Rear End

[Pimpdady753]

about how much hp and toruqe will a stock 1990 ford mustang handle, i plan on getting 4.10 gears but i was woundering how much hp the back end will handle, other wise i will have to get a new rear end. thanks.

[SkylineUSA]

4.10, thats not a good gear!

I thought you were building a torquey engine?

Why do we bother?

[Pimpdady753]

why does it matter if i get 4.10 and not 3.75 i was under the imprsion the higher the number the faster your will exellerate. and why does it matter if i have a toruque eninge and have 4.10s thanks for all the help.

[SkylineUSA]

If you have to get it right, that is why it matters, if you do not get it right, you'll just spin your tires, make first gear pointless, wasted gas milage, undue wear on your drive train, not be in your power band when shifting, and cross the line in 5th.

Go with 3.55 if you have a lot of torque, if your going to even have heeps of torque I would go even with a higher(numerically lower number) gear (3.27).

If your NA, and can rev to 7500 rpms, yes 4.10 is a great gear to have, if your have any power adder with a fairly low power band, its going to be a huge mistake!

What will be your first gear? 3.27, 2.87? You want a TKO trans right? The gears for the newer ones are....

1st: 2.87

2nd: 1.89

3rd: 1.28

4th: 1.00

5th: 0.64

Older ones have like 3.27 for first, which really suck.

If you want 4.10s, thats your call. I would never run them, unless I had a engine made for them.

[Pimpdady753]

ok ic now what about the stock rear end will it hold up to about 600hp or not. thanks

[SkylineUSA]

Sure it can handle that power, on borrowed time of course.

[Pimpdady753]

yeah it will only be for a litle wile. so its not going to rip apart when i slam on the gas, if i ever do.

[giddyup50]

Sky, I always agree with what you say but I kind of disagree with you on this one. You don't have to have an engine built to run 4.10's or even 3.73's. I don't know what you guys run over there but here (USA, Illinois) a lot of guys run 3.73's all day long. And a few run 4.10's. I never got the chance to get a set of gears in my 5.0 before I sold it, but I did my homework on it. About 30 miles south from where I am is a Ford Motorsport Dealership called Anderson Ford. They are always in the Mustang performance magazines for testing parts and for creating there own. One of the owners there who does the testing and other people I've talked to said that even a stock or mostly stock 5.0 with 4.10's will just cross the 1/4mile in 4th gear right at or just a little over redline(6250rpm). On the highway at 65mph(who does that, too slow) it's only about 200rpm's more with 4.10's vs. 3.73's. So there really isn't that much difference in the economy of 3.73 vs. 4.10's for the better performance you get with the 4.10's. Sure there are different set-ups that 3.73 or 3.55 would be better, I think alot of the road course guys go with 3.55's but more drag racers go with 3.73 or 4.10 or in some cases even higher than 4.10's (wow that would really snap your neck).

[Pimpdady753]

yeah it would, it will be intresting what my car can do when im done with it.

[SkylineUSA]

Originally Posted by giddyup50

Sky, I always agree with what you say but I kind of disagree with you on this one. You don't have to have an engine built to run 4.10's or even 3.73's. I don't know what you guys run over there but here (USA, Illinois) a lot of guys run 3.73's all day long. And a few run 4.10's. I never got the chance to get a set of gears in my 5.0 before I sold it, but I did my homework on it. About 30 miles south from where I am is a Ford Motorsport Dealership called Anderson Ford. They are always in the Mustang performance magazines for testing parts and for creating there own. One of the owners there who does the testing and other people I've talked to said that even a stock or mostly stock 5.0 with 4.10's will just cross the 1/4mile in 4th gear right at or just a little over redline(6250rpm). On the highway at 65mph(who does that, too slow) it's only about 200rpm's more with 4.10's vs. 3.73's. So there really isn't that much difference in the economy of 3.73 vs. 4.10's for the better performance you get with the 4.10's. Sure there are different set-ups that 3.73 or 3.55 would be better, I think alot of the road course guys go with 3.55's but more drag racers go with 3.73 or 4.10 or in some cases even higher than 4.10's (wow that would really snap your neck).

Yep true, but that is based on a stock or close to stock car. Boost applications, he will have a lot more power, so it will put him over the sweet spot, plus I always have milage on my mind, and 200rpms is not a lot, but it does add up.

Remember, he wants to run a 351, not a 302. Either way will work, its just a slightly different mind set.

If he goes with a 28", and 4.10 that would be cool, then it would put the car at 3.81 That would put him at 125mph or so, at 6250.

Trapping at 115 with 4.10s on the stock26", is fine, but like I said, hell have the power to trap around 125, so he'll have to spin around 6600, I see your point, but it depends on the engine. That would be little more than I would want to push a hydro.

[351wStang]

I'd feel sorry for any hydro lifter that saw over 6500 or so, and even that is alot.

Also on the deal with the gears, Skyline is right. Figure out your combo before you go any farther. Once youve decided whether or not your gonna boost it then you can start to work on gears. You still wanting to go with that big inch stroker? I would suggest a calmer set of gears. 4.10's will put you over the powerband. But like I say, figure out what you want, how long you want it to last, and $$$. Then we can help you fine tune your setup.

[Pimpdady753]

ok i will have the hole engine bye the end of jan. so ill know then what im doing.

[SkylineUSA]

What engine are you going with?

We don't mind helpin ya, we just wish you would stop jumpin around on what you need advice on, that all. Its all good

[Pimpdady753]

this block and these people bilding the all the internals. http://www.coasthigh.com/Assemblies/Ford/ford_393w.htm
kB dished pistons
H-beam super racing rods
twisted edge at 58cc 9.0:0.
TFS Stage 2
Trick Flow Box-R Manifold
TKo 600 Trans
75 mm tb and egr
42lb injectors, do i need bigger i dont know
bbk mustang 351 swap headers shortys
bbk X pipe with flow masters no cadalic converter.
msd 6++ inition and blaster coil
aluminum radiator
75mm mass air flow meter
i need a fly wheel, clutch any sugestions, fuel system do i have to get a efi fuel pump, water pump also should i get a electric water pump,
and i think that is it exept for odds and ends dis, short thow shifter, aluminum driveshaft, pullyes, sway bar starter, strut tower brace, oil pan\pump,
should i get tuulat k members

[SkylineUSA]

Did they give you a redline on that engine?

What are you going to boost with?

3.55's, sorry giddyup, but 4.10 to me still will be way wrong.