LS1 powered S14 with motorplates and modded GTO pan

[SicBastard]

Thanks for the tips on the ball joint parts. I'm pretty sure that the stock hood is 53 lbs! I know kognition once made a non-reinforced, dry carbon hood that was only 8 lbs. That's huge.

[SicBastard]

My miata is on ebay now, tell everyone you know who needs a 300 hp, 2200 lbs, whipple charged monster, that the funds will go to the good cause that is a 404ci L76 powered 240sx.

no reserve.

No Ebay Sales

[stockbee]

Definitely awesome build going on here still. Since you all were on the subject of ball joints, what ball joints you guys would use to replace your rear lca ball joints. AAP, and O'reillys doesn't have a part # for a rear replacement.

Would a front replacement work?

[SicBastard]

Can't help ya with stock replacement, I havn't replaced them yet. On some cars you have to buy a whole damn new control arm! Sounds like a good time to weld in a mono ball race (to replace the ball joint) for some roll center correction in back. Then you could actually tune your Roll Axis!

[Otto347]

Originally Posted by SicBastard

I'm seriously thinking about it.

Or you could use UB machine part #40-4185-075 but that will require you to ream the stock spindle to a 7° taper. But its a 3/4" shank (no adapters) and the 7° stud is pretty massive comparted to the other setup.

[SicBastard]

Thanx for the part # Otto.

I stumbled accross these gussets the other day. I think my roll cage Neeeeds them...







available here

TMR Customs, Custom Fabrication Components for Offroad Vehicles

[95KA-Turbo]

Originally Posted by Otto347

Or you could use UB machine part #40-4185-075 but that will require you to ream the stock spindle to a 7° taper. But its a 3/4" shank (no adapters) and the 7° stud is pretty massive comparted to the other setup.

[img]http://otto-fab.com/pics/07.05.2010_new_mono_stud.JPG[/]

Does that allow for more adjustment then the Speedway Motorsports studs?

[SicBastard]

Originally Posted by 95KA-Turbo

Does that allow for more adjustment then the Speedway Motorsports studs?

It's hard to tell. Here's the specs from speedway. I could only find one entry under steering, and none under suspension.


GM:

• Stud is 5-1/8" long
• Steering arm end has 7/16" thread
• Tie rod end has 5/8" thread and is 3" long with 2-5/8" of thread
• 10 degree taper

Pinto:

• Stud is 4-13/16" long
• Steering arm end has 1/2" thread
• Tie rod end has 5/8" thread and is 3" long with 2-5/8" of thread
• 7 degree taper

And here's UB Machines largest 3/4":

40-4921
Stud for metric lower ball joint - 3/4" monoball
5" long
$18.30

But they do make upto 5.5" long:

40-4117-075
Stud for GM press-in - 3/8" longer & 3/4" adjustment
5-1/2" long
$20.00.



Knoop is that the speedway part# you used, pinto or GM? You said you couldn't go more than another 10mm even if you wanted to with 17" wheels, correct?

[SicBastard]

There's alway custom too. A good machinist should be able to make whatever length you want.

[95KA-Turbo]

Shit, I guess I have the Pinto one as mine is a 7 degree taper. So I guess the UB Machine one would give you a little more adjustment.

The adjustment isn't limited by my wheels so much as it is by my brake rotor. I can adjust mine another 10mm but it will hit my rotor (and I already had to grind down my LCA to clear at this level of adjustment). In reality, probably need another inch of adjustment to get my suspension geometry correct, lol.

I noticed at ECB this past weekend my car feels fairly twitchy, the rear comes around a lot faster then I remember and it doesn't feel quite as stable as it used to...then again I am making 72 more whp then I was with the SR, not to mention the torque or the powerband. The new front tires helped out a whole lot...I think I mostly just need more seat time. I think I just now decided I am not going to rip my damn suspension apart again, lol.

[SicBastard]

A little more toe-in, both front and rear, and a bit more suspension travel with progressive, short, bumpstops might make that twitchy-ness go away. Other than the bump stops, you wouldn't have to take anything apart. What alignment settings are you running now?

[95KA-Turbo]

-2.7 camber up front with 0 toe
-1.4 camber out back with 0 toe

I have always run 0 toe and liked it, I changed my spring rates from 9k/7k to 10k/9k and I am not running a rear swaybar. I know there is no way I am hitting my bump stops on the shock, since I have it so low and its lowered by the shock body.

I know the front was rubbing agains the back of the fender well pretty bad at full lock, so I flipped my camber plates to move the shock more forward and shortened my tension rod to get the caster back to how it was (probably only around 6). I am just trying to decide if I want to go ahead and replace my inner bushing on my LCA with a heim joint right now. I just need the weld in threaded insert, I already have some 16X2.0 aurora heim joints.

[GSXRJJordan]

Camber is fine, and 6* of caster should work out pretty well depending on tire size. I also run no toe, but all the FD guys play with a little toe out in front and very often roll with toe in for the back.

Why the hell would you run 10k/9k rates on such a light car with street tires? Might as well not have dampers. You're missing out on a ton of traction... the KW's that the FD S-chassis use have MUCH softer springs.

[SicBastard]

If it's not your bumpstops limiting your travel what is!? Are the tires bottoming out in the wheel wells, or are the control ars hitting something? Either way, every time that happens your 9k spring rate goes to infinity instantly.

ANY rear wheel drive car with more than 200 hp must have some toe in in the rear. Otherwise the natural forces on acceleration cause dynamic toe out, a way unstable situation. Zero toe in front is nice for turn in, but just a little toe in will increase straight line stability.

A rear sway bar will also equalize the pressure between the rear tires on accelration. This should increase predictability with what the rear is doing. The drag racers run rediculously large rear sway bars because it decreases 60' times. If you're running a dual exhuast that won't fit with a 240sx sway bar, a z32 sway bar has a second cut out for dual exhaust, though it may take some custom work to attach it to the RLCA. When ever adding a rear sway you usually have to decrease the spring rate on that end.

[GSXRJJordan]

Lol wheel wells are limiting travel for sure.

Lots of people run no toe in the back. Dynamic toe is adjustable via the traction rod.

When running spring rates that high, sway bars don't do anything. You're not getting any appreciable compression anyway.

[SicBastard]

The art of bumpstop tuning is seriously underutilized with the Nissan camp. Tuning bumpstops is as important as spring rates and damping in a car with that little travel. You may have to buy shorter springs so that you can raise the shock body. Or you can have aluminum spacers machined to take up some of the space between the damper body and bumpstop that slides over the shaft.

[95KA-Turbo]

I got the higher spring rates because the car felt too soft on the 9k/7k set up.

I never really thought of what's stopping the shock under compression...clearly in the front its the wheel at full lock (I guess the bump stops do it under normal driving). Out back the control arms hit my chassis before the wheel does, but I haven't had any issues with that....not to mention my exhaust would hit the ground first and I don't recall hearing any scraping.

I was under the impression when you hit the bump stops your spring rate goes to infinity anyway....I guess that is not true?

[SicBastard]

You're also out of your mind if you think that a rear sway doesn't contribute significantly, even in a car running almost 600 lb/in springs.

10kg = 564 lb/in
9kg = 506 lb/in

I plan on runnig the largest front bar I can find ~32mm, and I have a pair of z32 bars, the largest is from a 300zxtt at 26mm.

Shaikh J. Ahmad of FatCat Motorsports has a nice convenient worksheet you can play with. It is specifically for a miata, but the miata has wheel rates that are almost identical the the 240sx so it works fine. You can of course bust out your own excell program if you want it a hair more precise.

FCM_MSDS_1_6NA.xls

A car running 10/9 springs with a 32mm front sway bar and no rear sway has a (too high) front roll couple percentage of 61.5%. Slap a 26mm rear bar on at it falls to 38.9% !!!

Ideal is generally 48-58%, but there are of course exceptions. My miata (which carries 53% of it's weight on the nose with the supercharger) didn't seem dialed until I found the thinnest rear sway I could find (11mm), that got my front roll couple percentage to 58.9%.

Z32 Rear Sway Bar Sizes:
ALL TTs: 26mm
2+2 NA: 20mm
2+0 NA/Slicktop/Vert: 16mm

A set up I'm considering is 8/5 (450/281) with a 32mm largus in front and a 20mm Z32 rear bar. Should net a front roll couple percentage of 57.4%. I'd eventually like to try and the 26mm rear bar, and then balance the car with a custom front sway bar using circle track parts. With the same spring rates (8/5) and the 26mm rear bar, I'll need a 41mm (1.6") front bar to maintain a front roll couple percentage of 58.7%!

[SicBastard]

Originally Posted by 95KA-Turbo

I was under the impression when you hit the bump stops your spring rate goes to infinity anyway....I guess that is not true?

Not true at all. That's actually the point of the bump stops. As you tune the bump stops you tune how fast, and at what height the spring rates approach infinity.

Here's a graph of force vs compression height of three different bump stops
Notice they all eventually go vertical.

http://www.fatcatmotorsports.com/iga...6_46_stops.GIF



If your car isn't bottoming out on the bumpstops you're not controlling your last inch of suspension travel. This gets all the more critical as you lower your car to the point that you might only have 1 inch of travel!

[95KA-Turbo]

My only problem with running a larger rear sway bar is my exhaust is 4" under the bar and its been flattened out into an oval at that spot and it currently almost touches the stock S14 rear sway bar.

I am running the Sikky front sway bar which is a solid 32mm one (I have the old one, apparently the new one is hollow and like 30lbs lighter).



That bump stop graph is pretty interesting....so basically the smaller the bump stop the quicker you hit coil bind? I guess I will need to figure out what size bump stops are on the fortunes and if I can get bigger ones that will limit my suspension travel up front, so I don't hit the tire on the rear of my wheel well at full lock.

[SicBastard]

Originally Posted by 95KA-Turbo

My only problem with running a larger rear sway bar is my exhaust is 4" under the bar and its been flattened out into an oval at that spot and it currently almost touches the stock S14 rear sway bar.

I am running the Sikky front sway bar which is a solid 32mm one (I have the old one, apparently the new one is hollow and like 30lbs lighter).



That bump stop graph is pretty interesting....so basically the smaller the bump stop the quicker you hit coil bind? I guess I will need to figure out what size bump stops are on the fortunes and if I can get bigger ones that will limit my suspension travel up front, so I don't hit the tire on the rear of my wheel well at full lock.

In the rear your car will run better with a rear sway if you can figure out some way to make it work. Where there's a will there's a way.

The new Sikky bar looks great! Finally a hollow option for the unobtanium 32mm Largus! And it comes with heim joint ends for $280. Sweet!

Older style bump stops were made out of very hard rubber or even hard urethane. But at FatCat and Ground Control the bumpstops are made out of a newrer material called MCU, multi-cell polyurethane.

Ground Control - Foam bump stop ($12.00ea)

As usual the off road guys are paving the road to the future of suspension design. Nitrogen Bumpstops

Nitrogen Bump Stops

http://www.offroad-engineering.com/f...ump-stops.html ($185.00 ea)

[SicBastard]

HioSSilver over on LS1tech has been running a 4th gen camaro with a multi-plate racing clutch + crate ls6 and doing 11.53 @ 122 1.90 60' (on 18's) with only 413 rwhp & 395 rwtq!! You'll notice his 60' is nothing special, I've seen plenty of Nissans do 1.60 60'. I think part of the explination for his awesome et per hp is due to the clutch's low MOI (moment of inertia).

Here's a pic of his Tilton 5.5" triple racing clutch bolted to a button plate that is sandwiched between a stock auto flexplate and the clutch.



I sent him a PM

"Been doing a bit more research on racing clutches in street cars, and was wondering if your 5.5 is still alive?"

"Yes it is. The first set of clutches (new) lasted 2.5 yrs. The next set lasted 1.5 yrs (used) and the set in it now is used 6mths. This is my dd. I really like this set-up. It cures all that clutch bullshit evryone goes through."

In a thread he posted about it he said his GF can even drive it!

And a pic of a Zoom flywheel for an LS1 (left) next to a stock iron LS1 flywheel (right), (they are the same size, both with 153 teeth for starter engagement). The zoom flywheel can accomidate upto a full 12" clutch disc



Here's a list of the MOI of different clutches

Tilton Clutch Assemblies MOI (lb-in^2)
Includes: Clutch cover with diaphragm spring, pressure plates and floater plate(s)
(add 66 MOI and 2.5# to include the button
(add 87 MOI and 3.4# to include a Sonic ultra-lightweight flexplate)

13 4.4” Tilton carbon carbon 4 disc
21.4 5.5” Tilton 1 disc cerametallic
29.4 5.5” Tilton 2 disc sintered metallic (6#)
32.2 5.5” Tilton 2 disc cerametallic
52.4 7.25” Tilton 1 disc cerametallic
76.3 7.25” Tilton 2 disc cerametallic
89.6 7.25” Tilton 3 disc sintered metallic (10.2#)
99 8.5” Tilton 1 disc cerametallic
100.2 7.25” Tilton 3 disc cerametallic
158 8.5” Tilton 2 disc cerametallic
337 9.0” Mantic street dual sprung clutch (33.8#) cool set up!
>3200 11.5"? Stock LS2 flywheel and clutch (52#)

A good rule of thumb with racing clutches is that doubling a clutches weight will double its MOI, but doubling its diameter increase the MOI 4 times! Another rule of thumb is that increasing the clutches diameter 1.1" doubles the MOI.P

Here's PTTs set up. I was all excited because they were one of the first to introduce organic discs in race car, multi-plate sizes. But I spoke to their rep today who informed me that they don't reccomend their organic discs on any car over 400 hp regardless of how many discs. Bums me out, but maybe I'll call and talk to one of their engineers.

the "button" looks bigger in the pic than it actually is. It's inner 6 bolt holes line up with the flexplate's (flywheel for an automatic car)inner 6 bolt holes .



KH3049 goes for $812 + $263 for there small diameter through out bearing = $1075

[SicBastard]

Had a nice little trip last week!



At first I was considering getting a 32 gallon, cause some day I'd like to go E85 which suck a TON of fuel. But I was worried about being able to get it out from the top of trunk. ATL makes a "shoebox" style container that has no flanges, so it's easier to drop from the bottom. Turns out the 32 doesn't come with a shoe box lid. The 32 was going to be pretty damn tall (would have almost hit he trunk torsion springs) anyways. The aluminum containers are supposed to only weigh 15 lbs compared to about 25 lbs for the steel.

So I got the 22B!


The 22B even fits from the top with no problem. So the shoe box lid wasn't needed.


The Nascar surplus ATL lid I scored on ebay came with a huge 1.5" vent tube, which is absolutely unneccesary unless you plan on doing speed fueling refills. Otherwise a vent as small as AN-6 with a check ball (for roll-over) will sufice.

I read on more than one forum that fuel cells with very large vents can evaporate enough fuel to empty a small tank over a few months. The guys at ATL thought that was bull-shit. Either way I was reading up on fuel vents. The stock system routes a small hose (probably ~3/8") to the charcoal canister mounted just infront of the passenger side rear bumper. The idea is that all of the fuel fumes get trapped there while the car is not running. A second (equally small) hose connects the other side of the charcoal cannister to the intake manifold. When the car is started, all of the stored fuel vapor is sucked into the combustion chamber via running vacuum. The charcoal canister weighs almost nothing, and is supposed to last the life of the vehicle. I am considerng installing a -6 check valve back to the original charcoal canister. And placing a fuel level sender where the 1.5" vent is.

The orignal ATL fuel level sender is non-mechanical. It is called a capasitive sender. They can be made almost any length, and can be set u for any resistive range to match different stock gauges. However, they have to be calibrated to one specific fuel type. A gauge set up for gasoline, will not read correctly once you pour in E85. ATL's newer gauge type is about $40 more expansive, is mechanical, has a set ohm range, and reads accurately regardless of fuel type. The fuel level senders are about the same diameter flange as my 1.5" nascar vent but the level senders have a 5 bolt pattern compared to the vents 8 bolt.


Above is an example of a capacitance type level sender. it measures the resistance between the center probe and outer tube.

[gsracer]

longest running thread im still subscribed to. I simultaneously want you to finish it and not to, because it never fails to disapoint with great tech info and awesomness.

+1 for you.

[SicBastard]

Thanks a million! I want to finish it REAL bad, but there's still about 8 grand I need for all the loose ends. Plus I just moved to NYC for a year. So there will plenty more time before it's on the road. I can't wait to start dialing in the suspension.

Got my hands on Engine Analyzer Pro software. Seriously cool program. I have a top of the line i7 processor and 6 gigs of ram, and the computations can still take upto a minute every time I try and get it to run a combo! Crazy. I've been playing with options on my 404 with LS3 heads. Originally, after a lot of research I settled on a 238/244 cam. After playing wiht the new software that may change a bit. Here's some interesting things I learned while playing with the software:

1) don't need more than .604 exhaust lift
2) I'm not willing to loose >60 ft lbs of torque below 4000 rpm with a tunnel ram intake even if it gains me 50 hp up top.
3) decreasing intake duration from 238->232 lowers avg hp 1
4) increasing intake duration from 238->244 lowers avg trq 2
5) the only change w a big 90mmX1" spacer is a loss of 1 hp!

One thing that I was really interested in was exhaust valve duration. The LS3 heads are very unique in the world of modern performance heads in that the exhaust only flow 66.5% of what the intakes flow. This is considered pretty low. Unless you're talking about a modern Winston cup car. All of Comp cams off-the-shelf LS3 cams try to "overcome" the relatively poor exhaust flow by running a huge 15 degrees more duration on the exhuast lobe than the intake lobes. Normally this would be considered excessive on onything short of a full blown nitrous motor. And really didn't make sense to me.

My intake duration 238 + 15 = 253

I did multiple tests on the simulator. I would always add the extra duration to the exhaust opening in my tests, so not to change the overlap. And with comps 15 degree split I would loose between 5 and 15 ft lbs below 5000 rpm. In one simulation I lost 50 ft lbs at 3500 rpm with the greater exhaust duration! And I usually only gained 5-7 hp over 6000 rpm.

Then I thought maybe even my split was too much. My proposed 238-244= 6 degrees of split. Dropping down to only 3 degrees of split with a 241 exhaust duration picked up a huge 13 ft lbs at 3500 rpm and only gave up 1-2 hp above 5500 rpm.

Here's the Winner cam as of right now.
238/240 112 +1 .612 lift in and ex
max trq 570 @5000, 479 avg 2500-7000 rpm
max hp 600 @6000, 436 avg 2500-7000 rpm

Every one warned me not to get my hopes up over 6300 rpm with the stock intake. And boy the Engine Analyzer doesn't disagree! This thing just falls on its FACE over 6500 rpm. But with an AVERAGE of 480 ft-lbs!!! everywhere, my heart's not exactly broken up about it.

Here's an example dyno plot produced by the program. These would be engine dyno numbers with a 300 rpm/sec accel rate, and with all accessories and a flywheel. Here the cam is retarded to -1 (+4 has almost become the standard in the LS world)! It trades 4 ft lbs down low for 5 hp up top compared to my +1 cam (that is 2 degrees more advanced).

[SicBastard]

Got a little work done on the rear subframe yesterday. I noticed that even without an upper bushing in the front frame attachment points, that the subframe was contacting the car frame on the lip around the tube/cup that used to house the stock bushings (where everyone puts the collars). I still want to raise the rear roll center a bit, so raising the front of the subframe with no upper bushing makes sense. But raising the whole subframe up for a little free roll center correction is a massive bonus. The cup lip sits about 6mm higher than the rest of the subframe.

The stock subframe bushings sit about 10mm higher than the cups in the rear and about 15mm higher in front. I've reduced that to about 2 mm in the rear and -6 in the front now for a total roll center correction of ~15mm (-8mmR and -21mmF)!. That's like installing drop knuckles! Even if it is less than an inch.

Drop knuckles...$1100
Dead Grinding wheel... $3

Stock S13 bushing

My front S14 subframe less stock bushing but pre hackery. Notice the ~6mm step to the top of the cup even without a bushing.



Post Grinding. I'll probably throw a bead in there to make up for what I took off.

[Motary]

Very interesting topic so far!
Here are a few pictures of a subframe that was raised 55mm:







Link to blog

[SicBastard]

That's pretty crazy. The unequal A-arms in the rear give some very forgiving camber curves. So with the inch of correction I'm already getting and going without a crazy slammed ride height I should be all good. I don't think that's necessary unless you're running around with a ride height of less than 3 inches.

[GSXRJJordan]

Just read your engine analyzer post, very interesting finds! What did it ask about headers, just primary diameter and primary length?

[DamianN.]

You had me at hello. Your thread has so much useful info. I'd vote for sticky ;-)