Tomei 260 Poncams - Not so small?

[Canadian_CD9A]

I just did a little reading into the Tomei 260* Poncams I have for my Evo 1. They're looked over almost entirely and the price is very reasonable, so I bought them just to have a nice mild cam. I'm slightly confused though...for a 260* cam, these things seem big - bigger than most 264s. The closest thing I can find is the Kelford TX264 and FP2:

Kelford Lift: 11.00/10.35
Kelford Duration @ 1mm: 216/216

HKS Lift: 10.80/10.20
HKS Duration @ 0.050": 214/214

Tomei Lift: 10.70/10.20
Tomei Duration @ 1mm: 215.5/214.5
Tomei Duration @ 0.050": 209/209

So am I right to be thinking that my "puny" Tomei 260s are really going to perform like HKS 272s or Kelford TX264s?

 

[bastarddsm]

Where did you get those numbers for the HKS I thought they were 10mm and 10mm on the dsm ones, the duration seems kinda big too, but i haven't looks at it in a while.

The TX264 numbers look big too. but maybe I'm crazy .

 

[Canadian_CD9A]

Tomei: https://www.tomeiusa.com/cam_spec/4g63/4G63-260-10.7_10.2_evo1-8LE.pdf
Kelford: http://www.maperformance.com/kelford-cams-1-tx264-camshaft-mitsubishi-4g63-vr4-evo-1-3.html

You're right on the 272s, I was looking at later Evo specs.

HKS 272 Lift: 10.30/9.80
HKS 272 Duration @ 0.050": 195/195

Source:
http://www.columbusdsm.com/forum/showthread.php?t=6876

GSC measures their cams at 0.040" so we can't compare. Kelford and Tomei's lift figures are calculated with a 1.73 rocker; HKS uses 1.7, so I don't know how to equalize the DSM numbers to compare.

 

[Canadian_CD9A]

Tomeis are apparently bigger than BC 272s as well, looks like it fits in well with the 272s.

BC 272 Lift: 10.18/9.66
BC 272 Duration @ 0.050": 208/212

BC 280 Lift: 10.71/10.60
BC 280 Duration @ 0.050": 218/216

BC 288 Lift: 10.80/10.57
BC 288 Duration @ 0.050": 218/216

Comp 101100 Lift: 10.34/9.93
Comp 101100 Duration @ 0.050": 204/204

Comp 101200 Lift: 10.44/10.03
Comp 101200 Duration @ 0.050": 212/212

Comp 101400 Lift: 10.54/10.13
Comp 101400 Duration @ 0.050": 220/220

Jun 272 Lift: 10.62/10.62
Jun 272 Duration @ 0.050": 211.5/211.5

Tomei Procam 270 Lift: 11.50/11.50
Tomei Procam 270 Duration @ 0.050": 221.0/220.5

Tomei Procam 280 Lift: 11.50/11.50
Tomei Procam 280 Duration @ 0.050": 228/227

***BC is also measured with a 1.7 rocker
Still, Tomeis are just monster cams unless I'm making a mistake somewhere. The 270 is similar to the Kelford 272 on duration but way higher on lift, while the 280 lines up pretty squarely with Kelford's 280.

If measured with a 1.7 rocker like some of the others, the Tomei 260 becomes:

Tomei 260 Lift: 10.49/10.00
Tomei 260 Duration @ 0.050": 209/209

Still right in 272 land...

 

[bastarddsm]

Whole thing about this is I really don't know how much it helps over-all. Sure if your running a gt35 at 20psi, going from stock cams to k272's is going to net some gains, but if you are running a 16g maxed out I doubt you'll see anything.

The one guy making 600 on an hx35 with stock cams, thats just about the most ever on that turbo. Then back in the old days guys ran 8's on HKS272's with t61-O trims.

It does look like the tomei's are pretty big. The best thing to do to compare them is put them in a head with a test spring and a solid lifter and measure the lift at every degree. Then you can compare what the lift curve really looks like. What cams have the "port - time - area", and are the gentilist to the valve train. Thats what's important.