Differential and strut towers in front of engine?

Does this make for an easier handling fwd setup or more balanced? Does it even really matter that both differential/axles and strut towers sit in front of the engine and transmission?

Are there other fwd setups with that style? The only thing I can think of off the top of my head is the Saab 900 layout and that's not exactly the same since it's longitudal mounted.

You want as much mass within the wheelbase and as evenly spread out to all 4 wheels as possible.. looks like a good design to me..

What kind of car is it?

FWD French cars had the transmission forward of the engine

In Renaults they simply moved the rear engine drive train up front. Citroen always did this too. Take a look at an avant or DS.

I can't tell what is going on in that image, so here is a Mazda K-series V6, turned around backwards so the transmission picks up off of the belts end, and mounted so low and back that the axleshaft goes through the engine valley. Control arms and steering rack mount to the engine and trans as there is no room to put any frame members.

Here's a Volvo.

Production cars generally don't do this because by shoving everything forward, you can get more interior space.

Jumper K. Balls said: In Renaults they simply moved the rear engine drive train up front. Citroen always did this too. Take a look at an avant or DS.

MugenReplica said: Are there other fwd setups with that style? The only thing I can think of off the top of my head is the Saab 900 layout and that's not exactly the same since it's longitudal mounted.

Moving a rear drive train to the front is pretty much what SAAB did too. Looking at the early cars this is easy to see, why they stuck with it for as long as they did, who knows?

I'm not complaining, I love c900s and 99s, but they carry more, not less, mass ahead of the axels than most FWDs. I think an Audi style FWD lay out would have served the 99/900 better.

Back on topic; I think having the gearbox ahead of the engine would have some, but not huge, handling benefits for a high performance FWD, but it wouldn't package well for mass produced models. OTOH, normal transverse FWD power trains mounted in the back makes lots of sense, but sadly not enough people wanted MR2s, Fieros, X1/9s, Scorpions or Consuliers. (Let me know if I missed any)

maybe, but then saab would not have been able to use A arms for the front suspension.

I seem to recall though that GM was experimenting with putting the transmission and diff ahead of the engine in their FWD cars. It was done mostly for handling and some for pedestrian safety as it allowed for more "empty space" in the front of the car. As I have not seen a GM on the road set up that way, I can only imagine they did not bear fruit

Acura Legend/Vigor had longitudinal FWD with a seperate differential that was mounted towards the front of the engine. Made them a right bastard to work on but it got the drivetrain's CG well behind the axle centerline.

I like to point this out but it bears repeating. Pretty much all transverse FWDs have the entirety of the drivetrain ahead of the front axle. Some manufacturers cant the engine very far back to try to help (mainly older VW and S-engined Toyotas) but everything is still way on up there.

Subaru engines weigh practically nothing and thanks to how short they are, they are only about as far forward as a traditional transverse engine is. And almost the entirety of the transmission is behind the axle. The handling downside for Subaru is that boxer engines need to be mounted relatively high for exhaust clearance, unless you do a side exit exhaust like ACVWs.

HappyAndy wrote:

Jumper K. Balls said: In Renaults they simply moved the rear engine drive train up front. Citroen always did this too. Take a look at an avant or DS.

MugenReplica said: Are there other fwd setups with that style? The only thing I can think of off the top of my head is the Saab 900 layout and that's not exactly the same since it's longitudal mounted.

Moving a rear drive train to the front is pretty much what SAAB did too. Looking at the early cars this is easy to see, why they stuck with it for as long as they did, who knows? I'm not complaining, I love c900s and 99s, but they carry more, not less, mass ahead of the axels than most FWDs. I think an Audi style FWD lay out would have served the 99/900 better. Back on topic; I think having the gearbox ahead of the engine would have some, but not huge, handling benefits for a high performance FWD, but it wouldn't package well for mass produced models. OTOH, normal transverse FWD power trains mounted in the back makes lots of sense, but sadly not enough people wanted MR2s, Fieros, X1/9s, Scorpions or Consuliers. (Let me know if I missed any)

Knurled wrote: I can't tell what is going on in that image, so here is a Mazda K-series V6, turned around backwards so the transmission picks up off of the belts end, and mounted so low and back that the axleshaft goes through the engine valley. Control arms and steering rack mount to the engine and trans as there is no room to put any frame members. Here's a Volvo. Production cars generally don't do this because by shoving everything forward, you can get more interior space.

novaderrik wrote: You want as much mass within the wheelbase and as evenly spread out to all 4 wheels as possible.. looks like a good design to me.. What kind of car is it?

Good to know, I understand keeping things in the wheelbase aids in handling. I'd just never saw it quite this way arrangement-wise much less on a 78.8" wheelbase with 3+1 seat arrangement at 2100lbs. Front sussy is simple McPherson and rear is good ol simple twist beam. Caster is over 7 degrees and couple sets of crash bolts can be easily set at -3 camber or more. A lot of suspension items swap from the Yaris. Seems like the biggest problems with the car are CVT trans (FD gears adjustments run up to 5.40), limited horsepower/torque (94/89), next to no front strut options ATM with the upper tie rod perch (maybe retrofit/redampen 02-05 Si struts), and it's banned from some SCCA classes.

It's a Scion/Toyota iQ. After doing a little research it seems quick enough for a non-competitive/fun Sunday cone killer with TRD springs, TRD rear sway, good tires and an alignment.

I had a buddy check Manheim values and you can find one for around $5-$6k in good condition with 40000 miles at auction. I may have to jump on one as a runabout just for the gas mileage and possible fun, low cost project promises it may hold.

In reply to mad_machine:

Years ago I saw a build thread on one of SAAB sites with a 99 using an early Audi Quattro drive line mated to an 8v c900 turbo engine, turned around 180*. The engine sat much lower, and it didn't look like it required radiator relocation. The front suspension was still all SAAB, IDK what they did in the back end. The car was ivory colored and rolling on stock SAAB 14" steelies with dog dish hub caps, you would never guess it wasn't stock by just looking at it with the hood closed.

best I ever saw of a modified C900.. was one made into a mid-rear engine car by simply moving the entire drivetrain to the back of the car.

I can say this.. having pulled the engine/trans out in one piece.. it balances nicely on the cherry picker. You are right that it is a tall package, but It is fairly compact front to rear