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DaewooOfDeath
DaewooOfDeath SuperDork
2/21/17 12:01 a.m.

I'm reading your threads and notice a few themes:

  1. You are all FWD.

  2. You all make silly torque.

  3. You all describe power delivery as violent.

This makes me wonder if you have budget friendly solutions to making traction limited torque monsters with spikey power delivery useful on track/autox. So asks the guy who just experienced third gear wheelspin at a track day.

MrChaos
MrChaos GRM+ Memberand HalfDork
2/21/17 5:54 a.m.

boost limit based on what gear you are in would be my guess.

captdownshift
captdownshift GRM+ Memberand PowerDork
2/21/17 6:03 a.m.

Nathan JansenvanDoorn
Nathan JansenvanDoorn Dork
2/21/17 6:51 a.m.

The throttle has a whole range of positions between open and closed....

If that doesn't work, there are definitely per gear boost solutions that work. Check out some old school turbo dodge (ie: k-car etc) sites. They were VERY creative with this stuff.

On my 2.4t neon, I embraced it. 3rd gear wheel spin in a stock looking neon makes corner workers giggle and point.

jstein77
jstein77 UltraDork
2/21/17 7:29 a.m.

Torsen limited slip FTW.

KyAllroad
KyAllroad UberDork
2/21/17 8:19 a.m.

Stickier tires.

LanEvo
LanEvo GRM+ Memberand Reader
2/21/17 5:25 p.m.

Ok...am I really the only one who has no idea what F2T means?

classicJackets
classicJackets HalfDork
2/21/17 5:28 p.m.
LanEvo wrote: Ok...am I really the only one who has no idea what F2T means?

Nope, I'm right there with you

Stefan
Stefan GRM+ Memberand MegaDork
2/21/17 5:30 p.m.

Its a turbocharged 4-cylinder FWD engine produced by Mazda and its known for easily driving very large turbos and large amount of boost. Its similar to the Chrysler 2.2/2.5L SOHC turbo motors in so much as they weren't terribly sophisticated, but tough as nails and could swallow a ton of boost pretty reliably.

Of course the drawback to using a huge turbo on a 4-cylinder is that the power curve can be pretty insane, leading to lovely amounts of torque steer in a FWD vehicle.

Mazda F2T on Wikipedia

codrus
codrus GRM+ Memberand SuperDork
2/21/17 5:30 p.m.

I believe It's a Mazda 4-cylinder piston engine, older than the BP in the Miata, which was often used with turbos in cars like the first gen MX-6 and Probe.

mndsm
mndsm MegaDork
2/21/17 5:35 p.m.

We wait for the transmissions to blow up. That's how we limit torque.

pres589
pres589 PowerDork
2/21/17 5:46 p.m.

It's also based on an older diesel motor and filled with really high quality parts. It's not really great to listen to and it's not especially light. They're also attached to some crappy transmissions unless someone with some skills wants to engineer away that situation. They also bolt up to some RWD Mazda transmissions.

These cars had torque steer issues with the small factory turbo. And the transmissions aren't really overbuilt for the factory power levels.

I kind of want one in my Capri. And a lot of other things for my Capri to happen magically but this would be a great engine for that kind of car; rear wheel drive, solid rear axle, small and light weight.

DaewooOfDeath
DaewooOfDeath SuperDork
2/21/17 10:45 p.m.

I don't have an F2T, but it seems like the most extreme version of what I do have, a big turbo on an fwd with lots of torque.

I just dynod my turbo beta (2.0 dohc Hyundai thing) at 262 whp and 285 wtq. It hits hard at about 4k rpm and I shift at 6800.

Last trackday was super fun, but I was probably peddling the thing half of the lap.

Part of that is crappy tires, but I wonder how much I can get away with before lsd. I'd like to avoid lsd because I've heard it ruins turn in.

That said, my 262 whp was on a conservative 87 octane tune and the turbo will supposedly support over 400 whp ...

Not sure how long I'll be resisting that particular temptation.

KyAllroad
KyAllroad UberDork
2/22/17 6:03 a.m.

In reply to

Wait, "bolts to some RWD transmissions". Does that mean there are F2T/Miata swaps out there?

captdownshift
captdownshift GRM+ Memberand PowerDork
2/22/17 6:04 a.m.

In reply to DaewooOfDeath:

go slap whoever suggested to you that a limited slip will ruin turn in.

captdownshift
captdownshift GRM+ Memberand PowerDork
2/22/17 6:10 a.m.

Also, not GRM price friendly, but the answer to all your massive torque gearbox implosion concerns from your F2T.

Sometimes it's just easier to drop more then what you have in the car into the gearbox so that you never have to worry about it again. The expense of having to change the fluid with every oil change is the only really pain.

DaewooOfDeath
DaewooOfDeath SuperDork
2/22/17 6:38 a.m.
captdownshift wrote: In reply to DaewooOfDeath: go slap whoever suggested to you that a limited slip will ruin turn in.

Uh, Lotus told me that.

http://www.lotustalk.com/forums/f3/lsd-vs-open-diff-better-track-27049/

It was also something some pretty high level autocrossers mentioned with regards to their cars.

http://www.mr2oc.com/45-auto-x/298272-sts2-mk1-suspension-setup-w-host-xhead.html

Is it different for FWD cars?

bentwrench
bentwrench Dork
2/22/17 6:54 a.m.

Everything is different for FWD. Often backwards!

Take everything you thought you knew about cars RWD and throw it away. You have transitioned to the FWD zone, and things are not what they seem to be. Even driving technique is different, just huck it into a corner, if it tries to swap ends add power!

Vigo
Vigo PowerDork
2/22/17 7:06 a.m.

Admittedly i don't have time to open those links right now, but one thing to keep in mind is that RWD platforms often use pre-loaded clutch type limited slips that start fighting back as soon as the wheel speeds change, even under decel. FWDs basically cant use those and typically use a helical gear or Torsen type diffs that are literally doing nothing until the wheels are turning different speeds AND under power. So if you turn in under deceleration they would have next to no effect.

rslifkin
rslifkin Dork
2/22/17 8:07 a.m.

Vigo is right. The more pre-load an LSD has, the more it'll do off-throttle and the more it'll hurt turn-in. An LSD with little to no preload is basically open until you get on the throttle, so it won't really affect turn-in when you're off the throttle.

pres589
pres589 PowerDork
2/22/17 10:03 a.m.

In reply to KyAllroad:

I'm not the fountain of knowledge that others are on this, but, basically the B2200 bellhousing and trans can be used to make a RWD something. I don't think there's anything special at all required to do this. Note that putting it in a B-series truck will put the F2T distributor through the factory firewall. Lots to look up there. This does not give a ton of room for a big clutch which may be an issue at higher power levels.

The B2600 that used the Mazda G6 engine is supposed to be a bellhousing donor that allows for a bigger flywheel and clutch. This will bolt to the truck manual transmissions as well as RX-7 units. I don't know if the FD manual is included in that list of boxes; the FC TurboII box is a popular unit but I don't know how easy those are to find anymore.

I don't think there's an easy way to attach this thing to the gearbox in the MX-5's. Probably best to just find one of the existing bolt-together setups and go that route. Challenges would be the overall height of the thing, the previously mentioned distributor and how to deal with removing that thing, and where the throttle body ends up. On the B-truck, one solution is to turn the top half of the intake around which points the trottle body ahead and near the back of the passenger side headlight. A new longer throttle cable is required but it otherwise works. MX-5 may not work out so nicely.

For front wheel drive, the Toyota E153 box out of the Solara or mk2 MR2 has been mated up to the F2T. I don't know of any other solutions have been tried.

GameboyRMH
GameboyRMH GRM+ Memberand MegaDork
2/22/17 10:08 a.m.

For FWD cars that need to turn corners, a gear-type LSD is best. These have no negative effects on handling at all - it's like an open diff, just without the one-wheel-peeling. Wavetrac makes a gear-type LSD that can preload itself to prevent one-wheel-peeling even if there's little to no traction at one wheel.

JamesMcD
JamesMcD SuperDork
2/22/17 10:18 a.m.

There are a few FE3 (16v version of F2) into Miata swaps out there.

You take the front housing off the B2000/B2200 trans and attach it to a Miata trans, then you have a transmission that attaches to the Miata PPF, and also attaches to a F-series motor. The motor mounts needed to attach to a Miata are custom.

For putting the F2T into a truck, there are Mazda parts "out there" to relocate the distributor to the front of the motor.

pres589
pres589 PowerDork
2/22/17 11:25 a.m.

In reply to JamesMcD:

Yeah, the head off the Bongo. But at this point, I think I'd rather just work on removing the distributor entirely, and run Megasquirt and coil near plug. Takes care of the distributor hitting the wall issue, allows for removal of the vane-type MAF, allows for all the other nice tuning that MS brings to the table.

Ian F
Ian F MegaDork
2/22/17 11:57 a.m.

More tire?

No F2T here (still not sure what that means...), but after experiencing a well-modded Mk IV GTI 1.8T with 285 section A6's up front and an aftermarket LSD, I just know I want one.

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