Structural Limitation for 280Z

[Juiced]

Hey Guys I did a Search woth no luck, what it the tq/hp limitation on am unmodified 280z Body and frame.

 

Short Of going Tube Frame/12 point cage, what can be done to strengthen the chassis and keep it from bending like a bow tie?

[Tim240z]

Post in one forum per topic. Thanks.

Duplicate post deleted.

[deMideon]

sub-frame connectors are what you need... over what hp? I wouldn't know. Take a look at my yahoo picture album to see what I did. It made the car amazingly solid feeling.

[johnc]

Short Of going Tube Frame/12 point cage, what can be done to strengthen the chassis and keep it from bending like a bow tie?

 

Never seen one bent like a bow tie...

 

What is your intended use? Chassis requirements for autocross, drag racing, and road racing are different then chassis requirements for a street car.

[Juiced]

Actually i'm just going for Dyno Queen/ Freeway Supra Hunter w/ a FI SBC and Huge turbo prob a T6 flange

[johnc]

Put a roll cage in the car if you're going to be racing on the freeways.

[Juiced]

Do you mean a full cage, or just like a 6 point with door bars, or a 8 oint with 2 main hoops.

 

Does anybody have any experiance with the Jegs Tube Fraim Kit as far a assembly goes?

[johnc]

Full cage. If you're racing on the freeway you're going to have a wreck and it won't be a little one.

[Juiced]

I Live Out in Riveside County and on the Few Ocassion we do race on the freeway we pick a stretch of the 15 freeway@ 3 AM where there aren't any on/off ramps for 5 mile and it's pretty dam straight...

 

But i know what you mean.

[johnc]

I'm not trying to pick on you, but only occaisionally taking your car past 100 mph racing means you are most likely driving over your head. A midly evasive maneuver at 60 mph becomes a much bigger deal in a 240Z going over 100 mph. You have to be much more precise in your control inputs because you'll cover a lot more distance in the correction.

 

Spend a bunch of weekends a year at the drag strip, run a few HPDE events with an instructor, go to a Skip Barber or Bondurant school. Get used to the speed in a more controlled environment.

 

Regarding the structural improvements: Sub frame connectors as mentioned above seem to help along with triangulated strut tower braces in front and a straight brace in back. A welded in roll bar also helps with rear strength.

[Juiced]

I know and i respect what your saying... i actually have a 04 c5 vette and an 02 R1 as my DD and it use to by my race car (hence being tired of breaking transaxels) is there a power stering module available for Z cars. My 240 doesn't have PS and it would really help.

 

Any other sugestion to make the frame rock solid.

[wheelman]

So, do you have a 240 or a 280? There are significant differences in the body strength. A 240 is much more flexible than a 280 and requires more bracing, although the cages you've been talking about will go a long way to strengthening a 240 for any kind of torque you might throw at it.

 

You can use a Mustang or Subaru WRX power rack if you really need power steering but most people report that it isn't needed even with a "heavy" V8 installed. There are several threads on here that discuss this so do a search and they'll show up.

 

As for street racing, just don't be stupid and do it where there are others that get killed because of a mistake you make!!! We've lost several high schoolers in our area this year due to street racing accidents, one kid even ended up thrown through the window of a house when the car he was "riding" in flipped and he was ejected.

 

Wheelman

[Tim240z]

Well...if you get caught street racing in CA now, they just crush your car....not worth it...take it to the track

[Juiced]

Well thats good to know about the body diffrences. The car is a 71 240z.

 

Who makes a good 6-8 point weld in cage for the Z bodies. How about those sub frame conectors.

[Clifton]

Well...if you get caught street racing in CA now, they just crush your car....not worth it...take it to the track

 

That's reason enough to make a run for it.

 

 

Don't worry about it. I make over 500 rwhp and 500 rwtq in a 240 and don't have any problems. There are people making more in Z's without cages or of stiffening devices and are fine. The cars don't wrinkle up or twist into. Hell, Honda's are making 600-700 whp, some even more and don't self destruct.

[Mikelly]

Well I'm certainly no one's parent, and I have financial means that some may not have. But let me tell you WHY you may want to look into another hobbey with your Z, rather than road racing ilegally on public roads...

 

Here in Virginia there is a stretch of road where we used to test our project cars on high speed runs with the aid of a few of my former college buddies who are now State troopers or otherwise in lawenforcement. My degree was in criminal justice and I used to also be in law enforcement and what I'm about to admit to would have at one point thrown me in jail and removed my driving privelages forever... This particular stretch was on I95 between North Stafford and Stafford Rt.630 where there is no turnaround for 3 miles... We used two way radios and would get an 80-100mph start and make runs in the 150-170mph range late at night with no one harmed and no issues to worry about... At the wee hours of the morning that stretch of road was lightly traveled and there was no cause for concern. In 2000 I actually did some shake down runs with the aid of a friend in my 74 Datsun/383 stroker/ T56 combo car, the white flared Z. The downforces generated by the 930 style porsche wing actually caused stress cracks on the wing itself. Otherwise the car was fabulously stable. Anyway, Some kids that were hanging around at the time overheard me talking with someone on the phone (Actually a member originally from here, HybridZ) about the "testing" and they told others about it. Soon half the teenagers in the area wanted to do these runs and BOOM, Law Enforcement cracked down, taking some kids CARS in the process. Because I was plugged in, I never was subjected to that. BUt a lot of kids got big tickets, arrested, and lost licenses in the process, as the word didn't spread soon enough for some of them to abandon that stretch of road.

 

However, On February 2nd of this year I got popped with reckless driving in my 99 C5 Vette for spinning tires. The officer wasn't amused... and it was a wake up call for me... I was partially guilty but there was sand in the road and I DID have an issue with a false first gear kick back into neutral that helped, I just kept my foot in it AFTER it broke traction... Fortunately the judge agreed with me that improper driving was a more appropriate fine and conviction... But I talked to a few people in the insurance business, as well as law enforcement in Virginia about how strict they are becoming here and elsewhere in the country with those who speed... You're talking JAIL time, Loss of property, loss of license privileges, rediculous insurance rates (My stepson who is 17 is paying over $2000 per year for liability ALONE on a 1990 Civic HF Hatchback!), and huge fines/ legal costs...

 

I weighed the potential legal costs, and all of the above against ONE YEAR worth of track weekends and broke even on the cost, including gas and lodging... And insurance rates don't go down in a year... I've pretty much been broken of driving high speeds on our public roads. It took me until the age of 38 to "GET IT", but I did...

 

You can roll those dice if you want to, but I won't anymore... Now, Imagine if, While you're out racing that there is an incident and your car is involved in the death or injury of another person... Your life that you know right now, all the things you may take for granted, your job, the stability of your family, the obligations you have to your lendors, all that goes out the window... Is it worth it? for five miles and 3 minutes of fun? I'll spend the $400 on a track weekend and hit 150mph once per LAP for up to 8 thirty minute sessions and learn how to TRULY BECOME a MUCH better driver.

 

Just a view from the other side of the fence...

 

Mike

[randy 77zt]

i would rather spend money on a track day than in court.anything over 100mph in california is reckless driving.so watch out on the r1-the chp likes to impound things lately.for 30 days.

[Phantom]

Back to the original question which was about a 280Z - but you really have a 240Z? One thing about building what you are building is attention to detail. If you are not exact in what you do with what you are planning to do you'll end up dead - period. A 240Z chassis is not as rigid as a 280Z. I'm running 365 HP in my 280Z with just a 4-point roll bar and strut tower braces. It is proabably good for more but, at around 30 years old, these cars have done a lot of flexing and some of the spot welds have probably given up. A 240Z will require additional reinforcement.

It costs $15 to run at an NHRA track in Texas - all night long. It's safe, you get lots of friendly competition - and you get time slips to back up your bragging rights. Why would you want to participate in illegal street racing? Personally, I really don't give a %^*( if you kill yourself but I do care about the innocent driver in another car or a pedestrian that stumbles into it that gets killed or maimed for life. Keep it off the highway and on the track where it belongs.