HKS V-mount Instructions and First Impressions
 

Hey guys -

First off, attached is the scanned instructions for the HKS V-mount intercooler. I have not seen this document online somewhere and it's a Good Thing to have it somewhere for posterity.

So, some first impressions, notes, and thoughts on this intercooler kit.

My buddy Jon just bought this for his car, we are sloooowly building a rolling chassis back into a full, nice FD again. This is quite reasonably priced now, RHD Japan has it for just over $2000. It was around $200 for shipping, but that's hard to say because he got a few other parts from them as well. This is a heckuva good price for the quality of this kit.

The kit includes the intercooler itself, a bespoke throttle body elbow, piping, tons of nice brackets, and all the bolts and bits you need. The brackets are SUPER well made, very sturdy and quality.

The kit is designed to use a stock-style radiator, it doesn't come with its own radiator. There are pros and cons here, the BIG pro is if something happens to the radiator you can simply buy another new Koyo or whatever and install it. You're not out an exotic JDM-made bespoke radiator. The downside is the drain plug is in the wrong place and it's a little odd. It does have VERY nice formed metal pipes to run the coolant from the radiator to the engine. You trim your stock radiator hoses to join the metal pipes to the radiator and engine.

The kit has brackets that bolt the radiator fans to the *back side* of the radiator. The kit has a good range of thickness adjustment for these brackets so they will accommodate a stock radiator or a thick aftermarket one. On first whack the brackets fit a Koyo just fine.

The kit is designed to keep AC. Of course it's designed around the Nippondenso AC system, it has very nice brackets for the condenser to bolt up to. It does include new hard lines to accommodate for the move of the condenser, however they DO NOT seem to work with US parts at first whack. I have a spare Nippondenso drier and the line that is supposed to attach to the drier won't fit, the end that goes into the drier is too big to go into the hole. There may be a difference with the JDM driers or a difference with R-134a driers.

The kit is designed to be used with the HKS RS intake, but whatever intake you run will need to be pushed to the side as the IC takes up quite a bit of room up front.

There is a nice, heavy gauge bracket that sits in front of the motor that holds the fuse block(s) and a small battery. The instructions call for a 38B19R battery, after doing some digging it looks like in the US it's called a 151R battery and is a stock 12v battery for the 04-06 Honda Insight. It's quite small (think Miata battery).

The PS cooling loop is removed and sort-of bypassed with a long piece of hose. Personally I would get a small auto trans cooler and plumb that in for the PS cooler. Since the kit was made for a RHD car I think the method of hooking up that cooling loop is moot on a LHD car.

The nuts and bolts with the kit are all stainless metric hardware but the quality is OK. Instead of bolts with floating washers or flange heads they are kind of hardware store-grade bolts and they want you to use a lock washer and flat washer with each bolt. It would have been nice to have more JDM OEM-grade bolts, but whatever.

We have a long way to go before the kit is permanently installed, and even longer before we're starting the car for the first time. I'm leaning toward using an RX-8 AC condenser since it has a built-in receiver/drier and the whole thing is like $80 brand new.

I'll update this thread as I find more down the road. Big thing is doing some documentation on this for the future.

Also, I have a copy I made of the manual that I marked up after using Google Translate to translate it to English :). Most of the instructions are pretty straightforward though and don't really need translation.

Dale

That’s awesome, 2k for essentially a bolt on v-mount is a bargain, and from HKS too. I’ve got a RHD so this would probably be even easier to fit... tempting.

Thanks as always Dale for your contribution :)

Thanks for the review and insight as always Dale. I'll keep this in mind when I eventually go single turbo and large IC.

Dont' forget to share pics of the install process and final setup. :)

Some more observations -

- The kit has 2 very solid plates that bolt to the frame rails on either side, top and bottom. Everything attaches to these - the radiator, condenser, and intercooler. There's also an adjustable splitter panel that goes between the IC and radiator to equally duct air to each.
- The side plates have 3 brackets riveted on for the AC condenser to bolt to. It is designed for the JDM Nippondenso AC system, but after looking at it it could be modified for the US MANA AC system. The rivets could be drilled out and the brackets moved to the appropriate locations and riveted back on. There's no WAY you will install the kit without discharging the AC system, one of the AC lines goes through the side panel and you have to flip it over so far you'd never accomplish that without destroying the lines.

Unfortunately it's going to be a bit before I tear into it again since I'll be going out of town for Thanksgiving, but I'll be back at it :).

Dale

Dale,

Do you have an update to this yet? I am considering purchasing the HKS V-mount as it is actually fairly cheap from RHDJapan and I like the intercooler design and end tanks. I am mostly curious about:

1) fitment with the Koyo radiator
2) clearance between the radiator fans/shroud and ground

I recall reading a few posts from over a decade ago that mention the radiator is very low to the ground with this kit and a thicker radiator, but I am curious whether they ever updated the kit to correct this.

We are slowly getting there with this kit. It does accommodate a Koyo with the clamps that go around it just fine - it is adjustable for radiator thickness.

The fans are pretty low with the kit, but I'm not sure yet HOW low, we don't have the belly pan yet and are waiting on brackets to come back from powder coating right now to start really putting things together.

The good side/bad side of the kit is using a standard radiator. If you need to replace the radiator it's no big deal as far as getting the part, but there's a lot of compromises to do so - it's kind of odd how the radiator mounts and the fans are on the low side.

Everything else in the kit is top notch, the brackets are super nice, the radiator is gorgeous, nice throttle body elbow, etc.

Dale

Thanks for the update, very helpful. Looking forward to seeing how it all fits up.

Getting closer and closer to being DONE with this install and having a running car.

Few small things I've discovered so far -

- Prepare to do some semi-minor wiring work. The fan wires need to be lengthened a good bit. Also, since the positive battery terminal moves a good amount to the small battery in the battery bracket, some of the wires going to the fuse box on the positive terminal will need to be extended. In theory you could leave the fuse box over to the side somewhere and just run a thick cable to the positive terminal but that's a lot of places for potential failure. Also, there's a decent size (12 gauge?) wire going from that fuse block to the other underhood fuse box that's WAY too long since they are located right next to each other. I'm going to make a replacement wire that's much shorter.
- Same goes for the negative battery terminal's ground to the chassis, the bracket it originally attaches to is no longer there. You have to get a little creative.
- You really have to study the pictures in the manual to figure out how to run the pipes for the radiator. Also, since you have to cut up a stock radiator hose for the connections, the hose should be a new-ish hose. An older hose has expanded some so it won't fit tight on the ends.

Some pictures of the radiator hoses -

https://cimg0.ibsrv.net/gimg/www.rx7...53b22476a4.jpg
https://cimg3.ibsrv.net/gimg/www.rx7...161e33faff.jpg

Dale

Soooo.. i have this kit and im Keeping the AC . What do i need or not need to do this?

We have the instructions in English on our site.

http://www.banzai-racing.com/store_i...04_v-mount.pdf

Thank you sooo much!!

i installed this kit back in 2012 with No instructions.. i hated the installation so much... i wish i had this then. Thanks Chris

Dale I replaced the oem fans with single speed fans from spal 1470 cfm each. Low profile fans bolted on the radiator thru the radiator fins and a half condenser from HPI. I would like to put the oem fans back and perhaps use the rx8 condenser. My ac is ok but ok it could have been better..

only thing i really want to do is to replace the radiator with one that has both inlet and outlet on the same side so i can avoid the bent up tube ...

Curious Why back to the OEM Fans? i Bought this Kit second Hand and it came with Dual Spal Fans as well. I've been told the RX-8 Condensor is the way to go but not sure why either.

i have been using the HPI half condenser.. AC is not cool enough.. i do feel that the oem (99spec fans) are far superior than the spal ones that i have. Perhaps some ducting/shroud might help this issue..

i also like the multispeed option that you cant have on this setup..
car runs cool dont get me wrong. Track days at 100+ F degrees ambient temps and no issues... yet again my AC is weak ..
i bolted the fans directly on the radiator. Perhaps a shroud between them might fix the issue or upgrade (again) to more powerful fans

Use the RX8 motors and blades with the OEM RX7 shroud. These pull more air than any of the OEM RX7 fans, are quieter, and use less amps. Here is the thread in this section where we have been having a discussion about these fans.
https://www.rx7club.com/3rd-generati...-leak-1128591/
Mike

not true...
Rx7 96+ fans and rx8 fans are the same

That may be true for later model RX7's, if you have one.. I am talking about USDM '93-'95 models. The motors may be the same or similar but the fan blades are definitely different. The size and number of blades is different. The RX8 blades do not fit on the OEM USDM RX7 motors. The fan noise is quieter and the amperage draw is less. Also, a full shroud on a radiator makes a difference in cooling effectiveness since it forces or draws all of the air from the radiator through the fans and therefore the heat exchange is improved particularly stopped or at low speed. At higher speed the effectiveness is obviously less significant.
Mike

purchased this kit. My car is Rhd so hoping the intsall will be simple. I have a SARD oem position radiator so im glad to be able to retain that. My car is 97 so i assume i have the better fans? hope they dont hang too low. Will update when it finally comes.

subscribed

Any good sources for a 151R battery? preferably AGM

it does not seem to be a common size in the USA

So far i'm half way into my install. I have the radiator air guide and also the ac hooked up. I bought this kit used off of ebay and bought it knowing a few parts were missing. But its fairly simple to install especially with the english guide. Had i bought this new i would had probably been done by now. The kit comes with everything u need and honestly its worth every penny. They think of everything and provide everything. I have the Intercooler to mount up now and the power steering relocation tube. So far so good

Dumb question here. Does this kit retain the stock OEM front undertray, or is that removed?

I don't have one but I personally can't see how you would retain it here. The fan drops a bit further down and would probably need you to cut the guard

Finally got everything up and running . I have a busy schedule and did a few bits and bobs every day before going to work. Having English instructions made this a breeze. I got my kit used with a few things missing. No ac lines or battery / harness brackets and the hot side pipe was designed for a single turbo. But for the price I got it for it was worth it. Relocated the battery to the trunk and made my own fuse box mount and Ast mount . Bent a few a/c lines and made a loop for everything to work. Fans are low but not rediculous. The kit is absolutely beautiful and so happy to have it.

https://cimg5.ibsrv.net/gimg/www.rx7...73a8cf4a13.jpg

how high off the ground are the fans? Do they scrape on speed bumps?

I haven't driven it yet and need to drive over 5 speed bumps just to leave my complex. I suspect I will be fine. The only thing that really hangs low is the front plastic frame surrounding the fan. It's really not bad. Unless your car is slammed

Can't remember. I just had some spare wire that was the same size as the stock wiring, I didn't look for a particular gauge.

You can easily get a roll of wire at the auto parts store that's the right size. It's probably 16 or 14 gauge, somewhere in there.

Dale

Dale, thanks again for the thread. It looks like the fans are about 14awg, some of those wires in the fuse box are another step or two up.

I really wish there were more documentation on this kit. The manual is great at telling you what you need for each step but then the illustrations are next to useless. I've been working on cars for 15+ years as a hobby and this has made me feel like an amateur. I will try to take a bunch of pics to share.

So far I've got my rad + fans, condenser and air splitter mounted. I test fitted the intercooler and radiator piping yesterday. I do not have much room for that pipe that goes from the front of the rad, routing as Dale has it pictured will result in some rubbing as it stands. Going to play with it some more but I'm really itching to get this done as ive had my car since October and I think its been on the road a full two months of that with upgrades and replacements in between.

Also, I have a RHD 92 model. The ac lines do NOT work. The routing looks the same but the ends will not go to my oem stuff. Hoping I can swap the ends of my factory lines over or something to get that sorted. My a/c was blowing the fuse but i'd like to have it in the future as summer SUCKS here.

Dale, sorry to hijack your thread. I just thought it would be good to have more in one place. Did you try out that Honda Insight battery? I have a 40B19L and it fits but the posts are on the wrong side. My only concern with the Insight battery is its almost an inch taller, have to check the thread length on the bolts for the tie down.

Also, im curious how others did the rear fan shroud stays. It says to use zip ties around the provided brackets but I couldnt figure out a way to use zip ties without drilling holes into the shroud for them to go through.

Here are a few more photos and some comments:

I moved the relay box to this position so it wouldn't be blocking any air. I could not find any more length in the wiring to make it point upwards as ive seen on other installs. You can also see my fan extension wires and routing on the right. If you look carefully at the radiator mount on the bottom left, I added a few washers to offset the radiator more to the right to provide more clearance for the hose shown in the next picture.

You can also see one of the drains in the radiator here, it has one in the same spot opposite end so should be no trouble to drain, other than this one landing right on my bumper. Will cross that bridge when the time comes.


https://cimg6.ibsrv.net/gimg/www.rx7...bed33764b.jpeg


With the Koyo, this area is very very tight. I was able to mash it in there without it constantly sitting against something else but there is a little bit of wiggle in everything so I added some insulation from my old radiator hoses to hopefully keep down any metallic rattles from the movement.

https://cimg8.ibsrv.net/gimg/www.rx7...50be4715b.jpeg


Battery tray here, very nice piece. I was able to attach that ground without any trickery or modification.

https://cimg0.ibsrv.net/gimg/www.rx7...19c602eef.jpeg

AST and included mounting bracket on opposite end of battery tray. I ended up changing this after the photo. I have a RE Amemiya AST. Installed like this it wanted to occupy the same space as the intercooler pipe that goes above it. I took a small flat bracket and bent it to hang off of the battery tray and then the AST mounts to it. This moved the AST to picture left and got rid of my space issue. Sits directly under the intercooler pipe now.


https://cimg2.ibsrv.net/gimg/www.rx7...ad34097c8.jpeg

We did use that Honda Insight battery, ordered it from Pep Boys. Been working fine, it fit perfectly.

Don't know what you mean about the fan shroud needing zip ties, it should all attach with the various brackets that come with the kit.

Dale

Just a FYI for anyone considering the HKS intercooler for big power (500rwhp+). It does not like a lot of boost and cannot cool a large displacement of air. Mine failed a few years ago before I upgraded to my current setup.

It is still a great kit for normal boost levels and is complete. The radiator fans do hang very low so it will require some vigilance to keep you from tearing them off of the car. Unfortunately, I have torn them off due to road damage around a blind turn.

https://cimg4.ibsrv.net/gimg/www.rx7...9e3928eb3f.jpg
https://cimg6.ibsrv.net/gimg/www.rx7...6ceb4af09f.jpg
https://cimg7.ibsrv.net/gimg/www.rx7...67db9906f6.jpg

Wow, good to know.

Mine has been doing great. Still no issues and have driven the car a fair amount.

Sorry to see that damage. Can I ask what your new setup is? And effectiveness of cooling iats etc vs hks solution?

I'm probably a bad example to follow. I went with a custom 2000HP A2W intercooler setup. It's apples to oranges on IAT's, they no longer move. It's not a very street friendly setup in comparison.

Instagram

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still have the bits and pieces from your hks kit? i was wondering if i could get a few things

Thanks

Can you elaborate on this a bit?

My car is atypical of most RX-7's but I'll give you my take.

First you have to consider that the air-to-air intercoolers on most cars, simply just work; There is no effort involved. Sometimes we upsize them to better handle capacity.

So if you're comparing an air-to-air to an air-to-water, there are trade-off's. You do get additional capacity, but really there is no reason to upgrade if you're not overcapacity on your current intercooler.

I typically don't suggest going air-to-water unless you absolutely have to. I was well past what could be handled by an air-to-air intercooler on my setup. By well past, I would flash the HKS v-mount in less than 330ft from a dig. 80F AIT to 190F+ AIT (logged) on a cold engine in less than 4 seconds (possibly higher as the AIT sensor will have some lag).

So I was forced to find an alternative solution. It looked like even a bigger, front mounted A2A would barely work, and barely is just not going to cut it; especially with goals of 45+psi. Hindsight: I should have tried the bigger A2A but I wanted to go overkill. I did not want a repeat issue.

So the cons of an A2W vs A2A:
You can heat soak the A2W and it will take a long time to cool off. You can install a heat exchanger but there is just not much room for an adequately sized one, so you still heat soak.
More components to buy.
Added complexity to a simple component.
It weighs substantially more than your standard air-to-air intercooler. Mine adds around 100lbs to the car (pump, tank, 5-7 gallons of water, lines, intercooler, etc).
You need to wire and plumb the intercooler and intercooler pump in the car.
The cost on the air-to-water intercooler is much higher.
They take up a lot of real estate in the engine bay.
You need a water tank, thus eating up more real estate (either in the trunk, or in the engine bay).
More electrical load on the car which doesn't have much free capacity.
Takes another output from ECU to trigger. My car already has an expander box so outputs are limited.

The benefits of the A2W vs A2A:
You can go sub-ambient temperatures for a single pass. (It melts any ice in one run, and doesn't stay sub-ambient)
You have more overall capacity to hold heat. This results in more consistent air temps at higher boost.
You can run the pump and cool the intercooler before start-up. You can also just install fans on the A2A, so this is kind of useless.

So essentially, it's better for a drag car. You can run ice for a single pass, then re-ice the car and go. I made it work for my street car but the trade-off's are worth mentioning and not many rotaries are running 35psi as "low boost".

Getting completely off-topic of the HKS IC, but IRT heat exchangers, wonder if anyone has tried hooking up the A/C evaporator as an IC?

Answering my own question

Using AC For A Cooler Boost Charge - Speedhunters

I've looked into it, it's done fairly regularly for supercharged cars. A lot of investment for not a lot of extra performance over an A2A though. Usually by the time you have an A2W, you no longer have A/C anyway.

I just completed installing the kit. It took me about 3 full days to install it in the road in front my house. This was with plenty of breaks and fiddling around with things. I could probably do it in half the time if I were to do it again.

There were two bolts in my kit that were definitely too short for their intended purposes, so I had to make a trip to the hardware store. I was also disappointed with the usage of the oem rubber radiator mounts for the splitter. Bolted together, the threads on the oem pieces barely stick out enough for the supplied nuts. Otherwise, the kit went together well, and I found the instructions sufficient.

Crusing around during an 85-90F degree day, my water temps were somewhere around 80-90C degrees and air temps stayed around 43C degrees. This is with a Koyo N-flow.

https://cimg5.ibsrv.net/gimg/www.rx7...ff9b79d331.jpg

For the fuse box in the front, I managed to get mine zip tied pointing upwards by pulling the harness its attached to down a bit. The harness the fuse box wires are attached to is tucked up into a slot with a plastic bracket. You can pop the bracket and harness off the metal support, remove the plastic bracket from the harness, and pull the whole harness down to get enough length.

Why would someone want a $3k v-mount kit on a factory twin turbo system with a single 25 year old oil cooler?
I think a $250 W/M injection system would work better.

We need more info on the effect of iats with this kit on the twins. It’s a hell of an investment to make cost-wise for me. Many thanks on sharing.

I would like to know how quickly iats drop when heat soaked and transitioning from a stop to moving on city roads vs interstate hwy speeds. What boost are you running etc. Also what happens during boost. Do you still see rises in iats or are they nominal changes?

I am looking at AI also but think the mechanical solution of a vmount is a better approach than the risk of a failure in an AI solution.

Tommykaira, thanks for the photos. I need to go back in and try to get my fuse/relay box like yours.

Nakd N Fearless, the kit was only $2k+ shipping from japan for me, new. W/M adds a potential major failure point and i'm not very familiar with it or the tuning aspect. A v mount is pretty much bolt on and forget.

Aarkaah, I plan to hook up my wideband to the datalogit soon and then i'll do some logging. Will post in thread once I do so.

We're in the middle of a heat wave here (97F), so I took the car out for a more thorough shakedown and noted some numbers. All my numbers are from the PowerFC.

The car is a 93 touring running stock turbos at 10 psi. Strapped to the Koyo is an unknown quality of aftermarket fans. One of the fans is broken and the other is wired to run continuously.

After warming up the car and driving it around town for 20 minutes, I took it on the highway and drove it a steady 65-70 mph out of boost.

After 10 minutes
water temp 80C
air temp 47C

Then, I pulled over and let it idle for 10 minutes. Water temp 98C
Air temp 64C

Driving back down the highway for 5 minutes, water temp dropped to 92C and air temp dropped to 52C. I got off the highway and temps were back down to 84C and 49C after 5 more minutes of light throttle and a few stop lights. I drove it around town for the next 15 minutes, in and out of boost, and I didn't notice much of a difference. Final temps before I shut it off were 84C and 48C.

Reviving this thread from the dead.

What are some solutions you guys came up with regarding the under tray clearance issue with the fan shrouds? I was under the impression that running the under tray was necessary for temperature cooling efficiency, and being that I live in the dreadful state of New Mexico the roads are horrible and covered with debris.

Suggestions would be greatly appreciated!!