Bob's 3.7L M90 Supercharged Build

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dopes6070

Discussion Starter · May 13, 2016 (Edited)

Here is my current progress. Going to use the stock intake mani spacer to keep the torque curve low. Already have KTuner and Bisimoto is gonna take care of the actual tuning.

305hp on tap will be a HUGE improvement. :grin:

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dopes6070

Discussion Starter · #21 · May 14, 2016

Since the VTM4 diff is clutch based, it can only transfer a fixed amount of torque. As long as I'm not spinning the front wheels there should be minimal extra wear to the rear diff. At least that is my thought on it.

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speedlever

· #22 · May 14, 2016

I confess that I've never understood the mechanism by which Honda limits the power transfer to 70% to the rear wheels. (or transfers up to 70%, as has been advertised).

Is clutch slip the mechanism by which only 10% (as directed by the ECU) is sent to the rear wheels? Or what limits the power going to the rear at 70% max?

dopes6070

Discussion Starter · #23 · May 14, 2016 (Edited)

The way I understand it, the VTM-4 diff is controlled through pulse-width modulation to the coils inside the unit. The coils squeeze clutch packs to create friction. This friction is what drives the rear tires up to 70% of the engines available torque. The 1G RL's VTM-4 design has similar clutches to an automatic transmission except it's electronic vs hydraulic. Due to a limitation of the coils capability to shed heat they cannot increase the holding power any further. This is why the new VTM-4 system is hydraulic

Now in my situation it will max out sooner, being able to transfer less of the engine's output. This means I could potentially get front wheel spin and damage the rear differential. I figure as long as I'm not an idiot I won't have any problems... At least that's what I hope for. Worst case if I do grenade the rear differential, it's much easier to replace than the transmission and they're a dime a dozen.

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RustyH

· #24 · May 14, 2016

I'm curious why you didn't (or couldn't) use the transaxle that came with the Acura engine. Supposedly you wouldn't have to worry about the horsepower blowing up the transmission.

Would you loose the 4WD option, but earn a full time AWD? Does the Acura AWD set up fit in the Ridgeline? Would you have to change out the rear Axle as well.

For a street truck, that seems advantageous, but if you're going off road a lot, maybe 4WD is needed.

dopes6070

Discussion Starter · #25 · May 14, 2016

Actually if I were to pull the 5at out of an Acura TL sh-awd its direct bolt in. The transmission is essentially identical as far as I know. The RL trans is very bulletproof and really isnt a weakness like previous Honda automatics. It fits perfectly with the swap and gear changes are crisp and quick even with WOT runs.

The sh-awd diff will not fit without rear subframe modifications and then it's a matter of figuring out how to make the electronics control it. I wasn't feeling overly ambitious at this point to tackle that. Really I would prefer one of the new hydraulically controlled vtm-4 or shawd differentials.

RustyH

· #26 · May 14, 2016

So you say the weak link is the Ridgeline rear diff. Can you pull the drive shaft to the rear and make the truck full time Front wheel drive, or would there still be a bunch of electronics to deal with because the truck would be looking for rear diff feedback.

dopes6070

Discussion Starter · #27 · May 14, 2016

Actually if the driveshaft is removed the truck will behave like normal but fwd. Unfortunately the torque steer would be unbearable for me so I'm gonna keep it as is. When i punch it off the line all I get is a small chirp from the front on dry smooth pavement.

This thing is a rocket once the iVTEC switches cam profiles for the intake and exhaust. It pulls hard! Whoever said the j37 swap was a dog in the RL did something wrong!

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RustyH

· #28 · May 14, 2016

I've got an '06 with around 130K, still running strong, but now that I've seen yor swap, this may be the way to go later down the road. It will be interesting to see, after the tuning is done, how this combo does on the Dyno. I know since you're in CA, you've got to meet a lot of emmission testing, but if this passes CA smog testing, it should be good for AZ.

dopes6070

Discussion Starter · #29 · May 14, 2016

Emissions testing wouldn't have been a problem IF I had the stock precats and j-pipe. It just depends on how detailed the person doing the visual is. CA stopped doing the sniff test a while ago so as long as you pass visual and OBD2 checks they send you on your way. I'm not sure how AZ does it.

speedlever

· #30 · May 15, 2016

dopes6070 said:
The way I understand it, the VTM-4 diff is controlled through pulse-width modulation to the coils inside the unit. The coils squeeze clutch packs to create friction. This friction is what drives the rear tires up to 70% of the engines available torque. The 1G RL's VTM-4 design has similar clutches to an automatic transmission except it's electronic vs hydraulic. Due to a limitation of the coils capability to shed heat they cannot increase the holding power any further. This is why the new VTM-4 system is hydraulic

Now in my situation it will max out sooner, being able to transfer less of the engine's output. This means I could potentially get front wheel spin and damage the rear differential. I figure as long as I'm not an idiot I won't have any problems... At least that's what I hope for. Worst case if I do grenade the rear differential, it's much easier to replace than the transmission and they're a dime a dozen.

So basically the amount of power that goes to the rear wheels is a function of how much or how little clutch slip occurs as determined by the ECU?

I.E., a lot of slip means a small amount of power is directed to the rear wheels and a little bit of slip means the max amount of power is going to the rear wheels?

If that is the case, I wonder why there is so little debris on the rear diff mag plug when I change the VTM-4 fluid? I see much more debris on the tranny mag plug and I change tranny fluid much more frequently than rear diff fluid... About 2x more often (every 13-14k miles for tranny vs 30k miles for the rear diff).

48218

· #31 · May 15, 2016

It's maybe useful to think of it slightly differently. The max torque applied to the rears has to do with traction conditions. The control system applies a certain amount of clamping force based on its calculations. If you're driving away from a stop sign, it may still clamp the clutches, but there will be no clutch slippage because there is not a traction problem at the front tires, and the driveshaft going rearward from the tranny never spins faster than the output shaft going to the front diff/wheels.

In that circumstance, Less than 100% of available torque was applied to the rear wheels, but there was no clutch slippage.

dopes6070

Discussion Starter · #32 · May 15, 2016

bulwnkl said:
It's maybe useful to think of it slightly differently. The max torque applied to the rears has to do with traction conditions. The control system applies a certain amount of clamping force based on its calculations. If you're driving away from a stop sign, it may still clamp the clutches, but there will be no clutch slippage because there is not a traction problem at the front tires, and the driveshaft going rearward from the tranny never spins faster than the output shaft going to the front diff/wheels.

In that circumstance, Less than 100% of available torque was applied to the rear wheels, but there was no clutch slippage.

Very good point! This is exactly why im not worried about reliability. As long as I'm not sitting spinning the tires I'm sure ill be ok!

dopes6070

Discussion Starter · #33 · May 15, 2016

Gave the engine bay a quick simple green and hose down. Theres still some dirt but at least its clean-ish now!

Was driving and the fuel trims are way way off. It is running rich and the ECU is pulling a lot of fuel. I just sent out my first datalog to the tuner so hopefully it will start getting closer.

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dopes6070

Discussion Starter · #34 · May 15, 2016 (Edited)

A couple notes If anyone does this swap. The RL injector Clips will not fit the J37 Denso injectors, they are different. All you need to do is remove the pins from your factory clips and put them into the injector clips that come on the TL engine harness. Also, use the ZDX air intake tube with a 3.5" 30-degree aluminum elbow to meet the filter housing with a 3.5" coupler. It is much cleaner trying to use as many factory parts as possible.

My list of things to complete...

1. Get correct hose clamps for ZDX intake tube
2. Paint aluminum elbow matte black
3. Replace intake mani cover with accord v6 MT part for a more factory appearance. I could use the Ridgeline intake manifold cover but it's ugly and I don't want to put the plastic back on
4. Finish street tuning
5. Take the RL to Bisimoto for the final tuning and dyno

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OhSix

· #35 · May 16, 2016

dopes6070 said:
A couple notes If anyone does this swap. The RL injector Clips will not fit the J37 Denso injectors, they are different. All you need to do is remove the pins from your factory clips and put them into the injector clips that come on the TL engine harness. Also, use the ZDX air intake tube with a 3.5" 30-degree aluminum elbow to meet the filter housing with a 3.5" coupler. It is much cleaner trying to use as many factory parts as possible.

My list of things to complete...

1. Get correct hose clamps for ZDX intake tube
2. Paint aluminum elbow matte black
3. Replace intake mani cover with accord v6 MT part for a more factory appearance. I could use the Ridgeline intake manifold cover but it's ugly and I don't want to put the plastic back on
4. Finish street tuning
5. Take the RL to Bisimoto for the final tuning and dyno

Beautiful! Looking forward to your dyno results. By chance is there a pre-swap dyno run to compare to post-swap?

Also, I'm damned happy to hear you're going with correct hose clamps on the intake tube. Everything is soooo damned purdy, my OCD was shorting out over the orientation of the clamp head closest to the throttle body. :nerd:

dopes6070

Discussion Starter · #36 · May 16, 2016 (Edited)

OhSix said:
Beautiful! Looking forward to your dyno results. By chance is there a pre-swap dyno run to compare to post-swap?

Also, I'm damned happy to hear you're going with correct hose clamps on the intake tube. Everything is soooo damned purdy, my OCD was shorting out over the orientation of the clamp head closest to the throttle body. :nerd:

Theres also a missing clamp at the throttle body that has since been rigged with a zip tie. I dont have anything that will fit and there is an indexing rib in the way on the intake tube. FYI my OCD is costing me almost $20 for 2 hose clamps haha! Waiting (im)patiently for parts to deliver to tie this thing up. Took it out on the freeway and man this thing is epic. It no longer hunts around on the smallest of hills. It no longer feels underpowered like it did at low RPM. The low end is great and the high end is totally honda!!!

I think I'm in love!!! >

dopes6070

Discussion Starter · #37 · May 16, 2016

I did not do a pre swap dyno because we already know that these trucks make about 190-200hp stock at the wheels depending on conditions. I should hopefully have about 240+ whp when all is done. My biggest goal is torque though, and the 3.7 definitely delivers. Sorry for the double post.

eurban

· #38 · May 17, 2016

Dopes,

Very interesting swap! Makes a lot more sense to me to give the Ridge the low end grunt that it needs rather than mods that give it more power at high RPMs where I am almost never spending any time. . .

Can you give some more details?
Year and model range of Acura donor vehicle?
What parts other than the engine need to come along?
How much $ do you expect to pay on the tuner end of the project?

Please keep the updates coming. Very interested in performance as well as things like gas mileage etc.

Thanks!

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dopes6070

Discussion Starter · #39 · May 17, 2016

eurban said:
Dopes,

Very interesting swap! Makes a lot more sense to me to give the Ridge the low end grunt that it needs rather than mods that give it more power at high RPMs where I am almost never spending any time. . .

Can you give some more details?
Year and model range of Acura donor vehicle?
What parts other than the engine need to come along?
How much $ do you expect to pay on the tuner end of the project?

Please keep the updates coming. Very interested in performance as well as things like gas mileage etc.

Thanks!

I know for a fact that the 09-2013 TL SH-AWD engine will fit the 09-2014 ridgeline. Prior 06-08 RLs I am not sure and would need to do some research. The bigger issue for 06-08 is that KTuner does not yet offer support. Send them emails and buy our RLs will become a higher priority

Here is where I am at currently.

Before the swap I tore into the J37 and did the following… Timing Belt, Water Pump, Spark Plugs, F &R Crank Seals, Cam Seals, Valve Adjustment.

· My truck is a 2013 Ridgeline RTL

· Swap Started at 41500 Vehicle Miles

· 3.7L Acura TL SH-AWD J37A4 Engine w/ Intake Manifold 52k miles (any J37 will fit, decide based on goals... the J37A4 is best)

· 3.7L Acura RL Throttle Body (since engine didn’t come with one and the Ridge TB is smaller)

· 3.7L Acura ZDX Air intake Tube w/ 3.5” 30° aluminum bend to reach stock airbox. (Stock rubber tube will not fit larger TB bore… Buy the ZDX hose clamps too)

· Stock ridgeline Intake Manifold spacer is installed for optimal low end torque

· RV6 Pre-cat Deletes

· RV6 J-Pipe (w/ stock 3rd Cat)

· 2012 Accord v6 MT Intake Manifold Cover (on order)

· K-Tuner – eTune by Turbogixxer (in progress) - Dyno session + final tuning by Bisimoto about a month away

· New Honda Air Filter

· 5w30 M1 High Mileage Engine Oil (will not use 20wt oil, too many cases of engine damage, cam wear etc…)

· Remote spin-on ATF Filter

· Everything Else is Stock…

Random stream of thoughts:

Definitely Install the IM spacer into whatever 3.7 you choose for the RL. This “truck” is heavy and needs all the twist it can get!

Keep the J37 Denso Injectors, They are larger. Also use the injector clips from J37 wire harness.

GET TUNED! KTuner works INCREDIBLY well...

To ensure parts compatibility, do some research on any Honda parts website. They have drawings that are really helpful. Google image search and eBay are your friends for finding pictures of anything for comparison.

BIG HINT: Take ALL accessories off the j37 and install the ridgeline parts. This includes the right side mounting bracket which can’t be removed without removing the crank pulley & lower timing cover. Wire Harness, Coolant Passage, Evap connections, AC Compressor bracket, P/S Pump bracket from the front head.

Don’t let the crank pulley bolt ruin your day… This goes for timing belt jobs too. These are torqued to 180ft lbs. I had to use a ¾” Impact with a ½” air hose and regulator to break the donor engine CP bolt loose… BE Warned. I tried a ¾” breaker bar with 3’ cheater pipe and the ½” breaker bar on the pulley holder tool was flexing A LOT. I didn’t want to break the smaller Proto breaker bar so out came the dinosaur ¾” impact. The thing came off in 2 seconds

I was wrong about the transmission being exactly the same as the TL SH-AWD… It is VERY SIMILAR but the TL does have one extra friction and steel in the 3rd clutch pack. Time will tell how the RL tranny handles the power. I will be sure to update this thread if there are any issues at all. If I blow the RL trans I will weigh my options at that time. *FYI if my driving style doesn't break it nobody's will...

Dyno tuning will be done with rear driveshaft removed as the VTM4 system does not allow consistent results on a 4WD dyno due to the variable electromagnetic clutches. I budgeted $600 for tuning. Some could get it dont for about 300-400 but I demand perfection.

Im averaging about 15mpg and thats including WOT runs on every drive for the tuning process. It will get better once im not datalogging.

ONCE AGAIN >>> GET TUNED! Don’t flake out on the most important step!

That is all for now guys

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eurban

· #40 · May 18, 2016

Thanks for the additional info!

To be clear . . .All the wiring harnesses are Ridgeline?

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