Just another crazy hybrid idea

[Guest thevodka]

I have a feeling I'll be told that I'm some sort of crazy cook or wild dreamer with no realistic sense of cost, but here it goes, my idea for my dream Z, which I hope to start working on as soon as I come into more money.

 

When I saw someone try to mount a FC-age 13B Single Turbo, I had thought that the motor, with its size, could be used in a mid-engine capacity. Unfortunately, I had thought that the idea would compromise the weight distribution. What I came up with is a rather crazy idea of converting the car into a convertible sans actual top, which I know may have structural rigidity issues as I want the car as a track car, but I thought that a custom roll-cage setup and suspension mods might resolve some, if not all of that. On top of that, other weight-saving measures such as moving a fuel cell and keeping the battery in the front would be utilized, as well as some ligher-than-stock parts on the rear (TBD) and hopefully front to try to keep the weight down. My next concern was air induction into the engine bay, to both cool and help prevent heat soak. What I had thought up of was a custom hood with small (or one large) reverse hood scoops, kinda basing the idea off an MR2, and mounting the IC & Radiator near the scoops to force air into them. I had thought of this idea before coming to this forum, and then I find out that someone had thought up of this in a thread about rear-mounting a motor. I was also wondering if a 2+2 would be more useful in this application due to its longer chassis length?

 

BTW, whatever engine I get in my future Z project, I hope to stick around here for awhile, as this is a really interesting forum.

[auxilary]

I'm the rotary Z guy. I wouldn't do a rear (mid) engined rotary Z for the same reason you're concerned about: weight distribution. My engine mount already makes it a mid engined car, the engine's far behind the front axle, and it literally sits almost in the middle. I wanted to keep it as far forward as possible to retain some weight over the front wheels. I'm going to try to retain the battery up front too, but not in the stock location (too much heat).

 

http://www.rotaryz.com/gallery

[johnc]

If you look at that layout of most mid-engined cars, they have something called a "cab forward design" which essentially makes room for the engine behind the driver. I, for the life of me, can't see enough room behind the driver/passenger area in a 240Z (even a 2+2 280Z) for an engine, transmission, and driveshaft. You might be able to put the engine and transmisison where the passenger footwell and seat are.

[auxilary]

that's the other reason: you're have to run forward mounted transmission with a rotary, if anything, to make it fit. The seats in the Z are almost on the rear axle. You could make a rear engine car out of it... wheelie monster!

 

great, I just thought of another project: worked 1608cc bug engine into a rear of a Z! ha!

[Chewievette]

I, for the life of me, can't see enough room behind the driver/passenger area in a 240Z (even a 2+2 280Z) for an engine, transmission, and driveshaft. You might be able to put the engine and transmisison where the passenger footwell and seat are.

Engine and Transaxle VS Engine, Transmission, Clutch, Differential, and Driveshaft. A transaxle saves quite a bit of room. a 2+2 might have just enough room to do this kind of thing. Just remember that you'll be modifying just about everything in the car. Definately NOT a weekend project. If weight is your concern, Move the fuel tank and spare tire to the front and if possible move the battery even farther foreward. I'm sure it can be done, it'll just take more time and calculations than a regular swap. If you want to learn all you ever wanted to know and More about weight distribution, read up on Aircraft weight and balance, for aircraft this is critical. With the correct formulas and calculations you can still get a 50/50 distribution.

[Gollum]

wat about using a transaxle such as the G-50 porshe tranny. It can handle about 700hp 600hp no sweat and it would put the engine as far back as you can get it. The ultima kit from england (just beat mclaren's factory guiness record) and factory five kit in development both use this tranny. It's something to look into.

 

http://www.ultimacars.com/

 

http://factoryfive.com/table/ffrkits/GTM/gtmprototype.html

[ZROSSA]

You could use the trans out of any front wheel drive car that has the engine mounted north south. Audi 5000, Renualt 25 , cx citroen and maybe the easiest olds toranado with a big block.

 

Douglas

[JMortensen]

If you mounted the engine behind the driver the weight distribution would be really severely screwed IMO. You'd end up with possibly worse than 911 distribution. Basically driving the car would be like throwing a dart backwards, and as soon as you started to get a little sideways the heavy end would want to go to the front. I gotta agree with Alex that mid engine a la S2000 (front midengine) is the way to go in a Z, rear mid engine is going to be a problem.

[BrandonsZ]

GOLLUM

 

0-100-0 in 10.4 seconds is quite impressive, but they have a 600+hp chevy V8 in that bad boy.

 

They should make the requirement 0-100-0 on a banked oval so you have to factor in side force as well.

[Gollum]

well brandon, at least the test is standardized. It's the same company that tested the mclaren.

 

Oh yea, the mclaten has a 650hp V12.

 

It should also be noted that mclaren himself used the ultima kit to test his drivetrain and basically built his chassis around many of the principles that makes the ultima so fast. Not saying that the mclaren is a piece of stolen technology, but rather mclarens ideas didn't come from nowhere. I'm sure the ultima ranks high in his inspiriations.

[Chewievette]

The largest problem with getting the weight distribution correct in a Z car is YOU!!! The driver location in a Z is specifically designed for THIS platform! If you go an put the engine in back your going to screw all that up! If you want a high performance mid engined car that handles well on a road coarse, BUY ONE!! Your going to have to pick between which form and function combo you like better. It takes some serious engineering to put a mid engine in a front engine car. The only way this will work with the driver position is one of two ways. A VERY heavy car, it'll take a LOT of ballast to counterweight the driver AND drivetrain! Or you can move the driver. You want a 'cab foreward' layout in a mid engined car, its the only way to get the driver far enough foreward. Now, if this was me... I would stick with the front engine you'll give yourself far less grief. With a properly setup front engine car you can match if not beat a mid engined car. In this case the only thing a mid engine car would have over you is weight, namely the lack of driveshaft. But I will temper my response with is, if you are truely committed to this project and have a ton of money that you'd like to get rid of, GO FOR IT!! I'd love to see the thing when you get it done!

[Guest thevodka]

Don't worry, I've already settled on getting a Front-Engine configuration, and the likelyhood is right now the LS1, but I'm still considering the 1jz-gte and the 1uz 4.0 Lexus engine

[johnc]

The largest problem with getting the weight distribution correct in a Z car

 

Time to get on my soapbox again, and Chewievette, I'm not picking on you or your statement...

 

Any 240Z longitudinal weight distribution in the range of 56F/44R or 44F/56R can be made to handle pretty well. Weight distribution is not the end-all that many magazines make it out to be, for example: an Acura Integra Type R is a very good handling vehicle and its weight distribution is 63F/37R.

 

Don't focus on the numbers. Tire and wheel sizing, spring rates, anti-roll bar rates, shock adjustment, track width, alignement, etc. can all be used to tune even bizzarre weight distibutions.

[DavyZ]

John,

 

I take it that it is the novelty of having something completely different that makes you interested in doign this? I know you are extremely capable of making nearly anything handle well, let alone being able to fabricate a racecar from scratch, but why not do a JTR-type aluminum-block V8 Z with a 6 speed or something like that? Is this a class restricted car you are toying with building? You peak my interest with this thread.

 

Davy

[johnc]

Davy,

 

Was that reply directed at me? If so, I'm not building the car, just offering some suggestions. If not, to quote Emily Lattella, "Never mind."

[Gollum]

johnc is a wise one indeed.

 

although, it should be noted that for drifting or rally racing weight distrobution is what your car's set up revolves around. You need a good place to start and then make everything else compliment that setup.

 

I agree that a FR set up can be just as fast and even faster than a MR setup. Personally I like the FR setup better because it lends itself to better all around performance. A MR car is really made for one thing, citcut racing. It's ok for drag but you don't have the room for a great drag suspention setup. Top fuel cars layout works because they don't use rear suspension that's funcional. It's all in the tires for them. A FR car cas great low speed turning, awsome street drivability and it's much more novice friendly on the track. The fact that a FR can be as fast as a MR is all the more reason that FR is a powerful setup.

 

Note: MR cars really start to shine in very small compact formats. The MR-S is an awomse car that can take mountain passes like a real champ once fitted with some extra ponies and a good suspention with good play that's not too soft. But, small MR cars like the MR-S don't lend themselves too well to tracks like Fuji (short for full name that escapes me), tracks where high speed cornering is crucial. Now, a large MR car like a ferrari won't handle on tight mountain type hiarpins but it will take a huge fat 4 lane hairpin at 90mph and say "what turn." So you begin to see that charictaristics of a MR car. Not to say they're not any good or such obsticals can't be overcome, it's just that this is the way they start and you have to work from there.

 

Sorry to make such a long and pointless post. But if anyone learns something i'll be more than happy.

 

Hope all goes well thevodka

[Guest 240zJake]

Well, you gotta remember, f-1 cars are MR and they bitch slap those corners...

[Gollum]

i'd like to see an F1 car drift a 20mph turn. Cuz they don't. They slow down to minimal speeds and bank on grip on the exit. A good street/track car could drift through the same turn at around the same speed and have better exit line to use the track more. Although this eats up tires, it's the optimal line, and the only way to hit it.

 

American driving (i think) is too focused on endurance. I'd like to see american races be brought down to (on average) 30 minutes max. This would really make the cars go all out. We would see faster lap times and more fierce competition.

 

Another thing to remember is that F1 cars ARE the turning machine. They actually don't have many course top speeds, but have best lap times everywhere for thier ability to hit the apex and stay there as directed.

 

Peronally, i think some people are too focused on making a fast car. What many people don't realise is that a truly fast car isn't fun to drive. In other words, the best setup isn't fun. But, a true street driven race car will be fun to drive and maintain as much speed as it can muster. This is the reason i'm not really into drag racing. I've been around it all my life and at the end of the day i just simply can't respect them because they're (usually) not all around cars.

 

I want a car that is predictable, gives me great road responce, has good play in the suspension, has high speed stability, and has good all around balance.

 

Now, why do you think the old 80's FR carollas are world known? Because they where a simplistic, fun to drive, well balanced car. With good tuning they're still one of the fastest cars you can get for turning.

 

Now... anyone who's spent way too many hours playing gran turismo, what car do you have the most fun driving? For me it's one of the fallowing. ZZll, Lotus Espirit, Rx7 RZ, WRX (can't remeber model... spec c?), and AE86 trueno.

 

Cars that at first I thought I'd love i actually didn't end up liking. Like the supra.... It's so hard to find a good balance of power, because with too much power the back end floats around too much. It's a very hard car to tune well. The viper is one boat to drive. It's near impossible to turn in unless you have massive brake-oversteer. The cars that really grabbed my attention I usually tried out of boredom, like the Rx7. I had owned one before, but never really got a feel for it. I bought one and set it up with multiple HP options. And I found that I could tune the car with any tires and keep it controlible and fun, even with simulation tires. And there are cars like the AE86. Take one lap on complex steering and the hill turns are SO thrilling. The car slides into the turns as if driving for you. And it's turn in acceleration is so addicting.

 

Now, after having fun with you favorite cars to drive in GT3 go drive a F1 car... was it fun? Personally, I think they're too point shoot based. With thier long narrow stance they rely on early braking and good lead in before throttle. If you have a banked turn lift can cause spin outs, so if you come in too fast it's very hard to adjust. A well balanced street car won't have that problem. A good tune should give the driver a nice cushion.

 

Anyhoo, i'm gonna stop all this nonsence. Most people probly know this stuff.

[Chewievette]

Wow, I just read all that... Now that's scary! Anyways, I do understand about your point of weight distribution isn't everything. but from my experience its much easier to setup a nice manered well balanced car by getting the weight right first. and since it's really not that hard to do, I usually point that out first. But since it seems no one is acctually going to do this its a bit of a mute point. I'd be tempted to try it, if it wasn't for the fact that I already have three projects lined up and I dont need another.

[Gollum]

true, this is kinda a dead horse since nobody is gonna do it. Personally, i'll leave MR cars to comapanies to engineer.