1GR-FE (Single VVTi) Dyno Testing by OTT

I am curious about the effects of running a 170 degree thermostat.

 

On power? None.

 

Just did this to my 1GR, love it! .. I can shift 1st to 2nd more efficiently and stay in power, the torque is noticeably fatter, the steep hills had to downshift to 5th, now 6th gear no problem (RC62 trans) .. worth every penny

 

Just did what to your 1GR?

 

Got tuned...

 

Thanks for this post and all your tests, sharing/analysis and data Justin! Very educational.

So far for a Taco 2014, what is your takeaway (besides your comment about doing a proper and regular maintenance)?

CAI? Spark plug? exhaust? etc...

I will definitely consider a Tune but no OTT near by my place :/

 

I still stand behind my statement that maintenance should be first and foremost before a tune. I say that even being in the business of selling calibrations. I'd prefer to tune 1 properly maintained vehicle than 2 poorly maintained ones. I'm less likely to have a customer with less than stellar performance due to the vehicle not working as intended, not to mention there will be far fewer issues I have to deal with from a customer thinking the tune will fix or mask the poor maintenance and issues associated with the lack of maintenance.

I'd like to remind everyone here who may be following along. None of these modifications alone will turn this motor into a "monster". Each of these modifications is worth a few horsepower, and its the sum of these small improvements that will wake the truck up. If you go down the bolt on modification path thinking each one will knock your socks off, you will be disappointed. You see it all over the forum: "This mod doesn't do anything". Five-wheel horsepower on a 4600+lb vehicle isn't going to change the power-to-weight ratio enough to have a perceivable change in the rate of acceleration/put-you-in-the-seat performance.

But some simple mods to improve the performance of the Single VVTi 1GR would be (in no particular order):

1. Intake, something drawing air from outside the engine bay.
   
2. 70mm OEM 5th Gen 4Runner Throttle Body (for N/A setups, or mild boosted applications)
   
3. Intake Manifold Spacer (not a throttle body spacer)
4. 3° Retarded Exhaust Cam Gears
   
5. ECU Reflash/Tune
   
6. Run "Premium" grade fuel.

Exhaust is a tricky one. My testing shows the restriction is primarily the manifolds, then Y-pipe, with the cat-back being the least restrictive part of the exhaust for a N/A vehicle. The problem is there are legal implications with replacing the manifolds. The URD Spec-U headers are the best performing header I've tested but they remove the primary catalysts and I just cannot recommend doing that on a street vehicle. An alternative that might be worth looking into is the aFe Twisted Steel Header. I understand they had problems in the past with cats being blown out mostly on forced induction vehicles, but they've since upgraded their catalysts to high quality GESI cats.

For the calibration, we offer remote calibration services where we can supply you all the hardware/software you need so you can tune it yourself in your driveway. If you aren't near one of our retailers we'd be happy to help you out. Send us an email to let us know how we can help. info@overlandtailor.com

 

Thanks Justin.

For the exhaust, there is also the "comfort" if the truck is a daily drive.

I will keep the email and probably ping you back in September.

 

Hi
Is there dyno test result for the 3 degree cam retard ?
thanks

 

We have them in inventory, and in the que to test. But at this time we do not have results for them.

 

Following.

 

I would love to see a dyno for 3rd gen V6 with aes spacer plus the tune.

 

Send AES and email and tell them you'd like to see OTT test their spacer - OTT will make it happen.

 

Is it me or the cam gears are useless if you have a tune ? You could dial exactly the 3 degres offset they offer anywhere in the tune, no ?

 

Nope, the exhaust side of the head does not have variable valve timing only intake. At least on the Tacomas. Some 4runners have dual VVTI and I don't think anyone cam gears those.

Therefore, cam gears are the only way to retard exhaust timing on a Tacoma 1GRFE

 

Definitely not useless if you do not have a tune. I ran mine for almost a year before I got a tune.

Well worth the effort.