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Discussion Starter · #1 ·
Anyone have exper with using Alum flywheels on 5.0? I just put a Alum FW, New clutch and Alum D/S. It feels like I've lost 1/2 my power.... I understand the rotating mass concept, but It seems to me the car should at least accelerate hard, then drop off between shifts, but this thing is dead across all gears and RPM ranges.

One note-- I did also replace the stock exhaust with a set of BBK equal headers and a BBK off Xpipe- The X pipe doesn't reach the flowmaster muffler pipe on one side I have to get a shop to modify.. So maybe the lack of backpressure???? One side of the X is bolted up the other isn't.. The power loss is so drastic, doesn't make sense to me


Please send help.. This is the project from hell (Theres more weired stuff for later) :sosad:
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if your engine is stock it cant rev as fast, but i would say the off road x pipe with no cats is killing your low end power, the cats will definitely help your performance on a stock or slightly modded engine
 

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You need to get that exhaust problem fixed. That can majorly screw up everything.
 

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Discussion Starter · #4 ·
Thanks for your suggestions. I ended up leaving the Xpipe on. I was able to get the pipes in place correctly with a sleeve. I may go back to the cats, I have lost lots of low end power, but have more power in the higher RPM ranges.

One other thing I overlooked is that when I rebuilt the trans I changed the cluster gear ratio and first from 3.55 to 2.95. I've only had the car for a few months I haven't checked what ratio the rear is, but I know its not stock. Maybe lower gears in the rear will compensate for the gear change in the trans. The reason I changed the cluster and first gear was because first was to low and overall highspeed crusing was horrible, turning to many RPM at 70-80MPH.

Not sure what I'm going to do next-- Have stock TB and Intake, maybe I need more airflow?

thanks again
 

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ok...
What do you mean by the "cluster gear"? Are you talking about all five gear ratios in your t-5 transmission? If you are, putting in "lower" gears (such as 3.55 or 4.10's from the stock 2.73's, will just undo the same problem you attempted to fix by changing gears in the transmission. If you have feel that your rpms are too high at a given speed, first make sure your speedo is correct, then decide what gear it is in... If its only 5th you are worried about for cruising, then you only want to change 5th, if its 1st, then just first or maybe both, but if you lower all of your gears, then you have effectively removed torque from the ground. If you put higher gears ie. your 2.95 first, and then 3.73's in the rear, you are just wasting money, because you are simply putting the same multiplication of torque in different places...

A stock Mustang puts down 2702 lb/ft of torque to the rear wheels (accounting for gear multiplication) 300 lb/ft * 3.30 Nt(tranny gear) * 2.73 Nr(differential gears) = 2702.7 lb/ft @ max torque.

Anyway, my point is this, what you want to do is find a lower 5th gear ratio, and a first gear ratio, then lower your end... This way, you dont sit and spin in 1st, and in 5th you can still drive at low enough rpms to get good gas mileage. I have had the same thoughts, but have had very little luck finding different gear ratios for a t-5, especially a 5th gear lower than .68. I would really like to change the ratio to .50:1, that way, I can keep my current 2.73 gas mileage and still have 3.73 gears, although I am not so sure that it would be worth all the trouble...

Good Luck
 

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i installed the g-force synchr t5 in my car, the first four gears are about the same as stock ratios however 5th gear is a .59 great for the highway. with 373's and 275/50/15 at 75mph i am under 2500rpm, cant get much better than that
 

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3.35 is the stock first gear on T5's , not 2.95. I dont know where you got a 3.55 gear but that would be much worse than 2.95 because 2.95 is a much longer first gear. I put in a 2.95 first gear for that reason.

2.95's were stock on Cobra and T5Z transmissions.

Changing your first gear will have no affect on any other gear. If you want to change the rpm in that gear you need to either change that gear in the transmission and/or change the rear end ratio.
 

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where did you get those gears Nails, and how much???

Also, Ghost how was the 2.95 1st?
 

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http://www.g-forcetransmissions.com/tran_gt-5.asp

check out their website it will give you all the info you need. you can send them your tranny and they will install the gears, or you can order a complete tranny from them, or you can get the gear set and install it yourself. the synchro t5 what i have from them is good for 600hp. the tranny is great, blows tremec away, ive had bad experiences with tremec, gave these guys a shot and i am not dissapointed. your gonna pay a bit more than a tremec but its worth it.
 

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Discussion Starter · #10 ·
I do have the 295 first, which is a big improvement...

I bought my rebuild parts from Hanlon Motorsports they were very helpful they even sell a step by step how to video. D+D has lots of stang trans parts as well

Well I've been on the road for a few weeks now. I'm liking the changes, just have to drive a little different, the loss down low has been replaced with a decent mid and much stronger topend. Pulls hard from 80-100. I think once I add more power it will be even better. Heads, Intake, cam coming up next...

Anybody have an opinion on the new BBK SI intake? :worship
 
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