348進化の過程…

英語ですが、348の改良の歴史がまとまっているサイトがありましたので、以下にコピペ。
興味のある方はどうぞ。

これをきっかけに初めて知ったのですが、純正17インチホイールのリアは、パーツナンバーが2種類あるんですね。
違いは、オフセットの違いだそうです（+68と+43）。
以下の文章では、Serie Specialeのモデルがオフセットが+43となっているようですので、+43はSerie Speciale用ホイール？（パーツナンバーもアメリカ＆カナダ仕様と記載されています）
しかし、スパイダー、GTB、GTSも同様にリアのトレッド幅が50mm拡がっていると記載されているので、スパイダー、GTB、GTSも+43オフセットのホイールが標準仕様なんですかね〜
自分がつけている純正リアホイールがどちらなのか、気になってたまりません^^;


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Here are the improvements that were made during Ferrari 348 production:
http://webpages.charter.net/aircover/348/1994Ferrari348Spider.html


1. 05/30/91 differential side seal—production improvement
2. 05/30/91 Bosch starter motor changed to Nippon—production improvement
3. 10/10/91 cam seal housing modification—reduced oil leakage
4. 10/10/91 double plate-clutch changed in favor of single-plate clutch—production improvement
5. 10/10/91 new alignment specs—improved handling
6. 10/10/91 improved mounting of front bonnet grill to address warpage
7. 10/10/91 front suspension shocks and springs—production improvement
8. 06/01/92 rear A-arm fix point height reduction—production improvement
9. 06/01/92 Delco Alternator changed to Nippon—production improvement
10. 08/18/92 door grills—improved strength
11. 08/24/92 oil sump tank ground strap—improved gauge operation
12. 11/03/92 front timing bearing—reduced noise
13. 08/18/93 harmonic balancer replacement—reduced weight - added 2hp

14. 08/20/93 clutch thrust bearing/slave—production improvement

Other factory enhancements:

the change in final drive ratio

The 1994 348 Spiders have a 4.34 to 1 final drive ratio.

The 1993 348 TS's have a final drive ratio of 3.53 to 1 (click here: http://maximum-cars.com/Cars/Car.php?carnumber=337 ).

The 1992 & 1993 Ferrari 348 tb and ts Serie Speciale had their rear track widened by 50mm from 1578mm to 1628mm by adding 25mm of offset to each wheel, and their final drive was shortened from 26/27 on the earlier cars to 25/29 on the SS. A taller fifth gear was fitted (early cars having p/n 70000592), to maintain top speed with the new lower main gear installed (click here: http://www.ferrariclub.com/faq/348versions.html ).

The 1990 348 TB's have a final drive ratio of 3.56 to 1 (click here: http://www.supercars.net/cars/564.html).

the stainless steel fuel line change, the major change to the Spider one-can exhaust from the old 2-can muffler, rear subframe upgrade to part number 4628, the change from the Motronic 2.5 to Motronic 2.7 ECUs (at and above chassis #86406), the increase in redline to 7800 RPMs (Spider, SS, Challenge, Competizione), the battery location switch from the rear bonnet to beneath the front bonnet (1992), larger intake plenums (for GTS, GTB, Competizione), 50mm wider track via 25mm wheel offsets, exhaust cam pulley setting re-indexed (U.S. Challenge 348's and Euro GTB, GTS, and Spiders), and the front bonnet A/C fuse switch from blade to inline bullet.

1989 model Ferrari 348's did not have the mad mouse seat belts. Early 1989 models had an external radio antenna.

1992 models and up came with body colored side skirts and spoilers. SS models had a reverse curve front spoiler (and small lip), removed rear grill, kevlar seats, chrome prancing horse "cavallino" emblems front and rear, strengthened door panels, leather interior door panels, and a taller 5th gear.

Challenge models also came with aluminum pedals, an alternate fuel pump, a lighter front bumper, roll cage mounts, carbon fiber brake cooling ducts, a bigger heat shield, rubberized tow hooks front and rear, exhaust timing advanced, and 18 inch speedline racing wheels (225/40 ZR 18 front and 265/40 ZR 18 rear).

Competizione models came with carbon fiber bumpers, aluminum and carbon fiber "thin" front bonnet and rear decklid, carbon fiber undertray, F40 half-shafts, upgraded fuel mapping in the ECU chips, lexan rear window, 15 inch brakes, and a strengthened frame.


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