steu2011 New Reader
Feb. 12, 2013 10:06 p.m.

Hey all I am probably going to pick up a 1971 240z this weekend.
I am looking at the yellow one.
My goals are to have a fun weekend/auto cross car. I understand that this is going to be a big project, and that it would be much easier to buy one already running. But thats no fun right? My biggest deal is what to do with the engine. I have been looking around at engine swaps, everything from a sr20det to a rb26dett. If I put a Nissan motor in Datsun does that bump me up to X prepared for autocross? Has anyone done this on here and have any input? Should I just get the L24 running? Any help to a noob would be much appreciated. I am on a college budget, but have a job and some money saved up. Any help would be appreciated.

aussiesmg UltimaDork
Feb. 12, 2013 10:09 p.m.

RB25det, RWD, more potential than the RB26dett and easier swap

Swank Force One MegaDork
Feb. 12, 2013 10:13 p.m.

Nissan "is" Datsun so an RB swap would just dump you in Street Prepared at the least. Dunno if the suspension design on the Z car is going to get you real far in that class, so.... who knows? Try it!

ransom SuperDork
Feb. 12, 2013 10:21 p.m.

Wouldn't an engine that different (but same company) be Street Modified?

The small-block V8 of your choice seems to have been an effective route for a couple of local Z cars. But then you really would be in XP.

steu2011 New Reader
Feb. 12, 2013 10:23 p.m.
aussiesmg wrote: RB25det, RWD, more potential than the RB26dett and easier swap

I was considering an rb20det (cheaper than the rb25's or 26's) but I am not sure on what the availability of parts looks like. ON that note, how is finding parts for the rb25? That is one thing about going with an sr20 is parts would be easier and cheaper I bet.

And to Swank Force One: You can get a conversion kit to put s13 Megan Racing Coilovers and Camber kits on a 240z for like $350 dollars so I would probably go that route for starters.

steu2011 New Reader
Feb. 12, 2013 10:23 p.m.

In reply to ransom:

Yeah thats what I was hoping for. SM not XP

Feb. 12, 2013 10:55 p.m.

I'm pretty sure this is what you were reading when I talked to you earlier, but there's good info there on mix-n-matching various Z parts to glean more power.

spnx Reader
Feb. 13, 2013 12:32 a.m.

Not to confuse things, but I know someone who put a 4.5 litre Infiniti engine in one. Goes well

JohnyHachi6 HalfDork
Feb. 13, 2013 1:18 a.m.

If it were me, I'd try to get the stock engine running right first. Then sort out the suspension, steering, chassis, etc. Then, look at engine swaps.

Again, if it were me, I'd look into the 5.6L engines from a Nissan Armada, Titan, or Infiniti QX56. They're pretty cheap if you look around and there's no replacement for displacement when it comes to torque, which is mostly what you want for auto-x. It's also probably not much heavier than any of the other engines mentioned since it's all aluminum vs steel blocks in the inline 6's (IIRC). Don't know about transmission options, but hey, that's what makes it fun, right?

tuna55 UberDork
Feb. 13, 2013 7:09 a.m.

Here ya go - come back when you've been through every engine swap that they talk about over there:

Feb. 13, 2013 7:28 a.m.

In reply to JohnyHachi6:

Oooh... 420hp, 417ft-lb from the VK56VD. 320 and 390 from the VK56DE. Looks like you could get a 5 or 6 speed manual in the late-model Patrols, 5 speed with the R51 Pathfinders, 5 or 6 speed in the L31 Altima, or 6 speed in the L32 Altima. Wonder what that'd cost...

N Sperlo UltimaDork
Feb. 13, 2013 7:32 a.m.

The RB engines will be a perfect fit after you reverse the oil pan which means reversing the sump. Can be tough to get a hold of. RB20s can be gotten for around 1G.

mad_machine MegaDork
Feb. 13, 2013 8:48 a.m.

I have seen (not not heard running) SR20 swaps into Z's, With a turbo, they give great power and pushed back to the firewall, the engine bay just swallows it whole and moves the weight of the car back.

It also gives Z car purists fits

N Sperlo UltimaDork
Feb. 13, 2013 9:22 a.m.

I would assume you have to reverse the pan on the SR as well.

fidelity101 HalfDork
Feb. 13, 2013 9:30 a.m.


then you can fit in the engine bay while you work on it.


turtl631 New Reader
Feb. 13, 2013 10:25 a.m.

Nobody seems to like RWD SR20s very much much around here, but it is a relatively light and cheap option to get you ~350whp pretty reliably with bolt ons like cams and a bigger turbo. Loses the I6 legacy and cool sound though. I'd like to do a VQ series engine into one of these cars someday for a good mix of speed and mass centralization with 6cyl naturally aspirated Nissan goodness.

yamaha SuperDork
Feb. 13, 2013 10:51 a.m.
steu2011 wrote: I was considering an rb20det (cheaper than the rb25's or 26's) but I am not sure on what the availability of parts looks like. ON that note, how is finding parts for the rb25? That is one thing about going with an sr20 is parts would be easier and cheaper I bet.

FWIW, RB20's like to be revved to the moon.....Some parts for sr20's are easily found, others....not so much.

yamaha SuperDork
Feb. 13, 2013 10:53 a.m.

Also, FWIW, I would recommend buying both the blue and yellow 240's.....if one needs certain parts, the other one probably has it.

evildky Dork
Feb. 13, 2013 4:22 p.m.

VG30ET or L28ET are much more buget friendly swaps, can make nearly as much power as their JDM counterparts but at a fraction of the cost and effort, practically no effort if you opt for the L28ET.

Datsun310Guy UberDork
Feb. 13, 2013 5:08 p.m.

for $500 - if it has a title - that is a smoking deal. Have FUN!

pimpm3 Reader
Feb. 13, 2013 5:53 p.m.

Be different swap in a S50 or S52...

J308 Reader
Feb. 13, 2013 6:17 p.m.

Got diesel! If I had room and were closer I'd snipe the E36 M3 outta that right out from under you. Enjoy!!!!

mikeatrpi Reader
Feb. 13, 2013 8:26 p.m.

Is the 81 a turbo? If I remember right in 81 they were automatic-only with the turbo's but you'd be able to use the 4-speed from the 240z or find a more desirable 5-speed pretty easily from a later car.

mw Dork
Feb. 13, 2013 9:04 p.m.

I often get to co drive a 240 powered by a rb26 that's been detuned to only 550hp down from 700 or so. It's a lot of fun. I actually can't stop myself from laughing out loud when I step on the throttle. I don't really know what's done to it and m sure it cost huge money to get to that point, but it's awesome to drive. The best car I've ever driven.

ProDarwin SuperDork
Feb. 13, 2013 9:32 p.m.

If autocross is a concern, SR20 hands down. Its a lot lighter than the other Nissan engines mentioned. Weight means a lot.

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