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Thank you both for informative posts.

Update on the IC and drivability: I continue to be impressed by the hood scoop effectiveness, even with the different shape of the duct and the gap between the duct and the intercooler. I have yet to check it and have it be other than cool to the touch immediately after driving...doesn't mean it's optimized, but it's a heck of an improvement. I was eyeing the IC angle (relative to horizontal), because it differs considerably from the kit angle so as to make it (I think) more conducive to airflow from a hood scoop. Standard installation makes the IC essentially horizontal/flat, which implies a harsh 90-degree change in direction of airflow, or even steeper ~110-degrees considering the angle of the hood, if a hood scoop is providing air flow. In order to get the whole thing wedged in under the hood, I had to install it at (what looks like) a 20-30 degree angle forward, which I assume offers a smoother flow passage to air coming in from the front of the car during travel. Drivability continues to be great (excepting the shift flares), and I recognize an increase in power due to the cooler intake temperatures.

Since the flares had been happening for a pretty long time, I noticed something, and I also researched into fluids and kits for the transmission. What I noticed is that, even before the fluid change, the flares were much less significant right when I started driving. After the fluid change, even after the TCU apparently readjusted settings for mushy, flaring upshifts, the flares are gone during that period. So, what it seems like is before the fluid warms up (when it has higher viscosity), one of two or a combination of two things is happening: 1) Increased viscosity, due to lower temperatures, is causing more solid shifting (suggesting that a fluid with a higher viscosity rating in general would improve shifting); 2) The TCU is programmed to treat shifting differently while the fluid temperature is lower (and thus in a higher-viscosity state... IE below standard operating temperature/viscosity). This suggests the option of using fluid of higher viscosity rating either by itself or in the form of a cocktail (as suggested by Mainia) and/or using a transmission cooler. However...

More viscous fluid negatively affects gas mileage...apparently to a significant extent. It seems clear that this is the reason for OEM ATF recommendations progressively moving toward less viscous ratings. Earlier, when researching, I was comparing OEM, Valvoline MaxLife, and Redline D4 and D6, along with looking at valve body kits for the U151. I went with MaxLife because of its excellent reputation, affordability, and because it apparently is slightly more viscous and more shear-resistant than the OEM stuff. There is some confusion (possibly even at Redline) as to the recommended fluid in these newer transmissions, because D4 is quite a bit thicker, and D6 is pretty close to the thin OEM stuff. I suspect that D4 is okay to use in a lot of cases but TCU programming in some cases can't match up its thickness with programmed shifting behavior, and additionally, it causes reduced fuel economy...which leads to a safer and more economical recommendation of D6; Not at all sure about this loose conjecture.

Mainia, I am interested in cocktailing, and am curious if you have any more detailed information or thoughts about advantages. I read a little about it before, but couldn't find enough reliable info to actually feel confident enough to put a mix together. Specifically, I am curious if you or your expert contacts know anything about properties beyond a simple viscosity average; Does it behave more like the lower-viscosity fluid when cruising (good gas mileage), and more like the higher-viscosity fluid when you "get on it", sort of like the expensive fluids that have increased resistance to flow when under greater pressure/torque?... I know the oil in the supercharger itself has this quality, which is how it engages (and that oil is very expensive). Also, have you kept track of gas mileage, or noticed any decrease or change, when using different fluids or cocktails? I have not done any extensive logging yet, but fuel economy seemed to be pretty close to the same after I put in the MaxLife. Would you be interested in sharing info about any of your chosen mixes? Thanks for the links to sources for the quality parts you mentioned.

I found a post on a Honda forum, which I am not sure I'm allowed to link here, but it's on-topic so I'll give it a shot. Feel free to delete it, obviously, if it violates forum rules. It touches on reduced fuel efficiency from using thicker fluid, but in the 6th post, someone posted a picture of a chart of fluid viscosities which seems pretty interesting (and claims a slightly-higher viscosity for Redline D6 when compared to Valvoline MaxLife): Redline D4 vs DW-1

That post also made me very curious about transmission coolers, and whether and how much they affect fuel economy. Supposedly, according to the above linked thread, someone lost 5-6 MPG in a Honda Odyssey by using a fluid with about a 10% higher viscosity index (6.83 - OEM vs 7.50 - Redline D4, at 100 degrees C). Judging by the chart, temperature affects viscosity, probably more than that... In other words, with a transmission cooler, if the operating temperature is 10- 20 degrees C cooler under normal conditions, that suggests a similar, if not greater, increase in viscosity than 10%. So, how does fuel economy add up with fluid vs fluid, transmission cooler vs none, and a combination of the two?

Myxalplyx, I looked for shift kits, too, and didn't see any. I did find some zip kits by Transgo and Sonnax which supposedly target known transmission issues, including 2-3 and 1-2 flares. I actually purchased the Transgo kit, but I'm not yet sure whether I'll install it... leaning toward doing it, though, especially if it tightens up those two shifts without messing anything up. Something like a shift kit (or valve body modification) seems like an ideal solution, if it can retain fuel economy while tightening up shifts.

I also happened upon a Youtube video which was made by a transmission mechanic specifically about the U151. He said in the video that he replaces 3 of the U151 solenoids any time he has to work on one, without even checking them. Probably a time/money efficiency thing, but it makes a statement as to another possible cause of shifting issues.
 

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Discussion Starter #142
**Brief update**

No new news! Car drives just fine. Just wanted to say that I've mentally pulled the plug on getting my maf sensor piping redone so it doesn't throw a code. On another note, I will be having a front mounted intercooler installed. I'll have to work my arse off this summer but it's going to happen. The intake temperature being 100F+ over ambient just keeps eating away at the back of my mind. Also, I'm positive this is the only thing keeping this car from running in the 12's and that continues to bother me, despite me not racing at all this year. So...when this happens, I'll update with pics, etc and no doubt some new timeslips. In the meantime, the car drives with zero issues. Actually, its been sitting a lot since I've been driving my Civic (which I will also be modifying a touch this summer). Stay tuned! :smile

biyanpian: Can't wait to hear/read whatever you may have cooked up in the meantime. :wink
 

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fluid changes will not effect much or improve the flare shifting. there are only two ways to improve this- one is a rebuilt valve body (uses larger metering valves to improve the issues with this transmission). the other one is to shim the shift accumulators. My transmission started the dreaded flare shifts, I added a large transmission cooler to keep the fluid cooler- it did nothing but keep the transmission fluid super clean and red. I had to try two rebuilt valve bodies as the first one still flared, second one got it pretty good. Still soft shifts. Went on forums and found ford/chevy guys shimming their shift accumulators to make the shifts firmer/faster. I ended up shimming two (1st and 2nd) accumulators to half their travel and now its perfect. WOT shifts are crisp and quick, normal driving has no more flares. Accumulators are on-top of the valve body- very messy but dropping the trans pan is very easy. If anyone is interested maybe Ill post how it done.
 

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I recently also bought/installed the HKS supercharger on my RAV. I have to make a custom oil tank bracket for the supercharger oil supply and made an air to water intercooler in place of the useless and non-fitting top mounted intercooler. Water radiator for the intercooler sits in-front of the radiator. I installed 450cc injectors running through the stock air box. RK9 tuned but I can't drive it as its running so rich it barely registers above 10.2. Rich CEL codes and stumbles when cruising. Hopefully they get this sorted out. Im really dissapointed as I though the tuning was figured out, I never would have committed to this superchager (or any boost) if I had know I would be without a good tune.
I'll keep you posted. I may have to make my own MAF tube to tune the fuel- not the ideal situation.
I also made my own unequal length headers- trying to get that subaru sound and not the tinny sound these v6's have. I didn't get a final picture of the finished header as I changed this design. Cats are after the headers now, further down the line. Sound is subtle, not a pronounced as I wanted but still better than before.
 

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I ended up shimming two (1st and 2nd) accumulators to half their travel and now its perfect. WOT shifts are crisp and quick, normal driving has no more flares. Accumulators are on-top of the valve body- very messy but dropping the trans pan is very easy. If anyone is interested maybe Ill post how it done.

I would be very interested!...awesome build!Look fwd to hearing any exhaust clips and see what this will do once you have the tune fixed.
 

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Kevin, thanks for the updates and keeping us in the loop on the reliability! I was considering adding a SC to my ES, and this may be the one!

My concern is, looking at your sig, the SC in your RAV4 got you a half a second and 1 mile trap on the quarter. To me, that performance improvement wouldn't be worth the trouble with the SC. Is that correct? Does anyone else have the numbers?

The dyno numbers, do you have the NA pulls too, before the SC install?
 

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13.2 was his fastest quarter-mile time with the HKS kit, 13.7 was his fastest time with a slew of mods being NA.

I also don’t believe he paid full price for his kit either.
 

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The dyno numbers, do you have the NA pulls too, before the SC install?

Pretty sure he only did one Dyno run when he was completely stock and got a 199whp. Think he ran a high 14 bone stock as well.

If you do a forum search of all of his threads (there are lots of them) you can probably find those exact numbers...
 

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Pretty sure he only did one Dyno run when he was completely stock and got a 199whp. Think he ran a high 14 bone stock as well.

If you do a forum search of all of his threads (there are lots of them) you can probably find those exact numbers...
Ah ok, that makes sense. His sig a lil misleading :nerd
 

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I recently also bought/installed the HKS supercharger on my RAV. I have to make a custom oil tank bracket for the supercharger oil supply and made an air to water intercooler in place of the useless and non-fitting top mounted intercooler. Water radiator for the intercooler sits in-front of the radiator. I installed 450cc injectors running through the stock air box. RK9 tuned but I can't drive it as its running so rich it barely registers above 10.2. Rich CEL codes and stumbles when cruising. Hopefully they get this sorted out. Im really dissapointed as I though the tuning was figured out, I never would have committed to this superchager (or any boost) if I had know I would be without a good tune.
I'll keep you posted. I may have to make my own MAF tube to tune the fuel- not the ideal situation.
I also made my own unequal length headers- trying to get that subaru sound and not the tinny sound these v6's have. I didn't get a final picture of the finished header as I changed this design. Cats are after the headers now, further down the line. Sound is subtle, not a pronounced as I wanted but still better than before.
I am very interested in more info about the transmission... responding in this post because I might have some helpful info. The transmission is really the only unhappy thing about the setup. Sluggish shifts with ridiculous flaring on a low miles, dealership-maintained transmission (flushed at 50k, still has under 100k on the engine & transmission). I dropped the pan to change the filter, which was pretty straightforward... was considering pulling the valve body to install the Transgo kit, but didn't want to gamble without more certainty that it would address the issues. The info you posted is encouraging, and any additional detail you provide would be appreciated.

I am using 440cc injectors with the factory ECU... no real problems. Tip-in enrichment goes rich, as expected, but the ECU is able to manage fine in closed-loop (hovers around 14.7:1), and goes appropriately rich under boost... maybe even excessively rich (I see down to 10.0), but I am not complaining, since it isn't too lean. No stuttering. There is carbon on the tail pipe, so it could be adjusted with a piggyback, I assume. I bought an FIC 6 for that purpose, but have not seen a real need for it yet. I installed a wideband sensor on each header.

I was able to use the kit IC with a lot of trial, error, and careful modifications all around. I changed the recirculating valve. I installed a catch can. I also installed a very functional hood scoop, which in itself was a lot of work, but it was worth it. Attaching pictures (none of the hood scoop in my phone... let me know if anyone wants a picture of it).

Teksmart asked about the wideband bung locations, and I will try to get pictures... just a bit tricky to get to the one on the rear manifold.


Correction: After trying in two browsers, I can't seem to attach pictures. I get the error message: "Your submission could not be processed because a security token was missing." There is a link to notify an administrator of the error, so I followed it, and provided the relevant information. When submitted, I got another error message: "Invalid Post specified. If you followed a valid link, please notify the administrator". Har har. Until it works, I would be happy to e-mail or text pictures.
 

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Discussion Starter #151
My concern is, looking at your sig, the SC in your RAV4 got you a half a second and 1 mile trap on the quarter. To me, that performance improvement wouldn't be worth the trouble with the SC. Is that correct? Does anyone else have the numbers?

The dyno numbers, do you have the NA pulls too, before the SC install?
The SC got me a half a second and 1 mile trap on the quarter. You are correct! It's not worth the trouble with the SC.

Yes, I posted dyno pulls NA before the SC. Stock, with lightweight wheels, with exhaust muffler changed and testing intake. The before and after N/A results aren't as significant than you'd get with a 'properly fitted' boosted application. Very significant for me but you may be looking for something more in line with a Corvette, Supra or the like.

Sorry to mislead you with my Sig.
 

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Discussion Starter #152
I am using 440cc injectors with the factory ECU... no real problems. Tip-in enrichment goes rich, as expected, but the ECU is able to manage fine in closed-loop (hovers around 14.7:1), and goes appropriately rich under boost... maybe even excessively rich (I see down to 10.0), but I am not complaining, since it isn't too lean. No stuttering. There is carbon on the tail pipe, so it could be adjusted with a piggyback, I assume. I bought an FIC 6 for that purpose, but have not seen a real need for it yet. I installed a wideband sensor on each header.

I honestly think R9K can resolve your wide open throttle fueling issues. I no longer have issues here as he adjusted my air/fuel ratio and ignition timing. Both through trial and error but it's spot on now. The ECU manages around town driving with no issues with 450cc injectors.
 

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I honestly think R9K can resolve your wide open throttle fueling issues. I no longer have issues here as he adjusted my air/fuel ratio and ignition timing. Both through trial and error but it's spot on now. The ECU manages around town driving with no issues with 450cc injectors.
Thanks for the info... Maybe you wouldn't mind making an introduction if/when I get around to that? I need to install a boost gauge with logging output to get some accurate AFR / manifold pressure data. I would be more on top of this aspect of things, except it drives well with seemingly conservative AFR in boost, and the transmission is the glaring elephant in the room. I can use about 1/3 - 1/2 throttle for the 1-2 shift, but the 2-3 is so silly I basically let off the pedal and let it shift then step on it again. Downshifts are fine...seemingly no issues there.

Oh, I forgot to mention... and I doubt this is even related to kit installation: I have been getting a fuel evap system purge flow ECU error. I suppose it could be the gas cap, but the cap looks okay. Are there any quick areas to check for a fix?
 

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Discussion Starter #155
Thanks for the info... Maybe you wouldn't mind making an introduction if/when I get around to that? I need to install a boost gauge with logging output to get some accurate AFR / manifold pressure data. I would be more on top of this aspect of things, except it drives well with seemingly conservative AFR in boost, and the transmission is the glaring elephant in the room. I can use about 1/3 - 1/2 throttle for the 1-2 shift, but the 2-3 is so silly I basically let off the pedal and let it shift then step on it again. Downshifts are fine...seemingly no issues there.

Oh, I forgot to mention... and I doubt this is even related to kit installation: I have been getting a fuel evap system purge flow ECU error. I suppose it could be the gas cap, but the cap looks okay. Are there any quick areas to check for a fix?
Sorry to hear about your shifting issues. I had a shift kit installed before the supercharger and I guess I haven't given it enough credit. Since the Level 10 valve body modification didn't shift as hard as it did when done on my Subarus, I kinda felt it wasn't worth the money. It must be doing it's job. No problem with 1-2nd or 2nd to 3rd shifts. I know how bad the 2nd-3rd gear shifts can be in all my cars before modification. It just didn't seem like it had little if any effect when I had it done while N/A.

As for the purge flow ECU error, I did have it pop up once but it never came back again. So I never looked into it. I did check my gas cap after it came on the first time though.
 

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If i am looking into having my Rav4 tuned. Would you recommend a valve body upgrade in addition to a tune? How much do you feel the tune makes of a difference for a mildly modded V6 2012. Im finally ready to pull the trigger, just want to ensure the vehicle can handle the driving style and power.

Thanks,
JJ
 

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Discussion Starter #157
If i am looking into having my Rav4 tuned. Would you recommend a valve body upgrade in addition to a tune? How much do you feel the tune makes of a difference for a mildly modded V6 2012. Im finally ready to pull the trigger, just want to ensure the vehicle can handle the driving style and power.

Thanks,
JJ
Hard to say! I mean, I ran the 13.6 with the R9K tune. I couldn't get that before no matter what I did or how cold out it was. It didn't feel any faster but testing showed that it was. I couldn't argue with the results. I mean, with an intake, exhaust and tune it was running 13.6-13.7's. In an N/A SUV. Toyota...that ain't right man. >:D
 

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Is there any way to try a smaller pulley? I I’m reading that the kit isn’t worth it, but 7 psi seems a little mild. Isn’t this the same engine that runs 14 psi on the Evora? Just curious because I had a Saturn Ion Redline, and a smaller pulley made a big difference
 

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Is there any way to try a smaller pulley? I I’m reading that the kit isn’t worth it, but 7 psi seems a little mild. Isn’t this the same engine that runs 14 psi on the Evora?
Running high boost requires starting with or lowering the compression ratio to around 8:1. Otherwise you need to be driving around with super expensive and maybe emissions illegal race gas.
 
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