Howdy Rally Anarchy,

Got a dumb idea in my head to build up a 510 for rally racing. Picking up a solid running 71 this weekend. I have no grand illusions about such a home-grown and ill conceived project, considering my wrenching skills are fair to sketchy, my budget is somewhat-limited, and i'm mostly relying on my own elbow grease and a little help from my friends to make it happen. By my wildly optimistic estimate, I expect to have it done by next summer.

I've been lurking at the edges of rally for some years now, navigating a few events with friends, crewing some, occasionally freezing/drinking my face off as a spectator :lol: I've been wanting to move into the drivers seat for years and i'm not getting any younger, so no time like the present right?

So, why a 510?

Well, why not? I've been steadily improving my street 510 for goin on 7 years, and i know the platform as well as anything else I guess. On the one hand it seems kinda dumb to buy another 510, but i just don't have the heart to gut my white one, even though it would be a way better starting point for this build.

So working with what i got, the new 510 has a fairly weak L18 with SU's, and a z 5 speed. It's a solid shell cept for a few minor things. Oh, and it's SLOOOW. did i mention it's slow? no LSD either.

So yeah, i hope to update this thread and document my misadventures for your amusement. Pictures will follow.

-Brandon

Awesome!

I did the same thing, bought a second XR to do a cheap drift car so I would not smash up my sweet daily XR. One thing led to another..... Don't regret a second of it!

Make it safe, make it reliable, have some fun, then make it fast!

RWD RULES!!!!!!

510 is light and very tossable, very forgiving, and the only reason I wouldn't rally one is that parts and coachwork have gotten very hard to find. If it weren't for that issue that'd be my rallycar for sure.

Go for it! I had a good time racing my 71! While parts may be hard to find, just dont ball it up! No LSD? weld that r160 up! I ran a hybrid motor, peanut head with the 2.2 block. I think they call it the lz hybrid. Great power with 44 mukunis. I was able to keep up with almost all the other 2WD cars out there! Car was very predictable out there on stage, and a blast to drive!

Where at in NE Ohio are you? (And how far away did you have to tow to find a 510? )

---

Pete Remner
Cleveland, Ohio

1984 RX-7 (rallycross thing)
1978
Silence is golden, but duct tape is silver.

I live near Canton.

Picking it up in Cincinnati tomorrow, comes with a nice pile of spares. Also have a spare rusted out donor over in yon weeds with some good parts hanging on it. 3 510's total. Two of em even run.

Did i mention that I hate trailer lights? doh.

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Pete
Where at in NE Ohio are you? (And how far away did you have to tow to find a 510? )

Wouldn't have to ask if people would follow the simple rule of REAL name and real Location....

Nudge nudge Brandon.....

Congrats on the buy! We built a 510 rally car a few hrs years ago..
here is a link to our build on the realm
Rally 510 build

Also we have a pile of L-16 motors laying around an some go fast heads too that we are looking to get rid of kinda cheap! So if you are interested or have any questions let me know!!



Edited 1 time(s). Last edit at 09/27/2010 12:43PM by Cscray94.

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Cscray94
Congrats on the buy! We built a 510 rally car a few hrs years ago..
here is a link to our build on the realm
Rally 510 build

Also we have a pile of L-16 motors laying around an some go fast heads too that we are looking to get rid of kinda cheap! So if you are interested or have any questions let me know!!

I already stalked your photobucket pretty hard to see how you wedged that cage in there. did you cut the roof?

You and Dan Cook are two people i need to talk to I bent Dan's ear at STPR some years ago before i seriously decided to do this crazy thing, as i was already a 510 nerd. I was actually looking for an already-built VW or something to rally, but this 510 popped up for a good price only 3 hours away from me, and i decided it was high time i did something dumb and time consuming.

I'd be interested in some go-fast parts potentially. Still haven't decided on drivetrain, and I need to figure out the rally suspension bits, as all my stuff is lowered with stiff springs and big bars. I'm thinking about staying with the L20b though. I'd be pretty much set on that if i could find a close ratio 280zx gearbox. (i have two boxes, neither are great but both servicable - a dogleg from a 200sx and a zx box with the silly .775 overdrive gear DOH. the 1-2 shift is not great on that box behind an L18.

Are you running a welded rear end? zx brakes up front i assume, but what's on the back?

-Brandon

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dirty_d

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Cscray94
Congrats on the buy! We built a 510 rally car a few hrs years ago..
here is a link to our build on the realm
Rally 510 build

Also we have a pile of L-16 motors laying around an some go fast heads too that we are looking to get rid of kinda cheap! So if you are interested or have any questions let me know!!

I already stalked your photobucket pretty hard to see how you wedged that cage in there. did you cut the roof?

You and Dan Cook are two people i need to talk to I bent Dan's ear at STPR some years ago before i seriously decided to do this crazy thing, as i was already a 510 nerd. I was actually looking for an already-built VW or something to rally, but this 510 popped up for a good price only 3 hours away from me, and i decided it was high time i did something dumb and time consuming.

I'd be interested in some go-fast parts potentially. Still haven't decided on drivetrain, and I need to figure out the rally suspension bits, as all my stuff is lowered with stiff springs and big bars. I'm thinking about staying with the L20b though. I'd be pretty much set on that if i could find a close ratio 280zx gearbox. (i have two boxes, neither are great but both servicable - a dogleg from a 200sx and a zx box with the silly .775 overdrive gear DOH. the 1-2 shift is not great on that box behind an L18.

Are you running a welded rear end? zx brakes up front i assume, but what's on the back?

-Brandon

Brandon,
making power out with anything with the L series non crossflow heads is pretty grim task.
Ports and valve sizes aren't too good, and these days finding decent induction---manifolds, isn't too promising...

While i have a big soft spot for the CAR, I never was very overjoyed when friends in years past wanted me to build them L series motors..

HOWEVER! Since L-series, NAPS-Z and the KA24 blocks share a lot of stuff (like main bearings and some timing chain stuff) between thos motors there's a ton of possibilities for mix-n-match.

L20 block and crank are good, but look at the trend that Nissan themselves did when they went to use the basic same L20B stuff in cars rather than the old pick up: first thing they did was make the rods longer and the piston compression height shorter.
L20 stock comp hgt is around 38.5mm and the rod is 146mm center to center.
Bore is 85, stroke is 86.
Now 86 x 86 is a very common combo in a number if high performance engines ( Toyota's excellent 3GSE used in the All-Trac, GMs killer "XE" 16v Cossie headed Kadett and Astra GSI, Ford's (never seen in USA) RS2000 Group A F2 motor and some earlier Peugeot/Renault Group A F2 motors) so unless you just happen to have piles of later NAPS-z blocks not a lot of reason to go crazy searching---or spending time and money...

But the key to happiness is, if you read a lot around here, keeping the LABOR content of what you farm out minimal, and cylinder head work is EXPENSIVE, but in normal aspirated, there's not a lot you can do if you have a basically poor design like Nissan's copy of some early 60s Mercedes---which is what it is.

Just getting the came to "wipe' the finger follower correctly is very critical, and very annoying, specially these days when most places haven't done one in oh.....25 years.

SO!
Didya know that the bore spacing and head bolt spacing is the same on the KA24DE?

In other words this:




With these ports


Will BOLT ON to the napz or L-series block, trather than this at best morphodite ex-Nazi schrot:


Even if you don't beautify the KA24DE ports till you jizz all over them they are lightyears ahead stock compared to insanely expensive, big valve L-series heads in terms of port area, and valve area.

What I'm suggesting is you would be ahead in the dollar spent/laugh return curves by BUYING a PART and figuring out the front cover and chain issues if any than spending TONS on labor trying to make a L20-B head make power.

And that's just flow.
The second and as important half of the equation is thermal and the nice pent-roof chamber with center sparkie plugskie is going to be TONS more detonation resistant than the old open chamber with crappy quench pads:


here's what some smart cookies are doing to give them some compression AND detonation resistance:




Looks like a lot of very expensive work to me, when there are much better alternatives just laying around in the bone-yards rotting.

Oh the intake valve size stock is 36.6mm for KA24DE, 42mm for the L20B so 2 x 36.6 valves is 52% more valve area than on 42mm, that means even a way milder cam will let the motor inhale way more fresh air than even rad high lift, long duration cam will allow into the L20B

Whaddya sink?

As for gearbox, why search for something hyper rare?
Get a bellhousing loose somehow and use something EASIER.
The L28 turbo used a T5 which means loose bellhousing and L-series block....

Curt,

Very nice looking 510. If my cage looked like that I would feel much more comfortable doing the things I've done in my car 510.

Brandon,

If you haven't found them already, links to my rally beater 510 series can be found by going to eyesoreracing.com and scrolling about halfway down the page.

There honestly isn't that much valuable info in that series any more, but there are still some useful details, like spring rates, that will help you. You'll also notice that I did all my racing with an open diff. I tried welded briefly, but it was terrible to drive. I've known fast 510 guys who disagree, but in my experience, if you like any handling finesse at all, don't weld. The welded diff was plowing understeer or snap oversteer, with nothing in between. (My bad experience with the welded diff was on narrow 2nd and 3rd gear stuff, where the 510 can lay waste to WRXs. On wider, faster roads, the answer might be different)

If I were to start over and build another 510, this is what I'd do:

Still run an SR20.
Naturally-aspirated rear-drive SR20s are cheaper than rebuilding an L-series. They make perfectly adequate power in completely stock form, and they're completely bulletproof. My car is an ugly, nasty mess, but it fires up on the first crank every time, never overheats, and I'm never wishing for more power.

Use an S13 front subframe.
My 510 can be fast, but its an incredible amount of work to drive. I'm constantly sawing at the wheel to stay on the road, the steering is heavy and not as quick as I'd like. There is about a quarter turn of slop in the wheel, and I have to pump the brakes two or three times before they'll work. All of this is built into the design.

510 steering is a series of pulleys and levers all controlled by a box full of worm gears and monkey nuts. Every 510 box on the planet is worn the hell out, and there's not a damn thing you can do about it. The car REALLY needs a steering rack.

My next 510, if I had the time and energy to build one, would use an S13 240SX front subframe, steering rack and all. This can be made to bolt to a 510 with relatively minor fabrication. This gets you a steering rack, vastly superior brakes (and brake geometry that is ineterchangable with a lot of modernish Nissans), and modern bolt-on struts. Bolt-on struts let you run a much beefier strut body that will not only be stronger, but run much cooler.

I would also swap to S14 spindles and hubs (you have to use S14 ball joints to do this) since they are significantly beefier than S13. S14 control arms are longer, though, which is probably not advantageous.

Alternately, you could get an S14 subframe and swap in S13 steering arms and control arms. Or you could just be a little wider.

I should point out that an S13 is still about 6 inches wider than a 510. This car will require fender flares.

Consider, for a second, how little work the porposed swap would be. You're changing a lot of parts, but they only attach to the car in three places. Subframe bolts to frame rails (must modify the subframe slightly to line up with 510 rails), T/C rods attach to front of car (probably have to fab new rods here, which is dead simple), and strut tops go up in the strut towers. Strut tower spacing on an S13 is wider than a 510, so there will be some fab here, but possibly nothing more than clever top mounts.

Best to think about this idea before you build the cage and reinforce the strut towers.


Use a 280ZX rear subframe.

There were a couple years of early '80s 280ZX that used semi-trailing arms like the 510. They were so similar to the 510, in fact, that I think the subframe mounting bolt spacing was the same. Nobody ever does this swap, because the 280ZX is 6 inches wider than the 510, but as you recall, I just made the front 6 inches wider, so this is a perfect fit.

This swap gains you several things:
1: rear disc brakes
2: a thinner subframe cross section designed to allow the exhaust to pass under the subframe instead of through it. This saves a lot of headaches and makes it much easier to run a big enough exhaust for an SR.
3: rear coil-overs. 510s put the rear spring perch in the trailing arm, while the 280ZX had a coil-over. Some reinforcement to the 510's upper shock mount is probably in order here.

I am not certain of this, but I THINK this subframe will bolt in.

Some early 80s 200SXs also used semi-trailing arms and may be a better choice. Its worth spending some serious junkyard time measuring and taking pictures. Keep in mind that on both the 280ZX and the 200SX, there were identical looking cars with different suspensions under them, so just because you've looked under one, don't assume you know what's under another. Variations go with both model year and engine.


Swapping these major subsystems instead of monkeying around with individual parts moves you 20 years forward in parts availability and gives you componends designed for much heavier cars, so they'll be crazy-strong.

Since the SR20 has a power steering pump and the S13 rack is designed to be power assisted, I'd also take advantage of that fact and run power steering with a quickener. You gotta move the wheel a lot in a 510, and a quickener would be awesome.

-Dave

Dave Coleman, delirious and on hard core barbiturates scribbled:

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and modern bolt-on struts. Bolt-on struts let you run a much beefier strut body that will not only be stronger, but run much cooler.

Bolt on struts lets you bolt on stuts.

And is worthwhile because then you can---if you had the foresight to buy and take a spare----swap in a spare in the typical service time you have.

However, he is babbling nonsense when he says it "let's you run a beefier strut body".

Good suspension, purpose built for hard rally use such as JVAB "Soooper Bitchin Suspenders" use the exact same 4130 DOM tubing for all their strut tubes (or bodies)
The length is the only significant difference.
In point of fact---before this becomes a silly "discussion"--"Old school" weld in units are a bit stronger because of the inner "slide in/weld in bottom extension part, PN 60600014 which means there is an additional wall thickness at the bottom.

Serviceability in the time allowed means that "bolt on" via ears or bayonet is much preferred, but of course a swoot frood like JVAB has and can make excellent durable suspension for the 510 either way.

As for using a SR20DE, they are an excellent engine and look at this:

Just $800. engine and gearbox.
$800 doesn't buy a lot of machine work.

THE problem with the SR20DE is that it is SOOOOOoooooooooooooooooOOOOOO nice that it's just asking for MORE COMPRESSION and MORE CAM
to make it seriously kick-ass-----and that generates need for somewhat closer ratios or you get the dreaded BWWWAAAAAAAAaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa----duh! uh uh uh---uh--uuuuuuuhhhhhhhhhhaaaaaaaaaaaaAAAAAAAAAAAAAAAAAAAAHHHH--duh!

on gearchanges, and that sucks huge donkey wieners.

And although the details on getting a QUICK rack may differ, the absolute need is glaring...although there are of course simple ways.

MMmmmm, barbituates....

Beefier struts because the 510 tube limits the insert diameter you can *easily* do. I suppose you could just weld a more bigger tube to the 510...

Anyway, if there are easier ways to do a steering rack, what are they?

-Dave

I personally thought that the stock oem ka24de and five speed that I put in a 510 a few years back had way more power than I needed for that little car. Enough that I figured I could get myself into serious trouble with it if I were to race it! So cool that the thing just slipped into place with little to no modifications! With talk about the other possible motors my thought is how much power do you need?

Ask Mark Donahue...

Serioulsy, though, my SR only makes about 140 at the wheels. But it does so with less weight than your KA, and with a powerband that's a bit more flexible.

If I was building a rally car frmo a 510 that already had a KA, I doubt I would bother replacing it with an SR. KA would be enough, but if we're sticking something in to replace an L, the SR is clearly the way to go.

-Dave