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RB20det transmission question


Ralphyboy

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I can only imagine that it's talked about somewhere but I sure as heck can't find it it using the key words I can think of. I'll preface my question with the cars eventual use so it makes a little more sense too.

 

I deliver Pizza for a living, I see no time in the near future when this won't be the case so I have come up with a plan to make a great pizza car/daily driver/fun car (I've been doing it over 15 years now it's kind of about time lol.) I am going to build my 280zx with a RB20det so I can still have some of the TQ but the small displacement that gets better fuel mileage. I have a gentleman in my sports car club that has a RB20det in his s-14 and is swapping out the short block the beginning of next year. I think for my purposes it would be a great solution because I can make sure I can have a completely fresh engine when I drop it in for four or five years of solid service without having to rebuild it (20 to 30 thousand miles a year if it's a good low year, I've put as many as 62 thousand in 13 months but thats not common.)

 

The question is, is there a transmission stateside (I.E. the KA, Z31, Z32) that will bolt right on? I've read some things about the larger siblings but have not found any info about the 20, maybe I looked in the wrong spot, I don't know. I have to start buying some things for the swap into my car if I buy it like that. It would literally not come with anything but the short block.

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A KA would be fine for what I want it for, I have access to one too (besides the one in my sx lol.)

 

Let me see, that would "only" leave a heck of a lot I have to buy :lol:

 

Head, intake manifold, exhaust manifold, injectors, megasquirt, fuel pump, I'm picking up a sx rear end assembly soon, driveshaft, rear sump oil pan and pick up, motor mounts, fab tranny and diff mount, guages, shoot, piece of cake.

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as for the transmission.

 

you need the bellhousing from the manual RB20, and you might need to modify your driveshaft (will have to most likely due to different engine anyway).

 

the SR20, CA18, KA24, and RB20 all use the FS5W71C. Someone on here has taken one to about 400+ hp with quite good reliability in an RB25 powered car.

 

Getting an RB20 head might be a chore. To be fair, I would buy an RB20DET engine set (IT WILL SAVE YO MONEY IN THE END).

 

It will cost anywhere from 900 to 1200. Don't buy your friend's engine after it's been taken apart. Just get one complete and then take the head off, have the head inspected for warping, change the timing belt and tensioners, change the headgasket, look at the pistons, and get new headstuds and put it back together.

 

this way you get a transmission with it too, and everything you need to get it running.

 

A shortblock means no head. if you're getting a head with your shortblock, it's a long block. You still need coils, ecu, harness, injectors, rail, expensive sensors, intake manifold, etc.etc.etc.

 

save yourself the time and get a complete engine, from one fellow ralphy to another =)

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heck with the money you save, you can inspect the bearings, see if they need replacing, and then just pop a new standard oil and water pump on there too with a new thermostat and new front and rear main seals.

 

YOU WILL save money by getting it complete.

 

if your friend wants to sell you the block for less, buy it for less and then build that up. when you have some down time, take that block, fitted with pistons and rods, and toss evreything from the old block onto that one, and get the some taller/longer dur. cams, and up the boost a bit.

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Well hello Ralph, what a great name you have, very regal if you ask me :lol: .

 

I've gone over all of the scenarios in my head and there are positives to both in my situation. I can get stock 240sx parts all day long, I've already got access to a free transmission if I want it. I would run a megasquirt in that case too and could get ls1 coils dirt cheap. Like you have said, finding the RB20 parts are what worries me a little. The head and intake mani, the bell housing, and flywheel are the ones that make me think a motorset would be the best option. Again, an extra 500 or so would be worth it to me to have everything from the get go in new or like new shape. If it runs 1000 or more, maybe then it's a bad option, and I would not know until I started buying stuff either. The crank has been collared and it has the Tomie oil gallery orifices, when he told me that I told him it may be more than I need, I'll probably just wait for a price from him. He's one of my club members and takes great care of his stuff so it's hard for me to decide which would be better for me in my situation.

 

Thanks for the help with this guys.

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Is the RB20 transmission any different from the L-6 Tranny? Originally the RB20DET was placed in the same chassis that formerly had L20ET's in them and I'm thinking the tranny was the same in those applications.

 

Of course it went into the Z31 Chassis, so that kind of throws a wrench in the 'possible transmissions used' department. Does anybody know if the 200ZR used a standard Z31 Transmission, or an earlier L-Based one?

 

From my recollection of the fuel consumption data at the time, the early RB20 Turbos were consistent with their L-Based Brethern...meaning fuel consumption very near the same. Later RB's, like from the GTS-T Skylines had quite a bit more HP, and I would venture a guess...more fuelish appetities.

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Is the RB20 transmission any different from the L-6 Tranny? Originally the RB20DET was placed in the same chassis that formerly had L20ET's in them and I'm thinking the tranny was the same in those applications.

 

its the 71C. not sure of the case design though. They are a little different from SR/KA to RB/CA.

 

Of course it went into the Z31 Chassis, so that kind of throws a wrench in the 'possible transmissions used' department. Does anybody know if the 200ZR used a standard Z31 Transmission, or an earlier L-Based one?

what is it that you're particularily interested in finding out, perhaps something I can find out using the FAST system.

 

From my recollection of the fuel consumption data at the time, the early RB20 Turbos were consistent with their L-Based Brethern...meaning fuel consumption very near the same. Later RB's, like from the GTS-T Skylines had quite a bit more HP, and I would venture a guess...more fuelish appetities.

the L20ET and the RB20ET both made somewhere around 150hp. Later versions of the RB20 were all DE or DET - making about 10 / 60 hp more, respectively.

 

I would guess that the E and ET versions shared the same transmission as the L20ET's. But the DE's of the later years most likely had the 71C, and not the A or B or whatever the others had.

 

Also, it could be possible that the later RB20 engines that came in the 200zr were equipped with the FS5R90A (BW-T5), but I'd have to check FAST for that.

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Ralph,

 

Don't be swayed by things like the oil gallery orifices. They can be replicated using a mig welder tip and some sandpaper. All you have to do is sand the outside so that it's roughly 6.12mm and carefully drive them into the deck. They won't go anywhere, and you can get them in many sizes. I, personally, have read that it's not a big issues, and that the only reason it's done is dude to the fact that the sump is poorly designed and trapping oil in the head is a bad thing if the sump isn't good at keeping oil where it is supposed to be (near the pickup!)

 

I would stick with a 1.5 or 1.25 mm hole tip. Tomei's are around there anyway. 1mm seems too small to me, so I'm going to run a 1.5.

 

Contact Racer98 or look up his name and a thread will come up where he sells stuff.

 

heres the price of a complete RB20:

 

http://www.tigerjapanese.com/index.php?page=shop.product_details&flypage=shop.flypage&product_id=150&category_id=8&manufacturer_id=0&option=com_virtuemart&Itemid=26

 

atleast this way you can talk to jerryb and see what eneds to be done to drop it in ASAP and get it running to find out whether or not the engine is in good lick. once it is, you can do what you want with it, but I'd just enjoy it =).

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Have we dealt with that company before? Are they a reputable company? That engine even has the AC compressor and, everything, I wish I had the money right now. Alright, I'll just get the whole thing as one piece when I have that extra cash and work from there, thanks, Ralph.

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