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Hi guys, i'm going to be attempting in the near future a swap of my l28e in my 280zx to an rb20det and wanted to ask in here a few questions that i have.

firstly, how difficult is the conversion? what sort of things will i need for the conversion? is there anything i need to take into account?

secondly, i was thinking of selling the rb20 turbo and putting a bigger turbo in, such as an rb25 turbo. Is this possible? also, how much would i be able to a) sell my rb20 turbo for, and B) buy an rb25 turbo for (and where from)?

lastly, does anyone know where i can sell my l28e once i've done the swap and approx how much i will get for it?

thanks for you help guys

Matt

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I'm not too sure on the selling prices, but the RB25 turbo onto the RB20 engine is definitely a good idea.

I also think the RB20 swap is a good idea too - although I don't know how hard it is. People have done it before, so someone should be able to help you. You'll get much better economy and the benefit of a tweakable engine with a huge aftermarket parts catalogue. The RB20DET also has more power than the old L28E. The RB20DET has 158kw/265Nm and the L28E has roughly 100kw and 200Nm from memory.

Finally when you're done, you must take me for a spin in it.

It’s a fairly expensive exercise to put an RB motor into a Zed, therefore you should be putting RB25DET or even RB30t, as those extra cubes will make the car much better to drive.

To put an rb26dett into a Zed costs around 10k (excluding motor).

Do it once … do it right.

Talk to SPEED TECHNOLOGY as they have done RB conversions into Zeds.

03 9873 5400

Thanks for the replies guys

I didn't think it was going to be that complicated, rb25 is out of my budget so if i was going to do anything it'd have to be something a bit cheaper. I'd like to do it the best way that i can first time around but a lot of money just isn't available right now and i'd still like to do something. From what i can gather the performance is up'd by about 150% when going from l28 to rb20, and i heard that the rb20 isn't too hard to fit in... (?)

Anyone else able to offer some advice?

thanks

Matt

The motor won’t be much compare to the rest of the project:

- New exhaust

- New plumbing for the cooler

- New engine mounts/ or modified engine mounts

- New clutch

- New G/box

- Will need new G/box cross member as L series

motors lean to one side, yet RB motors to the other

- Brakes upgrade for engineers report

- Wiring

- Intercooler

- New ECU (stock ecu may do to start with)

- New fuel pump, fuel reg.

- Sump might need mods to clear cross member

- Labor ( unless you plan to do most of it your self )

- Engineers report

etc. etc.

I think you’ll end up spending at least 10k on the conversion,…… and for that money you might as well sell your car and buy a R32 GTS, which would be a better car to play with.

These are just the most obvious things that will be required. I know a bit about it as I am also putting an RB motor into my Zed next year.

Also a friend has fitted an RB26 into his Zed.

Hey guys

As for the new bits i'll need, i've taken a few of those things into account already, i've got a 2 1/2 " exhaust all the way through, i've priced an engine ($900 with electricals) and g/box ($350), not sure what those other parts will cost.

How hard is it to modify the engine mounts? gearbox mounts easy to find and put in?

as for getting a skyline, well, a) no cash, B) my car is my child that no skyline could replace (you should know, you're a fellow z driver)

Mattrix

Matt, you know you want a Skyline. Sell the Z and step up to a real sports car :(

Those prices look good btw. It does look like it'll be a very expensive excersize if you take the prices of the parts mentioned above into account, though.

BTW RPMZ, that is a sweet Z you've got there and a nicely done site (although I can only get it to work in IE). How do you find the 7.3:1 compression ratio? Is your car a lag machine?

hehe .......... yes Zeds are addictive.........

but the project will end up costing a lot more than what you think....... so you should be aware of that.

If you don't have much cash I would start the conversion as these thing always end much much more than anticipated, and I'm sure you don't want your car off the road for months.

:(

P.S...... I still think 2L isn't much for a bigger 280zx.....

MIC33R .......... lag ............... since I've put the GT30 I forgot what lag is (awesome turbo) boost from 2500 rpm

7.3:1 comp ratio is a bit too low, however with a 1100 kg car is not much of an issue and the car is good off boost as well, and at 4000rpm the car already makes 200rwkw (racepace dyno)

12.2 @ 117mph

12.1@116mph

P.S. I have to agree with nemz last post ...

Well I won't argue with those times :( It sounds like your car is an absolute beast (the vids were nice). Let us all know how the RB transplant goes. BTW which RB is going in?).

Mattrix, maybe you could look into the L28ET idea if you don't sell it and buy a Skyline :) From the looks of RPMZ car, they're certainly no slouch. Can you can just swap the heads and pistons to upgrade the L28E?

if you have the money to do up a zed, and the passion and the time, then go for it, you will have a nice car, but if not ure just gonna end up with something that isnt what u want, gonna have probs gonna be off the road, better to just keep what u have for a while and save for an r32

p.s will the rb26 add much weight"? if it dont meh thats gonna be one hella fast car

yeah, l28et would slot in nicely but i'm not sure what my chances are of finding one, and even then i dunno if i'd get it for a decent price.

Or alternatively, how would i go sticking a turbo on the l28e? difficult? expensive? the engine only has 169,000km on it, so it's probably got plenty more years left on it (i hope)

and guys, please, i'm not buying a skyline :D i love my zed, there's not many on the road and i like it that way.

I just thought I'd add that if you can source a sump from a Z31 200ZR (like a 300zx, but with an rb20det from the factory), that should make the conversion a little less painful.

I'd like to pull the RB30E and five speed from my R31 and stick it in a 240z, don't think that will happen though...

cheers,

floody

  • 2 weeks later...

Ok, latest update for those that are interested. Found out that a guy at my church knows how to drop an rb20det into my car and do all the necessary work involved. Says that it'll be about $4000 all up but he's still looking around to see if we can do it for cheaper. It's looking as though i will get the r31 rb20det and put an rb25 turbo onto it, get a skyline radiator, new gearbox and all electricals, new fuel pump, new engine mounts and gearbox mounts, and not sure what else my mate has in mind, but it sure is looking exciting. will have to keep everyone updated as it happens, and take photos as well.

Matt

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