V8 motor swap
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V8 motor swap
The rotory engines do make power and all it takes some serious money and they a unreliable. The car I have is a 1980 rx7 and the engine no longer works. Plus it has about 150k miles on the old clock. I would like to do the v8 swap because I'm more familiar with them. I was just wondering what all I would have to do in order to do this swap. Maybe take an older trans am motor. Sure its only a 305 at is rated at 200+hp but compared to the monster torque and power this rx7 puts out now. The 305 would probably feel very much more like a sports car. The rx7 has around 100 hp? Thats what I heard anyway. put a shortend rear maybe just a cheaper 10 bolt chevy rear with posi. A good drive shaft and a 5 speed out of a a GM car. What all has to be done to do this swap. Motor mounts trans mounts. How about the rear. how many problems here? Hooking the brakes up correctly? Do they sell any kits that this can be a bolt in project?
Thanks
Brett
Thanks
Brett
#2
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You are evil!! Putting a v8 in an rx-7!! bad, just bad.
If you are going to do it, do it right. get an aluminum block 283 and a 4 spd corvette tranny... sorry, can't remember which year. it was old, though. Using these will keep you as close to the orriginal weight as possible, but you will still have more weight on the front end and you will be throwing off the weight balance.
When you do the exhaust, have the drivers side wrap around to the passenger side and hook up there.
use an electric fan and don't put any more accesories on it than you need.
I knew a guy who did this.. it was a LOT of work. You are better off getting a 13b and dropping it in there. For the money you will end up spending, you can get an awesome 13b setup.
Better yet, if you want a boinger, GET A 280z!!!
If you are going to do it, do it right. get an aluminum block 283 and a 4 spd corvette tranny... sorry, can't remember which year. it was old, though. Using these will keep you as close to the orriginal weight as possible, but you will still have more weight on the front end and you will be throwing off the weight balance.
When you do the exhaust, have the drivers side wrap around to the passenger side and hook up there.
use an electric fan and don't put any more accesories on it than you need.
I knew a guy who did this.. it was a LOT of work. You are better off getting a 13b and dropping it in there. For the money you will end up spending, you can get an awesome 13b setup.
Better yet, if you want a boinger, GET A 280z!!!
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I tried to already have this topic opened but people went way off the subject and almost had to call the U.S. military to help calm down everybody. I was just wondering how much money is invloved. i don't have any 13b motors around here anyway. More weight infront. Naw. Fiberglass fenders bumpers hood etc. That should help.
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spendy spendy spedny
i had my swap all mapped out would cost me around 7k to get it done my way completely,,,,,,,but thats just me i soon gave up on it, and went all rotary.....little cheaper (but still not cheap) but worth the fun level that a little 1.3 liter can cook up. to each his own but im sure youll regret droppin one into an Sa.....if i was gonna chose one i would either chose a third gen with an lt-1 swap,,,,,(only if the TT was gone) or a 84-85 gsl-se....no suspenison conversion necesarry, but u still have to upgrade the springs......and the only fiberglass fenders that are availible are for a widebody kit and dont help much
i had my swap all mapped out would cost me around 7k to get it done my way completely,,,,,,,but thats just me i soon gave up on it, and went all rotary.....little cheaper (but still not cheap) but worth the fun level that a little 1.3 liter can cook up. to each his own but im sure youll regret droppin one into an Sa.....if i was gonna chose one i would either chose a third gen with an lt-1 swap,,,,,(only if the TT was gone) or a 84-85 gsl-se....no suspenison conversion necesarry, but u still have to upgrade the springs......and the only fiberglass fenders that are availible are for a widebody kit and dont help much
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i agree with the other section as well.. we just had a post floating around about this, and ive seen them in the second and third gen forums as well.
as for me? if anything, i would go 2.3t like Eville140 did. they come with a t03 (99% sure) and you can run INSANE amounts of boost on stock internals, and it likes it. i know the merkur xr4ti's boost gauge goes up to 30psi, and the red doenst start till 25. that motor, t5 tranny, 3" downpipe and exhaust, intake, fmic, boost controller and i hear those parts are cheap as hell. i think eville140 said he put $800 in the car, and it ran low 8's in the 1/8 mile. thast just badass.
as for me? if anything, i would go 2.3t like Eville140 did. they come with a t03 (99% sure) and you can run INSANE amounts of boost on stock internals, and it likes it. i know the merkur xr4ti's boost gauge goes up to 30psi, and the red doenst start till 25. that motor, t5 tranny, 3" downpipe and exhaust, intake, fmic, boost controller and i hear those parts are cheap as hell. i think eville140 said he put $800 in the car, and it ran low 8's in the 1/8 mile. thast just badass.
#10
Just send people to http://www.torquecentral.com/forumdi...?s=&forumid=11
It's a whole forum dedicated to the V8 swap. When I have car questions, I come here. When I have motor questions, go there. Both great sets of guys. The guys at V8RX7 are pretty damn anti-rotory, while the guys here are pretty damn anti-pistons. Can't we all just get a long :-)
It's a whole forum dedicated to the V8 swap. When I have car questions, I come here. When I have motor questions, go there. Both great sets of guys. The guys at V8RX7 are pretty damn anti-rotory, while the guys here are pretty damn anti-pistons. Can't we all just get a long :-)
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Originally posted by '85 GSL 302
Just send people to http://www.torquecentral.com/forumdi...?s=&forumid=11
It's a whole forum dedicated to the V8 swap. When I have car questions, I come here. When I have motor questions, go there. Both great sets of guys. The guys at V8RX7 are pretty damn anti-rotory, while the guys here are pretty damn anti-pistons. Can't we all just get a long :-)
Just send people to http://www.torquecentral.com/forumdi...?s=&forumid=11
It's a whole forum dedicated to the V8 swap. When I have car questions, I come here. When I have motor questions, go there. Both great sets of guys. The guys at V8RX7 are pretty damn anti-rotory, while the guys here are pretty damn anti-pistons. Can't we all just get a long :-)
Heck don;t even make another section, save the bandwidth and just make a forum that links to http://www.torquecentral.com/forumdi...?s=&forumid=11
Later
Randy
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Don't go with a 305, waste of time. Go Ford 302. its alot lighter than a 350. A when using a ford 5-speed the mazda driveshaft can actually be inseted into the Stang shaft and welded. Saving some cash as well.
Also, I would not go with the electric fan, I tried one but if you are going to use headers instead of manifolds, the thing won't keep the car cool enough.
Also, I would not go with the electric fan, I tried one but if you are going to use headers instead of manifolds, the thing won't keep the car cool enough.
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Go with what you want man. I'm running a 350 with headers using an electric fan and have no cooling problems. If you want some real answers pm me or email me I'm more than happy to show people "the way".
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Re: V8 motor swap
Originally posted by bmxerbrett
... Sure its only a 305 at is rated at 200+hp but compared to the monster torque and power this rx7 puts out now. The 305 would probably feel very much more like a sports car. The rx7 has around 100 hp? ....
... Sure its only a 305 at is rated at 200+hp but compared to the monster torque and power this rx7 puts out now. The 305 would probably feel very much more like a sports car. The rx7 has around 100 hp? ....
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Re: Re: V8 motor swap
Originally posted by moremazda
...I thought you said these things were unreliable??...
...I thought you said these things were unreliable??...
Originally posted by bmxerbrett
The rotory engines do make power and all it takes some serious money and they a unreliable.
The rotory engines do make power and all it takes some serious money and they a unreliable.
#17
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Originally posted by Winnipeg85GSL
Don't go with a 305, waste of time. Go Ford 302. its alot lighter than a 350. A when using a ford 5-speed the mazda driveshaft can actually be inseted into the Stang shaft and welded. Saving some cash as well.
Also, I would not go with the electric fan, I tried one but if you are going to use headers instead of manifolds, the thing won't keep the car cool enough.
Don't go with a 305, waste of time. Go Ford 302. its alot lighter than a 350. A when using a ford 5-speed the mazda driveshaft can actually be inseted into the Stang shaft and welded. Saving some cash as well.
Also, I would not go with the electric fan, I tried one but if you are going to use headers instead of manifolds, the thing won't keep the car cool enough.
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Brett, filter out the useless crap and listen to the guys that have done the V8 swaps. The other guys only tell you things they think they heard from someone else's friend who's brother dated a girl who's dad wanted to swap a Corvette motor in his 4X4!
Winnipeg85GSL and 85 GSL 302 are not steering you wrong. Neither is rotor vs piston but the Chevy swap might be a little more expensive (couple hundred $) and a small block Chevy is physicaly bigger than a small block Ford.
Is you RX7 a standard or an auto?
By far the easiest swap is a Ford 302/AOD automatic. The auto shifter is cable opperated so you can put it where it's most comfortable. The T5 stick usualy doesn't center exactly where the stock one comes out so you gotta be a little creative. You can buy the motor mounts or make them yourself if you have a welder and the tranny Xmember is even easier to make. Although a Fox body donor car (Mustang, Lincoln LSC or Mark VII) is the preference, any Ford that came with a 5.0 will do. The advantage of the Fox body cars is that they already have the proper double sump oil pan that will clear the front crossmember and steering. (saves you $60 at Summit) You will also use the wiring harness and computer from the donor car especialy if it has EFI.
I don't know how strict your emissions laws are in your neck of the woods but usualy to be legal you need to use a motor that is the same year or newer than the car. Also, the motor has to retain all of its emissions equipment. The catalytic converter is considered a chassis piece therefore the stock RX7 one can be retained if it is functionning. Usualy they are really not adequate because the rotary is notoriously hard on them. The RX7 has two cats in-line with each other. The main cat is an oxidizing type but you can sub in a higher flowing aftermarket TWC (three way cat) that will not affect performance. Because TWCs are better than Oxidizing cats, smog refs will actually give you a pat on the back.
The stock rear end can be used as it is much stronger than most people think, but the stock gearing is a little high. This is why I suggested the AOD Ford tranny. OD has a ratio of 0.67 and will give you an approximate RPM of about 2500 @ 60mph. Lower gears are available but IMHO they are not worth it. A stock 8.8 inch rear end from a Mustang is about 1.5 inches wider than the Mazda rear and can come with gears as low as 2.73:1 if you like. Also, a 7.5 inch axle from a 4 banger Mustang can be swapped in as it is comparable and maybe a little stronger than the Mazda unit which is 7" ring gear BTW. The Ford 7.5 can also be found under Ranger pickups and Bronco IIs. You will need to have your driveshaft modified if you use the stock Mazda rear to accept the proper yoke to mate to the Ford tranny. If you go with all Ford components you may need to shorten the driveshaft depending on what Ford it came from.
If you have more questions, just PM me and we can talk. I can direct you to sources that WILL help you if you are absolutely set on a Chevy motor.
Toughguy
Winnipeg85GSL and 85 GSL 302 are not steering you wrong. Neither is rotor vs piston but the Chevy swap might be a little more expensive (couple hundred $) and a small block Chevy is physicaly bigger than a small block Ford.
Is you RX7 a standard or an auto?
By far the easiest swap is a Ford 302/AOD automatic. The auto shifter is cable opperated so you can put it where it's most comfortable. The T5 stick usualy doesn't center exactly where the stock one comes out so you gotta be a little creative. You can buy the motor mounts or make them yourself if you have a welder and the tranny Xmember is even easier to make. Although a Fox body donor car (Mustang, Lincoln LSC or Mark VII) is the preference, any Ford that came with a 5.0 will do. The advantage of the Fox body cars is that they already have the proper double sump oil pan that will clear the front crossmember and steering. (saves you $60 at Summit) You will also use the wiring harness and computer from the donor car especialy if it has EFI.
I don't know how strict your emissions laws are in your neck of the woods but usualy to be legal you need to use a motor that is the same year or newer than the car. Also, the motor has to retain all of its emissions equipment. The catalytic converter is considered a chassis piece therefore the stock RX7 one can be retained if it is functionning. Usualy they are really not adequate because the rotary is notoriously hard on them. The RX7 has two cats in-line with each other. The main cat is an oxidizing type but you can sub in a higher flowing aftermarket TWC (three way cat) that will not affect performance. Because TWCs are better than Oxidizing cats, smog refs will actually give you a pat on the back.
The stock rear end can be used as it is much stronger than most people think, but the stock gearing is a little high. This is why I suggested the AOD Ford tranny. OD has a ratio of 0.67 and will give you an approximate RPM of about 2500 @ 60mph. Lower gears are available but IMHO they are not worth it. A stock 8.8 inch rear end from a Mustang is about 1.5 inches wider than the Mazda rear and can come with gears as low as 2.73:1 if you like. Also, a 7.5 inch axle from a 4 banger Mustang can be swapped in as it is comparable and maybe a little stronger than the Mazda unit which is 7" ring gear BTW. The Ford 7.5 can also be found under Ranger pickups and Bronco IIs. You will need to have your driveshaft modified if you use the stock Mazda rear to accept the proper yoke to mate to the Ford tranny. If you go with all Ford components you may need to shorten the driveshaft depending on what Ford it came from.
If you have more questions, just PM me and we can talk. I can direct you to sources that WILL help you if you are absolutely set on a Chevy motor.
Toughguy
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Here's a few pics of my Ford 302/T-5 swap. It has a sotck rearend which uses a Ford front half of the driveshaft and the mazda rear yoke.
Now has some different valve covers and is a little cleaner.
Shifter worked out perfectly!
Now has some different valve covers and is a little cleaner.
Shifter worked out perfectly!
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Re: V8 motor swap
Originally posted by bmxerbrett
The rotory engines do make power and all it takes some serious money and they a unreliable. The car I have is a 1980 rx7 and the engine no longer works. Plus it has about 150k miles on the old clock. I would like to do the v8 swap because I'm more familiar with them. I was just wondering what all I would have to do in order to do this swap. Maybe take an older trans am motor. Sure its only a 305 at is rated at 200+hp but compared to the monster torque and power this rx7 puts out now. The 305 would probably feel very much more like a sports car. The rx7 has around 100 hp? Thats what I heard anyway. put a shortend rear maybe just a cheaper 10 bolt chevy rear with posi. A good drive shaft and a 5 speed out of a a GM car. What all has to be done to do this swap. Motor mounts trans mounts. How about the rear. how many problems here? Hooking the brakes up correctly? Do they sell any kits that this can be a bolt in project?
Thanks
Brett
The rotory engines do make power and all it takes some serious money and they a unreliable. The car I have is a 1980 rx7 and the engine no longer works. Plus it has about 150k miles on the old clock. I would like to do the v8 swap because I'm more familiar with them. I was just wondering what all I would have to do in order to do this swap. Maybe take an older trans am motor. Sure its only a 305 at is rated at 200+hp but compared to the monster torque and power this rx7 puts out now. The 305 would probably feel very much more like a sports car. The rx7 has around 100 hp? Thats what I heard anyway. put a shortend rear maybe just a cheaper 10 bolt chevy rear with posi. A good drive shaft and a 5 speed out of a a GM car. What all has to be done to do this swap. Motor mounts trans mounts. How about the rear. how many problems here? Hooking the brakes up correctly? Do they sell any kits that this can be a bolt in project?
Thanks
Brett
However, if you switch to a V8, it's probably adviseable to switch the body as well---- to say, a mid-'80's 300ZX or something. Why rape the soul of the legendary RX7 by ripping its heart out rather than selling it to someone who will give it a good home? Just my $0.02 worth...
#23
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Originally posted by Aviator 902S
Why rape the soul of the legendary RX7 by ripping its heart out rather than selling it to someone who will give it a good home?
Why rape the soul of the legendary RX7 by ripping its heart out rather than selling it to someone who will give it a good home?
It's a freaking car, it doesn't have feelings, it's not going to know the difference. The only person that'll know is the owner, and the people he kills in straight line races in stock RX-7s...
Last edited by Keaponlaffen; 04-25-03 at 01:00 AM.
#25
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Look guys, I'm not gonna get involved in just another V8 swap discussion, cause I'm f**kin' tired of that.
But what I do know is that this topic gets here every so many days, and that's real BS. There's no use in going through the same discussion over and over again.
And IF you need to discus this topic, then at least use facts, not "things you heared from someone you know that knows someone that..."
ROTARIES ARE NOT UNRELIABLE! Anybody who says that is stupid. So I don't give a **** what you put under that bonnet, but don't tell me lies about the reason you did that. If your 12A is not reliable you're just too stupid to keep it going (or the previous owner was). That's all.
Any engine that was maintained wrongly (or not at all) will become unreliable, and unfortunatly too many rotaries have been/are in the hands of people who "think" they know how to deal with them.
There's nothing more to say about that.
So if you still believe you need a V8, go ahead. But I just don't get it why you don't buy a V8 powered car to start with then. Probably even cheaper in the end...
But what I do know is that this topic gets here every so many days, and that's real BS. There's no use in going through the same discussion over and over again.
And IF you need to discus this topic, then at least use facts, not "things you heared from someone you know that knows someone that..."
ROTARIES ARE NOT UNRELIABLE! Anybody who says that is stupid. So I don't give a **** what you put under that bonnet, but don't tell me lies about the reason you did that. If your 12A is not reliable you're just too stupid to keep it going (or the previous owner was). That's all.
Any engine that was maintained wrongly (or not at all) will become unreliable, and unfortunatly too many rotaries have been/are in the hands of people who "think" they know how to deal with them.
There's nothing more to say about that.
So if you still believe you need a V8, go ahead. But I just don't get it why you don't buy a V8 powered car to start with then. Probably even cheaper in the end...