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laserred
08-13-2003, 05:33 PM
:bounce: Can somebody sugget the best 410 on the market for the $. I am interestd in upgrading from 373's to 410's and I also would like to know what the best rearend girdle on the market is all for a 98 cobra coupe. I want to get a good clutch quad adjuster fo the $ too. Any help is greatly appreciated. I'm looking for good advice, and would like some suggestions on brands and cost, if anyone will help me with this. One more thing. Are the vendors in our list able to sell me any of the above parts at a reasonable cost with shipping and handling as I will be getting my local ford man to do the work, Thanks!

tcrews
08-13-2003, 10:15 PM
Get Ford Motorsports rear gears. Other than that, just about any of the clutch quadrants will be fine and clutch choice can be dependent on power levels, clutch feel/engagement and of course price.

I'm using a combo of Ford MotorSports high density pressure plate and a Centerforce Dual Friction disc. I'm using a Steeda adjustable clutch quadrant and fire-wall adjuster (stock cable).

oliascobra
08-26-2003, 11:54 PM
Why are you changing out your 3.73s?

laserred
08-27-2003, 07:38 PM
I want more acceleration and torque along with faster times out of the hole. I like speed, and bigger gears give you that to a certain extent. Besides, 4.10's are better for the 4.6 4 valve. I have had people on the forum tell me that 4.30's are better, but to me they are too big, and I want some kind of top end, and with 4.30's, you can't get that I suppose.

Ken 01-Cobra
08-28-2003, 09:21 AM
Originally posted by laserred
I have had people on the forum tell me that 4.30's are better, but to me they are too big, and I want some kind of top end, and with 4.30's, you can't get that I suppose.
Hmmm...I didn't know that! My Cobra with 4.30's still seems to have "some top end". Granted, I don't run it at 140, but it cruises at 95-100 with no issues whatsoever, and is only taching about 3600 at 95. IIRC it tops out at about 128 in 4th. The calculator says that 140 would be ~5300 RPM. How much top end do you need? ;) :D

PS...the calculator also says that 4.10's would be ~5050 RPM at the same speed. 250 RPM ain't going to squeeze ya much more top end!

laserred
08-28-2003, 11:56 AM
Yah! But how is your every day driving? I want to go to the track every now and then, and not every weekend. 4.30's would be great if I wanted to do that, but I like to hit the road and catch some back roads with out running out all of my gas in one day. The car I have is already bad enough with the lead foot I have. I think in my particular case, even though you have a good #'s point, I still want to go with the 4.10's . Plus I have had only a few guys say that 4.30's are the way, too many others have told me other wise about the 4.10's, I mean, are they not good gears?:eek:

tcrews
08-28-2003, 12:05 PM
4.10 gears are the best all around gear for the timid drivers. They are fun on the street, do okay on open-tracking and suck at drag-racing.

4.30 gears are the best "all around gear" for the 4V Cobra. Great acelleration, great on the highway and your gas mileage from 3.27 (stock) to 4.30 will be maybe 1-2 mpg less. Since you already have 3.73 your gas mileage change will be close to nothing. These cars love gears.

Way back in late '97 / early '98 the debate was 3.73 or 4.10 with most people leaning towards 4.10s (when I got mine). A few years later the debate was between 4.10 and 4.30 with most people leaning towards 4.30s. Now the big debate is between 4.30 and 4.56 (split about evenly) with some pushing 4.88s. You can NOT be afraid of gearing these cars...the engine loves it and so will you :)

laserred
08-28-2003, 12:09 PM
I appreciate that. That is the best answer I have had on this subject. I will consider the change , thanks Tcrews.

Slowbra
08-28-2003, 12:52 PM
Umm... GO do a search on SVT Performance about MPG and gears..

I'm not trying to sound sarcastic, but this topic has been the debate of the century..

I drove 70-90 MPH all the way from NC to IL and back with my 4.30s and I can assure you I was getting almost 26 MPG.. I've never seen anything less then 20 in town.. 22 I think is the lowest I have seen. Bob Cosby and his 4.88 geared 99 Cobra gets 24 MPG on the highway..

It all depends on what you want to do, if you are scared now then just go with the 4.10s... Be assured that if you drag race at the track and you are NA that 4.10s are NOT the gear you want in the car. If you don't hit the track, then whatever you get is better then what you have now.

Driveability does not suffer in the 4V cars with gears... The topic has been beaten to death and there is always something to say about it..

If you are going to be at the cookout, have spiffy give you a ride.. He is a believer..


I for one now have 4.56s in mine.. It still isn't too much.. :D

Shawn

tcrews
08-28-2003, 01:06 PM
Here are some more numbers...

Based off the corral.net calculator and stock tire size/transmission.

Since you have a '98 you have the butterfly secondaries...
For them to open you would have to be above these speeds (engine at 3250 rpm).

3.73 - 99 mph
4.10 - 90 mph
4.30 - 86 mph

So if you 'cruise' under the lowest speed your mileage won't be affected that much because you are staying under the opening of the secondaries......

Now here are your rpms for 65mph (average Highway posted speed).

3.73 @ 65mph = 2,126 rpm
4.10 @ 65mph = 2,327 rpm
4.30 @ 65mph = 2,451 rpm

So in your basic driving, look at what rpm you normally are at and add 325rpm to that number and that's where you would be with 4.30s. Add 201 rpm to your number and that's where 4.10s woudl put you. As you can see...there is a very small change either way and an extremely small change from your 3.37s to 4.10s (201rpm difference).

I wish I had done 4.30s but at my current power levels I should be pushing close to 130mph in the 1/4 mile and 4.10s top 4th gear out at 130mph. 4.30s would have me shifting to 5th :(

Anyways.....the car will pull harder and quicker with the bigger (numerically) gears. I drove a 4.56 geared Cobra and wouldn't hesitate to recommend that gear to anyone.....though 4.30s would be a good trade off if you don't hit the track that much.

Hope some of this helps.

laserred
08-28-2003, 01:12 PM
:bounce: How far can you wind 4th gear ( rpm & mph ) with 4.30's ? I need to know. I am not scared of the gears, I just want the right choice so I don't make a mistake with not getting enough or too much. I definitely would love to go faster but not fast enough to run out of umph too soon. the more info I have gotten today the more I am inticed to check them out, but by no means am I afraid of increasing my cars chance of producing speed, power and torque. Thank you for your reply, and I will let every one know what I do and what the outcome is. Thankyou everyone for the info, as it has been very helpful.

tcrews
08-28-2003, 01:24 PM
4.30 gears

4th @ 7,000 rpm = 124.3 mph
5th @ 7,000 rpm = 185.6 mph (add in rolling and wind resistence and it'll be lower, expect 160mph). You won't be able to reach 7,000 rpm in 5th.

That's the beauty of the 4.x + gears, you can pull in 5th. It'll take longer to pull to 'top speed' since you will be using 5th but it will pull.

I know for a fact that 4.10s will top out at 160mph in 5th gear @ 6,000 rpm with stock power levels.

The calculator shows 4.30s pulling to 159mph @ 6,000rpm in 5th gear.....

steve
08-31-2003, 03:45 AM
Hey ken, 3600@95mph is pretty high, I don't care what anybody says you are definetly stressing your motor more than if you had 4:10's. you're right about 4:30's having the edge in the 1/4 mile, but only by a hare. Somebody can easily make up for that slight loss by increasing their hp by 50 or less, or by just driving better than you. 4:10's are better for the street. I think they are the best street/strip compromise. Iam @ almost 3000rpm @80mph on the freeway, and that's about as high as I want to go. You're about 250-300mph more. Personally I 've been told that sustained driving @ anything above 3000rpm is hard on the motor and 3500 or above is definetly hard on the motor. I have about 312rwhp in my 99 cobra and I bet if you did beat me, it would be by a hairlength. IF I increased my hp by 50 (NA of course) I'd kill ya. If laserred wants to do a lot of highway driving, the 4:10's would be the better choice. 5TH GEAR is so low, even if you have 4:30's its still a lousy gear to accelerate in. Now if you had the closer ratio t-56 6 speed 4:30's or 4:56's would be beautiful. I know all about Bob Cosby and his 4:56 geared cobra, but he has got to be in 5th gear around town or his rpm's are going to be way up there. This means he is stuck in 5th slow low gear. Yes, 4:30's/4:56's are awesome for the track but to high rpm for around town, unless of course you don't mind driving in slow low long ratio 5th gear. Best bet, close ratio t-56 6 speed and 4:56's, without a doubt my next Cobra's tranny and gears. Later

steve
08-31-2003, 04:11 AM
HEY ken, I don't understand something, there's a guy @ www.nazman .stangnet.com that has a 99cobra NA 320hp stock internals (that's the highest na stock internals cobra i've ever heard of) with 3:73 gears and he runs the 1/4 @ 12.92. You have 4:30's and you're @ 13.25. What's wrong with this picture. YEH, he might have 15 more hp than you, but the way you brag about 4:30's being the greatest for street/strip I would think you would easily be in the high 12's. Heck, with my 312rwhp and 4:10's I know I could beat ya. Later

Ken 01-Cobra
08-31-2003, 08:25 AM
Steve...if you wish to run 4.10's, go for it. It's your car.

Naz's car is 100+ lbs lighter than mine, and he ran his time in good air. My 13.25 was run in 90 degree 85% humidity weather that corrected to a 12.87. If you're going to troll or talk smack, at least have a bit of understanding about what you're talking about.

If you wish to show up for the Drag Day in November, we can certainly find out which of us would win, under the same conditions.

smashedheadcat
08-31-2003, 02:10 PM
Yeah........... me too ;)

Like to see what 4.30's will do in mine. It's on for the drag day.

tcrews
08-31-2003, 02:13 PM
Originally posted by steve
I know all about Bob Cosby and his 4:56 geared cobra, but he has got to be in 5th gear around town or his rpm's are going to be way up there. This means he is stuck in 5th slow low gear. Yes, 4:30's/4:56's are awesome for the track but to high rpm for around town, unless of course you don't mind driving in slow low long ratio 5th gear. Best bet, close ratio t-56 6 speed and 4:56's, without a doubt my next Cobra's tranny and gears. Later

I drive around town all the time in 5th gear with 4.10s....why would I not want too? In town I'm really not accelerating quickly and I'm just going until the next stoplight anyway. If I hit a nice straight I still can't really go faster than 35mpg (in town limit) so I just stay at that speed in a low rpm (gas saving) range :) If I need to go faster.....I can drop it down to 4th or 3rd, or heck...even 2nd. I didn't buy a manual car because I don't like changing gears.... :)

Bob Cosby has also changed out his tranny to a custom T-5 (yep a T-5) with a really low 5th gear ratio so I don't like to use his car as an example.

The response about adding 50 more or so horsepower to your car to win.....why can't the guy with gears add 50 more or so horespower to his car too?? LOL

Sustained driving in the 3,000-4,000 range isn't going to be any harder on your engine....

I wish I had gotten 4.30s way back....my next Cobra will be getting those since it'll be serving daily driving status.

steve
08-31-2003, 02:15 PM
Ken, the question is, is it worth the sacrifice. You're right about the conditions, they can make a difference. My car certainly runs better in cooler weather. You ran a corrected 12.87, Naz ran a 12.92, that's a hairlength, but what the hell, you won. The sacrifice I'm referring to is the high rpm's around town and the wear and tear on the motor. You're right, 4:30's would give a little more low end push, but the high rpm's around town or on the highway may eventually wear the motor out, or maybe not, but I don't want to take the chance. Hell, the guy who put my chip in said if it was his car he'd a put 4:30's or 4:56's in. That's awesome for the track, but what about just regular driving, you're gonna have to always be in slow low long ratio 5th gear or you're rpm's will be way up there. All this talk has tempted me to sacrifice all the above and put 4:30's in, but it's just to much money. Money I can save for a na hp increase. Plus, driving @33oorpm on the freeway is to high, but of course you can drive slow on the freeway and kill trans ams and m3's @ the stoplight. If I had to do it over again I'd probably go 4:30's, but no higher, just not practical for the street, unless of course you only drive the car on the weekends, which is what I really do. Ken, those darn 4:10's cost me $750.00 to put in. The guy said independent rears are more labor and therefore more dinero. SOLID REARS were only $350.00- 400.00. MAN a 12.87 or a 12.92 is $750.00 worth it. If you know somebody who can do it cheaper, I may do it or I may just save for the na hp increase. If I ported my heads, intake and turned the cams I'd be around 350-375whp, at least that's what steve @ POWERTRAIN dynamics in HB,CA says. You know ken, steve says he can do all that and put it back together w/o Ford ever knowing. The problem is, if for some reason the motor ever blew Ford would probably take it apart and see the porting and cam work and therefore void my warranty. Steve would have to give me some kind of warranty for the work or I'd don't think I would do it. Hey ken, I wasn't talking smack and if you got that impression I apologize. I like your site, it's very informative and the video of you keeping up with a 2003 cobra is impressive. By the way, what was the ET difference between you and the 2003, it looked pretty darn close. Peace

Slowbra
08-31-2003, 05:11 PM
Bob Cosby's 5th gear ratio with 4.88's put him about where he was with the 4.30s and 5th gear before he changed it out.. (Thread Here (http://www.corral.net/forums/showthread.php?s=&threadid=297971&highlight=4.88))

Also..

Steve,

Many imports run 3,000 RPMs on the highway in stock form.. Most even last well over 100,000 miles.. (I know my 90 GST Eclipse (140,000 miles) and 98 GST Eclipse were well in the range of 3,000-3,500 RPM on most highway trips.... I for one am not worried about high RPM's and my engine failing.... It's not a windsor motor, it's a mod motor.

I'm not here to convince you it's good or bad, I'm just here to listen and help out when I can..

As far as 750 for a IRS build up and 350 for a solid.. That's a whole hell of a lot.. True Blue's labor charge for a solid axle is 230 bucks (which is like 4 hours of work).. Take the Pumpkin out of your IRS rear yourself and take it in and save 400 bucks on labor, it's not hard.. I've done it more times then I can count..

When I had the IRS with 4.30's I could run 12.80s all day long, but you are right 750 is quite a bit of investment.. Like Ken said, it's your car do what you wish :)

Good luck with your decision!

Shawn

Slowbra
08-31-2003, 05:13 PM
Originally posted by Ken 01-Cobra
Steve...if you wish to run 4.10's, go for it. It's your car.

Naz's car is 100+ lbs lighter than mine, and he ran his time in good air. My 13.25 was run in 90 degree 85% humidity weather that corrected to a 12.87. If you're going to troll or talk smack, at least have a bit of understanding about what you're talking about.

If you wish to show up for the Drag Day in November, we can certainly find out which of us would win, under the same conditions.

Ken..

When is this drag day? I'm interested! :)

Ken 01-Cobra
08-31-2003, 05:20 PM
Hey Steve...glad we got that cleared up! ;)

Yeah, the point is the original poster had already gone with 3.73's, and was contemplating going to 4.10's. In my own clumsy way, I was trying to let him know that he should go ahead and get 4.30's, because the difference's were negligible on top end and cruise and they WOULD give him better pick up and performance at the strip. I've been informed that my attempts at communicating this came off way different than I meant it to.

I am an old timer, where redlines were considerably lower than they are today. We never thought much of running a car at 3300-3600 when the redline was only 54-5600. That, percentage wise, is a heck of a lot more load on the engine than 3300 on an engine that redlines at 7000, so you can see where I might have an issue with someone saying it is bad for the engine. 3300 RPM is just that...3300 rpm. You go through it to get to 3400 or redline. Hitting the rev limiter is WAY harder on an engine than cruising at 3300 rpm, I would think. However, there is also a built in safety factor on the rev limiter, so it doesn't mean you're killing your engine when you hit it.

And truthfully, there ain't a whole lot more shifting with 4.30's than with the 3.27's. You just have to learn a different pattern for traffic. It takes about 3 days. ;)

Granted, I ain't no star mechanic, and I don't build engines, but perhaps some of those who do will chime in and let me know if I am smoking something here. :D

Oh, and the run against the 03 was about .16 difference. The air sucked for them too and he was running on street tires! I have some issues with my car I am TRYING to identify and resolve before drag day so the car WILL run where it should. ;)

JOSH...as long as you run street tires! Heheheheh....

Ken 01-Cobra
08-31-2003, 05:24 PM
Originally posted by BlackSnake2001
Ken..

When is this drag day? I'm interested! :)
November 8th (?) at Carolina Dragway. There WILL be a thread in Events, and info and registration form on the main page. Not sure if it is there yet or not. Tony????

laserred
09-01-2003, 10:15 AM
Just thought I would let all of you know. This whole thing has got my gears turning in my head. Both sides of the spectrum have good points and bad. It is hard for me to choose. I hope what ever my decision is I choose the right one. The 4.30's sound great but I still have issues with the rpm levels and each individual gear's top end. BUT, I like the idea of the times that have been shared here and with the mods I have those gears would be great. I also feel that since I don't go the track very often, I could with 4.10's and still be happy. I have got so many ideas about my car and it's potential, I don't know where to stop with mods. Anyway, I am a sucker for faster, and if it is faster, I usually want it . God luck to me and all of you. I hope to see some of you at drag day and at the dragon run. SEE YA !!!

cobrabitn
09-01-2003, 10:59 AM
Drag Day is November 8, 2003 in Jackson, SC. It sounds like we will have some more Camaros and Vettes coming to the event too! ;)

Slowbra
09-01-2003, 11:02 AM
Awesome.. I can't wait to see the details of the Drag Day...

Ken 01-Cobra
09-01-2003, 11:32 AM
Originally posted by BlackSnake2001
Awesome.. I can't wait to see the details of the Drag Day...
It is a fun time. I've been to every one of them since I got my Cobra and look forward to them! :bounce: :thumbsup:

steve
09-04-2003, 02:47 AM
Hey lasered, all these guys are right, go with the 4:30's, they are the best gears for the car. I wish I would of done it, I thought 4:10's would be enough. I should of listened to the guy who put my chip in, he said to put 4:30's or 4:56's, but I was afraid and put in 4:10's. Don't get me wrong, the 4:10's made a hell of a difference, but now I realize 4:30's would have been a little better, by about 250-300rpms. If I ever get the money, I will definetly go with 4:30's. Lasered, don't worry about your rpms, you'll be fine, just keep it in 5th on the freeway and around town. Personally, I don't care about top end that much, bottom end power is what it's all about. The initial acceleration is the greatest high, especially at the track and at red lights. The difference between 4:10's and 4:30's isn't a lot, but it's worth the money if you have it. Don't worry, your car will love the 4:30's and you'll still be below 3500rpm at 80mph, that's the fastest I go on the freeway anyway, unless of course I want to pass someone. As long as you stay 3500rpm or less for sustained driving your motor will be fine,(I had an expert musclecar mechanic tell me that). Have any of you guys heard of the NAZMAN and his 99 cobra, I e-mailed him for some advice and I couldn't believe his NA hp. He has 331rwhp and 330rwt NA. He said he was on the autoban in Germany doing 172mph. He just installed a 03 cobra aluminum flywheel, p&p intake and magnaflow's, and he's waiting for an electric water pump, this guy must be made of dough. The guy who put my chip in is working on a 350-400rwhp package for the cobra motor, and should be done in the next couple months. It involves P&P the intakes, P&P the heads and turning the cams, it's taken a while but he's almost done. He says it will be significantly cheaper than a supercharger and the hp should be enough to get me into the mid 12's. I'm saving my money for the 400 na rwhp because all those additions NAZ did will cost just as much as what steve @ powertrain dynamics will do. YOU guys should look up his web site @ www.powertraindynamics.com. The guy is a mechanical genius. I was gonna put JB shorty headers on the car but he told me the hp is negligible and the flanges have been cracking, he said they are worthless and the only headers that work on that car are longtubes. Anyway, I'd call him before you make any serious mods, because he will definetly steer you in the right direction.He is extremely difficult to get a hold of and takes forever to get back to you, but he knows precisely what he's doing and it's worth the wait. He did my chip so good on my car that I don't want anybody touching it except him. Remember, patience is a virtue. Sorry about the novel, Ilike to write. Later