| Author |
Message |
Hans E. Hansen (4re_gt4)
Intermediate Member
Username: 4re_gt4
Post Number: 1613
Registered: 4-2002
| | Posted on Friday, August 01, 2003 - 12:30 am: | |
Uh, Jonathon, what are you talking about? We're talking filter elements. They replace the UFI, or whatever is already there. No change to air box, filter box, or whatever. Just the element itself.
OK, just thought of this. K&N offers some bizarre "high performance, super duper, double-your-horsepower" kits that have a tube of some-such attached to a round filter. That's NOT what we are talking about. We're talking about an OEM-equivalent filter element swap. No airbox mods. |
Rob Lay (Rob328gts)
Board Administrator
Username: Rob328gts
Post Number: 5787
Registered: 12-2000
| | Posted on Thursday, July 31, 2003 - 11:30 pm: | |
My K&N fits in the stock air box. |
Jonathan (Birdman)
Junior Member
Username: Birdman
Post Number: 100
Registered: 6-2003
| | Posted on Thursday, July 31, 2003 - 9:50 pm: | |
I don't know about the GT4 airbox, but on a GTB, the removal of the stock airbox and addition of K&N filters means that the engine is now sucking hot air from the engine bay, not cool air through the vent in the side of the car. I doubt very seriously that this would improve performance. I expect it would hurt performance.
Jonathan
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Robert W. Garven Jr. (Robertgarven)
Junior Member
Username: Robertgarven
Post Number: 216
Registered: 2-2002
| | Posted on Thursday, July 31, 2003 - 11:07 am: | |
My car 75 gt4 is running rich and when I put in the K&N it really took off. I also have a tubi. I can't argue with science but my butt said it increased hp at least as much as the tubi. I have a new UFI air filre and it looks like flocked velvet I cant imagine air getting through that thing!
I am curious I scanned the article but did it say what type ignition they were using plus it looked like it had 2 distributors? I am using 1 set of stock points solid core wires, I am very happy with it like that. |
Sean F (Agracer)
Member
Username: Agracer
Post Number: 302
Registered: 2-2003
| | Posted on Wednesday, July 30, 2003 - 6:59 pm: | |
It was a Euro 308GT4 carb engine and was in tune.
It was a good article, but short on details (like all Forza articles, long on promiss, short on delivery).
Next month they are going to "go inside" and change the pistons, cams, etc and see what you can do to make a nice street car, and a full race engine. |
dave handa (Davehanda)
Intermediate Member
Username: Davehanda
Post Number: 1408
Registered: 5-2001
| | Posted on Wednesday, July 30, 2003 - 3:38 am: | |
Frank,
What year 308, was it a FI or carb car? It would definitely be understandable with a carb car. I did not do back to back testing on my 78 308 GTS carb car, but with no cats, stock exhaust and K&N air filter, the car was very lean, and was slowly upped on the main jets (dyno with exhaust analyzer) from the stock 125's to 140's. The 140's still left the car just slightly lean, but he was afraid if he went to 145's, that would end up too rich.
I am no mechanic, but I don't see how a lower restriction air filter would lean things out on a FI car; it is not leaning out the mixture, only allowing more air, which is compensated for with more fuel by the air sensor plate...right? The mixture is only changed with the mixture screw?
Anyway, one car is not true representation of what will happen with all cars. In fact, individual cars can take to some mods better than others. Not trying to defend K&N (I don't believe they really do much myself; though I have installed them on five cars and a motorcycle over the years), but to each their own...Rob definitely had a good experience with the K&N for his 328. |
Hans E. Hansen (4re_gt4)
Intermediate Member
Username: 4re_gt4
Post Number: 1589
Registered: 4-2002
| | Posted on Monday, July 28, 2003 - 7:40 pm: | |
Hmmm... Just a note: I have a K&N and a dyno test showed the mixture to be a bit lean. I don't know if it is 'normally' lean (I don't have a stock filter for comparison), or if it was the K&N that leaned it out. I since have changed jets. |
Andy Falsetta (Tuttebenne)
Junior Member
Username: Tuttebenne
Post Number: 214
Registered: 3-2003
| | Posted on Monday, July 28, 2003 - 6:03 pm: | |
I'm with Mark on this. Try taking your stock filter off and drive the car. A K&N will restrict more than if nothing is there but you can get a sense of what will happen. My car looses power because the mixture leans out. (It sounds great but doesn't run better) I don't need fouled plugs so I can live with it running leaner than some. |
Mark Eberhardt (Me_k)
Member
Username: Me_k
Post Number: 635
Registered: 5-2002
| | Posted on Monday, July 28, 2003 - 5:08 pm: | |
Changing the air filter will effect the mixture. If the engine is on the lean side, it will get worse and probably lose power. If it was a bit rich, it will gain power. You really need to have the engine in tune, then retune after making the change to know if it truely helps or hurts. That said, I have seen K&N filters not help (a stock Z3), but I have never seen one hurt...after tuning |
Rob Lay (Rob328gts)
Board Administrator
Username: Rob328gts
Post Number: 5739
Registered: 12-2000
| | Posted on Monday, July 28, 2003 - 3:43 pm: | |
I saw that. Haven't read the article, but was squinting to make sense of the charts.
That's not my personal experience (12 hp and 5 torque increase on the Dino 328)...
http://www.ferrarichat.com/discus/events/dyno2002/ |
Frank Parker (Parkerfe)
Advanced Member
Username: Parkerfe
Post Number: 2785
Registered: 9-2001
| | Posted on Monday, July 28, 2003 - 3:39 pm: | |
Did you guys read the article in the recent Forza that indicated a loss in HP and torque when a K&N was added to both a stock and modified 308 ? Makes you wonder. |