Lola- A Father Son Z build

[aprophet13]

Hey guys I've read so many threads on here an have always wanted a 240z. Recently my dad and I decided to do a joint project on one. It is basically his car, but since I know a lot about these cars and how people modify them I am helping choose which parts to buy, and then I am installing everything I am able to.

 

Here's the car we picked up from a guy in Gilroy. 

 

It has a rebuilt L24 with a 280 5 speed. Even with the 2.4L this thing rips!

 

We're keeping it in my mom's driveway since that's where all of my tools are; I have a Volvo 242 project car I am already working on there 

 

Changed the oil and flushed the coolant

 

dropped the plastic wing nut from the radiator in there so it was fun fishing it out

 

I left for college and won't be back until spring break. My dad had me take the car to a shop so they could fab up a cage while I'm gone. 

 

Future plans for car:

Gnose bumper- ordered

fender mirrors- ordered

headlight lenses- ordered

ZG flares- ordered

BRE style wing- ordered

AZC track pack suspension kit- ordered

SR20DET swap- I know some people here would rather an L28ET/SBC but that's the route my dad and I have chosen

6 point cage- currently being fabbed

Bucket seats

Paint

RS Watanabe- still figuring out sizing

 

That's it for now just thought I'd introduce myself and the car

[OldAndyAndTheSea]

That's pretty awesome! So it sounds like this is going to be a dedicated race car?

 

Cool!

[BluDestiny]

Wow you dropped a lot of money on parts. I would probably have the cage guy also install new floor pans if you plan on having more than 300hp, which is cake for an SR. Also have you checked the frame or straightness? 

 

This looks like it's going to be a good build. 

[hwvigo]

Will be a very nice build can not wait to see the progress and im with BluDestiny on having the floor pans done. Happy building

[aprophet13]

Wow you dropped a lot of money on parts. I would probably have the cage guy also install new floor pans if you plan on having more than 300hp, which is cake for an SR. Also have you checked the frame or straightness? 

 

This looks like it's going to be a good build. 

 

Ya 300whp is just the mark we're aiming for. I think my dad and I are more set on weight reduction (opting for an SR vs RB) and I would even be happy with less. 

 

I'm only 18 but I do know a fair amount about modifying/working on cars, I just don't know the ins and outs of the Z specifically so tips like those are very helpful and much appreciated. I will definitely let my dad know.

[Leon]

Welcome! I'm close by in San Bruno.

[Pharaohabq]

Welcome...   A few things you might want to look at before they put in the cage.  A#1, you want to see what group/area you're going to be racing in. Make sure the cage conforms to that + the next group up at the minimum because you don't want to have to modify that cage after it's put in.  You can search on here about cages, but also contact the SCCA and see what their requirements are.  Since you're going with the SR20, you're already going to be out of a few classes. I think McKinney makes an SR mount kit for the S30. it's not cheap tho.

 

Next, you mentioned Seats, Well there's a lot to be said for buying race specific seats that are certified for your use. The seatbelts will also need to be changed. The stock ones are not good enough, especially at 40 years old.  You might also look at Bad Dog Rails for your chassis, they can tie things together and stiffen your body a bit to handle the HP you're looking to put down.  The R180 in the 240Z may be iffy at 300HP, but an R200 from any 280Z should be fine for that amount, though you might consider a different gear ratio, and a 5 speed from a later S130. 

 

Nothing you wrote mentioned Brakes, you will need to sort those before you buy your wheels, you may have fit issues otherwise. Not to mention you could upgrade the Stub axles to something thicker for the horsepower.

 

You've got tons of plans, but keep your budget.  Those Gnose kits are sweet, but they're notorious for needing a bit of massage for fit, so you might consult a body shop for that, unless you know what you're doing.  We can help you with so much of this, but keep a thick skin and think about your questions before posting.  Lastly, DL the FSM for your car, it'll help you more than you know, and it can be found free with a google search.

 

again Welcome to Hybridz, we're looking forward to your build...

 

Phar

Edited January 21, 2014 by Pharaohabq

[aprophet13]

Welcome...   [.....] build...

 

Phar

 

Phar, thank you so much for the detailed and specific response. A few things: 

 

We dont plan on using this for racing in leagues like SCAA (more driving occasionally for enjoyment) so the class specific info most likely will not apply to this car, how ever it is a good thing to keep in mind.

 

My volvo 242 already has a a half cage and recaro pole positions with status racing 4 pt. harnesses so I think i know pretty much what to expect in that area (but again thank you for the info)

 

The AZC includes 12.2" rotors I believe with 5 lug 5x114.3 hubs, 6 pot front and 2 pot rear? might be wrong on that. I agree that brakes should come way before horsepower which is why we are doing the cage, re-vamping the suspension/brakes before we even consider touching the motor. 

 

The car already has an r200 differential but I think the diff mounts from AZC require a q45 diff which is easy to score from a pick n pull

 

I'm so glad everyone is welcoming and eager to offer advice. Happy to be a part of the Z family!

 

-Adrian

 

 

[OldAndyAndTheSea]

Sounds like it's a road car? Why not opt for a nice (safer) roll bar, with harness provisions. Why do you feel you need a cage? Unless helmets are involved, I'd get a nice scca roll bar.

[aprophet13]

Sounds like it's a road car? Why not opt for a nice (safer) roll bar, with harness provisions. Why do you feel you need a cage? Unless helmets are involved, I'd get a nice scca roll bar.

 

Ultimately my dad is making all of the final decisions on this car and he wanted the cage. I think his reasoning was having bars that come by your side aid in crash protection since there are no side airbags and it is a 40 year old car. I also think he did it slightly for looks and kind of wants a race inspired interior. 

[OldAndyAndTheSea]

There are lots of debates on whether a cage is safe in a road vehicle. Padding or not. I'm sure your Dad has, but if not, he should really look into it.

 

Personally, I would never put a cage in any vehicle that wasn't a full dedicated FIA racecar. Just my .02, only trying to help.

[Pharaohabq]

You might read and have him read the threads on "Making a Z safer"  There was a lot of discussion on that, about how to limit body motion and impact inside of the car.  That is using crushable door bolsters and preventing your body from flying around during an accident.  Think of your body in the car sort of like your brain in a concussion. You don't want the inside of the skull to  damage the brain (your body)  so good seats and body acceleration prevention.  Also updating things like the brakes and seatbelts are all good suggestions.  In the end though we noted that driver attention and reaction are the #1 ways of preventing injury. Aside from that it's knowing how your car works and what it's capable of.   There was the vehicle intrusion issue which was never really addressed, but broadside hits are always going to be an issue even in modern cars.  Read up on it and ask questions, maybe we can get it answered.

[MidnightCafe]

What plans do you have for the 6 point cage-are you looking at any designs available online? I was thinking of a 4 point cage, since seeing a fellow Z owner's 6 point cage and his complaints about interior space. But like you said, crash protection on a 40 year old car is important...

[SDgoods]

Welcome.   I street drive  my Z and agree with the above statements that a full cage is unecesary and even dangerous with out a helmet..

 

This is my 100% Bolt in custom roll bar.  It was really important that Id be able to remove it if I ever needed/wanted to.  And as you can see, its still pretty beefy.  I would continue to read up on other members experiences with cages and roll bars as, its a very  prevalent and significant factor in the drivers and passengers safety. 

 

 

 

Edited February 3, 2014 by SDgoods

[clocker]

If we stipulate that we're talking about safety in a street driven car, looking to race required tech is a dead end.

Only the truly hardcore would be willing to crawl in the window, strap on a five point harness and helmet, just to make a beer run.

Thinking more radically is required.

 

The first "radical" thought is the realization that looking through a modern lens, the Z bodyshell is a crap design.

With our '77 stripped completely bare I've had the opportunity to get a good look at it and compare/contrast to my daily RX-7 (which is only 14 years newer), the differences are striking and obvious.

 

Metallurgy and technology now allow for much larger and deeper drawn stampings than were possible back then, so the Z body has many more small pieces making up its structure. It is inherently weaker because of this.

The Z has a floating windshield and so loses the structural integrity that a glued in glass panel provides.

 

Worst of all though is the absence of a b-pillar.

It's no wonder that Z's tend to crack where the rear sail panel joins the roof, the whole car basically hinges right there.

 

Since a street car hasn't the luxury of building a whole new structure inside the bodyshell (i.e., a cage), the next option is to strengthen the shell itself.

Two approaches could be used together.

 

First, stitchweld the whole body (this all assumes the body is in good shape and intact...we're beyond rust repair at this point).

That alone probably increases torsional rigidity by 15-20% on an old shell like ours.

 

Second, using sheetmetal box sections, reinforce the bodyshell following the same basic path as a cage but attached to the shell, not freestanding. This would include the rocker area and some sort of b-pillar "roll hoop/targa bar".

I am a fan but not a practitioner of the metal forming arts, but I've seen enough build threads to know that this would be technically pretty straightforward, it's the aesthetics that would be challenging. Especially the b-pillar bit.

 

I would allow the five point harness to be swiped from the racers bin of tricks.

Not only would the shoulder harness bar provide some structural strength to the chassis but the fact is if you are ragdolling around the interior at impact, it hardly matters how strong your shell is.

 

In a world full of Escalades, the Z just is what it is and there's not much you can do about it.

When you're driving around with your head at everyone else's bumper height, the strength of the body hardly matters.

[aprophet13]

I appreciate all of the responses guys, its nice to see people offer helpful feedback.

 

I wil definitely talk with my dad and rethink what his priorities are/if he really wants a cage put in.

 

In other news, some parts have started to show up!

 

Billet suspension parts from AZC:

 

 

Gnose Parts:

 

 

Cant wait to get back over spring break and start working on this thing

 

-Adrian

[Pharaohabq]

You're dropping for good $ on parts.  I hope the body you have is as sound as you think it is.  It's great that it's something you and your father get to work on together.  It should be one of those treasured memories deals, and a car that's going to have special meaning for you. 

 

Clocker mentioned methods of reinforcement that doesn't include a cage.  I Agree, in that I've seen some really nice builds where people have not only stitch welded all the seams, but they took panels from other cars  and cut out corners and sections and welded those over the same portions  at various locations, at some points 3-4 layers of metal to re-enforce the frame to effectively stiffen the chassis without having a bulky cage.  The advantage there too is that many of the body interior panels could then be modded to fit as though there were no modifications in place.  Note that I'm not talking full panel replacement, I'm talking 3-4" wide strips that are welded over the existing panels to make something of a integrated cage. A hoop could be integrated at the area across the top of the hatch which should be back far enough to prevent your head from contact. The focus would be in retaining the stock look and stiffening rather than directly safety. 

 

Multiple layers up around the "B" pillar  may not be a bad idea from the chassis intrusion perspective. Though an integrated Door bar as seen in newer cars may be an idea.

 

 

This would in no way be SCCA or any way certifiable, but it could certainly stiffen things up a bit. Especially if you integrated those Bad Dog Rails. it would not preclude you from putting in a certifiable cage either.

[aprophet13]

I have actually been researching both stitch and seam welding this week. It appears that most people recommend stitch welding all of the seams like you stated. I guess this is to minimize warpage and time while still maintaining strength. 

 

I have also been learning to TIG weld in the workshop at my school (although I've read that MIG is usually better for stitch welding? because of less heat?) and I think it would definitely be a worth while endeavor.

 

thanks for the helpful input,

-Adrian

I Agree, in that I've seen some really nice builds where people have not only stitch welded all the seams, but they took panels from other cars  and cut out corners and sections and welded those over the same portions  at various locations, at some points 3-4 layers of metal to re-enforce the frame to effectively stiffen the chassis without having a bulky cage.  The advantage there too is that many of the body interior panels could then be modded to fit as though there were no modifications in place.  Note that I'm not talking full panel replacement, I'm talking 3-4" wide strips that are welded over the existing panels to make something of a integrated cage. A hoop could be integrated at the area across the top of the hatch which should be back far enough to prevent your head from contact. The focus would be in retaining the stock look and stiffening rather than directly safety. 

Edited February 11, 2014 by aprophet13

[Pharaohabq]

Yeah MIG is really better because of the Heat, and the ease of welding large areas. Tig is awesome for finer detail and specialty metals like stainless and aluminum. You'll be great at making your exhaust if you're good with TIG. for stitching where you're stopping and starting many many times to keep the heat down you'll be much much happier with a MIG.  You might want to talk with your instructor and see if you can get some body panels to practice on. it's really easy to burn through. If you can, use a sppon on the backside to help prevent that.  

 

Clocker had originally stated about Stitch welding the seams, I was talking about area re-enforcement.

[seattlejester]

It looks like you are off to a good start, those are some nice bits you are ordering there!

 

I am on the same boat, a full on cage is a bit silly for a road car, but even more so, a full on cage is a pain in the ass to climb in and out of especially with door bars, it is a constant game of leg first, ass, head, then grabbing other leg with both hands and bending it to get in. Not a fun game after a while. 

 

Some reinforcement would not go awry. I, like many others, have seen inherent flex built into the chassis, but just some corrections...

 

Metallurgy hasn't changed much in that time frame, mild sheet steel is still mild sheet steel, metal working on the other hand has changed a great deal.

 

I want to say the roof to rear quarter panel tends to crack, not because it hinges but because it is soldered/filled in that location with lead. The same phenomena can be seen at the windshield gasket where solder is also used.

 

I am not sure about integrating a targa bar into the chassis in that area as in a side collision your car would no longer receive impact at that point, it would be more likely to crack or deflect momentum into the seating area. 

 

I wouldn't be so bold as to put a % on stitch welding, I want to say mercedes added a couple hundred extra feet of welding to one of their cars and vibrational analysis showed a modest gain of ~10% (granted that is a more modern car).

 

5-point is actually frowned upon now a days, 6 point is much more preferred. A much nicer compromise for the street is a 4 point harness with anti submarining, a 4 point is still relatively easy to get in and out of. Or alternatively a retractable wheel for the shoulder harnesses like schroth sells, would still allow you to move about if you needed to reach for something, like the window crank while you are sitting in traffic. A regular 4 point is actually deemed dangerous, it would be better to use it as a 3 point.

 

Now that all that is out of my system...

 

The q45 swap is much more than just the diff! Make sure and do a lot of reading, if you choose to go that route, it is fairly intensive. Usually involves a full strut hub etc from the donor vehicle as well as custom shortened axles.

 

Stitch welding with a mig will be easier for the whole car, as mig's tend to be smaller so it will be easier to move around the car and if you have to you can weld with one hand for awkward locations or if you are using one hand to hold yourself up. Personally I like it because you can kind of keep your face away from the work, I feel like I get a lot more sparks in my mask when I am working at tig level distances. I stitch welded my front towers, but it is a lot of work to get the undercoating off everywhere to do a good job on the bottom of the car and other areas.

 

I like the overlapping panel idea, maybe a lot of work to clean the panels and such, but it would be a pretty neat way to double up on thickness. Granted you would have to do some spot welding for the curved portions so make sure there aren't any "bubbles."

 

I think the concensus is that we all want you/your dad to reconsider doing a full cage for a road car. In the end it is your decision, but just the group opinion. 

 

Keep us posted, the parts list makes me really excited for the build!