Brake Swap Q's

[stefan]

My festy need a brake job, (including drums and rotors) so i figure why put money into the stock system. What better time to do the swap!

1st question. I understand with the bigger wheels the speedometer will be off. What can be done to correct this? Where dose the gearing change? is it the spedeo gear in the tranny thats different, or is it in the cluster that the gearing is different?

2nd question. How will the added weight/ bigger tires affect gas mileage?

3rd question. Struts and coils- are they different between the two cars? which should i use?

[niklid05]

1) guess :lol:
2)couldnt tell you. Shouldnt affect it too much. Its not that much weight added.
3)aspire. I believe its gonna sit a little higher though.

[Sho_tyme_psi]

#3 I used all the festy shocks,struts on mine.

[skeeters_keeper]

1) depends on what tires your using... the mph (kph) won't be off *that* much, just use an online tire calculator to get an idea for how much it will be off

2) a larger diameter (taller) tire will give you better mileage @ hwy speeds, the added weight will decrease your milege ever so slightly (not noticable really) in town.

3) use the festiva stuff unless you want the car to sit higher. the connection points on the top/bottom of the struts (both front and rear) are the same from festiva to aspire so it is possible to use either set up, or a combination of both. the front aspire/festiva struts are the same as far as size, but the aspires are a little stiffer. the aspire springs in the front are longer and stiffer. in the rear the aspire strut is longer, and the springs are stiffer/longer. you will raise the car about 1" (iirc) if you use the aspire stuff... if you use the stiva stuff you'll obviously remain @ stock height


good luck, going w/ the swap is deff the way to go if your breaks really need all that done to them!

[Safety Guy]

Go for the swap, Stefan!

If you are cheap like me, get good used Aspire struts and cut the springs at least one coil to get about the stock Festiva ride height.

Use '91 to '95 Escort tie rod ends to save money over new Aspire tie rod ends. You'll save at least $10 per side, maybe more.

I always go with the manual Aspire front brake calipers and rotors. The MTX rotors alone are three pounds lighter per pair than the thicker ATX Aspire rotors and provide much better braking than the Festiva brakes.

The 175/60-13 tires will give you about the same speedo readings as the stock Festiva tires. I'm using 165/70-13s, which makes the speedo 4.5% slower.

The speedo calibration gearing is in the transaxle. When I go to the Aspire ATX, my tires will then be spot on, since I'm running stock Aspire tire sizing.

Karl

[stefan]

ah yes, according to the calculator the 175/60-13s will only put the spedo off by .8% are these the best tires to use? why did you go with the 165/70-13s?

for the spedeo gearing, is the difference maybe in the spedeo gear that you pull out to pour in trans fluid?

Is there any reason why i couldn't swap just the rear for now? My front tires are new, and i can live with my front brakes for now. But my rear suspension needs work, the drums hake a horrific metal-on metal scraping sound, and my rear tires are bald. and $$ is kinda an issue.

Ill have to see what i can find in the yard. Usually they dont have any aspires, but last time i was there there was a clean looking aspire waiting to be processed. I have a feeling im not gonna have fun removing the parts tho, with all the rust up here. :roll:

[skeeters_keeper]

you can drive with just the rear, your car will just have 13's on the back and 12's on the front. i drove my car like this for a few days during my swap while i was waiting for my new calipers to arive... no problems at all!

also, with just the rear swaped you obviously won't have any difference in spedo reading

i'm going to be needing new tires soon, right now i have 165/70s on the front and 175/70's on the rear (because the 175's aren't balanced and its a lot less noticeable in the back :lol: ), i think when i get new rubber i will go w/ all four 175/70's becuase their common, cheap, wider, and have more sidewall to absorb road bumps... you just need to decide if your going for performance, comfortability, cheapness, etc... i think 175/70's are a combination of them and should be good enough for me untill i get 14's for the summer or something... just my $.02

[Safety Guy]

Stefan wrote:

Ah yes, according to the calculator the 175/60-13s will only put the spedo off by .8% are these the best tires to use? why did you go with the 165/70-13s?

I'm a little leary (or leery, I looked it up and it can be spelt (or spelled) two different ways) of putting a 175/60 tire on a 4.5" wide rim, others have apparently gotten away with this for years with no problems. So putting those on Aspire steelies or alloys should be fine. One reason I went with 165/70s on my Aspire alloys was to put the maximum rubber on those skinny wheels as I could stand, since I'd want a minimum of a 5" wide wheel for the 175/60 size. The main reason, however, was that running a stock size Aspire tire would give me a more accurate speedo reading when I swap to an Aspire ATX. The Aspire tranny also will give me a lower final drive ratio for quicker takeoffs.

Essentially, I will have all Aspire running gear!

As for the Falken 175/60-13s, I believe most folks would agree it's one of the best tires you can use. I've heard good things about the same size Sumitomos as well, though I'm not sure they are all-season tires like the Falkens.

Also:

For the speedo gearing, is the difference maybe in the speedo gear that you pull out to pour in trans fluid?

I don't think it's that easy! I believe the speedo ratio is determined by some gear inside the transaxle, probably the gear that the speedo cable bottom fits into. I could be wrong. Maybe someone will correct me on this?

Nate wrote:

I think when i get new rubber i will go w/ all four 175/70's becuase their common, cheap, wider, and have more sidewall to absorb road bumps... you just need to decide if your going for performance, comfortability, cheapness, etc... i think 175/70's are a combination of them and should be good enough for me untill i get 14's for the summer or something... just my $.02.

I'd agree. If your car is not lowered too much, the 175/70-13s should work fine without rubbing.

The 175/70-13 size is what many Aspire owners switch to when they find that the original 165/70-13 tires are harder to get. Or they go to the skinnier 155/80-13s. Both are almost the same diameter.

The first set of Aspire alloys I got from the 'yard had 155/80s on them (which incidentily, are still for sale for cheapcheapcheap!). The second set were the following mix:

165/70, 155/80, and two 175/70s!

On the two Aspire steelies I've bought, one had a 165/80(!) and the other had a 165/70.

Now keep in mind that when Festiva owners get a new set of tires, they often got, and mostly now get, the 155/80-12 size, since it is a lot more common and usually quite a bit cheaper than either the original 145/80- or 165/70-12s. So most Festivas have been riding on larger diameter tires for quite some time!

Karl

[muscle_Car1]

For the speedo gearing, is the difference maybe in the speedo gear that you pull out to pour in trans fluid?

I don't think it's that easy! I believe the speedo ratio is determined by some gear inside the transaxle, probably the gear that the speedo cable bottom fits into. I could be wrong. Maybe someone will correct me on this?

Yes it will change the reading. Larger diameter tire, more circumference, more distance traveled per rotation = Incorrect reading of the speed. The gear inside the trans is asssuming the tire diameter is the same as stock, to make the speedo run correctly.

http://www.paspeedo.com/calculator.htm

The difference between the 175/60r13 & 175/70r13 is almost 4mph @ 60mph.
Compared to the stock festiva size the the 175/70r13 is off by 5mph @ 60mph.

[Dave G]

The difference between the 175/60r13 & 175/70r13 is almost 4mph @ 60mph.
Compared to the stock festiva size the the 175/70r13 is off by 5mph @ 60mph.

Well, that's assuming that the speedometer is dead-nut accurate on it's own, which it probably isn't :roll:

[stefan]

OK, thanks for the help guys.

One more question, aprox what dose the rear axle (or whatever its called) weigh?

[Safety Guy]

I've never weighed rear axles alone, or the assemblies. Next swap I do (hope to do another one before summer is out) I will take weights of the two different axles and the individual drums for comparison purposes.

The main weight differences should be the rear stabilizer bar and the larger drums. Anything else is probably negligible.

Now I'm thinking if there's a good way to install a hollow steel or aluminum stabilizer bar to a Festy rear axle, and how hard it would be to install the Aspire drums on that axle. Shouldn't be too difficult to save five or ten pounds.

Karl

[stefan]

i was just looking for a rough estimate... AKA- if i pull one tomorrow at the yard will i be able to carry it out by myself :lol:

also, i know the difference between the auto and manual fronts, but is there any difference between the manual/auto rear axles?

[Safety Guy]

No difference between ATX and MTX rear axles or brakes.

If you have no wheelbarrow, you might take off the drums to make your load lighter for the trip to your car. Otherwise, yes, you can pick them up with average strength. I'd guess maybe 75 to 90 pounds for the loaded axle assembly? Just a WAG.

But I am serious about reducing weight. Especially on a live rear axle beam.

Karl

[boostmaster]

sorry to intrude on this thread but you guys seemed pretty knowledegable...
I'm a festiva newbie...
I just picked up an 88LX w/ 13" rims Can I use a 180/60R13 (or is it a
180/70R13.)? I found them at Walmart for $40

Not concerned about speedo just want the widest tire I can stick on a 13" rim...