Anybody worried about the powertrain swaps in FM4?

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I used to have a '90 Eagle Talon AWD turbo. Great car. When I got it, it averaged 21 mpg. After the mods it averaged 25 mpg. Nice thing about hopping up turbos is the gas mileage improves.

If you want to do a swap the main goal would to put the drivetrain into a lighter car than you pulled it out of. I seriously considered putting a FWD Diamond Star turbo in the rear of a 80-83 Toyota Starlet. They are very light (aprox. 1750 lbs) front engine/rear wheel drive cars so you wouldn't have to mess with the front suspension. To be honest, the advantage of the AWD to the FWD Diamond Stars is off the line traction. The FWD's get better gas milage and faster mph 1/4 mile speeds because of less drivetrain drag and lighter weight. I'm talking mph at the end of the 1/4, not E.T. Plus the FWD's shift better than the AWD's. You put the FWD engine in the back of a light car and you have the best of both worlds. The Diamond Star trans. is operated by two cables so all you need is longer cables.

AWD isn't necessarily the best way to go. If you have the engine over the rear driven wheels, as long as the front to rear weight balance isn't too far off and the hp isn't extreme then RWD can be lighter with less drivetrain power loss, both of which makes it faster and increases gas mileage.
 
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If you want to do a swap the main goal would to put the drivetrain into a lighter car than you pulled it out of. I seriously considered putting a FWD Diamond Star turbo in the rear of a 80-83 Toyota Starlet. They are very light (aprox. 1750 lbs) front engine/rear wheel drive cars so you wouldn't have to mess with the front suspension. To be honest, the advantage of the AWD to the FWD Diamond Stars is off the line traction. The FWD's get better gas milage and faster mph 1/4 mile speeds because of less drivetrain drag and lighter weight. I'm talking mph at the end of the 1/4, not E.T. Plus the FWD's shift better than the AWD's. You put the FWD engine in the back of a light car and you have the best of both worlds. The Diamond Star trans. is operated by two cables so all you need is longer cables.
That's still besides the point. The main idea is to take the Starlet (for example) and create an AWD Starlet. To do so, you'd probably have to alter the whole front suspension setup and maybe even tubeframe the front to somehow cram the front differential into the frame... Swapping stuff back and forth is one thing, but turning a RWD or FWD car into AWD is something completely different.

AWD isn't necessarily the best way to go. If you have the engine over the rear driven wheels, as long as the front to rear weight balance isn't too far off and the hp isn't extreme then RWD can be lighter with less drivetrain power loss, both of which makes it faster and increases gas mileage.
AWD is, of course, not always advantageous. The problem isn't the AWD swaps itself, it's how Forza's PI system doesn't take the benefits of the swap into account, thereby creating a decent advantage in terms of PI for AWD swapped cars - and some cars that come with AWD from the factory.
 
As far as drive train swaps go, I'm neutral. It's nice to have the possibility to take a nice FWD car and turn it into something with RWD or AWD, so I think it's a neat feature, even though it should cost huge amounts of credits and probably not be available on so many cars. Stuff like that is very costly and rare in the real world, but I guess it's cool if there's no favourable swap that gives you a massive advantage with the PI system (which is the true culprit here, in my opinion).

I was replying to this comment...if it's rare and costly depends.

That's still besides the point. The main idea is to take the Starlet (for example) and create an AWD Starlet. To do so, you'd probably have to alter the whole front suspension setup and maybe even tubeframe the front to somehow cram the front differential into the frame... Swapping stuff back and forth is one thing, but turning a RWD or FWD car into AWD is something completely different.

I thought the main idea is to make a car fast. I was trying to point out that in real life people have been making swaps for over 70 years. It's not rocket science. AWD just takes longer to do, and weighs more. For the most part, in real life racing AWD is mostly used in dirt or snow. The reason is, it's not worth the trouble over RWD on pavement, all things considered.

I will also add that building cars now is easier than it's ever been. If you go to Glamis, California on any winter weekend you will see hundreds of buggies that were built by the guy driving it (almost all are RWD). There are dozens of web sites detailing steering geometry and frame construction. Many of the welders put out by China are dirt cheap and terrific. Just about any part you can think of can be bought online with a credit card.
 
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Engine and Drivetrain swaps are my favorite part of the Forza series. Its what truly sets this game apart from the other sim racers.

One vehicle I can almost guarantee that will be a leaderboard vehicle is the GMC Syclone. I imagine we will be able to swap in some very high HP engines into that little truck. Probably the stock car engines too. 1,000 hp in that little truck will probably be the Datson all over again. Regardless, its going to be VERY fast and I imagine they will allow for a RWD swap. 👍
 
I for one will be keeping the 4.3L V6 thankyou very much.:D
One car in FM3 I HAD to swap an engine for was the Datsun 240Z. They put some crummy 4cyl version in the game, and to me the 240Z can be nothing but 6cyl, so I used the 3.7L V6 in it.
 
Engine and Drivetrain swaps are my favorite part of the Forza series. Its what truly sets this game apart from the other sim racers.

One vehicle I can almost guarantee that will be a leaderboard vehicle is the GMC Syclone. I imagine we will be able to swap in some very high HP engines into that little truck. Probably the stock car engines too. 1,000 hp in that little truck will probably be the Datson all over again. Regardless, its going to be VERY fast and I imagine they will allow for a RWD swap. 👍

Maybe for the drag leaderboards, but can't see it being competitive on circuits
 
In the case of Forza, this mean swapping the drivetrain from a Ford RS200 into into a Mustang to create an all-wheel driven Mustang... Or an Eagle Talon's AWD drivetrain into a Viper SRT-10 ACR.

I'm unsure why people think an AWD viper is so absurd. I've always assumed the drivetrain came from the AWD Charger (scroll down the page to see the drivetrain) which would more than be up for the job and would fit with relative ease. The Mustang drivetrain is also probably from some other AWD ford (Cossie?) as the RS200 is a mid-engine car, that just wouldn't work with the standard Mustang engine location.

None of this is impossible.

Of all the FM3 drivetrain conversions I think I only found one that wasn't feasible (from the info I could find) are the AWD MR2 and MRS's. Toyota has never made a Rear-mid engine AWD transmission AFAIK Aside from some MR2 rally monstrosity.
 
Exactly. AWD swaps are feasible.

For the most part, in real life racing AWD is mostly used in dirt or snow

True, but for the most part this is because it has been banned in most pavement/grip racing classes as it is, infact, advantageous.

Indeed, the incredible 4wd system we see now from Ferrari in the FF is infact a still-born system from the 80's that was being developed for F1.
 
I'm unsure why people think an AWD viper is so absurd. I've always assumed the drivetrain came from the AWD Charger (scroll down the page to see the drivetrain) which would more than be up for the job and would fit with relative ease. The Mustang drivetrain is also probably from some other AWD ford (Cossie?) as the RS200 is a mid-engine car, that just wouldn't work with the standard Mustang engine location.
You can discern the car that donated the AWD drivetrain by looking at the gearbox, for example. Looking at the gearbox after swapping the Ford to AWD, it has the exact same gearbox as a stock RS200.

As for the Charger, that wasn't even out when Forza 3 launched. Also, the gearbox suggests that it's from the Talon indeed.

None of this is impossible.
No, it wouldn't be impossible. The way the swaps are handled in FM3, though, seems rather impossible. Which isn't tge big deal, though. I'll get to that later.

Of all the FM3 drivetrain conversions I think I only found one that wasn't feasible (from the info I could find) are the AWD MR2 and MRS's. Toyota has never made a Rear-mid engine AWD transmission AFAIK Aside from some MR2 rally monstrosity.
Porsche, for example, never made an AWD mid engine drivetrain. Yet, you can swap the Porsche Carrera GT to AWD.
Mercedes never made an AWD mid engine drivetrain, either. Not to my knowledge, at least. And yet, you can swap the CLK GTR to AWD.

I think you can see where this is going.
Exactly. AWD swaps are feasible.
The point isn't the feasability. Even though some of the swaps don't seem feasible the way FM3 handles swapping stuff in general.

The point is that the AWD swaps create a massive advantage with the PI system. As ffar as I am concerned, people could drive AWD Vipers, AWD CLK GTRs and AWD Porsche Carrera GTs forever. The only problem I'm having with that is that doing so gives them an advantage ovver people who like their cars to be RWD.

And before you try to argue about the supremacy of AWD: That is what the PI system is supposed to prevent. Instead, it amplifies it - or it did so in FM3, at least. From what I've seen, there are aa few clues that lead me to think that they've fixed it now. But I've still got my fingers crossed.
 
I'm unsure why people think an AWD viper is so absurd. I've always assumed the drivetrain came from the AWD Charger (scroll down the page to see the drivetrain) which would more than be up for the job and would fit with relative ease.
The problem is that the engine position in the Viper would not allow it.
Here's why: The Viper uses a 90° V10, and the engine sits very low in the car. There would be no way to connect the front wheels with a driveshaft because the bottom of the engine sits right across the plane that would be drawn between the front wheels. You physically could not connect a driveshaft between the front wheels without it running through the crankshaft.
To solve this problem, you could raise the engine. You would have to raise it about 8 inches (and that's if you want non-equal length driveshafts with an offset front differential) This would require a whole new front end, and would DRASTICALLY change the handling characteristics of the car. Plus it would look nothing like a Viper from the windshield forward.
The other option would be to have the front wheels driven by belts or chains that are split from a differential behind the engine, and run up to some sort of heim joint type device that would allow the wheels to turn and still be driven. And that seems totally realistic and safe to use on a race car.


On Topic: I really, really hope that AWD and RWD can be balanced in FM4. I haven't driven an AWD car in FM3 in like 18 months because they're just stupid. There's no performance correlation between them and RWD cars. Basically, PI works within a drive type, but not across them (i.e. A600 AWDs are all fairly close, A600 RWDs are fairly close, but A600 AWD vs A600 RWD :lol::lol::lol:)
 
With enough money, anything is possible.

I'd actually like it if T10 priced the drivetrain and engine swaps very high to the point people would question whether to do them or not. Doing an engine, or ESPECIALLY a drivetrain swap, is very expensive. I never got that feeling with most cars in FM3 with the swaps though
 
With enough money, anything is possible.

I'd actually like it if T10 priced the drivetrain and engine swaps very high to the point people would question whether to do them or not. Doing an engine, or ESPECIALLY a drivetrain swap, is very expensive. I never got that feeling with most cars in FM3 with the swaps though
For drivetrain swaps, I agree. However, as for the engine swaps, some should be expensive, some shouldn't. There are some engine swaps that are fairly easy and cheap to make, and some that take a huge amount of work that should be insanely pricey.

Then again, who cares about paying a few hundred thousand credits in FM to get a competitive car? Also, with the manufacturer affinity, you'll be able to get free upgrades, either way.
 
The problem is that the engine position in the Viper would not allow it.
Here's why: The Viper uses a 90° V10, and the engine sits very low in the car. There would be no way to connect the front wheels with a driveshaft because the bottom of the engine sits right across the plane that would be drawn between the front wheels. You physically could not connect a driveshaft between the front wheels without it running through the crankshaft.
To solve this problem, you could raise the engine. You would have to raise it about 8 inches (and that's if you want non-equal length driveshafts with an offset front differential) This would require a whole new front end, and would DRASTICALLY change the handling characteristics of the car. Plus it would look nothing like a Viper from the windshield forward.

No need to move the engine vertically at all from what I can see, not by eight inches at least. The Viper is a Front-mid engine car, the engine is so far back in the engine bay the driveshafts will fit in front of the crank pulley. As seen here by noting the position of the wheels below and by positioning the D/shafts parallel to the strut brace which has good clearance of the engine as is.

bat-viper.side.jpg

Yes that was/is a Viper :lol:

If any thing you may need to move the engine back by a few inches and if absolutely necessary up by the same amount. Custom engine & G/box mountings would do the trick. No real body mods to speak of, it will still look 100% viper. Now All that would need doing is mounting the front differential and modifying the front chassis uprights for the D/shafts, nothing a decent engineer, machinist and fabricator wouldn't be able to figure out between the three of them. This should be even easier on a GTS-R Viper or competition Coupe because of the spaceframe chassis they have.

Sorry for the off-topic guys :mischievous:

The on topic part// I'm glad T10 didn't scrap the FM3 PI model but continued to build upon it like they have, this was key to a better model. The same thing bugged me about the Mclaren F1 team, if they assign another brand new car to the junkyard for the third year running, I'll be convinced nobody there knows what they're doing and will start supporting Ferrari.. Ok, that was one step too far lol Ultimately though, until we all give it a good bug test we'll not know how well the modifications have worked.
 
Glad to see they have noticed the problems with AWD in FM3, and by the sounds of it sorted it according to FM.net.

This sounds like great news
 
With enough money, anything is possible.

I'd actually like it if T10 priced the drivetrain and engine swaps very high to the point people would question whether to do them or not. Doing an engine, or ESPECIALLY a drivetrain swap, is very expensive. I never got that feeling with most cars in FM3 with the swaps though

Well, I think it should depend on whether or not the engine is easy to find or not. If it's something like an SR20DETT from an S13, then it should be a great deal cheaper then the V8 from an R390. I think I remember in FM3 they were all priced at 10,000. Which presuming most of the work in the game is done by the player itself, should only be the case for a mid range engine.

SR20DETT- 3,000
RB25-8,000
VR38DETT-15,000
R390 V8-40,000
 
High pricing drive train swaps to put off potential fast cars would only widen the gap.

The poor sods who couldn't afford them would get trumped and earn no cash.
 
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