Hello all roadster guys! I'm a S30 Z car guy coming over.

[olderthanme]

Hi guys!
I started my obsession with an early 1974 260Z. It had some light mods done to it and is now being parted out. I bought my 260Z in 2003 and have spent lots of $$,$$$ on it and it still looks like junk. LOL

I am a 20 year old Mechanical Engineering student but have already graduated from a welding school with a degree in Welding and Joining Technology and individual certificates in MIG (all positions), TIG(mild steel, aluminum, and some stainless), and SMAW (all positions).
I normally post on www.HybridZ.org and have nearly 3,000 posts there but nobody knows about roadsters on HybridZ.

On my 260Z I had done:
Engine rebuilt with new bearings, gaskets, and powdercoated the engine block and valve cover.
L24 flat-top pistons to increase compression ratio. (9.2:1 SCR)
Early 240Z SU carbs with individual pep-boys 6" air cleaners(worked great!)
Mystery header and 2.5" mandrel bent exhaust to a turbo muffler.
Stock driveline otherwise

powdercoated prismatic black (black with color shifting metalflake) at www.thepowdercoater.com by Mike who is a fellow Z car guy...




I modified the struts and converted them to coilovers and TIG welded the new perches onto the strut tubes.
Tokico illumina adjustable strut inserts

poly bushings
new U-joints
15X8 diamond racing wheels (CASCAR legal...) with 4" backspace
Toyota solid rotor 4 piston calipers
drilled/slotted rotors(DOH! should have gotten regular rotors but oh well!)
high performance rear shoes.
Mitsubishi Eclipse seats
3Lb aluminum dash that I made.(40Lb weight savings)
Wiring harness made from scratch...
SPEC 11Lb flywheel and stage 2+ clutch (rated to 265hp)
rebuilt gas tank
removed heater/fan
all new/rebuilt engine acessories
New pins for the shift rods in the transmission in Fall of 2004. I was shifting hard from 2nd to 3rd and when I dropped the clutch at WOT I discovered that it didn't go into gear and the shift lever fell out of the gear selectors. Pegged out the 8k RPM tach.

Now I'm planning my roadster.
I'm trading the 260Z body for a Japco full body kit.
Identical to this one:

I'm wondering if my 15X8 wheels with 4" of backspacing will work with these fenders and clar the suspension and frame.
I read somewhere that Z car brakes will fit on a roadster. I have stock 260Z brakes and my toyota 4 piston calipers that bolt on to the stock z strut. It would be great if they will swap over. I also have a series 1 240Z brake booster that I bought new($400) so hopefully I can make it work.

Motor choice is up in the air still.

I've looked at a FWD Infinity G20 SR20DE. There is an adapter to mount it to any L series datsun tranny.

Looked at the CA18DET with 5 speed (nice and light weight, turbo!, revs high, relatively cheap, easy to mount, great MPG)

Also considering my project motor that I'm building.. VH45DE. Don't know how well it will fit though. Probably a tad on the heavy side for good handling on a road course.

Also maybe a turbo L20B?

I'm leaning toward the CA18DET since it will get good mileage for the highway(30mpg ) and be capable of ~250hp+ on a stock longblock.

I love the L series engines(I have 3 L6 blocks, 2 of them supporting a workbench) a LOT but I think it is time to move on to newer DOHC crossflow engine technology.

I enjoy this forum a lot! Hope to learn more and maybe even contribute some!

Dan

[Chris66]

OTM, is that engine stand hanging in the ceeling?????

[Chris66]

Oh, i forgot to say welcome, i'm new here my self and i know about you from HZ

[datsunrides]

Welcome from another S30/Roadster owner. Sound like you have an ambitious plan there! The 4" of backspace should clear the inner fenders but each roadster is a little different. With those giant flares a 8" wheel will probably fit easily. Another member here, Nomadtrash (Andy) has I believe 15 x 10 on the back of his autocross monster and I think it has the Japco flares. I do not believe the Z brakes will cross directly over without modifications and forget about the booster, at least in a "stock" location. (Roadsters never came with one) For your motor choice, it sounds like your looking to go turbo? If so, crossflow is the (easy) way to go. I am currently turbocharging my U20 (similar to the L20) and it is an extremely tight fit with almost everything needing to be custom. (not that a CA or SR won't need custom stuff, just less of it) If you are looking for ease of installation, go with the SR20DET, as there are a few here that have done it and can help you along the way, especially Michael Spriso, the guy does amazing work! I am not aware of anyone here that has done a CA swap but that doesn't mean there isn't one out there. VH45? Anything is possible! Don't forget about the KA, probably an easier swap than the SR in some respects?

Mark

[olderthanme]

Chris66,
Thanks for the welcome!
The motor was just upside down

Welcome from another S30/Roadster owner. Sound like you have an ambitious plan there! The 4" of backspace should clear the inner fenders but each roadster is a little different. With those giant flares a 8" wheel will probably fit easily. Another member here, Nomadtrash (Andy) has I believe 15 x 10 on the back of his autocross monster and I think it has the Japco flares. I do not believe the Z brakes will cross directly over without modifications and forget about the booster, at least in a "stock" location. (Roadsters never came with one) For your motor choice, it sounds like your looking to go turbo? If so, crossflow is the (easy) way to go. I am currently turbocharging my U20 (similar to the L20) and it is an extremely tight fit with almost everything needing to be custom. (not that a CA or SR won't need custom stuff, just less of it) If you are looking for ease of installation, go with the SR20DET, as there are a few here that have done it and can help you along the way, especially Michael Spriso, the guy does amazing work! I am not aware of anyone here that has done a CA swap but that doesn't mean there isn't one out there. VH45? Anything is possible! Don't forget about the KA, probably an easier swap than the SR in some respects?

Mark

HAHA!
Well maybe I'll try to sell the booster and just build a different setup.
The SR20 looks easy as there are already mounts for it. I don't know if it would work with a FWD SR20 though. The RWD SR20 imported from Japan cost WAYYY too much for my wallet.

I have been looking into the KA-T setup as it can make some serious power but its a truck motor...
I'm looking to build a car that I can drive (maybe 5000 miles a year) and be very fun.
I'd eventually like to get to 300hp which should be ample for a 2000Lb roadster.

The VH45 is overkill I think... would be interesting though with the lack of traction

I have seen a couple CA swapped roadsters on the internet... Looks like a pretty good swap.
$1200 for a CA18DET with 5 speed seems like too good of a deal to pass up... Much cheaper tha the SR and makes decent power plus it sips gasoline when not in boost.

[Chris66]

Seems as a pretty cool engine
http://nscw.kolhoos.ee/eng/ca18det

[datsun1500]

Or you can turbo or supercharge a Zetec, plenty of room....
<A><IMG src="http://www.dealermats.com/zetec/thumbs/tn_1600_132.jpg">

[RC240z]

Welcome to the party from another Z car, roadster and 510 owner!!

R

[olderthanme]

Datsun1500 and RC240z

Thanks for the welcome and ideas!
Motor choice is up in the air so far.
2 liters or less and turbo is kind of what I am looking for in motor choice.
I have a Junkyard that has a flat rate price of $120 for a 4 cylinder engine and they go through a lot of different cars.

The FWD SR20 mated to an L series tranny sounds like the most promising (and cheap!).
The 280zx non turbo 5 speed tranny has some great gearing for higher cruising speeds.
With a 3.9 rear end gear and 225/50R15 tires with the 280ZX N/A transmission I'd be at 3,275 RPMs at 80MPH.
With a 3.7 rear gear I'd be at 3100 RPMs at 80.

Also the KA24 transmission will fit in an L series bellhousing(with a little machine work) and it is quite a bit stronger than the regular L series transmissions and has good gearing similar to the 280zx transmission.

FWD SR20DE (G20, 200sx, etc..) mated to a L/240sx tranny would be a sweet combo that I can get in one trip to the junkyard.

[RC240z]

One thing to keep in mind in a roadster, for performance is that you need to find a way to get the heat out of the engine compartment. His is a real challenge because of the small size of the engine compartment.

Also, because a Z car transmission is larger than a roadster modification to the tunnel is necessary as well. Most racers with a non vintage car choose to modify the floor and tunnel so the transmission can be removed through the floor of the car. Otherwise it is necessary to pull both the motor and the trans together to get to the transmission.

What do you plan to do to the rear suspension? four link? Ford 9" with floating axles? there are lots of options.

What are your ultimate goals a Hybrid Roadster?

Ron

[olderthanme]

One thing to keep in mind in a roadster, for performance is that you need to find a way to get the heat out of the engine compartment. His is a real challenge because of the small size of the engine compartment.

Ron,
Very interesting. Z car guys are trying to keep as much air out of the engine bay to reduce front end lift.(air pushes under the car at the firewall and radiator)
I guess some venting will be required since this is about the reverse of Z. No biggie though.

Also, because a Z car transmission is larger than a roadster modification to the tunnel is necessary as well. Most racers with a non vintage car choose to modify the floor and tunnel so the transmission can be removed through the floor of the car. Otherwise it is necessary to pull both the motor and the trans together to get to the transmission.

What do you plan to do to the rear suspension? four link? Ford 9" with floating axles? there are lots of options.

So basically the transmission tunnel can unbolt so that the trany can be lifted straight up? That is a pretty cool idea.
As for the rear end I am probably going to upgrade to a 3 or 4 link setup. I know lots about IRS from the Z car but still have some to learn with a solid axle.
My gut instinct is to get a Nissan truck C200 axle and shorten it so that it will fit in properly and mount it with a 4 link.
Read http://forums.nicoclub.com/zerothread/233955 for more info on Nissan truck axles.

A Clutch type LSD for a C200 axle is only like $400.

What are your ultimate goals a Hybrid Roadster?

Ron

Something I can drive occasionally and drive it over to Road Atlanta for track days. No particular class of racing. Hybrid is the name of the game...

Wheels will be 15X8 Diamond racing wheels with 4" of backspace (already own them) and 225/50R15 tires.
I might get another set of better looking wheels for the street and use the diamonds with race tires.

Thanks for the input guys!

Ron,
I love how your videos have the G forces overlayed on the video. I'm working on a similar project right now to do the same thing.


Dan

[RC240z]

Hi Dan, I think that if you stick to the live rear axle that the way to go is a Ford 9" as posi units and gearsets are easy to find and cheap. You might want to contact speedway engineering as they offer a solution that will have floating rear axles, disc brakes and a ford pumpkin that will be the exact dimention you require, after that all you need is a custom driveshaft.

If you look to to with an IRS your work is cut out for you...

Really the limiting factor of a roadster is the front suspension. The geometery is very restrictive from a modification standpoint. There is not the options that the Z car have available...

Heat soak in a roadster is a real problem, and can be overted with some louvers at the back of the hood and vents out the sides of the fenders.

Yes, my suggestion would be to make a removable tunnel to swap transmissions. It is easy to fabricate and much easier to deal with especially if you go with a turbo solution with a intercooler.

The overlay is really great as I can look specifically at a run and see if it is fast or slow based on many factors. including shift points and g forces. This is a GPS system and it works great. If you are interested I will PM you with the manufacture.

Good luck.

Ron

[olderthanme]

Hi Dan, I think that if you stick to the live rear axle that the way to go is a Ford 9" as posi units and gearsets are easy to find and cheap. You might want to contact speedway engineering as they offer a solution that will have floating rear axles, disc brakes and a ford pumpkin that will be the exact dimention you require, after that all you need is a custom driveshaft.

That sounds like the ticket. I'll look into the Ford 9" units. The 8.8 looks good too with similar parts availability and a little less weight.

If you look to to with an IRS your work is cut out for you...

Really the limiting factor of a roadster is the front suspension. The geometery is very restrictive from a modification standpoint. There is not the options that the Z car have available...

I don't think IRS will be worth the weight. Plenty of live axle rear ends can handle well and hold power.
Front suspenson is what I was thinking about. Maybe a custom SLA suspension is in order.

Heat soak in a roadster is a real problem, and can be overted with some louvers at the back of the hood and vents out the sides of the fenders.

Yes, my suggestion would be to make a removable tunnel to swap transmissions. It is easy to fabricate and much easier to deal with especially if you go with a turbo solution with a intercooler.

Cool. I'll add those things in the list of "to do" things.

The overlay is really great as I can look specifically at a run and see if it is fast or slow based on many factors. including shift points and g forces. This is a GPS system and it works great. If you are interested I will PM you with the manufacture.

Good luck.

Ron

The system I am working on a GPS and accelerometer based unit right now. Prototpe should be done by this summer. It also doubles as a sensor data logger and writes to a regular 2GB SD card.
I would like to see the manufacturer of your unit!

Later,
Dan

[RC240z]

This is what I use, it is complete and ready to use. It has a nice triggering device for LANC and a configurable lap timer.

http://www.hoyttech.com/index.cfm?fusea ... N=33157387

[olderthanme]

Here is an old video of some L series induction noises...with early SUs on my high(er) compression L26 (9.2:1).
I had just installed a Spec Stage 2+ clutch and 11Lb flywheel so I wasn't slamming gears too much. The car was a daily driver at the time.

http://www.dropshots.com/videolink.php? ... howVideo=1