twint78

well ive had a stock fd

a t78 fd

now i have a v8 fd

thoughts on something new and different and not done b4.

a 3 rotor rear mid engine layout?what would it take.

who could enlighten me on this?

this car would totally made for track use.so reliability is no longer a factor.

ive seen mva's new dyno numbers and ive been hardup on these dyno sheets lately. plus ive been missing my turbos and airplane sounds and feels.

should i swap in maybe like fiero or mr2 rear end or use it as a base build?

thanx in advance?

BlackR1

i've seen mid engine 12A's...but i think 20B or even the 13B-REW are far too big for most regular mid engine car shells. Might be able to get a 13B into a Fiero, but that's a hell of a lot of work.

just buy a lotus esprit v8-- it'll cost about the same.

twint78

no one is talking about dropping a 20b into a fiero.

reread the post please.

i speak of using a acura nsx or mr2 layout.cutting the whole rearend out.putting a 20b sideways.shoving the gas tank upfront.

i would want to use maybe like a clutchless shifting tranmission for the project.

what i am asking is maybe swapping another rear end in to be able to produce this product and layout.

things involved.

thanx

wingsfan

Well, if you are looking at something as spendy as an NSX, You might be able to drop a 20B into an old Porsche 911 shell. Those flat 6's are pretty big. I think that they are more wide than tall, so fitment might take some work. You might be able to steal some of the design from a DSM (eclipse, talon, etc) and fabricate a setup so that the 20 B mounts in at 90º to the driveshaft. You might even be able to retain AWD, although I don't think Porsche offered AWD in their 911 until 1996, and that would be spendy. otherwise all the 911 series are rear engined and RWD.

Sounds interesting. You'd have a pretty cool car when you're done.

twint78

not hearing me.

i said a mid engine 3rd gen rx7.rx7 being keyword ppl.the only thing i brought up about nsx is cutting out the fd's and swapping in a nsx rear end assembly or fabricate a new one.

yknow what nevermind moderator can just delete this post.ill look to other info and forums.

CCarlisi

https://www.rx7club.com/forum/showth...threadid=84128

I've been thinking about the same thing for awhile. Here is my photoshop rendition of a rear/mid engine FD. I really like the sound and torque of the 20B. Since it is not a simple drop in swap for the FD I think it's worth considering other platforms.

First look at the inherent limitations of the FD. One of the biggest is the lack of traction. This can be solved by using larger rear wheels, but that in itself requires a bunch of other modifications (pettit flares, coilovers ect).
With the traction problem solved, you have to then look at the effect on handling. I have no personal experience with this, but I imagine running 285 in the front (which is what I undestand the max size to be) with 315s in the rear, coupled with the additional weight of the 20B in the front will give the car more pronounced understeer. This concerns me because the FDs handling is what I think really distinguishes it from other cars.

By contrast if you start with a car that has a lot of weight over the rear axle, large rear tires won't upset the balance because it will need them to sustain the same lateral loads as the front with narrower tires.

The second problem is cooling. It is hard enough to cool a highly stressed 13B with the limited frontal area of the FD. This will be more difficult when using a motor that is 30% larger, assuming it is subject to the same level of stress. One solution is to dial down the boost, but then you're reducing the efficiency of the motor relative to the 13B and defeating the purpose of installing a 20B.

With a mid or rear engined car the radiator is still in the front, so you can vent the hood to pull air through it. In addition, you can vent the engine compartment cover and use the low pressure airflow coming off the back of the car to pull hot air out of the engine compartment. The venting can also be much more aggressive than with a front engine car without looking unsightly (vented engine compartments are cool-think F40....vented front hoods conjure up thoughts of hoodless 50s muscle cars

Finally the FD has many shortcomings unrelated to the motor that become more prounounced when the car is pushed beyond the design envelop. The brakes, shocks, and aerodynamics need to be uprated. The interior (leather, trim, features), the exterior paint and wheels are not strong points of the car. They're tolerable for a car of its cost, but when you invest the money necessary to do a 20b conversion they are harder to accept. Any money spent to correct this stuff is basically lost on resale.

SOLUTION(S):
Porsche: 996 or 986(boxter) I think both would be great starting points. You can get a used boxter for mid 20s these days. I bet if you were patient you could pick up one w motor problems in the teens(have a friend that works at a porsche dealer on the lookout for one). A boxter replacement motor is around 20k, so I imagine the cost would go down significantly for one with a blown motor. Alternately you could buy a working car and sell the motor.

You're starting with German paint, leather, brakes and quality. The car is very well sorted from the factory. You could focus your efforts principally on the engine swap itself.
The same goes for the 996. This might be an even easier car to put the motor in since it sits behind the axle. if you need a little more length, you could modify the bumper reinforcement ect. Also you don't have to worry about the height of the engine compartment as much (although I've seen the watercooled 6s on engine stands and they're not that small/low). As someone pointed out in this thread, you could even put in or start with 4 wheel drive. This would surely end the traction problems. The car would handle better than a 996 as well assuming the motor is lighter.

And last but not least you'd have a PORSCHE. I don't care what people say (and I love the way the fd looks) either porsche is more exotic and more impressive to the laywoman. I think you would have better resale value as well. People are used to paying 40k for a porsche. The cost would still be below the new purchase price of either car. Thefore buying one with more hp than a modded 996 turbo with a non porsche motor would be an easier pill to swallow than buying a 10 year old mazda that costs the same.

I also really like the lotus esprit, but they have so many problems and are much harder to get parts for. The engine compartment in the NSX is extremely cramped. If you rip out the rear trunk that might help, but I think it would be more difficult than going with a porsche. Also I believe it would be much easier to get a transmission adaptor for a porsche gearbox (not to mention the gearbox is much stronger than that of the nsx).

I should be ready to do a 3 rotor project of some kind within the next year and a half. If my assumptions of the feasibility are correct this is the direction I will go.

-Chris C.

BlackR1

your posts were a bit confusing.

putting a 20B engine in the back of an FD is just silly. The car is technically already mid engine. you'd be spending over 100k on fabrications, and chassis reinforcement alone.

The benefits are....? Even harder to work on? tons of throttle off oversteer?

twint78

black r1 here are my reasons for doing it.the only reason i carre to say why.CUZ I WANT TO.

it should not matter what i want to do with my money.its like ppl questioning jimlab about his money and his car.if someone asks for advice just give it to them.if they want to know about their money they would go to a stock broker or investor.

thanx ccarlisi.i would really like to try it though.the cooling thing is a big problem.but i have a 3 1/2 inch aluminum race radiator made for nascars.i dont think ill have a problem.this radiator is made for 500cid block v8's.i understand that it would be a big hassle,but wasnt that the whole idea with everything when it was first created.it is just something to do.do u have any schematics of just the rear wheel drive configurations,like the engine mount and transmission to rear end hookup?

i think adding that weight to the rearend would help losing it all the time.i would take and move the 20b sideways and shove it in tightly against the wall in front of the rear axle as much as possible.as where the tank sits over it right now.

u think swapping in another rear end would be better?

ur right mazda are better looking but porsches have a name.