3.5mph: J-Rho's SM Build

[dorimaster]

Ill give you a few critiques to all this a$$ kissing...

The vq40 and 35 have more tq than all other engines you listed, you went the easy route, didnt want to spend the time, dont have the skills to do it. What you said is completely wrong! Many others with these will chime in, i am putting one in my ae86.

I have used water to air intercoolers for years in different cars and you NEED the small heat exhanger! You will boil that water pretty quickly, with just a session! It ONLY works for drag racers who make quick passes then put in more ice. I ALSO run a cell for EXTRA cooling, but nothing like the air can cool it down fast enough, put on temp gauges before and after to see. You aren not the 1st person to try this.

Also the clear hoses you are trying to run will laughably melt within a few laps and destroy your engine. Nothing clear has the temp ratings to last on a water-to-air(keep them in your pool), check with the manfacturer/box they came from. There are SOOO many types of hoses u can use, just not clear. To name a few are.. the easy choice: silicone, trans-cooler lines, oil-line, fuel line..even normal reinforced rad hose. Just not home use low temp clear! This is not cheap either, about $15 a foot.

Your wheels although they are blingy are by no means very light(or cheap), the offsets as mentioned are wrong, and with the widths of tires you chose are larger than optimal, they are just too large for a small light weight car like ours to effectively heat up and utilize on the track. There is a "sweet temp" for all tires and you will BARELY get close to it. PLUS most rules dont allow for tires being more than .5" past the STOCK body lines.

You have LOTS of weight to lose..tar insulation, stock wiring, paneling, pasenger-seat!? In racing you make your car lighter than the rules allow, then add ballast to put that weight where you want in(low centered)

just opened a fresh bottle of haterade!
Pete

PS your car is nicer than most hope to dream and you are a better driver than most wish to be

[J_Rho]

Hi Pete,
I don't think I can comprise a good response without helping you to first understand the difference between autocross (what I do), and track, or road-race, type events (what I think you think I do).

Look to see if any "Solo2" events are happening in your area, and go check them out. I think you'll find these two types of events, and what works best in each, quite different. Also, check out the this link:
http://www.scca.com/_FileLibrary/File/2007SoloRules.pdf
which I also posted in my first post, to the SCCA's rulebook. Skip to chapter 16, which contains the rules for the class I'll be racing in, Street Modified, and keep in mind that with the SCCA's rulebook, "if it doesn't say you can, you can't".

You may have some more good comments after having done this, but in the meantime, if you don't mind, I'll be consuming your suggestions with a rather large grain of salt.

[Broaner]

Seriously harsh man. I had some differing ideas on the build but I like to give credit where its due.

I do agree that the motor choice is a bit off. I think a VQ would be supreme but I'm biased and didn't want to jack the thread.

I think you have a semi-valid idea about the heat exchanger. But again, way too harsh. If I were a mod I've give you sharp kick in the @ss.

[J_Rho]

I may have been a bit biased in my path as well - my middle name is Garrett after all...

(really, it is)

Show me a NA VQ 4 liters or less that I can build for <$10k that makes >300ft-lbs over a 4000rpm range, and I will seriously consider it for phase 2. I may be biased, but I'm not that biased.

If 20+ pounds of ice (what this holds) isn't enough to keep 400whp cool for 5-10 seconds of full throttle and 2-3 minutes of part throttle, I can either get a bigger cooler, or just put fresh ice in between runs.

[g81981]

Awesome thread. Best of luck with your build and race.

[vw_nissan]

Originally Posted by dorimaster

Ill give you a few critiques to all this a$$ kissing...

By saying this and all of your unnecessary over aggressive criticism, you have just become d***k head of the day. Obviously, deep inside you, you are thinking why all these people admire this guy
(kiss a$$ in your own head ) so much but not me (note: I am dorimaster!! )

The fact is that you don't even know wtf he is building his car for (if you even cared to read his previous built thread or read the first post in this thread in its entirety, maybe you would have known.) Instead, you went ahead calling people kiss a$$ and how he doesn't know sh*t about engine built.

Maybe you are right about his decision on the engine choice, but your attitude is just wrong. I am sure the original thread starter WOULD have appreciated your suggestions or opinions if your ego is not bigger than your d**k head.

The forum is for people to exchange knowledge and idea. Having people like you just driving the bus over everyone isn't helping. And if you are so confident about your knowledge, then build an autox worthy car to compete with him in the National this year. Maybe that will win you the bragging rights, but still not it does not win you the disgusting attitude.

Jason, I am sorry, I just have to rant because his comment may have offended everyone in this thread.

[Broaner]

Originally Posted by J_Rho

Show me a NA VQ 4 liters or less that I can build for <$10k that makes >300ft-lbs over a 4000rpm range, and I will seriously consider it for phase 2. I may be biased, but I'm not that biased.

I didn't know if motor swaps were legal in your class so I didn't go in depth before.
http://**********************/forum/showthread.php?t=224931
and
http://**********************/forum/showthread.php?t=239093
Sadly there are not yet any dynos for any of these options. I'd go with the 90mm stroke for ultimate torque. This puts you just under the 4.0 liter limit. The stock 35 puts down a super flat ~230Wtq sometimes peaking to 240tq. In theory the displacement bump alone would move you to 255lb/ft. I'm sure with good tuning and supporting airflow mods the 3.91L with stock heads would make at least 270lb/ft. With a step in the heads I think you could get to or very near 300lbs. And thats all excluding a bump in compression. If you went to something reasonable like 12:1 I see no reason that serious 300+ torque numbers could be laid. If you went with 13:1; good night!

The VQ weighs exactly what a KA does. http://www.engineswaptech.com/forums/thread/1186.aspx But without the turbo equipment there can be reduced weight and significantly less complications that could occur on race day. Finally, the VQ can sit further back in the chassis.

The only problem I forsee for you if you did go this route would be the tranny. The Z33 6MT produces very short gearing when combined with the stock final drive of the S13. On stock OD tires 1st brings you to <20MPH. Second will not get you past 50mph. That puts a shift right in the middle of the speeds you said you'd normally be going. I run a 25.5" OD rear tire and its still super short with a J30 3.92 diff. Even with a move to 26" OD on the tire I still think the rear end would need to be degeared to somewhere around 3.5:1(Not in the mood for doing math).

[J_Rho]

I can use any motor as long as it uses a Datsun/Nissan/Infiniti block - that's basically the only restriction - could even use some made-from-scratch CNC heads if wanted.

Part of what made the VQ less attractive was the unprovenness of the motor, at least in a high-zoot NA setting. When I saw the dyno of the KA24 with the AMS GT32 setup that really helped seal the deal - I figured with some better supporting mods, a higher-tech turbo, etc., I could exceed those results in both the lower and upper end of the RPM range-

Just imagine this, but with the torque coming in earlier and hanging around a lot later. 300-ish from low 3xxx to low 7xxx is all that's really needed - the plateau being up around 350 (will be higher with C16) is some nice gravy.

I think with enough work and $ the VQ wold be able to match this, but it's going to be tough to get a cam/valvetrain setup that will produce the torque up top (6k+) and at the lower end of the rpm range (<4k). Maybe with all the latest VVT tricks and whatnot. If it could rev reliably to 8k, then we could work more in the 4-8k range too. The gearing isn't too large a concern, if need be, could go to a really short rearend (4.77 or so) and run always in second and third gears instead of first and second. Some of the 6-speed Miatas do this effectively.

Like Cuba Gooding said, show me the mon, errr........ dyno!

[steve shadows]

you mean the dynapack

[NickBW]

Great work. It will be interesting to see how this thing goes.

I wish there were more people like you campaining ae86's for me to take notes from.

[J_Rho]

Originally Posted by steve shadows

you mean the dynapack

Those will work too... When I come back from the dyno (dynapack), if the car is a turd, I promise you first place in line for the IToldYaSo.

[FreeThinker]

Originally Posted by dorimaster

Ill give you a few... blah blah blah blah......

Um , next time actualy RTFP and you wont end up being twat of the day.

Also I dont think you should be climbing up on your pedestal and preaching basics or right/wrong to an accomplished builder and racer....

[FreeThinker]

BTW Jason, im curious what you meant about the binding in the rear suspension with the spherical upper control arm.

From what I can determine the two uper links basically form one effective pivot point slightly outboard of the actual point where they connect to the upright.

Basically creating an imaginary kingpin axis with an upper point further outboard. Then of course there's the toe link.

No?

Also you mention the lower control arm being a source of bind... are you just referring to them having bushing inners?

Oh and I think you made the right choice of motors unless you had tons to spend on a VQ40. Or maybe a VQ25DET would be a good option later on with the displacement/ system.

[J_Rho]

In the rear, the lower control arm has a variable amount of stiction (a word used in suspension circles to describe the amount of force it takes to start something moving from a "stuck" position) based on how tightly the inner pivot point bolts are tightened. Once the arm is in motion, the bushings presents a further damping element would be better left handled by the shocks.

The uppers do form a "virtual" ball joint if you draw a line to intersect the paths of the two arms. This works fine when both the arms are working at angles near parallel. However, as the car starts to get really now, the arms start to work at angles where the trigonometry wreaks havoc on the differing lengths of the two arms. Once you know where the suspension is going to be, you can better set their lengths for that working range.

[steve shadows]

Originally Posted by J_Rho

Those will work too... When I come back from the dyno (dynapack), if the car is a turd, I promise you first place in line for the IToldYaSo.

Im just bustin you Jason Im sure it will be a torque monster. good luck

[Full_Race_Geoff]

ill ass kiss a little... i love your car.

[steve shadows]

enjoy the nectar and sweet juice that is ass kissing ....

FA style

[rs4race]

I cant wait to see this finished.

[J_Rho]

Originally Posted by rs4race

I cant wait to see this finished.

You're not the only one!

Exhaust parts are getting their thermal coating and won't be back for a few weeks. Lots to do in the meantime - vacuum system, breater system, all the new wiring, mount passenger seat.

Gotta get hacking away on the fenders, do the flares, and decide whether or not I want to paint the car...


Trying to be ready for some events in mid/late March here in So Cal (SD Tour and Fontana ProSolo).

[GlacierFreeze]

Those tires.... mmmm meaty! haha
How much camber are you going to be running?

Dang you and your teaser shots!

[J_Rho]

Originally Posted by GlacierFreeze

Those tires.... mmmm meaty! haha
How much camber are you going to be running?

Dunno yet, I'll start with my STS settings and go from there. Probably still 4+ in the front, between 2 and 3 in the rear.

[AceInHole]

Originally Posted by J_Rho

Dunno yet, I'll start with my STS settings and go from there. Probably still 4+ in the front, between 2 and 3 in the rear.

I ran a couple events at the end of last year, but I think I bumped down to around 3.5 from 4.5 up front, running 285's on 18x10's (as opposed to the 275's on 17x9's). Not sure what sway you're using, but I'm pretty sure you're sprung higher than I am. I think my rear was still at 2.5, maybe down to 2.

I'm not sure if I'm mixing up my FS car but I recall running high 20's low 30's for pressure, as well.

Hope that helps. I'm busy getting ready myself, for the first tour of the season (GA - Feb 24-25).

[FreeThinker]

Hey Jason, I have some real deal Nissan N2 fender flares for the S13. PM me if youre interested.

[J_Rho]

I'll probably be leaving camber mostly alone initially, at least until I get some control over the roll centers and camber curves with some adjustable LCAs. Hoosiers tend to like a lot of camber, though I haven't run on them since the A3S03, so maybe that has changed somewhat.

Kumho is releasing a 305/30-18, so that opens up a 285/305 or the ginormous 305/345 as possible combinations of V710 to run.

Here is a mockup I made of the gauge and switch panel I'll be installing. It was designed using software from Front Panel Express, whose software will also estimate cost and provides a mechanism for ordering. I'll be changing 1-2 little details, then get it ordered in 3 or 4mm thick aluminum.


I'm sure some of you are thinking "with the gauges so far out of the way, how will he ever see them". My answer to is that during an autocross run, we don't ever have time to really look at gauges, except maybe the tach for the 1-2 shift. Unlike the track where you have time in the straightaways to look down and make sure everything is okay, an autocrosser's attention is elsewhere pretty much 100% of the time, so the gauges are more for monitoring things between runs. I'll be datalogging all the important variables anyway, so if something is happening with the motor during a run, if it doesn't blow up right then and there, I'll be able to see what was going on later in looking at the data.

[rs4race]

sweet. I love the gauges and switches.

Those tires are huge, I cant wait to see those fender flares on their either.

I love the progress pictures.

[Broaner]

Did you mention what EMS you're running? Anti-lag should be awesome when combined with the twin-scroll. I didn't realize you'd be running it. Forget all my ideas of the VQ. An anti-lag system will be incredibly reponsive.

[Punch]

Where's your radio?

[J_Rho]

The EMS is the AEM piece. Its anti-lag capabilities are not the most sophistiated, but should be adequate for my purposes.

Punch, here's my radio:

O. Radio/Stereo equipment and/or its component parts, including
wiring, antennas, amplifiers, speakers and their enclosures, etc.
may be added, replaced, or removed provided the part added,
removed or replaced serves no other purpose. Any visible holes
that result from the removal of equipment must be covered with a
cover of unrestricted material. Covers may be used to mount
gauges, switches, etc.

[AceInHole]

O. Radio/Stereo equipment and/or its component parts, including
wiring, antennas, amplifiers, speakers and their enclosures, etc.
may be added, replaced, or removed provided the part added, removed or replaced serves no other purpose. Any visible holes that result from the removal of equipment must be covered with a cover of unrestricted material. Covers may be used to mount gauges, switches, etc.

-Fixed :P

[J_Rho]

True story-
At nats last year, I was one of the few cars in the class with a radio, as it was an option on the Civics, most didn't have it. So I've got it on loud, to try to listen to my competitors' times over the noise of other cars.

I take off for my first run, and in the first half of the run, *think* I hit a cone but am not sure - as I'm in the braking zone coming towards the final stretch, I hear the announcer say out of nowhere (not realizing the radio is still on) "Ohhhh, and Jason hit a cone!!!" - I'll tell ya, that one's a real mother #^$@*%$er to your concentration.

[wperdigon]

man what an amazing post, but why didn't you consider the qr as an option? if built, it's just as strong as the ka with boost and its lighter

[PDM]

Good luck Jason, I await your results with the SM 240. (you know how much frustration I had last year with putting down power - but I never fully modeled the suspension enough to try to fix it.

Instead, I went the $$ route to fix my issues as time is such a resource I don't have as much nowadays.

I'm not abandoning the SM car...just giving it a rest to watch you chase Bob and Vic this year.

(as you know, I'm re-surrecting my tube frame 510 for E Prepared and hope to chase down a podium in 2008 at Kansas in that car - plus I'm getting smart and getting a tire-warmer errr, partner to race with now)

I'm curious if air to water is the route to go.... as I never really saw high intake temps in my car Jason... - and that was only making 345 ft/lbs at the rear wheels, but even with dual drivers I felt my i/c was too large for that kind of power. (remember I was only pushing 12 psi on my KA, so maybe my i/c is fine for 400-450 whp at 18-20 psi.

When I spoke to Andy at Specialty in depth with my thoughts for water to air, he didn't feel it would benefit enough as water is not light...... Drag racing maybe, but for our stuff, he felt it may add just as much weight and a lot more hassles.

Utimately, putting proper temp gauges before and after the i/c would likely diagnose if I ever did have a temp issue.... - but we found on grid at the National Tour, you had plenty of time with 2 drivers to water down the rad and intercooler and even put a fan up front with a small generator as insurance. I can just imagine the size of ice chest you'll have to tote back and forth from the pits in case you melt down your ice supply each run - let alone the hassle of grabbing bags of ice every morning.

I DO think that traction control is the ticket though in our high hp, RWD cars, as Vic and Bob both kill me out off the line and out of the corners. Speed-wise, I saw Ryan Carag run with Vic at the Pro straightline, and when I ran with Ryan, neither of us could pull a major lead..... - Whether AEM's system is adequate or whether you go with a stand-alone system, I firmly believe that it is a bonus if the class allows it.

If I bring the car back out, I'd definately move up to 18"s up front to get the shorter tire, as I'm running 275/40/17 V710's up front and that is limiting how much lower I can get my front down. But I had ordered the Kodiaks months before I really started thinking straight....



And yes, weight as you already know can be critical. My SM car was way too porky.....

Don

[J_Rho]

wperdigon, do you have any info of the QR motor successfully being run in a 240? It would be interesting, but keep in mind I'm not trying to re-invent the wheel here, just trying to make mine a little rounder...

Don, unless I've made some major miscalculations, my car will definitely be under 2600 pounds, and hopefully more like 258x, with the intercooler system full, which is ~120 lighter than Bob and about the same as Vic. The car will only be a set of brakes and a driveshaft away from being underweight.

I will find out pretty early on if I'll need to replenish the ice with only 3 runs and can plan accordingly from there forward. I already carry a 3 gallon sprayer, tire inflator/jump starter, helmet, drinks, and other various stuff to the grid spot, so a cooler with a 20lb. bag of ice isn't that much of an additional burden - heck, it'll help keep my drinks cold. I have designed the system to make it easy to dump out the warm water (can use to refill the sprayer!) to make room for fresh ice. Because I am not running an additional water/air radiator for the IC liquid, it cuts down on a lot of the hassles and weight on the nose. Of course, lack of IC fluid radiator relegates the car for use exclusively to autocross or drag situations. I can always get a larger capacity cooler to hold more ice if necessary, and will probably do that if other mods get the car under minimum weight - the weight of the cooler is in a nearly perfect spot.

The intercooler I chose is actually a little bit undersized for the target power level, as the next size up is too big. The goal was to keep the charge volume to an absolute minimum (along with anti-lag) to optimize response time. An air/air IC would require much more volume to cool as effectively as this ice water/air unit. In my analysis, I found that on an average autocross run, we go from being completely off the throttle to back on the throttle ~8 times per run. If I'm losing only 1/40th of a second (.025) each time due to waiting for the power to come in, that adds up to 2 tenths over the course of a run, and plenty of Champsionships are won or lost by less than that amount.

[AceInHole]

I've had an NPR intercooler (with custom end-tanks) on my car for quite some time, and honestly, combined with a smallish turbo (GT28RS) on the KA the boost response is very quick. I've actually asked Mark Daddio why he isn't using a water/air setup like he had on his SM neon (which was switched to air/air right after he sold it, actulaly). I forgot his exact response, but I believe our conversation resulted in: the car can already make more power than is useable for autocross, and a front mount is more than adequate.

[_Def_]

I'm a lil' drunk, but I did some off the cuff calcs.

Assuming 22 lbs(10 kg) of ice, that gives you approx. 3340 kJ of latent heat capacity with ice assuming you melt it all and the water is all uniformly 32 deg F.

Given an average power output of ~300 rwhp, or about 30 lb/min of average flow rate, you get about 13.6 kg/min of flow. Assuming post turbo IATs of about 180 deg F and dropping to 45 deg F, that gives you a drop of 75 deg C. Assume the autocross run is 1 min long for comparison.

Since Q = w * delta(T)

You're looking at about 612 kJ per run assuming no heat loss to the surroundings. With all the heat loss a system like this is likely to experience in a hot engine bay, I don't think 900-1000 kJ is too conservative. So you're probably looking at about 3 runs before you need to change ice on a not too hot day assuming you're carrying somewhere around 20-25 lbs in your cooler at a time.

Also looked at dry ice, but it doesn't look like it'd be worth the hassle of making sure it didn't freeze your heat transfer fluid, and the latent heat of sublimation isn't as high as the latent heat of fusion of ice for a given mass.


So yea, your ice/water IC should work just fine, especially if you can change the ice out after a few runs. On a really hot day you'll likely only get 2 runs out of it, especially if you're on the go pedal a lot on the course or it's longer than a minute.



Build looks good though, g'luck again Sias and Tunnel - their cars are definitely monsters!

[J_Rho]

Def, appreciate the calcs. The one part I'd change is the average power output - I think 300hp is quite optimistic, and even 200hp is probably too high. The Z06 I drove with similar power:weight hardly ever saw the bottom half of the throttle pedal's throw. Won't know exactly until I log the TPS.

PJ, the water/air isn't done as a way to increase the quantity of power, it is done as a way of improving how quickly it arrives. Keep in mind too, that Daddio's (or any) FWD car is very limited in its usable power in autocross. RWD and AWD especially have much higher ceilings of usable power, dependent on the surface grip.

[AceInHole]

Originally Posted by J_Rho

PJ, the water/air isn't done as a way to increase the quantity of power, it is done as a way of improving how quickly it arrives. Keep in mind too, that Daddio's (or any) FWD car is very limited in its usable power in autocross. RWD and AWD especially have much higher ceilings of usable power, dependent on the surface grip.

My comment was in reference to Daddio using a front mount air/air on his Evo. Even with his much higher limit of useable power, he's avoiding the complication of water/air, it seems. I recall him having to replenish the ice supply between every run on a hot day, as well.

On a secondary note: I just got my car back on the road, and with slightly lower comp (went to 8.5:1) the FMIC setup isn't noticeably bad on power response (haven't hit much boost yet, though).

[paemt]

Originally Posted by J_Rho

wperdigon, do you have any info of the QR motor successfully being run in a 240? It would be interesting, but keep in mind I'm not trying to re-invent the wheel here, just trying to make mine a little rounder...

To my knowledge, no, it hasn't been done. Will(wperdigon) and I discussed putting one in my 240. We concluded, it was doable, and likely about the same level of difficulty as the VQ swap. The Z33 trans can be bolted up to the QR, I think it requires a bellhousing from a QR Frontier manual trans. We never really got too involved in the swap, I decided if I was going to do a swap it was going to be a ATI Procharged VQ that I had access too. I am now selling the 240 so no swap.

[Jreyenga]

Great work Jason, it's always interesting to see others that are willing to push the envelope of what is possible within the rules. I have a wing question for you. What kind of theoretical Coefficient of Lift are you getting to? I'm in the middle of doing some 2D CFD work for a wing for a friend's SM2 car and a STS2 car. The best I can do is around -3.5 with a L/D ratio around 3.9. Just looking at the scale on your simulation you are pulling a lower peak vacuum at -900 pascals. Mine gets close to -800 pascals.

Unfortunately I slept through too many of my Aero classes so I'm not too sure about how to increase these numbers more. I've heard of F1 wings for Monaco having a Cl around -4. Without knowing what's a good maximum downforce number I'm not sure if I should keep mucking around with the simulation or just call it good enough.

If you don't want to share that information I'm ok with that. Good luck on the build.

[J_Rho]

I'm jealous of you guys that get to actually drive your cars. I drove my car 1100 miles the first day I bought it, and have only gone about 800 in the 18 months since... It's going to be at least 2-3 weeks before I get stuff back from the coaters, and now it looks like I'll have something that (if it goes well) will take all my time from next week through mid March. At least it's car stuff.

Jeremy,
My Cl numbers were quite a bit lower than yours, though I suspect a bit more realistic . -3.5 is close to 180 pounds at 50mph with 8 square feet, will be very impressive if you actually achieve that result.