similar. They riveted body panals on a 308 to better the aerodynamics and to accept wider wheels, etc. (most of these exterior changes were implemented 7 years later on the 288 GTO and the dash layout went to the Mondial 8 3 years later). Anyway, it had that rear spoiler also so maybe it does do some good. | ||
| Mitch Alsup (Mitch_alsup)
Member Username: Mitch_alsup Post Number: 973 Registered: 4-2002 |
I think the upward angle of attack is to angle the airfoil to actual airflow off the top of the passenger compartment. The back of the roofline is downward sloping and the engine bay is decidely below the roofline (duh). This means that, in the absense of the airfoil, the air would come off the back of the roof and naturally fall* into the partial vacuum above the engine bay. The airfoil redirects the air more to the rear of the engine bay, and thereby, creates a small lower pressure region on the front 1/3rd to 1/2 of the engine bay. *without an airfoil, the air comming off the roof will likely tumble and become turbulent, increasing drag, and doing nothing for pulling air through the engine bay. See: "Race car aerodynamics: designing for speed" Joseph Katz. | ||
| Verell Boaen (Verell)
Intermediate Member Username: Verell Post Number: 1080 Registered: 5-2001 |
I side w/both Ric & Philip. Thought about the spoiler quite a bit after I got my car & decided the following: The spoiler's cross-section is that of an upside down airfoil. Combine that with an upward angle of attack, and you create negative lift due to reduced pressure on the bottom of the airfoil. This same reduced pressure would tend to extend backwards & below the spoiler where it would tend to suck air up thru the louvers. Now if only someone with a good fluid flow modeling package would enter the shapes & confirm/disprove this hypothesis... | ||
| dave handa (Davehanda)
Intermediate Member Username: Davehanda Post Number: 1651 Registered: 5-2001 |
Ric's explaination is the one I have heard, but I still don't think it does anything...other than as a "dress up" item. I think the cars look better w/o that add on "doo dads". | ||
| Philip Airey (Pma1010)
Member Username: Pma1010 Post Number: 372 Registered: 7-2002 |
I thought the idea of the spoiler was to increase downforce at the rear of the car (where it typically gets light) and thereby provide greater stability at speed. | ||
| Mike Charness (Mcharness)
Member Username: Mcharness Post Number: 906 Registered: 8-2002 |
Yeah, I was grateful to get the louvers and targa off my neighbor's crashed QV before it went to be auctioned off as a parts car. You should be able to buy a set from T. Rutlands from one of their salvaged 308's or 328's. | ||
| Jim E (Jimpo1)
Intermediate Member Username: Jimpo1 Post Number: 2349 Registered: 7-2001 |
I'd love to have my louvers done too, but don't want to butcher my originals. When I priced them from the owners site, it talked me out of that idea. Anybody have a wrecked 308 they'll sell the louvers from? | ||
| Ric Rainbolt (Ricrain)
Member Username: Ricrain Post Number: 544 Registered: 2-2002 |
FWIW, the official explanation is that it creates a zone of low pressure above the rear bonnet, increasing the airflow up and through the engine compartment. | ||
| dave handa (Davehanda)
Intermediate Member Username: Davehanda Post Number: 1628 Registered: 5-2001 |
Tillman, I have heard people say it is to help with evacuating engine heat, but I find that pretty dubious....I think it is purely cosmetic. | ||
| Mike Florio (Mike_in_nevada)
New member Username: Mike_in_nevada Post Number: 23 Registered: 6-2003 |
It supposedly is where the modified-field chick magnet is housed. | ||
| Tillman Strahan (Tillman)
Member Username: Tillman Post Number: 875 Registered: 11-2001 |
I'm considering changing my 328 GTS into a Charness-style GTB hybrid. I have always loved the clean lines of the early GTB. So, I was wondering if the rear spoiler actually has any effect other than aesthetics? If it is really just cosmetic, I think it'll have to go when/if I get the top and louvers done. Thank |