Camshaft selection for a 1000hp RB26/30.

[SimonR32]

1 hour ago, Lithium said:

Interesting, same as the 9.25mm lift 264s - so to confirm, they are definitely 260 advertised duration?

Yup, there was talk about going a 222/222 and that was actually going to push the advertised duration to 226 but drop the lift down to 10mm

From Kelford

 

Quote

I personally would run the 226° ones, given their slightly shorter adv. duration (it’s a design and acceleration thing that makes this the case)

 

Edited June 28, 2017 by SimonR32

[Lithium]

How is idle etc?   The delivery really looks quite good

[SimonR32]

8 hours ago, Lithium said:

How is idle etc?   The delivery really looks quite good

Smooth idle, not even lumpy at all... I'll get a video on weekend

[burn4005]

hmm interesting.

is that 10.3mm lift the Net valve lift or the lobe height? (ie including the .25/.30 cold lifter clearance)

Edited July 5, 2017 by burn4005

[etang789]

I’m in the same boat as well cannot decide between Tomei or Kelford. Will be using
Borg Warner EFR 8374 1.05a/r and NITTO's 2.8Ltr Stroker Kit. Car will be mostly street so looking for response.

Looking at these:
Tomei Procam 260Degree 10.8mm Lift
Tomei Procam 270Degree 10.8mm Lift

Kelford 182-S 274/270 10.55mm&10.50mm/10.50mm lift.

Kelford 182-C 272/272 10.00mm/9.95mm lift

 

But don’t quite understand how to compare the numbers dunces ones advertised ones vs actual...

Edited November 4, 2018 by etang789

[Ben C34]

35 minutes ago, etang789 said:

I’m in the same boat as well cannot decide between Tomei or Kelford. Will be using
Borg Warner EFR 8374 1.05a/r and NITTO's 2.8Ltr Stroker Kit. Car will be mostly street so looking for response.

Looking at these:
Tomei Procam 260Degree 10.8mm Lift
Tomei Procam 270Degree 10.8mm Lift

Kelford 182-S 274/270 10.55mm&10.50mm/10.50mm lift.

Kelfors 182-C 272/272 10.00mm/9.95mm lift

 

But don’t quite understand how to compare the numbers dunces ones advertised ones actual...

They are both advertised duration.

I would think at this stage more development has been done by kelford than tomei.

[etang789]

12 minutes ago, Ben C34 said:

They are both advertised duration.

I would think at this stage more development has been done by kelford than tomei.

On their website they haven’t showed anything new thou. Emailed them about that 182-X 260 custom cam

[Meathead]

16 hours ago, Ben C34 said:

They are both advertised duration.

I would think at this stage more development has been done by kelford than tomei.

"cough"

[burn4005]

Let's rephrase that to more development in the last 15 years. Tomei are of the vintage of t51 and t04e turbos and old heavy dual valve springs . The world has moved on and cars are now running ethanol, single beehives and extremely efficient turbos. I'm not saying kelford has changed the game but things like the split lobe 274s would likely suit the modern engine better.

[Meathead]

5 minutes ago, burn4005 said:

Let's rephrase that to more development in the last 15 years. Tomei are of the vintage of t51 and t04e turbos and old heavy dual valve springs . The world has moved on and cars are now running ethanol, single beehives and extremely efficient turbos. I'm not saying kelford has changed the game but things like the split lobe 274s would likely suit the modern engine better.

Do you have the beehives on your setup?  you must be rich.  Tomei A work on pro 270 10.8 just fine. Not over sprung and kind to the running gear.

 

[burn4005]

yea they would be, but if you want a more agressive cam ramp they won't do the job. duration and lift doesn't tell the full story about cam design. there is another metric of the cam that is the average lift over the duration that tells more of the story about the cam profile.

also, worth noting the Tomei cams quote the lobe height and kelford quote the net lift. so they're both a 10.8mm lobe cam.

Edited November 5, 2018 by burn4005

[Meathead]

2 hours ago, burn4005 said:

yea they would be, but if you want a more agressive cam ramp they won't do the job. duration and lift doesn't tell the full story about cam design. there is another metric of the cam that is the average lift over the duration that tells more of the story about the cam profile.

also, worth noting the Tomei cams quote the lobe height and kelford quote the net lift. so they're both a 10.8mm lobe cam.

Both Tomei and Kelford quote net lift(Kelford)  and valve lift (Tomei) which is the same thing mate. ie Cam lift - clearance

Unfortunately no one quotes you the area under the mountain which is "secret" , unless you buy me the Kelford cam and i will measure it and tell you as I already have the Tomei and a few more.

26_260_1025_32_33.pdf                          

182-X 260 10.25mm.pdf  

Edited November 5, 2018 by Meathead
incomplete

[SimonR32]

On 11/5/2018 at 3:10 PM, Meathead said:

Both Tomei and Kelford quote net lift(Kelford)  and valve lift (Tomei) which is the same thing mate. ie Cam lift - clearance

Unfortunately no one quotes you the area under the mountain which is "secret" , unless you buy me the Kelford cam and i will measure it and tell you as I already have the Tomei and a few more.

26_260_1025_32_33.pdf                          

182-X 260 10.25mm.pdf  

Those 182-X are the custom ones that were made for me. @Piggaz check the sheet

Edited November 7, 2018 by SimonR32

[Meathead]

44 minutes ago, SimonR32 said:

Those 182-X are the custom ones that were made for me. @Piggaz check the sheet

How they working for you?

I asked for a custom 260 and that's what they offered...still not sure.

[SimonR32]

24 minutes ago, Meathead said:

How they working for you?

I asked for a custom 260 and that's what they offered...still not sure.

Out of the 5 sets of cams I've tried they are equal best response. 

On moderate boost levels they make the most power (but head is also now slightly ported), on high boost they make the most power (once again head is ported now).

Never apples with apples, but if I did it all over again, I'd be sticking with them

[Meathead]

25 minutes ago, SimonR32 said:

Out of the 5 sets of cams I've tried they are equal best response. 

On moderate boost levels they make the most power (but head is also now slightly ported), on high boost they make the most power (once again head is ported now).

Never apples with apples, but if I did it all over again, I'd be sticking with them

Interesting!   I remember reading you tried the staggered inlet cam 182s?  

Is the one you have now the first 260 you have tried and are you running suggested CLs?

Trying to wake my EFR up a bit earlier (260/10.25 Procams)  and tossing up between 182x or some 256 Reimax cams.

Which other cams did you try before if you do not mind me asking?

  

Edited November 7, 2018 by Meathead

[SimonR32]

21 minutes ago, Meathead said:

Interesting!   I remember reading you tried the staggered inlet cam 182s?  

Is the one you have now the first 260 you have tried and are you running suggested CLs?

Trying to wake my EFR up a bit earlier (260/10.25 Procams)  and tossing up between 182x or some 256 Reimax cams.

Which other cams did you try before if you do not mind me asking?

  

Staggered inlet were too big for my application (Precision 6262)

We started at centerlines they suggested, inlet got advanced a fair bit on the dyno. Exhaust stayed the same

Which EFR?

Grex unknown exact specs but around 9.1 260 or 264, Tomei Poncam Type B 260, Tomei Poncam Type R 250 and the Kelford 182-S

[Meathead]

29 minutes ago, SimonR32 said:

Staggered inlet were too big for my application (Precision 6262)

We started at centerlines they suggested, inlet got advanced a fair bit on the dyno. Exhaust stayed the same

Which EFR?

Grex unknown exact specs but around 9.1 260 or 264, Tomei Poncam Type B 260, Tomei Poncam Type R 250 and the Kelford 182-S

Thanks for the info, always good to know.  

I have the  8374 iwg, no E85 in Japan. Going to see how far my tuner can go with advancing the inlet next and other way on the exhaust.

If no joy will consider the 182x or some Reimax group A cams (264/9.7) or their street cam (264in 256exh), they run 105 CLs all around with quite a bit of overlap, have good reports over here for coming on well.

What size HG you have 1.0mm?