doing a 3 rotor conversion!
01-31-02, 11:41 PM
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doing a 3 rotor conversion!
Okay, so I'm going for it. Yup, I'm converting my 88 GTU into a 3-rotor rocket. Now, before I order anything, I need to verify a little info so no suprises pop-up.
Okay, from my understanding, the 20b is 7 inches longer than a 13b. I can use a turbo II drivetrain (clutch, tranny, auto driveshaft, na LSD diff).
Now, I have not ever gotten a clear definate answer as to what EXACT modifications I need to do to the engine bay to fit it all in. I obviously need to get a better radiator, move the radiator/ac condender/oil cooler forward and still have enough room for the intercooler. Now, how exactly do I go about doing this?
Next, I am told that I need to modify the cross-member. What exactly needs to be done to it? I mean, moving the motor mounts is simple, but am I going to have to cut/weld the corssmember itself, or am I just moving things around and lining them up?
Other than how to wire the ECU from the cosmo (or use a nice aftermarket ECU), my main concerns are how to bolt it all in nicely.
Another problem... I want my car to handle like it still does on the corners, but I also like to accelerate wickedly quick, so there is going to be a compromise. Moving the engine forward throws-off the 0 center of gravity (I think it makes it somewhere along the lines of 58/42 if I remember correctly), which means the car will plow into the corners. If I adjust my front shocks to be stiffer, will that counter the understeer, or is more needed? In an extreme case, I could always chuck an 85lb weight in the spare-tire compartment LOL!
Any suggestions as to what I should (could?) do? Thanks for all the info guys!
Okay, from my understanding, the 20b is 7 inches longer than a 13b. I can use a turbo II drivetrain (clutch, tranny, auto driveshaft, na LSD diff).
Now, I have not ever gotten a clear definate answer as to what EXACT modifications I need to do to the engine bay to fit it all in. I obviously need to get a better radiator, move the radiator/ac condender/oil cooler forward and still have enough room for the intercooler. Now, how exactly do I go about doing this?
Next, I am told that I need to modify the cross-member. What exactly needs to be done to it? I mean, moving the motor mounts is simple, but am I going to have to cut/weld the corssmember itself, or am I just moving things around and lining them up?
Other than how to wire the ECU from the cosmo (or use a nice aftermarket ECU), my main concerns are how to bolt it all in nicely.
Another problem... I want my car to handle like it still does on the corners, but I also like to accelerate wickedly quick, so there is going to be a compromise. Moving the engine forward throws-off the 0 center of gravity (I think it makes it somewhere along the lines of 58/42 if I remember correctly), which means the car will plow into the corners. If I adjust my front shocks to be stiffer, will that counter the understeer, or is more needed? In an extreme case, I could always chuck an 85lb weight in the spare-tire compartment LOL!
Any suggestions as to what I should (could?) do? Thanks for all the info guys!
02-01-02, 12:10 AM
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Use the search feature...
LOTS of info on putting 20bs into FC.
First, www.k2rd.com sells motor mounts that will position the 20b in the bay so the tranny bolts up right, and everything fits.
The best way to do the radiator is to cut the current mounts out, and make new ones to mount the radiator completely vertical. You should get an electric fan for it.
You MUST use some form of aftermarket ECU (motec, haltech, wolf) although none of the current ones can run slipt timming on a 20b... so you'll need to figure out a solution for that.
If you keep the stock 20b turbos and dont raise the boost to high, a badass clutch and a TII tranny should hold for awhile... The NA rearend WONT. YOU NEED a TII rear end. You will also need some stiff springs up front to counter the wieght.
Even the TII hood wont clear the 20b... it needs some minor cutting and such.
use the search feature.. alot...
LOTS of info on putting 20bs into FC.
First, www.k2rd.com sells motor mounts that will position the 20b in the bay so the tranny bolts up right, and everything fits.
The best way to do the radiator is to cut the current mounts out, and make new ones to mount the radiator completely vertical. You should get an electric fan for it.
You MUST use some form of aftermarket ECU (motec, haltech, wolf) although none of the current ones can run slipt timming on a 20b... so you'll need to figure out a solution for that.
If you keep the stock 20b turbos and dont raise the boost to high, a badass clutch and a TII tranny should hold for awhile... The NA rearend WONT. YOU NEED a TII rear end. You will also need some stiff springs up front to counter the wieght.
Even the TII hood wont clear the 20b... it needs some minor cutting and such.
use the search feature.. alot...
02-01-02, 08:38 AM
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Originally posted by black_sunshine
Now, before I order anything, I need to verify a little info so no suprises pop-up.
Now, before I order anything, I need to verify a little info so no suprises pop-up.
Originally posted by black_sunshine
I can use a turbo II drivetrain (clutch, tranny, auto driveshaft, na LSD diff).
I can use a turbo II drivetrain (clutch, tranny, auto driveshaft, na LSD diff).
Originally posted by black_sunshine
Next, I am told that I need to modify the cross-member.
Next, I am told that I need to modify the cross-member.
Originally posted by black_sunshine
Moving the engine forward throws-off the 0 center of gravity (I think it makes it somewhere along the lines of 58/42 if I remember correctly), which means the car will plow into the corners
Moving the engine forward throws-off the 0 center of gravity (I think it makes it somewhere along the lines of 58/42 if I remember correctly), which means the car will plow into the corners
Originally posted by Dyre
You MUST use some form of aftermarket ECU (motec, haltech, wolf) although none of the current ones can run slipt timming on a 20b... so you'll need to figure out a solution for that.
You MUST use some form of aftermarket ECU (motec, haltech, wolf) although none of the current ones can run slipt timming on a 20b... so you'll need to figure out a solution for that.
02-03-02, 10:59 PM
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I think that I may have found out where you got the NA auto driveshaft idea. The transmission output splines are not the same size, so there is absolutely no way that it would fit in stock form. Also, the auto driveshaft is about 2" shorter than the manual driveshafts, so once again there is no way that this would work. The unfortunate thing about the information superhighway is that it is also the disinformation superhighway, and sometimes it's difficult to know what is correct.
What kind of crossmember modification were you planning on? I'm only asking because there is no ONE way to swap engines, and I'm interested to see what you were thinking of doing.
What kind of crossmember modification were you planning on? I'm only asking because there is no ONE way to swap engines, and I'm interested to see what you were thinking of doing.
02-04-02, 12:48 PM
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Originally posted by Scott 89t2
before you start I hope you have around $10-20k lying around and a year or 2 of time.
this is no easy task.
before you start I hope you have around $10-20k lying around and a year or 2 of time.
this is no easy task.
02-04-02, 12:58 PM
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Hey evil do you think Maztech could do it for me when I get out of college? I would want to be involved in everything that goes into it but know for a fact I wouldn't have the time.
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02-04-02, 03:21 PM
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to do the swap you need to plan on little surprises, like not being able to get any of the gaskets for the stock turbo, or having to take the turbos off to put the mounts on
mike
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02-04-02, 03:25 PM
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Originally posted by Ryde _Or_Die
Hey evil do you think Maztech could do it for me when I get out of college? I would want to be involved in everything that goes into it but know for a fact I wouldn't have the time.
Hey evil do you think Maztech could do it for me when I get out of college? I would want to be involved in everything that goes into it but know for a fact I wouldn't have the time.
02-04-02, 04:11 PM
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Originally posted by Evil Aviator
You would need to ask them that. I think that it would be a better idea to take it to a shop that has done a successful 20B conversion already, like Pettit. A shop could do it in less time, but they will charge you much more than what it would cost to do it yourself. Also, they are going to want their money up front, as they are not going to let you keep your car in their garage for a year while they wait for you to raise the cash for the next mod, and I doubt that anybody is going to give you a loan for a 20B conversion. IMO it would be better to buy George Samuels' RXX-7 made by PFS.
You would need to ask them that. I think that it would be a better idea to take it to a shop that has done a successful 20B conversion already, like Pettit. A shop could do it in less time, but they will charge you much more than what it would cost to do it yourself. Also, they are going to want their money up front, as they are not going to let you keep your car in their garage for a year while they wait for you to raise the cash for the next mod, and I doubt that anybody is going to give you a loan for a 20B conversion. IMO it would be better to buy George Samuels' RXX-7 made by PFS.
02-04-02, 04:33 PM
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I wouldn't recommend using your NA as the donor car. I used an NA, and ended up putting so many GXL and TII parts in it, that I would have been better off selling my car and buying a TII for the conversion. Besides, you will need something to drive while your 20B car is being built.
Pettit is in the Palm Beach area now. They mostly work on 3Gen RX-7's, but they have a lot of experience with the 20B, and the 2Gen is much easier to convert. A good 20B-REW conversion would probably cost you around $30-40K, but you would need to check with Pettit for more accurate pricing, as it will also depend a lot on what options you want.
http://www.pettitracing.com/
Pettit is in the Palm Beach area now. They mostly work on 3Gen RX-7's, but they have a lot of experience with the 20B, and the 2Gen is much easier to convert. A good 20B-REW conversion would probably cost you around $30-40K, but you would need to check with Pettit for more accurate pricing, as it will also depend a lot on what options you want.
http://www.pettitracing.com/