2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

best way to get more low end power

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Old Jun 17, 2005 | 01:31 AM
  #26  
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Wait wait wait, and will this work on an auto? This does sound rather ineresting.
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Old Jun 17, 2005 | 01:49 AM
  #27  
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it does sound nice i wouldn't mind having it done to my rear end since i don't break 100mph to often
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Old Jun 17, 2005 | 01:56 AM
  #28  
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Originally Posted by Pat McGroin
Yeah, your car definitely needs some reliable American Muscle baby, straight from the powerblock on Spike TV.

POWERBLOCK BABY!
lol, a friend once told me, a v8 swap is like shooting steroids, you get real big but your ***** are still little

Racing beat will make you whatever gears you want, of course it will probably run atleast $700 for a custom set.
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Old Jun 17, 2005 | 03:33 AM
  #29  
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oh yea not to mention w/ a t-56 trans 6-speed in 6th gear on highway u can get around 28-30 MPG... w/ a 4.11 rear
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Old Jun 17, 2005 | 03:48 AM
  #30  
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Originally Posted by BichizleMyNizle
oh yea not to mention w/ a t-56 trans 6-speed in 6th gear on highway u can get around 28-30 MPG... w/ a 4.11 rear
Shoulda bought a camaro then, eh?
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Old Jun 17, 2005 | 07:04 AM
  #31  
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never heard of 4.7 gears. Tri-point has 4.30, 4.44, 4.88, 5.12 rear end gear sets for sale last I checked before I did a t2 swap. This would be a great mod for a NA or a mostly stock t2. But once you go with a big single traction is your biggest problem so no need for lower gears. Also as I said before if you go with a smaller diameter exhaust it will raise your torgue numbers and lower your hp a little. 2.5 will get you better TQ numbers. 3 inch exhaust will net you higher HP numbers so build your setup to what you plan on doing with the car
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Old Jun 17, 2005 | 07:31 AM
  #32  
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racingbeat states that they will make you any gear set you want.......
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Old Jun 17, 2005 | 08:21 AM
  #33  
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Originally Posted by sub9lulu
i'll get like 8 mpg on the highway if i got the 4.7 rear gear
FWIW, my S5 N/A has a 5.12 rear gear, and the shorter .757 5th gear and a 225/45r15 tire. In a pure race environment, it averages 8.75 mpg. That is Every shift at 8400+ rpm. I don't know what it will do to the mileage on a TII though. Additionally, that is enough gear to run Daytona without running out of gear(approx 140 mph). Your street tires are probably a little taller, but you'll still have to deal with 4,000 rpm cruising on the highway.

I'm not familiar with a 4.7 gear, but i think I've seen a 4.6 modified to work in a 2nd gen diff. IIRC, it came out of a Mazda truck.
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Old Jun 17, 2005 | 09:16 AM
  #34  
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what would be sick would be really short diff, like 5.12, and an extremely tall 5th gear for cruising. how major is it to change the ratio of one gear in your stock gearbox?
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Old Jun 17, 2005 | 09:40 AM
  #35  
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Originally Posted by tie pilot
what would be sick would be really short diff, like 5.12, and an extremely tall 5th gear for cruising. how major is it to change the ratio of one gear in your stock gearbox?
haha yeah you can be at 8000 rpm's in fourth going 60 and shift to 2000 rpm's in fifth going 65! good theory but i think its a little radical and sort of janky.
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Old Jun 17, 2005 | 09:44 AM
  #36  
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Originally Posted by NOPR
haha yeah you can be at 8000 rpm's in fourth going 60 and shift to 2000 rpm's in fifth going 65! good theory but i think its a little radical and sort of janky.
yeah!
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Old Jun 18, 2005 | 06:50 PM
  #37  
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Originally Posted by AREITU
Shoulda bought a camaro then, eh?
i did and i put the drivetrain in my 7... camaro weighs 2 much silly and doesnt handle as well
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Old Jun 18, 2005 | 07:00 PM
  #38  
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CAN I add to this silliness, I do have this V-12 Jaguar engine would it help if I put it in a RX-7, course then I need a 3.55 final drive ratio, with automatic! RON
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Old Jun 18, 2005 | 08:48 PM
  #39  
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V8 swap is your best bet, and if you do it yourself it will cost you $4000 CDN roughly to get an engine with roughly 500 hp off the crankshaft.
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Old Jun 18, 2005 | 08:56 PM
  #40  
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yeah i didnt even realize this thread was still alive. im keeping it to a true rotary car though. i dont want a motor swap unless its to maybe a 20B...
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Old Jun 18, 2005 | 09:19 PM
  #41  
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Originally Posted by MattB
yeah i didnt even realize this thread was still alive. im keeping it to a true rotary car though. i dont want a motor swap unless its to maybe a 20B...
You obviously don't have a clue how much time and money this is. Go with a V8 and save yourself the headache if you want tire-spinning torque at low RPM, otherwise, use a T60-1 with 0.96 trim and properly port and tune it...you will hit 400+ hp easily and for little cost in comparison to doing any engine swap. Besides, what are you going to do with 400-500+ hp anyhow? Probably spin out of control on the highway and kill yourself and others...Don't worry about big HP #'s unless you just like to talk big... Learn how to drive safely before putting yourself in a position that is unsafe.
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Old Jun 19, 2005 | 10:17 AM
  #42  
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Originally Posted by ronbros3
CAN I add to this silliness, I do have this V-12 Jaguar engine would it help if I put it in a RX-7, course then I need a 3.55 final drive ratio, with automatic! RON
yea and it only weights 300 more lbs than an all iron block V8... and about 400 more lbs than a LS1
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Old Jun 20, 2005 | 12:45 AM
  #43  
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not to mention it ill never fit w/o cuttin the whole firewall out and shoving it back 6 inches into it lol....
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Old Jun 20, 2005 | 12:48 AM
  #44  
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underszed turbo and a huge waste gate.
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Old Jun 20, 2005 | 07:30 AM
  #45  
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Originally Posted by Pat McGroin
Yeah, your car definitely needs some reliable American Muscle baby, straight from the powerblock on Spike TV.


The fat Indian dude fromm Horsepower TV,(Chuck Hanson) can do the swap for you in just one HP TV showing.

POWERBLOCK BABY!
Yea in half hour. Also he'll be as clean as before he started touching the car.
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Old Jun 20, 2005 | 07:54 AM
  #46  
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Low end power? So why not just down shift? A good driver should be able to adjust his style to best suit the car. You may not like it. I've never had problems autocrossing and complaining about lack of TQ. Granted I have a TII and this was before I got serious. I have friends with N/A's and with simple mods their cars picked up just as quick as mine before I hit boost. How much low end TQ do you really need?
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Old Jun 20, 2005 | 07:55 AM
  #47  
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Originally Posted by ronbros3
CAN I add to this silliness, I do have this V-12 Jaguar engine would it help if I put it in a RX-7, course then I need a 3.55 final drive ratio, with automatic! RON
GO for it RON. Who the hell needs a V8, when you can have V-12 purr like a kitten.
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Old Jun 20, 2005 | 12:04 PM
  #48  
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my ''4.7'' number was just a guess at whats available... its been a while since I looked into the available options. I know there are a few between 4 to just above 5, thru mazdaspeed/mazdacomp and pillaging other mazda rear ends from other models like their trucks and 929 maybe?

anyhow, its easy to swap out the ring gear on an FC.
1) remove the exhaust and drop the driver side of the rear subframe
2) unbolt the driveshaft from the diff, diff from the subframe and halfshafts from the diff
3) remove the diff (rear end) from the chassis
4) open it up and swap that gear on the back of the differential

of course you really should check the lash and the gear tooth engagement but that is all in the manual, I am only giving you a quick 1-2-3-4 how-to here. most tranny shops can do this gear swap easily if you bring them the parts because the FC's rear end is similar enough to most other rwd cars/trucks that the process is the same concept. make sure you get the right diameter gear for your diff and make sure you get a matching pinion if you need one too. the ring gear swap is a common thing for a rtacecar buildup but not seen too often on streetcars, I think because its not a bling bling part and people are nervous that their mileage will suffer. going from a 4.4 to a 4.9 in my GSR swapped civic, the fuel economy went from 28 to 26, so thats not even a 10% change for the worse.

to swap gears in the tranny, its much more time consuming and delicate, so a ring gear swap is pretty cool for some extra help for acceleration. I dunno if the parts are only available thru mazdacomp and if so you better become a member or find a buddy who is. a heavily modded, lightweight, non-turbo FC is a lot of fun to drive... and a short final drive gear would make it even faster and torquier!
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Old Jun 20, 2005 | 12:16 PM
  #49  
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run the turbo 4 port instead of t he 6 port...
the low end is better on the turbo engines...
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