Camshafts

[Mattmahope 225]

@IanA you are right that the Kelford cams are aimed at turbo builds. Not ideal but definitely an improvement on NA cams. Kelford can also custom build whatever cams you want but of course the real time/effort goes into the design and testing to make sure they work perfectly in practice.

That’s why I am currently working with Komotec to develop cams for my build. They are working with a top, top tier OEM supplier (think Veyron tier...) to design, build and test best options. Komotec are doing something similar with other equivalent suppliers for rods, pistons and valves. They have just released the new pistons:

The other parts are still in development and testing. The rods will be very similar X-beam design to the ones they have already released for the 2ZR:

(Afraid the videos are in German - not sure how good you language skills are!)

I am absolutely convinced that cams designed specifically for a supercharged application will make a considerable difference to both power and efficiency of the engine, especially if combined with all the other upgraded parts for a fully built engine that is designed to work together as a package. Still a bit of a pipe dream, but would be amazing if it all comes together. Daniel seems very enthusiastic about the project and the development work is very exciting. Fingers crossed!

[Mattmahope 225]

Also note that Komotec are are now offering proper cylinder head work as well:

https://www.komo-tec.com/en/lotus-exige/mk3-toyota-v6350380/engine-components/731/cylinder-head-modification-phase-1-v6-2gr?c=914

[ILLATOUCH 6]

On 16/01/2021 at 04:50, Mattmahope said:

@ILLATOUCHis your 2GR in NA form or supercharged? CatCams definitely look good for NA but not really right for supercharged applications.

my 2gr is NA.  Catcams uses stock retainers and pac springs. I'm using Lexus ISF titanium intake valves and did a minor port/polish on the head/lower intake manifold. I'm doing it in a spyder w/eb60 gearbox, so no way I can fit a supercharger. EFR 7170 would fit. 

Edited January 21 by ILLATOUCH

[Mattmahope 225]

Wow, what a fantastic build! Thank you for sharing the pictures.

What rpm are you looking to hit and what spring rates are you using for that?

How much does each ISF titanium valve weight? I have also been considering those as a solution. Did you buy them from MWR or elsewhere?

[ILLATOUCH 6]

21 hours ago, Mattmahope said:

Wow, what a fantastic build! Thank you for sharing the pictures.

What rpm are you looking to hit and what spring rates are you using for that?

How much does each ISF titanium valve weight? I have also been considering those as a solution. Did you buy them from MWR or elsewhere?

Thanks! I hope to have it finished soon. I'm hoping to have it with working a/c too.

Max 8k rpm but I'll most likely keep it under 7500, 99% of the time. This is what the engineer said about the springs, "With this camshaft i would say that the rpm range will be 3500-4000 rpm to 7500-8000 rpm. With the springs the limit is 8000 rpm we also have gold springs pac-s10015 same specs but for higher rpms so 8000rpm and up."

Not sure about the weight, I think 30grams. They're Lexus part #13711-38050 about $14 each. Catcams said I didn't need titanium retainers so all the OEM 2gr stuff works, IE keepers, seats, retainers, etc. 

I went with the cheapest online vendor, oemvehicleparts.com for the lexus parts and mcgeorge toyota for the OEM toyota stuff.  I buy only a few things here and there from MWR. 

I'm looking for denso 550cc injectors for the 2gr at the moment. 

[IanA 12]

Good to see Komo-tec are developing SC cams for the 2GR-FE.

Have followed developments of this supercharged engine in Lotus cars and is the missing piece to gaining improved performance.

However hope that they are considering profiles as a drop-in performance upgrade for standard engines as well as profiles for built engines, as going too far would require changes to engine management and many would not want to go that far. I think the larger market for such would be prepared to invest in improved induction and a free flowing exhaust manifold to gain the performance benefit, but may not want to go further than that.

Even mild cams designed for SC application would use a lot more the present charge that is lost out the exhaust with too much overlap on the standard n/a cams.

Edited Friday at 09:24 by IanA
More info

[electro_boy 209]

@ILLATOUCH great work, please keep us updated with progress, I find this stuff really interesting but am total newbie hopefully some time in the future I'll have the knowledge to give something like this a go.

 

1 hour ago, IanA said:

However hope that they are considering profiles as a drop-in performance upgrade for standard engines as well as profiles for built engines, as going too far would require changes to engine management and many would not want to go that far.

@IanA I believe Komo-tec can reprogram the Lotus ECU, they don't require an aftermarket unit installed.  So while it would still be an extra expense to get a new tune it wont be as expensive or difficult to add a aftermarket ECU.  I would think anyone going for new camshafts would probably be prepared to get a optimised tune as well.

[ILLATOUCH 6]

3 hours ago, electro_boy said:

@ILLATOUCH great work, please keep us updated with progress, I find this stuff really interesting but am total newbie hopefully some time in the future I'll have the knowledge to give something like this a go.

 

@IanA I believe Komo-tec can reprogram the Lotus ECU, they don't require an aftermarket unit installed.  So while it would still be an extra expense to get a new tune it wont be as expensive or difficult to add a aftermarket ECU.  I would think anyone going for new camshafts would probably be prepared to get a optimised tune as well.

I was never interested in working on cars until I blew the 1st motor. These motors are pretty easy to work on if you have the shop manual and have the right tools. I learned all this stuff from google and online forums. 

 

I'm going to probably run with a reflashed ecu with the billet cams to break it in.  Frankensteinmotorworks can reflash toyota ecu's to run different set ups.  If not, I'm going to use a Link G4 Fury X. 

[Mattmahope 225]

@ILLATOUCHI think that your definition of "pretty easy" is very different to mine!  I think I'll be leaving my engine build to the experts, but I wish I had your skills, that's for sure.

I hope to be able to achieve a 8k redline like you, although I would also limit to 7600rpm most of the time.  Interesting that you have been advised that it is possible to run above 8000rpm just with stiffer springs.  Would you not expect the hydraulic lifters to fail at that engine speed?  I understand that the lifters are the limiting factor when it comes to revs on these engines, because at around 8000rpm they no longer lift fast enough and it spits the rockers.  How will you avoid that?

Are you using OEM exhaust valves?  Were you not tempted by the MWR inconel exhaust valves? Perhaps less relevant for an NA build I guess.

Not tempted by titanium retainers to save a bit more weight?

@IanA as @electro_boy says, Komotec can remap the standard OEM ecu, so I think that they would offer that alongside any new cams.  I think their intention is that whatever cams they finally settle on would be able to work in any supercharged build, not just the more extreme fully built motors.  I agree that there would be more demand for cams without having a fully build engine.  Komotec carbon air intake, full exhaust, better cams, lighter valves with stiffer springs, and a matching ecu tune would be one hell of a specification!

That is basically what I am aiming for myself, but also with forged internals to make sure that the engine can cope with the extra power from the TVS1900 supercharger that I have.

[ILLATOUCH 6]

9 hours ago, Mattmahope said:

@ILLATOUCHI think that your definition of "pretty easy" is very different to mine!  I think I'll be leaving my engine build to the experts, but I wish I had your skills, that's for sure.

I hope to be able to achieve a 8k redline like you, although I would also limit to 7600rpm most of the time.  Interesting that you have been advised that it is possible to run above 8000rpm just with stiffer springs.  Would you not expect the hydraulic lifters to fail at that engine speed?  I understand that the lifters are the limiting factor when it comes to revs on these engines, because at around 8000rpm they no longer lift fast enough and it spits the rockers.  How will you avoid that?

Are you using OEM exhaust valves?  Were you not tempted by the MWR inconel exhaust valves? Perhaps less relevant for an NA build I guess.

Not tempted by titanium retainers to save a bit more weight?

Another 2gr mr2 owner has had an 8k rpm motor for a while now with no problems.  I don't think I'll be spitting rockers so we will see.

I'm using new OEM exhaust valves only bc I didn't find a cost effective alternative. 

[ILLATOUCH 6]

It won't allow me to upload anymore pictures. Max total size.  I just received the billet cams today, I'd show some pics but I'm being blocked from doing so. 

[Bravo73 1,299]

7 hours ago, ILLATOUCH said:

It won't allow me to upload anymore pictures.

You’ve probably hit your upload limit for a Basic account. You can either upgrade to Full Forum membership (if you fancy hanging around) or host your images with a 3rd party and link to them from here. 

[Mattmahope 225]

@ILLATOUCHdid you consider titanium retainers at all?

Looking forward to seeing the cams!

[ILLATOUCH 6]

6 hours ago, Mattmahope said:

@ILLATOUCHdid you consider titanium retainers at all?

Looking forward to seeing the cams!

https://www.spyderchat.com/threads/2gr-swap-project.155731/page-4#post-2145763

 

You can see my build thread there. Im close to having all the necessary parts. All the unobtainium made parts are in my hands. I just need to fab the exhaust,  access panel, and axle carrier. I hope there would be an ac bracket prototype by then. Frankenstienmotorworks makes most of the swap parts. 

[ILLATOUCH 6]

6 hours ago, Mattmahope said:

@ILLATOUCHdid you consider titanium retainers at all?

Looking forward to seeing the cams!

I considered them but I was told they wear fast and they weren't needed.