Prius Pistons

[Viperoni]

Here's another thought; since 13:1 *may* be on the high side... are there thicker head gaskets we can use?

[JustDidIt]

Originally Posted by JustDidIt

I've found a FULL 2012 Yaris 1NZ-FE cylinder head super cheap. Now just waiting to hear back if I can have it shipped or if I have to go pick it up.

For a decent EMS...Still haven't found much info on whether or not I can get by with the AEM F/IC or if I'll have to step all the way into the AEM EMS2 $$$$ :( Tuning is my biggest concern at this point. Just not looking to drop $2k just yet on EMS.

[xnamerxx]

Here is a comment from someone I know who used to tune cars for AEM, about using it for tuning my car.

the FIC was good, but i only used it on FI apps. in FI apps we only retard the timing, in your case i would imagine you want to increase the timing, which it cant do, can't predict the future, only delay it

[JustDidIt]

Originally Posted by xnamerxx

Here is a comment from someone I know who used to tune cars for AEM, about using it for tuning my car.

The FIC was good, but i only used it on FI apps. in FI apps we only retard the timing, in your case i would imagine you want to increase the timing, which it cant do, can't predict the future, only delay it.

I would probably just need to adjust the timing and A/F ratio - if you moved the timing chain up a bit manually with a AEM F/IC you could retard the timing to adjust according while adjusting the A/F ratio to compensate for the OEM tune (as you mentioned..can't increase timing with the AEM F/IC only retard)

[BEEF]

I am not sure if garm commented earlier in this thread but you can get pistons from him in a variety of thicknesses (compression ratios) so the big reason to use the prius pistons would be to save money.

I can't remember exactly what he said he had but it seems like he had 9:1, 11:1 and a 12:1. I may be a bit off on that one but you could ask him directly.

[JustDidIt]

Originally Posted by BEEF

I am not sure if garm commented earlier in this thread but you can get pistons from him in a variety of thicknesses (compression ratios) so the big reason to use the prius pistons would be to save money.

I can't remember exactly what he said he had but it seems like he had 9:1, 11:1 and a 12:1. I may be a bit off on that one but you could ask him directly.

Saving $$$ is the idea... otherwise your correct you can get Arias Pistons with the CR ratios of 9:1 - 14:1 for the 1NZ...

Basically I just need the Cams and Cam gear with EMS...and I can test out this "prius Pistons" theory - not only will I get a bump from swapping cams from 1NZ-FXE to 1NZ-FE (stock 78hp to 108hp) ..but I should get a small boost from the 10:5 to 11:1 CR increase. I am sourcing a full 1NZ head now.

[cali yaris]

^ Or CP pistons, or a couple of other brands. All available in whatever size/compression ratio you want. I wouldn't pay the premium just for the Arias name, but that's up to each customer; they do make great products.

[cali yaris]

I don't see any baffling in the large picture that xnamerx posted. The inside of the cutout intake manifold is shown in blue, right? Looks pretty smooth and open.

What's the purpose of a different manifold?

off-topic. How difficult would it be to transplant my motor/trans into a Prius?

[JustDidIt]

Originally Posted by cali yaris

I don't see any baffling in the large picture that xnamerx posted. The inside of the cutout intake manifold is shown in blue, right? Looks pretty smooth and open.

What's the purpose of a different manifold?

off-topic. How difficult would it be to transplant my motor/trans into a Prius?

Haven't ever really looked inside mine but I doubt its as smooth. I'm sure this one was polished up and powder-coated for display.

The 1NZ-FXE manifold was tuned for for a specific RPM range with most efficient MPG... I'm not concerned about MPG but more looking to increase HP. Most N/A motors w/o going ITBs have longer intake runners - not like the Prius's 1NZ-FXE manifold.

Are you speaking of your 1NZ-FE? The Motor transplant shouldn't be difficult and was done by the Bonneville Landspeed Prius. They swapped the Otto Cycle 1NZ-FE from an Toyota Echo in but didn't do the Prius pistons swap. I'm looking to do both. Besides the MG1/MG2 and tranny the engine itself (mounting points) are exactly the same as the 1NZ-FXE

Transmission transplant - hmm...depends on if you want to keep the hybrid system or not.

[xnamerxx]

Originally Posted by cali yaris

I don't see any baffling in the large picture that xnamerx posted. The inside of the cutout intake manifold is shown in blue, right? Looks pretty smooth and open.

What's the purpose of a different manifold?

off-topic. How difficult would it be to transplant my motor/trans into a Prius?

Atkinson cycle engines don't have large powerbands but rather a small efficiency zone, so whereas a traditional otto engine is probably about 27-33% efficient between 2-5.5k a Atkinson engine is 35-39% efficient between 4-4.5 rpms. So because it uses a hybrid drive transmission the engine never really cycles through its rpm range but rather like a CVT just has a gearing change that keeps the engine happy but still allows acceleration while the electric engine is providing the majority of the mechanical drive.

I don't think the transmission bolts up to the 1nz-fxe, it would be far simpler to get an electric engine/generator and attach it to the crank snout like a supercharger to get some extra assist that way. That kinda the way honda currently does it with the CRZ/Insite

[JustDidIt]

Originally Posted by xnamerxx

Atkinson cycle engines don't have large powerbands but rather a small efficiency zone, so whereas a traditional otto engine is probably about 27-33% efficient between 2-5.5k a Atkinson engine is 35-39% efficient between 4-4.5 rpms. So because it uses a hybrid drive transmission the engine never really cycles through its rpm range but rather like a CVT just has a gearing change that keeps the engine happy but still allows acceleration while the electric engine is providing the majority of the mechanical drive

I don't 'feel' my Prius engine at all under 3000k but the usable rpm looks to be about 3000-5500. Swapping the cams yet keeping my pistons will essentially switch me over to otto cycle with a touch of compression increase.

[xnamerxx]

I can almost guarantee you, you'd be doing more harm then good by swapping to otto cycle cams in your engine. The prius is mainly powered by the electric engine, so to make that as efficient as possible the torque output on the gas engine needs remain a constant. The numbers I listed were WAG and so probably not accurate. Remember your gas engine isn't directly connected to the wheels, so its RPM's are also not a contant

Here is a website that explains how the HSD powersplit device works. Website

Upping the power on the gas engine doesn't help as much as you'd think since only torque at certain rpms provides assist. Since the engine only revs to 5k you'll be throwing away all the constant torque of the fxe to gain the peak torque of the fe all with major loss and no benefits. You have to think of the gas engine as a electricity generator/backup power unit rather than a PU. You can rev the nuts off the Prius engine and the car won't move unless the electric motor is moving.

[JustDidIt]

Originally Posted by xnamerxx

I can almost guarantee you, you'd be doing more harm then good by swapping to otto cycle cams in your engine. The prius is mainly powered by the electric engine, so to make that as efficient as possible the torque output on the gas engine needs remain a constant. The numbers I listed were WAG and so probably not accurate. Remember your gas engine isn't directly connected to the wheels, so its RPM's are also not a contant

Here is a website that explains how the HSD powersplit device works. Website

Upping the power on the gas engine doesn't help as much as you'd think since only torque at certain rpms provides assist. Since the engine only revs to 5k you'll be throwing away all the constant torque of the fxe to gain the peak torque of the fe all with major loss and no benefits. You have to think of the gas engine as a electricity generator/backup power unit rather than a PU. You can rev the nuts off the Prius engine and the car won't move unless the electric motor is moving.

TRD did it... with the Otto swap..

Originally Posted by JustDidIt

.....Motor transplant shouldn't be difficult and was done by the Bonneville Landspeed Prius. They swapped the Otto Cycle 1NZ-FE from an Toyota Echo in but didn't do the Prius pistons swap. I'm looking to do both.

Originally Posted by xnamerxx

You can rev the nuts off the Prius engine and the car won't move unless the electric motor is moving.

Not completely true...when the battery doesn't have enough juice to run the MG2, u can feel ONLY the gas engine struggling to push/pull the car along. With the battery charged enough from the regenerative braking from MG1, MG2 kicks in to assist the gas motor also boosting the inverter from 220v up to 500v.

[jetblast]

Now if someone just rips open a Prius and magically finds Carillo, Pauter, or even Molnar rods attached to these pistons. In that case, key up the Mission Impossible theme music as I put on the black spandex from my early spy days. Into the local junkyard all night long to harvest the jewels.....hey, this spandex used to fit.

C'mon! I can dream!!!!!!

[cali yaris]

justdidit, were you looking for a head?

[JustDidIt]

Originally Posted by cali yaris

justdidit, were you looking for a head?

Technically still need one. Found a awesome deal on a 2012 1NZ-FE but I haven't heard back if they will ship it to me or if I need to drive up to the LA area to pick it up. Not so much ur neck of the 'woods' but more east LA. Either way I am still needing one.

[Viperoni]

Don't know if it's in here, but this site sells Toyota OEM Prius pistons for $51 a piece:
http://www.trademotion.com/parts/200...mponent=PISTON