PeteK
GT Owner
Hah, heh. It’s the one with the broken lawn chairs and empty propane tanks strewn about...
Actually, I’m up on Green Mountain above Kalama. Looking down on the Columbia River and Portland (at a safe distance—30 miles).
3.90 ring and pinion (available again)
- Thread starter B.M.F.
- Start date
Actually, I’m up on Green Mountain above Kalama. Looking down on the Columbia River and Portland (at a safe distance—30 miles).
I can't remember when it was but we had a TT 3.90 car at a mile event and it would not go 200. It was 19X.
ultrasportracing
GT Owner
Watched a lightly modded GT run 205 at Beeville Texas Mile a few years ago. Stock gears. Stayed in 5th gear (.77). 6th (.63) is useless @ Mile. Am guessing 3.90 gear with similar setup might run 180 ish? We ran 2.70 gear in Mustang to keep RPMs around 7k with tranny in 5th (.8). Best run was 230, Same rear Hoosiers as GTs.
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sandman
GT Owner
3.90’s aren’t ideal for the mile. I shift into sixth at 185 approximately 3 seconds or around 800 feet from the one mile line, at one mile I’m usually 195mph. It takes a mile and a quarter to get over 200 usually depending on weather. I have done a 218 mph run with the 3.90 whipple gen two car pushed bye a 30mph tail wind In the mile and a half.
The 3.90’s are great fun on a road course or on the street, that’s where they shine. I do like driving the 3.90 car versus the stock geared car in both those instance but in the mile the stock geared car works better.
The 3.90’s are great fun on a road course or on the street, that’s where they shine. I do like driving the 3.90 car versus the stock geared car in both those instance but in the mile the stock geared car works better.
centerpunch
ex-GT owner x2
There are several old threads from when the 3.90 gears were first made by Stillen, LOTS of positive feedback from folks who experienced the mod.
FYI for some reason, the forum doesn't always sort posts in the correct order within old threads, but the content is still all there.
www.fordgtforum.com
www.fordgtforum.com
www.fordgtforum.com
www.fordgtforum.com
FYI for some reason, the forum doesn't always sort posts in the correct order within old threads, but the content is still all there.
Stillen 3.90 Gear Info
While I was in California I got a chance to talk to Steve Millen about their 3.90 gear. Here's what they laid out for the forum, and I'll post my thoughts below: 3.9 Gear Ratio Stillen has finalized the R&D process on a 3.9 gear ratio upgrade for the venerable Ford GT. We are interested in...
www.fordgtforum.com
3:90 Gear
I was wondering who does installs of the 3:90 gear. I live in Nebraska so I am sure I will have to travel, I am fine with that I just want it done right. Thanks Ted
www.fordgtforum.com
3.90 ratio thoughts?
Hi guys- I'd appreciate reviews of the short diff gears offered by Stillen. Since it doesn't change the RPM drop between gears, and the car is pretty torquey, how much does it change the feel of the car? Thanks.
www.fordgtforum.com
Shadowman's Experience
Well; I regularly share that which I have come to know as the result of personal experiences as well as personal opinions from time to time. In the case of the later I shared some time back my initial feelings regarding the alternate transaxle gearing as was to be offered by Stillen. At that...
www.fordgtforum.com
MarkH
GT Owner
8000rpms? That's it.... We have hung a GT out way further than that.. LOL
HOOKED ON GT
GT Owner
Any new 3:90 gear info out there.... Seems like wez back with nothing on the market again?
BMF has done some post deleting.
#hope the dream lives on.
Stu
BMF has done some post deleting.
#hope the dream lives on.
Stu
Any new 3:90 gear info out there.... Seems like wez back with nothing on the market again?
BMF has done some post deleting.
#hope the dream lives on.
Stu
They are available from John who had them made. I am just stepping aside and letting him handle sales. HCF is the company out of austin Tx.
HOOKED ON GT
GT Owner
HOOKED ON GT
GT Owner
Currently trading emails with John at https://hcfautoparts.com about the GT 3:90 set up.
He sent me some graphs and will post them if ok soon.
Was the top speed on the GT about 205mph ...if so that would be about 6,000rpm in 5th?
A 3:90 would get to 7,000rpm in 5th at abut 200mph... so pretty close (but past peak power), so how would a change into 6th act on climbing past the OE factory top speed?
6th at peak power 6,400rpm = about 225mph. (too much resistance to get there id bet)
A change from 5th to 6th has a 1,200rpm rev drop (assume changing at 6,500rpm)
You have stop watch numbers like many mention like 1/4 mile out to 1 + mile and top speed.
They all get placed on a 1 dimensional piece of paper.
Feel is personal and only the neurones firing in your brain during a peak experience hold tremendous value to you (time slips are for everyone else)
So what if a stock GT gets to 150mph in x time and a 3:90 does in 2 seconds slower (just my story) but your getting more "shit yeah" out of the 3:90 as the effort or "hustle" feels dialled up v's stock.
Your friends say "Dude it's 2 seconds slower" and your face says "like I give a shit"
Imagine if Ford did offer a 3:90 from their performance division, id bet the "reviews" would have picked that as the "choice Ford performance option" v's OE daddy long legs.
It would've taken forever to sell the GT if it came with a 3:90 as the 0=60 would be closing in on 4 secs and get not near the front page attention, but really 5+ to now 15 years later it might have been even more ledgendary?
FYI .... A 3:90 is as short as the trans will go.
He sent me some graphs and will post them if ok soon.
Was the top speed on the GT about 205mph ...if so that would be about 6,000rpm in 5th?
A 3:90 would get to 7,000rpm in 5th at abut 200mph... so pretty close (but past peak power), so how would a change into 6th act on climbing past the OE factory top speed?
6th at peak power 6,400rpm = about 225mph. (too much resistance to get there id bet)
A change from 5th to 6th has a 1,200rpm rev drop (assume changing at 6,500rpm)
You have stop watch numbers like many mention like 1/4 mile out to 1 + mile and top speed.
They all get placed on a 1 dimensional piece of paper.
Feel is personal and only the neurones firing in your brain during a peak experience hold tremendous value to you (time slips are for everyone else)
So what if a stock GT gets to 150mph in x time and a 3:90 does in 2 seconds slower (just my story) but your getting more "shit yeah" out of the 3:90 as the effort or "hustle" feels dialled up v's stock.
Your friends say "Dude it's 2 seconds slower" and your face says "like I give a shit"
Imagine if Ford did offer a 3:90 from their performance division, id bet the "reviews" would have picked that as the "choice Ford performance option" v's OE daddy long legs.
It would've taken forever to sell the GT if it came with a 3:90 as the 0=60 would be closing in on 4 secs and get not near the front page attention, but really 5+ to now 15 years later it might have been even more ledgendary?
FYI .... A 3:90 is as short as the trans will go.
extrap
GT Owner
205 mph is the top speed I've always read; can't remember sources, but possibly actually from Ford. But I seem to remember reading that the test GT taken to a Europe track went around at more than that (212?) for hours. I need to go re-read that part of Joey's book so I can spew out facts instead 
HOOKED ON GT
GT Owner
I think that run was at Nardo and was about your number (either side of 210) and ripped of tanks of gas at max speed. imagine the concertration.
Actually looking at my 150mph story the 3:90 GT could easily be quicker as its doing 6,500rpm at 150 (approx.) v's stock doing 5,500rpm (approx.)
might be slower to 60, but thats it.
I think the range from 2,500 to 4,000 would be just brilliant (street rpm zone)
Actually looking at my 150mph story the 3:90 GT could easily be quicker as its doing 6,500rpm at 150 (approx.) v's stock doing 5,500rpm (approx.)
might be slower to 60, but thats it.
I think the range from 2,500 to 4,000 would be just brilliant (street rpm zone)