mkd

iTrader: (8)

I got my car back from the tuner yesterday and am pretty disappointed. I was expecting easy low 300s, but am actually seeing 260 at 13-14 PSI. Apparently during tuning the air temp reached 96c (!!!).

Relevant mods...

Stock port, 30K miles
Stock twins
HKS DP
Bonez cat
Racing Beat dual tip
Autoexe intake
Efini y-pipe
RP baby SMIC <---- ~180in^2 compared to ~130in^2 stock, stock duct sealed off at original intake opening
Rewired RP pump
RP rail & 2200cc secondaries
HKS Twin Power
PFC

I feel like it's a real shame to have spent all this time and money on what I hoped would be a fast, reliable build, only to have a tiny IC bottleneck the timing map. For reference, at highway cruising speed on a 70-75F day the intake air temps sit right around 43-45C.

Some remedies I can think of...

1. Put in a bigger SMIC. I actually have a Knight Sports Super U I was planning to sell. The reason I didn't use it in the first place is because the duct it came with won't clear the radiator fans with the thicker Koyo radiator installed. Measuring the fans from the top of the engine bay they seem to be about 3.5"+ in height. Maybe a set of "slim" 2.5" fans is all that's needed to make the Super U fit. Another potential option would be the Greddy SMIC, but I've never been a fan of it for some reason. Maybe it's the "Greddy" branding or too many shiny tubes.

2. Use a v-mount. Seems like probably the best option these days (?) is the Pettit Cool Charge III. However it's awfully expensive all in (IC, elbow, new intake...), and I don' want to chop up a storage bin relocating the battery. And call me crazy, but I haven't had great experiences with Pettit's products... So I'm not exactly thrilled to throw any more money their way.

3. Use a FMIC. This just seems like a big pain in the *** for lots of reasons. I also don't personally care for the look.

4. Water/meth injection. This is starting to look really attractive. What should I expect to see for temperature reduction? Are we talking 10 degrees or 30 degrees? How often does the reservoir have to get filled up? (I think the 2-gallon OE-type Sake Bomb rear hatch reservoir looks great!). What governs when the injection is on or off? What are some downsides to water/meth injection other than price and having to fill the thing up?

alexdimen

iTrader: (13)

Sounds like not enough IC plus not enough air flow over the IC.
Do you have a duct extension down into the bumper opening? That will make up some for the small size with more air mass. You also need to seal the duct from the battery and ac dryer as well.
Did they give the car a break between runs? There's virtually no air flow on a dyno compared to road tuning. I don't care what kind of fan you put on it. They should have backed off well before 96C.
That's just a stupid high AIT and I would also expect it to affect power just due to reduced air density. You're putting 20% less air and fuel in the engine at 100c than you would at 20c.
And for God's sake, just use that super u! You already have it...

mikejokich

iTrader: (1)

I have the Australian version U-type SMIC with a Fluidyne radiator, which is slightly thinner than the Koyo, and it fits fine with some modifications of the radiator and fan shroud. If you do these two things, you should clear the IC and ducts even with your Koyo radiator. First, the upper radiator mounts are typically fastened with the stock rubber stand-off bolts. Get rid of these and rebolt it with a standard short bolt directly to the frame with a thin rubber spacer to prevent galling and your radiator will move about 1" lower. Unbolt the radiator and prop it up as high as you can to get to the stock rubber bolts. Of course, you have to remove all the stock overlying parts (IC, battery, air intake, etc.) first. Next, take off the fan shroud. There is about 1-2" of extra height on the shroud that sits on the radiator. My Fluidyne has aluminum posts where the shroud fastens on top. I drilled out the plastic on the shroud to allow the shroud to sit lower by going over the post instead of on it. Replace the shroud with a bolt and large washer and using a piece of rubber hose slightly taller than the post as a spacer on the post to tightly secure the shroud. Also, I did have extra space on the lip of the shroud that touches the radiator. I shaved it down with a small Dremel tool all the way completely around the shroud. You gain about another 1-2" doing these things with the shroud. If you still need a little more lowering, you can bend the lower radiator fan brackets down a little to gain a little bit more space. I just needed to do the first two things and I still have room to spare.
Mike

cr-rex

iTrader: (114)

V mount the radiator and unlock all your hidden power.... it's the only mod you need to do to fix all of the everything that has you upset.

Sgtblue

iTrader: (16)

Results with AI depend on many things, nozzle sizing, nozzle location, management, it’s methanol content (if any), IAT sensor location etc. Personally with your mods I don’t think you should tune with it. It should only augment once IATs are acceptable.

Pete_89T2

iTrader: (4)

OP - Since the car was being tuned on a dyno, there's another possible explanation for the high IATs that no one else has mentioned thus far that has nothing to do with your car's inter cooler setup. HEAT SOAK - Whatever IC setup you have will work best when the car is in MOTION. While running stationary on a dyno with nothing more than maybe a big fan blowing air in the general direction of the car's nose, and having the hood open while doing the tuning will cause everything to heat soak. The more pulls you have to repeat, the worse the heat soak gets.

The tuner/dyno operator could mitigate the heat soak problem by giving the car lots of time to cool down between pulls, and by misting the IC core with some water from a hose between pulls. Did he do this?

DaleClark

iTrader: (55)

Is your boost pattern solid?

What plugs are you running?

I think the high temps are where to start for sure. Good IC ducting makes a HUGE difference in a stock mount.

Going with a larger setup (V-mount, FMIC, etc.) can drop temps but it's a lot of fab work for sure.

Water injection is a great way to go. I'd just get a simple AEM setup and put a nozzle in the TB elbow. Drops temps like a rock while on boost. I have mine plumbed into the windshield washer tank to use the fluid from that tank, saves having to have a separate tank.

Dale

Sgtblue

iTrader: (16)

^AI is absolutely worthwhile. But I still would get those IATs under better control and not tune with it.

fwiw—-> https://www.rx7club.com/auxiliary-in...ion-fd-959565/

alexdimen

iTrader: (13)

Yep, no one had mentioned that yet...

Just playing. Seriously though, I completely agree with you - it sounds like the tuner was ignorant or being lazy.

Even with a stock IC that should never have happened.

Personally I wouldn't let someone work on my car again if they knowingly allowed my AIT to get to almost 100C. That's part of tuning. You don't just slam the accelerator down over and over again until something breaks. You watch closely for signs of trouble. It's why we have sensors and logs.

Pete_89T2

iTrader: (4)

Doh! That's what happens when I skim thru the posts too quickly!

^This. My take is the OP needs another dyno session with a more competent tuner before even thinking about redesigning his intake/IC setup. Find out if he really has an IAT problem first, quantify it and make decisions from that information.

mkd

iTrader: (8)

No -- but I've done some research and will modify the duct that comes with the Knight Sports IC if it looks like it needs to be extended further down into the bumper opening.

Almost certainly not. See below...

Again, almost certainly not... See below...

Appreciate the info! I'll give that a shot. Unfortunately working on this car is always a logistical challenge as where I live I have no space to work on it, which means trucking parts and tools 200 miles back home, and then working on the car over short periods of time, like weekends.

Silly me, I just realized the Pettit CC III isn't even a v-mount. I doubt I will do it any time soon, but other than Greddy who makes a v-mount kit? Is the radiator that comes with the Greddy known to be good? (Using a Koyo N-FLO now and very happy with it).

Boost pattern looks good. Plugs are brand new NGK 9/9.

The main concern I have with water/meth injection is that I 100% do not want to have to refill the reservoir in-between re-filling the fuel tank. Second concern is a clogged nozzle or broken pump going unnoticed until boom.

I will definitely not be going back to this mechanic, at least for tuning. It was a strange situation. I heard very good things about him () so I drove my car 400 miles down to him in SoCal. I had planned on staying around his location for a couple days while he tuned (he usually takes two days to tune -- likes to let the vehicle cool overnight between sessions.) Long story short, I ended up having him do the LIM gasket while the vehicle was there, so went home and came back two weeks later. Big, expensive, pain in the ***.

Before I headed back to him, he called to let me know the LIM was done and that he was going to start tuning over the next two days. I asked him to kindly save me a printout at 13 PSI, to which he informed me the power sensor on his dyno was broken. Nice. Could have told me that before 400 miles of driving and a plane ticket. He said if I emailed him a dyno quote from another shop he would discount that from the tuning price. What ended up happening is that I arranged for him to use the dyno at the nearby rotary shop DNA Garage. So he did one tuning session on his dyno, then took my car to DNA Garage, presumable for 1hr of dyno time (on his dime), and then I came down and picked it up.

So on the one hand, he should have had it pretty well dialed in after the first session on his dyno... but on the other hand he was probably rushed using another shop's dyno at $75/hr... Still doesn't quite add up to me. Another annoyance is that I had the PIM voltage up about 10% across the board when I dropped the car off, just to be safe, which I told him, and after picking up the car and driving halfway home I realized that he never reset the PIM voltage before tuning.

However you cut it, I'm pretty annoyed at the situation, and like I said will not be taking my car back to him for tuning at the very least.

I plan to put the Super U in, make sure the ducting looks legit (seal the top and extend the inlet if needed) and take it to another shop in my area for another tune. Am I nuts for expecting 325-350rwhp with my setup??

gracer7-rx7

iTrader: (16)

Sakebomb Garage does tuning in Fremont. Suggest you make an easy trip over the hill and through the valley to Fremont and have the tune checked out to be safe.
Your results seem rather low and it sounds like you went through a bit of a **** show.

That's about normal for a SMIC. You wont' see ambient from a Vmount fyi but it may be a little cooler.

1. Is a good simple option. Pettit, Greddy, PFS, M2 are all good options
2. V-mount defintely provides the best cooling options all around but harder to switch back to stock for smog and a/c is difficult to route.
3. No. Don't.
4. Water injection is not reliable. Use it to add a buffer to an already tuned, well working car. Not as a band aid to attempt to address a problem.

Let me know if you decide to go vmount. I may have a proposition for you to make it cheaper.

mkd

iTrader: (8)

My plan is to take it to them for another tune after installing the Super U.

It's been a while since I owned a modified car, but from what I remember 10-15 years ago, a lot of shops will overlook visual modifications as long as the sniffer passes. Has that not been your experience in recent years in the Bay Area?

Like I said I am inclined to just install the Knight Sports Super U SMIC I already have and cross my fingers, but if you have a tantalizing proposition on a v-mount shoot me a PM

I'm also curious if adding an puller fan to the back of the Super U would help to prevent heat soak at idle, or if it will just get in the way of airflow while moving.

gracer7-rx7

iTrader: (16)

1. No. Most shops that I've gone to do not overlook visual mods
2. Yes, that can help. Especially at slow speed stop n go.

mikejokich

iTrader: (1)

I added two smaller Spal puller fans to the back side of the my U-type IC. These are around 300cfm each. It definitely helps when in traffic and on city streets with a lot of lights. I did have to trim the Spal fan shrouds slightly and the IC air box some to make enough room to fit between the pulley and belts and the IC.
Mike

cr-rex

iTrader: (114)

you dont need a kit. the cxracing/rotary works radiator is more than sufficient. mounting it is very basic and running the hoses is basic as well. the whole install is just basic lol. get that radiator, install it and all the air temp issues youre having will go away

mkd

iTrader: (8)

Do you happen to recall what model fans you're using? I see they have a 4.3 x 4.3 x 2.4" fan @ 147 CFM, and a 5.5 x 5.5 x 2.4" @ 342 CFM. Did you just wire them on full-blast all the time, or did you do something like wiring them into the coolant fans? Are they louder than engine idle noise? How long have they lasted so far?

mikejokich

iTrader: (1)

My under hood with the Australian SMIC and the Autoexec.

mikejokich

iTrader: (1)

They are the smaller of the two, so they are 300 cfm total rather than individual. I wired them to my center console. I bought another fog light switch, added it to the dummy switch location in the center of the three switches. I have two speeds, one directly to the ignition for full on when hot and in traffic(which is rather noisy when stopped) and the other position has a power resistor on it before going to the ignition and is about 40-50% power and is very tolerable and just a low hum.
Mike

mkd

iTrader: (8)

Aww yes, I've seen this engine bay before.


I think you said you ceramic coated the IC end caps and the core?

arghx

iTrader: (3)

It's likely that the car did not have large enough or well positioned enough fans on the dyno. Also, you need to let it cool down between runs.

mkd

iTrader: (8)

I'm definitely considering using those fans. I'd like to wire it in a dual-mode sort of way:

1. Low-speed, always-on through a resistor
2. Full-speed, activated by a thermal switch in the intake elbow. This switch looks like it would work well: https://www.omega.com/en-us/process-...TT-F3A-140R-WL

Wiring seems like it would be straight forward and reliable. I'm curious, though, what solution did you come up with for actually physically mounting the fans to the IC?

mikejokich

iTrader: (1)

I usually leave it on the resistor limited setting. The resistor is a larger heat dissipating power resistor. I can check on the ohm rating and get back to you. It is again about 40-50% speed. To control it by heat, you have to have a PWM fan controller using a temperature sensor input and a water proof PWM DC fan. I have both for my Autoexe air intake in order to ram cool ambient air into the intake at low speeds and in traffic. I have a 500cfm PWM DC waterproof fan in the Autoexe that is controlled by a Lingenfelter PWM fan controller used in aftermarket Vettes. The temp sensor I use is the same fast acting Triumph sensor many of us use in our AIT location in the UIM. I can set the fan speed to vary between any on temperature and to ramp up to full depending on my high setting. It works perfectly. You can see the controller to the far left in my under hood picture. It is the small black box near the coolant filler. The reason the ram air works for me is that I have an aftermarket Abflug bumper with a large rectangular scoop molded into the bumper that directly leads into the Autoexe. True ram air like the old GTO's or other American muscle cars. My AIT's at full boost actually go down as the car accelerates, not up. The ram air, U-type cooler, and the ceramic coatings are all working together. If I start WOT at 35C at 20 mph, by the time I reach 120-130mph my AIT is 32 or 33C. This is again I stress a SMIC, not a V-mount. This is how a well designed heat management system can work if you have the time, money, and a good well thought out plan without the need to go to a V-mount.
Mike

mikejokich

iTrader: (1)

To mount the fans, use the metal fan mounting pins you can buy on line. Don't use the supplied cheap plastic mounts. Also, I used JB Weld on the metal connecting clips to make sure they stayed put and didn't dislodge into my pulleys and belts.
Mike

mkd

iTrader: (8)

Please do check on the Ohn rating! I had planned to get a small assortment of large 100W guys.

That sounds like a killer setup. I wouldn't mind doing something similar to what you're doing with the PWM intake but for the IC -- I think the challenge would be in finding PWM fans of appropriate size for the IC. What a had in mind was quite a bit simpler, just switch from the low-lower resistor circuit to a full closed, no resistor circuit using a thermal SWITCH at a set temp. It literally just clicks on and closes its circuit when it reaches a certain temperature.

Hmmmm got an example of these pins? I have no idea what you're talking about!