1trickpony

Most dynos I've seen, and their hard to come by, show less than than 5hp differ from 5000 rpm and up. The superchips dyno results are the easiest to check. I consider +/- 5hp flat that's less than a 3 percent variance. If you're going through the traps at 5100 or 5600, you won't see any difference on you're trap speed.

I wanted to add a link. You can see peak power with a manual trans was 170 at 5200-5400 rpm. from 4900 rpm to 5700 rpm you have 166+ hp. Pretty flat.

http://www.superchips.com/prod_imgs/makepdf-581.pdf

MSP

Just got off work.. I understand what your trying to say TrickPony.. Based on your well researched data, what is your best suggestion? Gear the car to peak out at around 4900RPM or 5000RPM?

Also, remember, I would like the 3.73 for the torque.. The 3.45 would provide more torque than the stock gear.. My goal is the 11 sec area.. We dont really know the torque value of the Turbo system yet, or how it curves with the SOHC 4.0.. Do you feel it is absolutley essential to know the dyno presence..? Meaning, is it a must to find out what the powerband is of the Turbo setup, before we choose a gear?

I just want to add, the 3.73 or 3.45 gear set would both be great starter gears... I cant think of any other gears which are so hard to choose from.. But again, this has to coincide with the Turbo setups powerband.. To not know this, makes me feel in the dark..

MSP

You will be perfectly fine with the Ford racing rear-end coupled to a girdle.. But like Jimp said, its real easy to buy a pair of slicks and get on a track and demand a nice hook action.. When this happens, sometime down the road, once we get some good tunes and leg work behind the Turbo setup, or Nitrous for that matter, things could happen.. Whether its the differential, or other drive-train components.. Right now, we all must accept, that if it can break, one of us will be the one to find out.. When this happens, you share the information, so others can avoid it.. Thats pretty much how this works.. I add 18psi of boost to the SOHC 4.0 and the heads launch through my hood.. I come here and say, dont go over 17.5psi or else.. LOL!! Somebody has got to be the first, or we cant make progress..

Conversley, I come here and say 18psi is ok on a stock motor.. I'm a hero, because I had the guts to find out.. Thats just an example, dont take it literally.. But thats how its gotta work..

Or we buy the kit from a guy like Powerhouse, and use his safe tunes.. We all meet at a track, and its a drivers race because we all have the same mods..

1trickpony

I guess I'm saying the power peak isn't that critical. CHP did an experiment with ratios, 3.00 to 4.11 gears. Trap speed never varied by more than 1 mph. So swapping 3.31 for another gear probably isn't a big deal, especially with 400+ hp. That said, a good rule of thumb is cross the traps in fourth near your power peak. As previously stated, a 3.73 (5800 rpm) is about perfect. I'm guessing traction is an issue.

rygenstormlocke

Thanks Jimp. If I go with a detroit locker, is that all I need for my rear end?

MSP

Do you have a link to the data which shows this about trap speed not varying more than 1mph from 3.00 to 4.11? I find this really hard to believe.. Of course I trust in the integrity of what your stating, however, I am more of a facts oriented type person.. So posting a link where I can visualize the data would be nice.. We do agree the 3.73 is a good gear to go with..

MSP

I got it TrickPony! You da man!! So knowing this is the case, one might as well get the 4.10's, and have the best SOTP feeling.. Although Scrming says his cruise speed at 80mph is alittle high..

4.10 @ 80MPH with 27.5in tires is 4007RPM.. So 3.73 @ 80MPH with 27.5in tires is 3645rpm... 3.45 @ 80mph with 27.5in tires is 3372rpm.. 3.31 @ 80mph with 27.5in tires is 3235rpm..





So factoring in 5th gear @ 80mph with the 4.10's leaves a final cruise speed at 80mph of 2885rpm.. So I can live with that.. Looking at the 3.73's while in 5th leaves us with a final cruise speed into Las Vegas of 2625rpm...

Thanks for setting me straight TrickPony.. Of course we all plan to finish a 1/4 mile run in 4th gear.. But I should have calculated 5th gear for the dailey driver aspect.. Now its more more understandable..

@ALL

Please take my numbers in the other post which reference a dailey driver value and disregard them.. I left the car in 4th gear, when we actually will do dailey driving in 5th gear.. TrickPony kindley debated with me until he go his point across, without questioning my calculations directly.. LOL!! Thanks TrickPony! But next time just get straight to the point.. But I will admit, the info is much more valuable now that you let me figure it out on my own... You must be a professor or something.. LOL!

With all that said, I think I will stick with the 3.73's, because the daily driver @ 80mph is good, which I dont drive that fast myself. I drive around 70mph on the freeway.. This places me at a final cruise speed home from Vegas, on my 26in tires @ 2429rpm... Likewise, while at the track my engine trap speed @ 120 mph chasing 11 sec will be 5784rpm..

This is close or in the range of the 05 SOHC 4.0's peak power range.. My car as it sits right now, I have stated pulls hard all the way to 6000rpm.. With a tune and a turbo setup, I can most likley get allittle more power out of it, maybe.. However, I feel the 3.73's gives me the best of both worlds, and I can stand behind this recommendation to other 05-V6 owners..

Now if we reference something close to a 3.55, which is what Powerhouse made a run with the single turbo test 05-v6 stang, we will see we are only offered a 3.45 as something being mildley close to the stock GT gear ratio.. Looking at these numbers, presents another option for those who do desire a somewhat torquey launch but a more reasonable final cruise speed.. Properly looking at these numbers looks more like this..

1/4mile @ 120mph= 5350rpm

Dailey Driver while at 70mph= 2247rpm

So as you can see, the 3.45 gear while only being a step above stock for the 05V6, does present you with alittle more gas savings above the 3.73 on a dailey commute to work, if you have a job.. But while running through the traps, it is apparent the 3.45 also leaves you in a pretty good situation while at only 5350rpm.. It can be debated whether or not the 3.45 gear is even worth getting over the stock gear, based on its position above the stock gear.. Only one step.. However, a significant noticable change will occure with the 3.73, because it is 2 positions above stock, in which I'm quite sure it can be noticed without any other mods being done to the car.. The choice is yours.. I feel the 3.73, is what is best for me..

Thomas S

That and gears, which you would most likely change with an 8.8 anyway. Unless you want to stick with the stock ratio, which wouldn't matter either way. An axle girdle would be good too if you want to be on the safe side. And you'd also need that panhard bar relocation bracket with the girdle. So:

Locker: $350
girdle: $150
bracket: $80
--------------
total: $580 give or take

I didn't add the price of the gear because like I said, you can add that to the cost of either rearend. You'd end up with a 7.5" rear that is stronger than a stock 8.8".

Thomas S

MSP, one thing to think about: those 3.73s will launch you harder(with good tires) and spool up that turbo quicker! So you'd get in the powerband sooner in the 1/4 and stay there. At least that's my line of thinking.

MSP

Yes Sir!! I'm off to work Jimp.. Keep the good ideas coming so I have some good reading in the morning.. LOL!! As far as I'm concerned it will be the 3.73's..

MSP

I would think about it like this.. You can save alittle money by going with the Ford Racing T-Lok, and adding the girdle...

In your mind, as your completing the rest of your mods, your thinking, please Lord, grant me enough power to the rear wheels to twist the spiders in the 7.5 Ford racing rear-end, with a girdle installed, on street tires..

I really want to know I am putting 450 to 500FT lbs of torqe to the rear wheels, that I broke the girdle reinforced spiders..

Lets be completely realistic about this.. Even if it took 425ft lbs to break the diff with a girdle installed, well I'll be gosh darn your haulin some major azz buddy!!



So to me, I am going to try and break it.. I want to break the Ford Racing 7.5 with a girdle on it.. If I can do this, I'm headed in the right direction.. And as a present to myself for all the hard work, I'll buy the Detroit Tru-Trac rear-end..

Actually, I'll take up the challenge.. My new goal is to snap 28 spline axles, and peel back the spiders of the Ford-Racing T-Lok with a girdle on street tires.. If I can get this done, I'll post the pictures of the carniage!

rygenstormlocke

MSP,

You know, you are right....I could save the money, get the Ford T-lok and put the difference towards a rear sway bar (the ford tlok is 150 less). I mean, if I had enough power to break it...I'd be very happy to replace the rear end.

Besides, my ultimate goal over the next 1.5 years for me is somewhere between 360-400 HP. If I want a 500 HP car, I will do that buying a 67-69 model mustang and restoring it. So I should be fine with this....

I think.......I'll sleep on it.

On another note, got a refferal to a exhaust guy....he is going to convert my ypipe kit to a magnaflow tru X pipe setup for under $125.

MSP

Sounds good.. My feeling on the rear-end situation has to do with a need to know basis.. Its easy to pass over certain genuine V6 Mustang parts..But is it justified.. Like I have said before, the most important thing in my book, is that we need to establish the guidelines for the 05+-V6's.. You understand its very easy for us to take GT replacement parts, and slap them on our cars. Putting an 8.8 rear-end on our cars is something I would never even consider.. I would trade my car in for a GT if it came to this.. Keeping true to our V6 herritage is the most important thing we can do.. Knowing we can get the Auburn rear-end, and the Detroit Locker are good things to know.. But what are the true limits of a ford Racing T-Lok? This is the genuine upgrade for our cars.. This needs to be established..

The exhaust work sounds like a good price..

needastang

Gentlemen I am speechless. This is an amazing thread. I am encouraged by the welcomed open debate and the ego-less exchange of ideas.

I was equally inspired by the dispositon on testing the limits, sharing results and pioneering v6 mods and performance. The "v-6 heritage statements" struck a chord with me too.

Many Thanks to all who contributed!!!

MSP

Thank you for the kind words.. In this thread thus far, I am pretty much talking with myself.. Not many seem interested in the subject, at this point in time.. But I am content to basically keep a chronilogical sequence of events for my own personal engagement.. I could care less really, if not many want to discuss the subject, or just completely ignore my thread.. I am used to being on my own in things such as this, and I will keep it that way, even after I post the video of my 11 sec run..

Now with all that said, again thanks for the kind words, and please feel free to give feedback, which it appears, most are avoiding.. But there will come a time when my total discussions will have more meaning, and those who missed it, will also be ignored by me.. LOL!! But not you!...HEHEHE!! I can tell you actually read all the info, and understand it, and the direction I am trying to take the discussion.. Most of this may not mean much to the casual eye, or to someone who thinks about a race being just a race.. I am more concerned about how the car is going to finish a race... What I mean is, the powerband on our cars, and the gearing are only important in the last section of a 1/4 mile race.. Meaning, my intention is to build a car, or modify a V6 Mustang that has its entire focus at the last 1/8 of a 1/4 mile race.. You see, this is the most important section of a race.. This section of a race, seperates the men from the boys.. If you can modify a car, that has an emphasis in this section, then you have a winner.. Most have concerned themselves with the start of the race, which is why all the concern over the 7.5 axle is apparent.. But if your intent is to win the race, you focus all you attention towards the other end of the track.. Thats what I am doing... focusing all my attention at the other end.. This is not to say that the start of a race is not important, but it is to say that how your able to finish a race, determines whether or not you win..

rygenstormlocke

Some more input for what it is worth, I was talking with the guy who does the work on my car and mentioned I am looking into a TLOK, he said mechanics all over the place make the same mistake. He said there are different types of fluid to fill it with, and the good stuff is like $17.50 a quart, but it will ensure that it can hanlde the load and make sure the tlok last a long time. He said most standard garages put in the cheap fluid and the gears blow out within 16-24 months.

Anyone hear of this?

vb101

I am planning on getting a good limited slip differential for my car, as well as bumping up the gear ratio, in preparation for either supercharging the car or replacing the heads and cam. I want to get to at least 300 hp (at the crank). I am very much interested in what others have to say on the subject, especially those who have already done the mods I'm planning on doing. Unfortunately I don't have the money to risk breaking anything so I'll be doing my research and reading what others have done so I know what I can do without big risk of breaking something. With any modification to the car there is always some risk of damage but it can be minimized with proper planning and research. I take my hat off to all those who are willing to push the limits and also wiling to share the results with the rest of us.

MSP

Yes, I have heard the same thing.. Ford makes a special oil that should be used on the initial installation of the differential...

@vb101

The most critical component with all driveline related parts will be whether or not slicks will be used.. So when researching the info, you may come across the fact that unless your going to be running slicks, the 7.5 should be good enough.. Even the 8.8 T-Lok will suffer the same damage when running slicks up to a certain Torque number.. Nothing is really promised.. But, by spending the money up front for something like the detroit locker, can put your mind at ease I guess..

I had planned on getting the Detroit Tru-Trac initially, but do have a need to know just how much the 7.5 T-Lok can take.. But of course the Detroit Locker and the Auburn are both stronger diffs for sure..

Effectively looking at it, the Tru-Trac and the Auburn could turn out to be cheaper.. If the 7.5 TLok should break, then the cost of swapping it would make it more expensive..

MSP

With the purchase of the Ford Racing 7.5 T-Lok, and the Ford Racing 3.73 Pinion and Gear set complete, I am now looking for some Weld DragLite wheels..

Since the focus of my primary objective has shifted somewhat, which is to actually break a Ford Racing 7.5 T-Lok reinforced with a Girdle, I have decided the new plan needs to be completely setup to make 1/4 mile runs..

When I restored my 1966 289 Hi-Po 4spd Mustang several years ago, I had the Weld DragLites on it.. I sure wish i would have kept the car, but such is the spice of life..

So now the search is on for some Weld DragLites!! If anyone can help, thanks.. There actually not hard to find at all, but I like to keep a type of journal of my adventures.. LOL!!

rygenstormlocke

MSP,

What size are you looking for? I can't seem to find them in 17's, which is the size I prefer. Howerver, they are in 16's all over the place. Here is a link:

http://www.streetdreams.org/display.php?s=...te&fin=Polished
http://www.streetrodstuff.com/Products/938/

And here are some 18's:

http://cgi.ebay.com/ebaymotors/WELD-WHEELS...1QQcmdZViewItem

If you want to go full retro, you can get these good year nascar wheels to give it that mustang mach1 look:

http://www.tirerack.com/tires/tires.jsp?ti...gle+%231+NASCAR

Good Luck!!!