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Delta said they could weld my 1ZZ cams back in 2014, and they still advertise welding on their website, so idk. The price was pretty reasonable when I asked back then, I think it was 275 for weld + grind on one camshaft.
The material that works for a flat-tappet valvetrain does not work for a roller-follower valvetrain. A billet steel camshaft is totally incompatible with flat tappets, it doesn't matter what the steel strength is, the cam tips will gall and fail within hours. Roller tappets require high-strength steel cam lobes. Production flat tappet engines use a process called "chilled iron" casting where the cast iron camshaft mold has "chills" as part of the mold to create a quick hardening of the cam lobes, which forms carbide at the surface of the cam lobes. Flame-hardened cast-iron is a low-cost and less-durable alternative. If the shop knows what they are doing and use the correct weld-metal, they might be able to create an acceptable surface for a flat tappet. When you re-grind a chilled-iron cam, the objective is to not totally remove the thin layer of carbide (especially on the lobe tip) so you still have carbide running on the steel tappet. I know the above from my experience as a valvetrain engineer.

Dave
 

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The material that works for a flat-tappet valvetrain does not work for a roller-follower valvetrain. A billet steel camshaft is totally incompatible with flat tappets, it doesn't matter what the steel strength is, the cam tips will gall and fail within hours. Roller tappets require high-strength steel cam lobes. Production flat tappet engines use a process called "chilled iron" casting where the cast iron camshaft mold has "chills" as part of the mold to create a quick hardening of the cam lobes, which forms carbide at the surface of the cam lobes. Flame-hardened cast-iron is a low-cost and less-durable alternative. If the shop knows what they are doing and use the correct weld-metal, they might be able to create an acceptable surface for a flat tappet. When you re-grind a chilled-iron cam, the objective is to not totally remove the thin layer of carbide (especially on the lobe tip) so you still have carbide running on the steel tappet. I know the above from my experience as a valvetrain engineer.

Dave
The random things I didn’t even know that I didn’t know reading some threads never ceases to amaze me. Engineers...the guys that know exactly which devil is in which details
 
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The material that works for a flat-tappet valvetrain does not work for a roller-follower valvetrain. A billet steel camshaft is totally incompatible with flat tappets, it doesn't matter what the steel strength is, the cam tips will gall and fail within hours. Roller tappets require high-strength steel cam lobes.
Now I know, makes sense. I always kind of wondered in the back of my head what the limitations on regrinds were. I thought almost all OEM camshafts were cast iron for cost reasons.
 

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Now I know, makes sense. I always kind of wondered in the back of my head what the limitations on regrinds were. I thought almost all OEM camshafts were cast iron for cost reasons.
The two big differences between roller and sliding interface valvetrains are:
1) contact stress at the lobe tip; rollers are more than twice as high (mainly due to the radius of the follower), so you need a steel cam to avoid surface fatigue cracks and destruction
2) Tribology: when 2 lubricated surfaces are not separated by a hydrodynamic oil film, they are in boundary-lubrication and therefore there is some contact between the 2 surfaces. In these conditions, certain material combinations have terrible resistance to micro-welding. like hardened steel running on hardened steel. On a prototype engine we wiped out a steel cam on steel tappets in 10 minutes of running. Changed the material to chilled iron and it lasted forever. The carbide layer on a chilled iron cam is 1-2mm thick.

Dave
 

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Discussion Starter · #66 · (Edited)
The LSD came in today. Here is a comparison of the 2 differentials, left OEM and right Franavehicles.com custom LSD. Cleaning the gear and bolts. Toyota has a national backorder on tranny parts so let's see if the cams come before the parts. Hopefully FMW will be ready to tune the rav4 ecu at that time. Otherwise I'll get link fury to hurry the start up.
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I just remembered something: There are a lot of GR variants with compatible camshafts!

The 2GR-FXE definitely has significantly more duration, and maximum lift is around equal (that's the case on the other Toyota hybrids). IIRC there isn't much more lift you can get before coil bind, so that's not a big deal. If the duration is excessive, you would be able to grind the profile down to get something in between the stock FE and the FXE.

On the intake side, what I would expect is that the profile itself is fine but you might want to advance it a little as the hybrid engines run with the cam always closing later, and the VVT adjustment range is limited.

The nominal duration on the FE cam is 247 degrees:


On an old 1NZ-FXE prius engine, it looks like this:


Eyeballing it, that looks like around 268 ish.

The interesting thing is the same picture for the Tacoma's 2GR-FKS (tuned for better low end torque, weaker top end) says -33 BTDC to 105 ABDC = 252 degrees on the intake cam:

The Camry also running on 87 octane produces 301hp by comparison, which could just be a different intake, but I wouldn't be surprised if the cams were different.

Interestingly, the later RX450h and Highlander hybrid are rated at 308hp, just 3 less than the IS/GS350's 2GR-FKS. That could mean the cams are very similar, but timing is reduced on the hybrids due to the higher compression ratio.

My best guess is that the port injected RX450h and Highlander camshaft is somewhere around 270 degrees (the compression ratio is 12.5 vs 13 on the prius, but the wider bore has lower knock resistance, so VE is probably similar), and you may want to install it advanced 10 degrees to place peak lift at the same place. That said, both intake and exhaust could probably still be bigger if you want power over 8000rpm, so your Catcams pieces aren't a waste if base circle grinding is unacceptable.

 

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Discussion Starter · #68 ·
It's going to take me a few days to translate that info and research it. LoL I'm not going over 8000rpm. I have no engineering or mechanical help so to tackle the solid lifters and oil pump would be over my skillset. This past week I called 5 shops, 1 of which grinded down and installed my selector shaft on the 2zz. Not a single shop would work on my transmission and all I want them to do is pull the gears and press in the new ones. I'm buying a press and doing it myself which eats up my spare time. I'd rather buy a dog box before trying to go over 8000rpm anyway.
 

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I couldn't find a machine shop to clean/hot tank the internals of my transmission but I found two shops that would rebuild it. One is an old school transmission only shop with great reviews and good customer service, the other is a honda race shop who's race cars are top notch and who's shop work seems decent. I guess it is regional thing. I have a press but am not touching the transmission internals. Maybe the next one but I need this car to run preferrably with all 6 gears and no noise...

As for a dog box, be careful what you wish for, If you have driven them before and it is a purpose built race car then awesome. If you have any desire to drive it on the street run away. I have an old rally car with a dog box and 400hp. Even transit stages used to suck. Unless you are flat out it is really just a pita.My $.02.
 

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Discussion Starter · #70 ·
I couldn't find a machine shop to clean/hot tank the internals of my transmission but I found two shops that would rebuild it. One is an old school transmission only shop with great reviews and good customer service, the other is a honda race shop who's race cars are top notch and who's shop work seems decent. I guess it is regional thing. I have a press but am not touching the transmission internals. Maybe the next one but I need this car to run preferrably with all 6 gears and no noise...

As for a dog box, be careful what you wish for, If you have driven them before and it is a purpose built race car then awesome. If you have any desire to drive it on the street run away. I have an old rally car with a dog box and 400hp. Even transit stages used to suck. Unless you are flat out it is really just a pita.My $.02.
I've got until March 2021 before my warranty on my grocery getter expires. I'm going to trade it in for truck so I can trailer the mr2 to out of state tracks. The gearbox was shipped from Puerto Rico in who knows what kind of condition. So far it looks good but I'm going to replace the synchros, 6th, and bearings. If the gearbox blows I'll consider a dogbox but not until that. This will be a dedicated track car so I'm not going to complain about harshness.

I wish I had 2 choices for shops, I'd use both for different odd jobs. The tranny isn't really that hard to work on from what I've seen. Hopefully it'll all go well and I'll refresh the c60 2zz after I pull that out.
 

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Discussion Starter · #71 ·
Went to northern tool to pick up a press. Bearing separator and locking casters come in tomorrow.
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Discussion Starter · #72 ·
Casters worked out better than I thought.

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I used some decorative bricks from outside and old wood as press plates. Now I see why people get those k shaped plates.
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I heard a lot of pings and popping
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I uscrewed and adjusted, then pushed some more.
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I had to make sure it didn't drop but the bottom plate ended up getting in the way so I had to catch it with my other hand anyway.
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I don't condone this set up, its very dangerous. Now, on the the other side bearing. This MFer was a paint in the ass. I couldn't get the puller to clear the roller/cage, so in comes the dremel.
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I break open the cage/rollers and play the tense game of pop goes the weasel with the bearing. This time nothing would clear the differentials lip so I flipped the beams inside out. It worked in giving me the worst anxiety.
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I first tried pulling from the top lip but I chipped the bearing but got enough pulled to grab it from the bottom lip.

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Metal was flying all over the place as you can see from the damage.
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I'm going the cut the rollers/cage on the other bearing and use it as a press for the new bearings. It was a great learning experience since I've never done this before. Learning curve was a few hours for me to rig everything up. Those big k press plates, longer bolts to hold the base beam, more 2x4 will be needed to finish this comfortably.
 

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Discussion Starter · #73 ·
The 1.25in socket from my biker days worked out great. I'm going to toss the chipped bearing. I'll take off the cage/rollers and use the undamaged old bearing to press in the new ones.
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Since I'm now thinking about doing a 2GR (in an SW20 though, I just like how that car looks), and I thinking of doing pretty much exactly what you're doing, I wanted to ask what are you doing for tuning? Changing the compression ratio from 10 to 12 is going to need a very different ignition timing map, and I'm trying to think of the easiest way to accomplish that...
 

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Discussion Starter · #76 ·
Since I'm now thinking about doing a 2GR (in an SW20 though, I just like how that car looks), and I thinking of doing pretty much exactly what you're doing, I wanted to ask what are you doing for tuning? Changing the compression ratio from 10 to 12 is going to need a very different ignition timing map, and I'm trying to think of the easiest way to accomplish that...
I'm going to have a custom tune by Frankensteinmotorworks. 550cc injectors OEM ecu reflash.
 

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Discussion Starter · #79 ·
had to improvise to get the pre load on the LSD so I came up with this solution. Used a head stud and 2 bolts to lock it into the center of the LSD
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