MSP

Getting Trac-Lok installed soon... Gonna go with the 3.73 gears and pinion set..

To strengthen the differential spiders alittle more, I am going to attempt to also get this Girdle installed..

http://www.drivetrainspecialists.com/categ...oduct-1077.html

I checked it out, and it looks like it will fit.. What do you guys think?


Let me explain why the 3.73's I feel are best for what I intend my setup to do...


While the 4.10's may produce a thrusty feel going from light to light, the 3.73's will have this also, but help me at the other end of the track..

Example..

I want to be able to make 1/4 mile passes at 120mph.. Thats my goal for this car.. This should give me an ET of 11sec.... Of course this is plus or minus from anywhere between 1-9 10ths of a sec..

Now, we all know our SOHC 4.0 motors are setup to produce HP peak at around 5500RPM.. So using 5500 as a guide, I make my selection of the gear..

We will concentrate on these 4 gear selections...

1. 4.10

2. 3.73

4. 3.45

5. 3.27

I will show you the numbers based on my cars tire size which is 26in.. This consist of 17" wheels, on 255-50-17 ZR tires..

For the 4.10's which is a popular choice the numbers are as follows..

1. 1/4 mile run= 120mph @ 6263rpm...
2. Dailey driving= 70mph @3653rpm

So with the 4.10's we can see that for one, my goal of a 120mph 1/4 mile run is put in jeapordy because the 4.10's takes the motor to far out of the range of usefull power... Lets look at the others.. We will skip the 3.73 for the last option since it is the gear of my ultimate choice..

3.45 Pinion and Ring gear Set

3. 1/4 mile run= 120mph @ 5270rpm
4. Dailey driving= 70mph @ 3074rpm

This particular setup is really good.. This setup allows me to make a 120mph pass, without too much high rpm work, but yet is sitting squarely towards the range where the engine is just starting to build up to it peak power range.. Actually, a tough choice not getting this gear set..

3.27 Pinion Gear set

5. 1/4mile run= 120mph @ 4995rpm
6. Dailey driver= 70mph @ 2914rpm

The 3.27 gear set, is for the logically minded performance Mustang enthusiast.. This individual has his priorities straight... In the 1/4 mile, again we can see that it places the engine where it needs to be... Hopefully you wont get run down by the competition in the last 1/8 of a mile because you will not cross the line at your peak HP number.. But you will save more gas on a dailey basis, and still put up a good show at the track...

3.73 Pinon Gear set

7. 1/4 mile run= 120mph @ 5698rpm--running through the traps!
8. Dailey driver= 70mph @ 3324rpm

So as you can see, with my selection of the 3.73 gear, I have chosen to have a slightly better 1/4 mile engine rpm trap speed, in the sacrifice for alittle bit higher rpm dailey driver... What you can see is, with this gear, I have palced the engine in a situation where as I cross the traps, I am using every bit of power my 4.0 SOHC motor can give me, based on my SC boost, or nitrous injection.. Its not maxed out, and its not a a point where it has not reached its peak.. Its in a state where I am in full use of the capapbility of the engine and cannot be run down... This means, if I get hole shot coming out of the hole, I have a pretty good chance of being able to hold off my advisary.. With the other gears, such as the 3.45, or 3.27, you can easily see, that for me to make the engine spin up quickely enough to place me in the proper power band as I cross the traps, I need to either increase the boost level, or the nitrous shot level..

So take that to mean, if you paln on running lets say a 75 shot with 3.27 gears, and the other car has 3.45 gears on a 75shot, you would need to increase the jets to the 100shot level to keep up to him or beat him..

Lets say one guy is running a 75 shot with 4.10 gears, and the other is running 3.27 gears.. The guy with the 3.27 gears will need a 125 shot of nitrous to be competive with this individual.. So now its plain to see that the lower gear you select, the bigger shot you will need if racing someone with a similar setup.. Now this does not take into account for bad launches.. Of course bad launches will happen, and when it does, its going to depend on how quickely you can spin up with good traction to make a stand against your foe.. There are also other circustances which could also effect this, but for the most part, you should understand the concept.. There may be other opinions on this subject, and I welcome any and all input.. Thanks!! I like the 3.73 gear choice for myself, most of all!

MSP

Also, I just want to be alittle more precise in this interpretation..

In regards to the 3.27 125shot vs. the 4.10 75shot, this is not absolute, just an example.. My feeling is, the 3.27 setup would most likley run down the 4.10 car before they both cross the traps.. Testing with this setup has not been done, and it could very well be that the 125shot level could spin the motor up into the proper range fast enough to overtake the 4.10 car at the 75shot level.. The example was not intended to mean that it is obvious that the 3.27 car would lose with such a huge shot, but to show the engine rpm speed is not palced at its full potential..

A better comparison would be to maintain both cars using the 75shot level.. This way, you can see what the engine rpm trap speed would be, and how allthough the 4.10 car would be out of its range, it is able to make peak power before the 3.27 car..It is possible all that is needed for the 3.27 car is a 100shot of nitrous to make up the difference, and overshoot the 4.10 car.. But the numbers, which are accurate do show that the 4.10 gears do allow you to make peak faster up to a certain point.. But overall, places the car too far out of range.. So take the comparison with different nitrious injections with a grain of salt, and focus on engine rpm speed as a determining factor as to whether or not your using all your power, or left some on the table when you crossed the traps.. Leaving some on the table means, that you could get run down in the last 1/8 of a mile, or if you dont get off the line first, your chances of catching up deminishes!

Thomas S

You could always get this:
http://www.lmperformance.com/5994/73.html

MSP

Sweet Jimp!! Thanks for the link.. I'll pick that up, so everything goes smooth...

Just so you know Jimp, I'm getting close to being able to help you out with the 05 V6 setup... I am starting to buy parts, and should be ready for us to start getting these 4.0's into shape soon enough.. Allthough I am heading for some type of ultimate SC or Turbo route, my initial setup will consist if nitrous to get everything worked out in regards to drivetrain and engine setups...

Things on the agenda will consist of new dished pistons and heads by sometime this summer... I am still waiting for Powerhouse to release his Single turbo application for our cars before I make a decision either way.. It is important to me to buy one of Powerhouses first Turbo applications for the 05 V6, because I told him I would.. So hopefully he can get it done in the next few months.. In the meantime, I will start getting other items up to snuff and test it with the nitrous in the short term.. I will definatley be picking up the item you listed, because I know I will need that girdle in place by the time I make my first 1/4 mile run..


Have you had a chance to get back to the track and run the sauce with the stock rear-end?

Thomas S

Nope, haven't gone back to the track yet. With my wife's work schedule, it's hard for me to get up there.

Looks like you've been busy! Can't wait to see all the stuff you put on.

MSP

Had the pleasure of corresponding with Powerhouse today.. He informed me that the new Single Turbo system has been installed and is in the process of testing and refinement..

Thus far, the car is running a 12.55et @ 8.7psi with 3.55's.. He made some runs at Bowling Green last weekend.. He also said that the kit would be ready to go by the 1st of the year..

Which fits perfectly with my time table.. This gives me time to get all the little things done first..

So looks like I'm in it for the long haul in regards to the turbo.. He expects to bring the car closer to 11's soon, which also fits right in with the amount of perfrormance I am shooting for...

http://www.powerhouse411.com/products/must...05_L1_turbo.php

MSP

Also Jimp, it looks like I might go with the 3.45's afterall.. Powerhouse is now settled on the 3.55's because he went on and swapped over to the GT 8.8 rear-end.. All his calibrations will be based on the 3.55 gear set.. Which means, It is probably better for me to get as close as possible..

So it seems more than likely that since he feels we will need longer legs for the turbo setup, the 3.45 gear set fits the bill.. I am impressed with its 1/4 mile trap rpm speed, and the position of it when it runs through the traps..

http://www.drivetrainspecialists.com/categ...oduct-1072.html

If we look at Powerhouses time with the Single turbo setup, and his trap speed which was 111MPH we see this scenario with 3.55's..

1/4 Mile= 4830RPM give or take a couple of 100rpm either way..

Dailey driver= 3046rpm @ 70mph..

Conversley, the 3.45's will look like this..

1/4 mile= 4694RPM

Dailey Driver= 2960RPM @ 70mph..

This is based on 27 in tires, which should be close to what he is running..

So with what appears to be a early developing single turbo system, which does seem to not show much signs of lagg from the line, the 3.45's should be able to get spun up rather quickley with almost 9psi of boost..

I will debate the scenario somewhat and decide soon.. I dont really want my car to have the ability to run much faster than 120mph period.. With my Drivers license so specialized, I cant afford to get caught doing 135mph down the freeway.. Which knowing me, if a vette tried to punish me I would.. Lets look at those numbers with the 3.45 gear set..

3.45 Gear Set 135MPH= 5929RPM

So you can see, it is doable with the 3.45 gear set, which makes it really dangerous for the normal commute car/ Drag racing freak.. LOL!! I think I'll stick with the 3.73's.. They look like this..

3.73 Gear Set 135MPH= 6410RPM

As you can see, the 3.73 keeps you safe and sanity intact.. Anything lower with 8.7psi of boost pushing you, and you may end up in a freeway showdown with some ricers, vettes, vipers.. LOL!!

MSP

Well based on this new video from a race with Powerhouse, it looks like my final choice will be the 3.45 Pinion Gear set! The stock Gt is running 3.55 gears, and you can see what a difference slightly longer legs make with a Turbo system which spools up in the last 1/8th of a 1/4 mile run.. The amount of track made up in the end is only special thanks to HP and gearing!

Here is the Video provided by 169Stang and touched up by Sixtey-Six!! Thanks guys!

http://169stang.2005stang.com/powerhouse0510.67.mpg

1trickpony

Great post, very informative. Just a couples points: I would use 3.31 for the ratio comparison. It is the stock ratio and I don't think most owners would swap it for a 3.27. With a blower, the power peak will move up the powerband even with a roots or twin screw. Your power peak will be closer to 6000 rpm. That said, power is basically flat from 5000 to 5850 rpm on a stock motor so anything in this range will have the same basic trap speed (within 1 mph). Most comparisons of ratios show maybe .2 or .3 of a second advantage with a 4.10 versus a 3.27 at this weight and power level. A shift into 5th with 4.10s would probably negate most of that. 3.45 or 3.55 sounds good. I noticed a lot of the 10 second Cobras run 3.55 or 3.73 gears with a higher redline. This sounds like a awesome project. I'm guessing around 400 HP at the wheels for a 120 mph trap speed.

Thomas S

I dunno MSP, the stock gears are 3.34s. It hardly seems worth it to change to 3.45s. You won't even notice the difference on the street. Is this going to be a track only car? Best of luck whatever you decide. I'm looking forward to your results.

MSP

Your absolutley correct.. Working the numbers on the stock 3.31 ratio looks darn good.. LOL!! This might just save some money! Looking at the numbers...

1/4 = 5133rpm

Actually revising the numbers, the 3.73's do look pretty good at 5784rpm @ 120mph..

MSP

The stock gears are 3.31's Jimp.. I may go for the 3.73's.. But he is right, the stock gears would work.. The 3.73's would give off alittle more torque...

Keep in mind the goal is somewhere close to 11sec.. I'll be completely happy clicking off an 11.99.. LOL!

MSP

Actually trickponey, in our Motors, the power is not flat from 5000 to 6000, it peaks anywhere between 5250 and 5500, give or take alittle based on the weather conditions.. But I like your thought process for sure.. Keep it coming and thanks for sharing your input!

Thomas S

Oh right, 3.31s, my bad. I don't know. You seem to have the numbers all worked out for 3.45s. That might be the best for what you want at the track. All I'm thinking about is how much fun the 3.73s would be at the stoplights.

Thomas S

He's got a point: with a turbo you'll have a lot more power at higher rpms. That might be worth factoring into your math.

MSP

Which looks like it does put the 3.73's close to the top of the list.. Now with the 3.45's, I was thinking this is a good gear once the boost level can be safely upped, by way of a lower engine compression, by way of dished pistons..

Kinda putting the carriage before the horse.. LOL.. But you know what I mean..

Like I said, us V6 guys must plan each move carefully.. Nothing wrong with looking at all angles.. Even the angles on the other side of 11 sec..

Fazm

wow, what is that ET say on the board? i cant read it clearly enough. 12 something lol. Id lean towards that before i leaned towards the nitrous, even for 5x the price.

MSP

Thats where this thread is headed.. Nothing wrong with the Nitro to test parts and engine tolerances.. But I want to set the car up based on 11sec and 120mph trap speed.. This way, when 11 sec sees me comin, it will duck!!

rygenstormlocke

All,

I am just a novice and paying close attention here. Great thread by the way! I do have a question though, there is talk of strengthing our rear ends when doing power adders and my question is this. If we put a detroit locker, tloc or other rear end components, what is the cost differential vs. going to a 8.8 rear end? If we add up all the rear end mods, wouldn't it be cheaper to just go the 8.8 route and simpler? Didn't pwrhouse have to change his out? Can our rear ends handle 400 RWHP with little modification?

I'm just curious because I'm paying close attention as someday I will put a turbo or pro-charger on my ride or something like that and want to build up to that. My x pipe goes in this week, my intake and custom tune go in over the weekend and my next logical step will be the rear end since I do not have power to both wheels.

Thanks all!

Thomas S

You can get a Detroit Locker TrueTrac for $350 or so. Or you could get an 8.8 for $1000+. I'm getting the TrueTrac.