240Z Headers

[240zdave]

I'm looking for companies that make headers for a square-port 240Z. I've seen what Motorsports Auto, Victoria British, PaceSetter, Arizona Z-Car, and Stahl have to offer. I even found some Nissan Comp headers. I'm hoping to find someone that makes stepped headers (1-1/2" at the flange, stepping up to 1-5/8", then 1-3/4", into 2-1/2" collector). Hooker and Hedman don't appear to have anything. Any suggestions?

[lateapex911]

On this site, "Katman" and "joe harlan", (and sorry to others I didn't think of off the top of my head) are the experts in that area. Might want to PM them.

[JeffYoung]

One other place to check is Steve Parrish in the SEDiv. I believe his handle here is Parrish57. Sweet silver Z that sounds like no other one I have heard. He may have some contacts for his headers.

[Parrish57]

Shhhhhhh .... Lets not give away all of my secrets! :018:

David... Email me at [email protected]

[kthomas]

How much money do you have to spend, and what is the rest of your engine program like?

The closest thing commercially you'll get to what an ITS 240Z motor wants is a Stahl with 1-1/2 primaries. Tell Jere your application. You don't want steps up to 1-3/4, waay too big. Our ARRC's were won with a Tri-Y that had less than 1-3/8 ID primaries, 2 inch OD secondaries, and a single 2-1/2 final. 200+ SAE "East Coast" ponies. Most people have way too much header on their ITS cars (and way way too much on their street cars). Sunbelt's final ITS 240Z motors made 205-208 with a custom, stepped, Tri-Y header. About $1500 might get you one.

There's more power to be had in dyno tuning than there is in headers. We tested them ALL, at least 12 that I can remember, and various combo's of exhaust pipe. We always made more horsepower in a day with the carbs and tuning than we did with headers. I guess my point is they should be one of the last things in your program (driver, suspension, engine, tuning) to sweat. But if you have Pacesetters, MSA, Hooker, AZC it's worth sweating- they're NFG for ITS.

The next best thing to a Stahl that is *sorta* commercially available would be an old Clifford Research or BRE (was part of the "Whisper Power" system back in the 80's). Both are 1-1/2 primaries about 26 inch long but you'd be hard pressed to find one anymore. I did have the guy who actually builds NISMO's headers make one for a similar app to ITS- same exact header as the NISMO Comp but in 1-1/2 instead of 1-5/8. If pressed I could probably source one again.

I'll have to PM Steve Parrish and see if he's barking up the same trees we did. :)

[Andy Bettencourt]

Now THAT was a freakin' informative post!!! Now if the KAT can find me a supply of inexpensive rust-free donors, I usher in a new era in ITS up here in the NE!!!

[JeffYoung]

That was a good one.

Kat, what do you think of the 260z at the new weight?

[jmark]

http://www.stahlheaders.com/Frame%20New%20RR.htm

[kthomas]

Now if the KAT can find me a supply of inexpensive rust-free donors, I usher in a new era in ITS up here in the NE!!!
[/b]

Gee, I have one of those (rust free donor, '71) that needs a home....

I haven't been paying attention- what's a 260Z weigh now? Things to think about before considering: The L26 was same bore as an L24 but with what eventually became the L28 crank. Torque will be more, but proly at a lower rpm. It's our experience that more useable rpm gives you the ability to gear numerically higher, which is a torque multiplier to the rear wheels- which almost always is faster and more useable than engine torque made lower. I like what 7400 rpm all day long does for us (well, once we figured out how to make the numerically higher diffs last). Doubt you could do that with an L28 crank and cast pistons, maybe with forged. If it was only 50 lbs difference I'd still bet on a 240Z. Yeah, we had a big time engine program but I'd attribute our success to chassis, and weight hurts.

[x-ring]

The new weights are 2430/2480/2505 for the 240/260/280 for a 50 and 75 lb weight delta over the 240.

[JeffYoung]

I believe it is 50 lbs more than a 240z.

Our 260z revved pretty easily to 7000, but it is a car we bought from a guy in Atlanta and I have doubts about the legality of the cam in it.

Nor do we even know how to get it down to 2480 or so. It weighs 2600 plus at this point, and that's with the small bumpers, reasonable fuel cell, aluminum drums, etc.

[Ron Earp]

Yep, it is hard to tell with that 260z motor what we have. The car drove pretty well and was a lot of fun, well done cage, good bits, and a fresh engine. But that dang thing didn't do much of anything until 3200 RPM, and then it wanted to go to 7+ which I thought was uncharateristic of a 260z, or 240z for that matter. All I know is on the straights at VIR if you'd held the hammer down it'd keep pulling quite high in the RPM range, you had to force the shift for fear of something letting go.

Then again, it might be the blasted flat top carbs. They are horribly rich at idle and low RPMs, could be the air fuel is finally getting right at the upper RPM range which makes it feel like some strange cam. It is fat and lazy below 3000 RPM.

R

[DoubleXL240Z]

Ok!!! I just learned more about my project in 10 minutes, than I have in the last 2 months!!!!
Thanks!!!!

[kthomas]

Oh, I forgot about those post '73 boat anchors they call carbs. Eddie Radatz at ERadatz Motorsports is the only guy I know that has ever made them work, but now reason why you shouldn't be able to idle AND race, even with those carbs. A lot of ITS Z folks run WAY too rich, which is why the cars won't run worth a crap below 3k. In the L24 we had trouble keeping them lean enough until about 6500, and then we had trouble getting them rich enough. Had to have custom needles and really monkey with the damper springs and fluids. No substitute for a week on the dyno with the right instrumentation.

We came in second one year at the ARRC with 40 hp less than what Sunbelt eventually got out of the ITS L24 program (and people thought we were cheating at 165 hp!). Almost all of that difference was learning how to burn ALL the gas.

[jmark]

Does Eddie Radatz at ERadatz Motorsports have a website?

[kthomas]

Eddie is, how do we say, Old School. He's in Marietta, GA at 770-926-6621.

[JeffYoung]

K, amen on that air/fuel thing. Our Z is EXACTLY like that. So rich at idle that it barely runs, and then wakes up around 3-4k. Like Ron said, we used to think it was the cam coming on, but maybe it is the carbs just getting right.

What is the difference between teh flattop and roundtop carb? Essentially the same CD design right? In looking through our documentation on the car, it looks like Mr. Radatz had a hand in our carbs, so maybe we got lucky.

Air/fuel issues on a CD carb seem to me to be the secret to power. I put richer needles on the TR8 and it really woke up up high. Cured a high rpm miss, that scarily enough was probably from a very lean condition.

The joys of working on ITS dinosaurs....

[jmark]

Eddie is, how do we say, Old School. He's in Marietta, GA at 770-926-6621.
[/b]Just checking..... I know he originally built my friend Greg Ira's EP 240Z which is still winning races. Greg set the track record last weekend at HPT first time there. Car has set track records at Sebring, Homestead, and VIR this season.

Car sounds sweet.

http://s19.photobucket.com/albums/b163/jma...straightVIR.flv (http://s19.photobucket.com/albums/b163/jmark240z/VIR%2006%20Oak%20Tree/?action=view&current=EPCarfrontstraightVIR.flv)



Some pics I took at VIR this year. I can't wait for the Runoffs.

http://www.classiczcars.com/photopost/data/505/DSC_0940.JPG

http://www.classiczcars.com/photopost/data/505/DSC_0921-1.JPG

http://www.classiczcars.com/photopost/data/505/DSC_0871.JPG

[kthomas]

Greg:

What size tires are those? Ride height seems a little high for an EP car. Body roll seems a little excessive too. What springs? Does that car still have the ShockTeks? PM me, maybe we can go faster!

[Parrish57]

The closest thing commercially you'll get to what an ITS 240Z motor wants is a Stahl with 1-1/2 primaries. Tell Jere your application. You don't want steps up to 1-3/4, waay too big. Our ARRC's were won with a Tri-Y that had less than 1-3/8 ID primaries, 2 inch OD secondaries, and a single 2-1/2 final. 200+ SAE "East Coast" ponies. Most people have way too much header on their ITS cars (and way way too much on their street cars). Sunbelt's final ITS 240Z motors made 205-208 with a custom, stepped, Tri-Y header. About $1500 might get you one.


I'll have to PM Steve Parrish and see if he's barking up the same trees we did. :)
[/b]

Katman

It sounds from your description like I found a header similar to the one you were using for the ARRC wins. When I switched from a step header with two 2 1/2 inch collectors to the single 2 1/2 it really picked the motor up. Keeping up the exhaust velocity seems crutial. Everyone at the track noticed right away because the sound of the car changed dramatically. I'm still turning about the same RPMs but it sounds like it's 1000+ RPM higher.

Now if I can find out where to get the needles you ended up using then maybe I wouldn't have to bark up sooo many trees!

Steve

[kthomas]

Hey Steve:

What the engine needs is a needle shaped like a dowell pin, and an SM is definitely out. I think the closest unmodified was an N54, I'd have to go back to my notes. Doubt Sunbelt would let out what we really used.

We were anal enough early on to actually mount a camera pointed into the carb during dyno runs to see what the piston was doing. In stock form the SU's are pretty much slammed to the top by 4-4500 rpm at WOT, so the needle isn't doing anything. Part throttle like most street driving is an entirely different kettle o' fish, and contrary to popular belief there is no part throttle (i.e. no squeezing on the throttle, that's for wimps) when racing a Z in ITS, unless you're driving to the grid (or you don't have the chassis nailed down). So, to make the needle effective, and thereby maintaining something like an optimum AFR, you have to slow down the piston. Very tricky balance between restricting airflow versus optimizing AFR. The AFR will vary somewhat just by the velocity over the bridge, so it's not like you want redline to equal piston at the top. You can let it get there sooner than that. Cool, huh?

[JeffYoung]

So once you get the needle profile squared away, the work is in then in the piston springs and damper fluid?

On my car, my carb pistons are at the top of their travel VERY early in the RPM band. I am assuming based on the above that this is not a good thing?

[Parrish57]

Katman.....

Very Cool!! Thanks for the tip. If I recall, some of the video you shot of the carbs ended up on the Z Therapy tuning video. I've recently caught on to the concept that having the piston slam to the top quickly was a bad thing. I just haven't nailed down the ratio. Of course there is a reason for that- it's called work.. Perhaps you can help me with this equation:

Work x $=No time vs. no $=no race

It seems that when I go WOT at work I have plenty of money but no time to race much less development. Do you happen to know Wednesdays Lotto numbers?

Steve... On the road until the 22nd- Amsterdam, Frankfurt, Dubai, Shanghai, Baku, Frankfurt, Dubai, Dhaka, Dubai, Amsterdam, Philidelphia, Home (Charlotte)

[seckerich]

Hey Steve:

What the engine needs is a needle shaped like a dowell pin, and an SM is definitely out. I think the closest unmodified was an N54, I'd have to go back to my notes. Doubt Sunbelt would let out what we really used.

We were anal enough early on to actually mount a camera pointed into the carb during dyno runs to see what the piston was doing. In stock form the SU's are pretty much slammed to the top by 4-4500 rpm at WOT, so the needle isn't doing anything. Part throttle like most street driving is an entirely different kettle o' fish, and contrary to popular belief there is no part throttle (i.e. no squeezing on the throttle, that's for wimps) when racing a Z in ITS, unless you're driving to the grid (or you don't have the chassis nailed down). So, to make the needle effective, and thereby maintaining something like an optimum AFR, you have to slow down the piston. Very tricky balance between restricting airflow versus optimizing AFR. The AFR will vary somewhat just by the velocity over the bridge, so it's not like you want redline to equal piston at the top. You can let it get there sooner than that. Cool, huh?
[/b]
Good information KT. Did you find that you had to tune the dash pots with the springs and just use the fluid for damping the fast throttle hits? On our old GP and FP triumphs we used the jet size for the base curve and turned blank needles from there to fix the flat spots. We used a modified set of dashpot caps with indicators to check travel. Never found we needed the pistons all the way up until you had some long pulls. Great information you have shared--thanks.

[Ron Earp]

On my car, my carb pistons are at the top of their travel VERY early in the RPM band. I am assuming based on the above that this is not a good thing?
[/b]

Could be good or bad I think. I think it'll depend on how much air the motor needs and the diameter of the venturis, as well as some other things like the cross sectional area of the slide blocking the venturi.

I'm thinking of it this way - if you had say a 1/2 inch hole feeding half your motor you'd need that carb wide open quickly to provide enough air for the motor at any reasonable "race" RPM. If you had a 3 inch hole, well, opening the slide all the way straight away is not going to be good for power production.

In both cases the size of the hole will affect air velocity through the venturi and how much fuel is pulled up too. Looks like we need some time on the dyno!

Good info in this thread, nice when folks share and don't throw red herrings out all over. Thanks!

R

[lateapex911]

....

Steve... On the road until the 22nd- Amsterdam, Frankfurt, Dubai, Shanghai, Baku, Frankfurt, Dubai, Dhaka, Dubai, Amsterdam, Philidelphia, Home (Charlotte)
[/b]

OK, none of my business and all that, but what the heck do you DO??? Dubai THREE times? In the next week?? With 12 other stops around the world???? I hope you at least started this trip a bit ago! hate to see the bill for those flights!

Unless..............you're a pilot!? yea, that's gotta be it...right?

[kthomas]

Perhaps you can help me with this equation:

Work x $=No time vs. no $=no race

It seems that when I go WOT at work I have plenty of money but no time to race much less development. Do you happen to know Wednesdays Lotto numbers?
[/b]

That's a tough one. But I have figured out an equation for why my managers make more than me:

Time = Money. Knowledge = Power. We all know the derivative of work with respect to time is also equal to power. Or, Work/Time = Power. Substitute Knowledge for Power, and Money for Time:

Work/Money = Knowledge. Then solve for Money: Money = Work/Knowledge. Therefore, the smarter you are, the harder you have to work, or the less you know the more money you make.

[Parrish57]

OK, none of my business and all that, but what the heck do you DO??? Dubai THREE times? In the next week?? With 12 other stops around the world???? I hope you at least started this trip a bit ago! hate to see the bill for those flights!

Unless..............you're a pilot!? yea, that's gotta be it...right?
[/b]

Ding ding ding.... We have a winner! I fly a 747-400F. If I got frequent flyer miles I'd have enough for a round trip to the International Space Station. We do a lot of contract stuff for Emirates Sky Cargo so Dubai is like my second home.

I knew I should've stayed awake in Algebra class.

[Ron Earp]

Here you go, written up in the commonly seen Dilbert way as it appeared in the cartoon:

DILBERT'S THEOREM ON SALARY:

Dilbert's Theorem on Salary states that engineers and
scientists can never earn as much salary as business
executives and sales people.

This theorem can now be supported by a mathematical
equation based on the following three postulates:
Postulate 1: Knowledge is Power (Knowledge=Power)
Postulate 2: Time is Money (Time=Money)
Postulate 3 (as every engineer knows): Power = Work / Time

By substitution, since Knowledge = Power, Postulate 3 becomes:
Knowledge = Work / Time

and since Time = Money, we have:
Knowledge = Work / Money

Solving for Money, we get: Money = Work / Knowledge

Thus, as Knowledge approaches zero, Money approaches infinity,
regardless of the amount of Work done.

Conclusion: The Less you Know, the More you Make.

[DoubleXL240Z]

OK, so the way I see it is:
If I don't understand any of this!! I should be a millionaire at least!!!!
So, all I have to do is find the genius to give me all his money!!!
Whew!!! Why did I study in school???... Did I study in school?????

[lateapex911]

Dilbert is brilliant! And has no money.