So I am thinking about changing 3rd and 4th gear in my 73t. Engine has been rebuilt and pushing 190 to 200 hp. Would like to know suggestions for 3rd and 4th to go thru the twisties. I plan on leaving the tall fifth to get me to my destinations. R and P standard 7:31.
Let me know of your experiences and also if i decide to go with the shorties I will need to source them.
Thanks
Mitch
1962 356 S Cab gone
1967 911S Coupe
2008 RS60 Boxster gone
1973.5 911T targa soft window Gone
Runge 008 Gone
2002 996 TT x-50 Gone
2016 Boxster GTS pts gulf orange
1969 912 SWT pts green
Can I be FRANK with you ?
Live everyday like it's your last .
Eventually you'll be right.
Per our conversation I have absolutely no clue! If you need horn grills, or wipers, I can help....
And help you do.
I appreciate you.
1962 356 S Cab gone
1967 911S Coupe
2008 RS60 Boxster gone
1973.5 911T targa soft window Gone
Runge 008 Gone
2002 996 TT x-50 Gone
2016 Boxster GTS pts gulf orange
1969 912 SWT pts green
Can I be FRANK with you ?
Live everyday like it's your last .
Eventually you'll be right.
Airport gears in my '72S from the factory, top 3: 16/35, 20/32, 25/26.
65 356SC Dolphin Gray
66 912 Green
69 911E Tangerine
72 911T GP White
72 911T Aubergine
72 911T Lilac
72 911S Black (voodoo)
86 911 GP White Targa (now sons)
90 964C4 Black Targa
94 964C2 Black Coupe
08 GT3 Speed Yellow
4sp or 5 ?
1962 356 S Cab gone
1967 911S Coupe
2008 RS60 Boxster gone
1973.5 911T targa soft window Gone
Runge 008 Gone
2002 996 TT x-50 Gone
2016 Boxster GTS pts gulf orange
1969 912 SWT pts green
Can I be FRANK with you ?
Live everyday like it's your last .
Eventually you'll be right.
I think you really need to decide the speeds you are looking for and the revs you are using.
The rev drops that result will determine the gear ratios.
I would think but haven't checked the chart that you will have around 2200 rpm 1st to 2nd
1800rpm 2nd to 3rd and 1200 3rd to 4th may not be too bad.
Be a little careful in how big a step up to 5th as too big a step will potentially shock the driveline. If you step 4th to 5th at more than 2500rpm it could be too much for the available torque.
If you look on the web you find plenty of gear calculators that will help you choice.
As an aside I thought 'Airport' gears were for a 901 when used with a '904' mainshaft and would work in the later 911 box which was fitted in early 2.4 litre cars.
Bingo.
That's exactly what I told him Chris.
If you go down 3 gear ratios on 3rd and 4th, RPM will be at 5100 after your 4th to 5th gear change, assuming you shift at 7300. Going down 2 ratios instead of 3 you can bump that up 200 RPM. No fun.
What exactly is the logic in accelerating a little quicker through "twisties" in non competitive events?
If you want to go faster through the corners my advice is to spend that $4k gear change money on a racing school. Or suspension upgrades.
Frank has the correct answer here.
It reminds me of my days with the Philly region of PCA. We had shirts made up that said - "Don't Drive Better - Just Spend More Money."
Richard Newton
5 speed. Top speed was approximately 120.Originally Posted by maverick
Car now has normal ratios, short ratios are in a box on the shelf.
Chris, I think you might be correct on the origins of 'airport' gears but I think the term was used generically thereafter for short gearsets.
65 356SC Dolphin Gray
66 912 Green
69 911E Tangerine
72 911T GP White
72 911T Aubergine
72 911T Lilac
72 911S Black (voodoo)
86 911 GP White Targa (now sons)
90 964C4 Black Targa
94 964C2 Black Coupe
08 GT3 Speed Yellow
The ratios used were very unusual and I think the Ring and Pinions are very hard to find.
Airport Circuit
Final Drive 6:32
1st 14:37
2nd 18:32
3rd 22:29
4th 26:26
5th 28:23
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