Motor Swap

[lexxxx]

I wanted to know is there any diference in RWD than in FWD. Does it do any thing or is it just front tires going than rear one's. Thanks

[godenm]

what do you mean is there a differance

[lexxxx]

is there a power or Torque difrence or anything

[4dr92cavi4cyl]

There is a weight difference, due to RWD having a rear differential and drive shaft, I would say RWD also has a little more loss of power through the drivetrain. FWD are lighter b/c there are not as many moving parts, and more power gets to the ground. That's why most 4-cylinders are FWD, and most V6 & V8 are RWD.

The biggest difference is how they handle!

The front tires on a FWD car have to take care of the power, 80-90% of the braking, AND turning, of course the back wheels just roll, and help 10-20% braking, and the park brake, so they tend to understeer, or keep going straight through a fast corner.

On a RWD car the turning and power are on independent tires, so the fronts are just going to handle all the turning and braking, the rears give the power to the ground, so RWD tends to oversteer, or slide sideways through a fast corner.

Another major difference is the weight on the drive wheels, with a FWD having the motor on top of the drive wheels it's easier to put more power to the wheels without burning out, but not on a RWD 'cause there is less weight on the rear tires.

I like that Sig. LOL! Ain't that the truth!

[noshun]

Originally Posted by 4dr92cavi4cyl

Another major difference is the weight on the drive wheels, with a FWD having the motor on top of the drive wheels it's easier to put more power to the wheels without burning out, but not on a RWD 'cause there is less weight on the rear tires.

This is untrue. A RWD car will pull away better off of the line regardless of where the engine is sited. This is all due to weight transferrence. When you accelerate the front end of you car will lift and the rear will lower. This is known as squat or pulling out of the water. This is weight tranferrence. Upon pulling away the majority of a cars weight is shifted to the rear (obviously except in reverse). Under this situation the front end will go 'light' meaning less traction at the front end so you are more likely to wheelspin. Adversley with RWD the weight is transferred to the drive end of the vehicle giving the car much better traction and therefore more power can be fed to a car. So 2 cars with identical power to weight ratio (whp) and with drivers of the same competence the RWD car will beat the FWD one. This is shown in Drag racing. Ever wondered why FWD drag cars have wheelie bars? And ever noticed how there are very tightly sprung and very close to the ground? The reason is due to weight transfer, the bars stop too much weight being 'robbed' from the front wheels by proving a reactive force in the opposite direction.
The reason cars were made as FWD goes back to 1959 and the unveiling of the original mini. Sir Alec Issigonis (English despite the name) created this car as thew first FWD car. The mini also featured the first transversely mounted engine (copied by Lamborghini engineers for use in the rear of the Miura thus starting the MR layout) vs the traditional longitudinal with RWD layout. The reason for this was simply packaging. This allowed a vehicle with around only 10 feet in length to be as spacious inside as car up to 5 feet longer (I'm not saying it was spacious). This is mainly due to the position in which the motor was mounted. As you know an engine (in a car) is a lot longer than it is wide. Therefore by turning the engine through 90 degrees counterclockwise (from above) the hood only needed to be half the length than for a longitudal engine. This was also helped by the single port face head of the A-series Austin-Morris engine. The engine was still the same size as those going into the larger Morris vehicles of the time. Such as the Minor. Also as there was no need to power the rear wheels the bed pan did not need to make room for the prop and rear diff that encroached on the interior space. Another reason than that of packaging nowadays is production. The fact that the complete driveline is located at the front of the car, means that the motor transmission, front struts hubs etc can all be assembled as a unit while the body is being readied for this to be installed and as a result is just bolted inplace in about 1/2 the time it takes to place the motor in and then attach a prop for the rear diff. Therefore lowering production costs. A great example of this is the Nissan Micra (the new one). In the factory at Longbridge in England these cars go from sheet metal and shipped-in items to a road ready car in just 6 hours!! Although this car is VERY ugly. A great example of the RWD layout encroaching on cabin space is the New BMW 1-series. This vehicle is only currently on sale in Europe and starting at about $30,000 for the 116i (1.6 115 brake horse power [if you ever wanted to know what the brake in BHP stands for, it means power at the brake, this means that amount of power to stop the engine dead at it's output, so essentially, power at the flywheel]) This car is a BMW and BMW's slogan, "The Ultimate Driving Machine" therefore they were no-way going to produce it as a FWD so RWD it is. The only problem with this is, as it is the size of a Ford Focus on the outside and RWD, the interior is a little cramped. It only really will seat four as the rear occupant room is greatly decreased by the prop and diff being mounted under and in this space. Also the transmission is between the front passengers and as a result the pedals are kind of off to one side and the front footwells quite tight! Ultimately RWD is better but FWD more 'practical' (who wants to be practical). FWD cars do experience understeer due to the front wheels being driven and the wheels just wanting to go straight ahead when fed power, but this is not limited to FWD'ers. A lot of Grand Tourers, such as the Aston Martin DB7 are front engine RWD but can suffer understeer this is all down to the huse mass of engine (V12) in the front trying to push the nose wide. If however you do experience understeer, on the 'Street' just ease off of the throttle and the front wheels will regain traction. Under 'race' circumstances a completely different technique is used. This requires a fair amount of skill. I use it fairly regularly even on the street and is a means of not losing too much speed/time. The technique is called 'left-foot-braking' and while most car people have heard of this they have no clue why it's done. It's all about weight tranfer when it comes to understeer. What you do is while still regulating the throttle with your right foot, you 'dab' the brake with your left. Obviously the amount of brake you provide depends on how badly you are understeering and weight is shifted to the front wheels helping them to regain traction. This technique can also be used to evoke oversteer. This is done by hitting the brake harder than needed and tranferring more weight to the front as needed thus leaving less at the back and therefore less traction which can be broken and then you will expericence oversteer. Yes, even in FWD. This isn't however the only way to evoke oversteer in a FWD. The other way is lift-off oversteer. This is done by getting to the limit of your tires adhesion on a corner and then lifting from the throttle and at the same time, providing a sharp turn-in. This should bring the back end out. The easiest way to do it is with a scandinavian flick which entails, steering left before right into a right handed corner and this unsettles the cars weight distribution as you enter a bend with the weight on the inside wheels due to turning the wheels the opposite way first and then back before the weight can shift back completely, this coupled with lifting off the throttle can get the back end to come around very quickly meaning that you need to correct it with steering and throttle quickly to avoid a spin. Obviously there is also the e-brake but you'll flat-spot your tires. Not Good!!!

[4dr92cavi4cyl]

I was thinking about that yesterday on the way home, I thought, wait a minute, as soon as you apply power most of the weight goes to the rear, regardless.

Know all about the e-brake technique, flat spots are dangerous! The e-brake should only be used for what is was designed for, EMERGENCY, or to park.

[noshun]

Originally Posted by 4dr92cavi4cyl

.

Know all about the e-brake technique, flat spots are dangerous! The e-brake should only be used for what is was designed for, EMERGENCY, or to park.

unless you're on a low traction surface, then it's just great fun!!!!

[4dr92cavi4cyl]

TRUE! I love the snow! My dad and I went out for some "donuts" a few years ago, there was about two inches of the fun stuff, he had his Blazer (w/350 small block!) and I had my Cav. We found a small parking lot that was more like a small oval track. I had a blast! FWD is so easy to enjoy in the snow, my dad couldn't get the blazer sideways but my Cav was everywhere! I miss those days...

[noshun]

Originally Posted by 4dr92cavi4cyl

TRUE! I love the snow! My dad and I went out for some "donuts" a few years ago, there was about two inches of the fun stuff, he had his Blazer (w/350 small block!) and I had my Cav. We found a small parking lot that was more like a small oval track. I had a blast! FWD is so easy to enjoy in the snow, my dad couldn't get the blazer sideways but my Cav was everywhere! I miss those days...

Teh best thing to do is when you have pulled the e-brake and turned in and the car has started to slide. Release the e-brake. and as you always want to dip the clutch when you pull the e-brake wether FWD or RWD (RWD will stall otherwise as you are locking the wheels the engine is trying to drive) Then you want to lift the clutch in say 2nd gear and feed in some opposite lock ond then you cankeep the car sliding and after some time you will be able to do perfect 180 degree turns around things like rally drivers on very tight hairpins.

['94CavyRs3.1]

Or squeeze a small block V8 under there with some inner wheel well work run it with say a camaro rear axle, add a blower and then go vette/viper hunting that'll give the old guys in them something to think about



i had a similar idea..but to take a northstar motor out of the Caddys and put it in my cavy and have some fun...


and no 3.1 arent a slow motor for who ever said that...i have had nothing but good luck with mine and its quite quick...running at about higher 15s with nothing done to it... pretty sad when u can take 2002 mustangs.

[noshun]

Originally Posted by '94CavyRs3.1

i had a similar idea..but to take a northstar motor out of the Caddys and put it in my cavy and have some fun...

Fair amount of work there. It was intended originally as a joke as the guy didn't want to do too much for the motor swap but on top of the work needed to install a longitudinal V8 you have the whole injection and ignition system to worry about. A carb'd motor with distributor would be a lot easier and although it may not be as efficient it can be tuned to the same horsey numbers! Also would have to cut the bulkhead about a lot and make room for the trans, meaning cutting the front central part of the floorpan about and then possibly the floorpan all the way through the centre of the car to make room for the prop and you'd probably have to fabricate an entire rear suspension that would obvioulsy have to be 'true' with the car. It would be some great fun no doubt but would cost some green!!!! I'd like to see the car that was supposedly done it would be a great thing to see. IU would also want to stiffen up the entire body, probably something like an 11-pt welded roll-cage and some bracing (more than just strut braces) between the strut/shock towers. A lot of torque would twist a unibody up nicely!!!!

Getting hold of 2 2.8 would be fun. Use all of the front running gear from another z24 and then put the second motor in the back powering the rear wheels. That would make it some kind of 5.6 double-Vee 12. You wouldn't even need to tune the motors. Would be 4Wd (not to be confused with AWD, no link between the tow so no torque balance/tranfer via a centre diff) so traction would be great. There's defintely a lot of room back there for it all!! Hmmm sound like a fun winter project for next year. I'm gonna go balance my check book!

[lexxxx]

THanks for the input on that frw and rwd stuff. and one day me and my buddy where in a parking lot one day when it was raining and i did a full 360 in my 1990 cavi i dahm near shit my pants after the fact but it was cool. in fact now i can do a 180 with out even thinking about it

[93_R/T_TT_Stealth]

LOL @ the sig. "NOS is like a hot girl with aids you wanna hit it but are affraid of the consequences" - thats funny stuff - it is unless ya bore an sleeve/new pist./ring ect.... on it to forcome the stress thats gonna be put on it - lol very good quote though - props dude
you guys did alot of postin in this thread i posted in the begin. but then couldnt log on for some reason - i missed alot

[lexxxx]

ya i was thinkin about rebuilding my 2.2l sometime next summer and when i do im going to get it set up to beable to handle nitro and im going to get complete rebuild from oilpan bolts to valve cover i wan see if there is any way without a turbo or nos or any add ons that give major gains just the engine and bor and stroke im going to try to get 300 hp out of it if i can or as close as posible

[noshun]

Originally Posted by lexxxx

ya i was thinkin about rebuilding my 2.2l sometime next summer and when i do im going to get it set up to beable to handle nitro and im going to get complete rebuild from oilpan bolts to valve cover i wan see if there is any way without a turbo or nos or any add ons that give major gains just the engine and bor and stroke im going to try to get 300 hp out of it if i can or as close as posible

You'll need to get the reciprocating mass down as much as possible, have the crank balanced, high-compression pistons, and roads, Use ARP fasteners everywhere. You'll need about a 270-280 approx cam and see if you can get some rollertip lifters, port the head maybe polished too, new intake plenum and manifold, air feed about 6' from the ground, where the air is at it's coldest and therefore densest point. You'll need high flow injectors and fuel rail an uprated fuel pump, a good fuel pressure ragulator, headers, and a dump pipe (very short exhaust with no boxes that exits at one side just behind a front wheel and bends will have to be as smooth as possible, as big of an air filter as you can get to increase the surface area attached to an intake that it as straight as possible, lightened flywheel and uprated clutch or torque converter, you will need some engine management changes in this case the stock system WILL lean out. You won't get much more torque as you will has no exhaust back pressure but you will make quite a few horses. Wont get that close to 300 though but let us know how you get on. Will be very interesting to find out what it can do!!!! And for how much!!