# cam timing suggestions for 272



## unknowable (Apr 10, 2011)

Ive looked around, and im trying to find out what the optimal performance timing setup would be for a TT272 cam.

I saw someone suggest 0* for a 270. But ive seen other suggestions for a 276. Not many out there for a 272.

Any opinions based on experience??


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## Jay-Bee (Sep 22, 2007)

Test it at 0, advanced and retarded and drive it a bit on each one, set it how you like it.


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## unknowable (Apr 10, 2011)

okayyyy. i guess i was also just trying to figure out if I should buy an adjustable cam gear. Looks like Ill go for it and give her a shot. Thanks.


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## Jay-Bee (Sep 22, 2007)

I thought you had a cam gear already.


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## Glegor (Mar 31, 2008)

unknowable said:


> Ive looked around, and im trying to find out what the optimal performance timing setup would be for a TT272 cam.
> 
> I saw someone suggest 0* for a 270. But ive seen other suggestions for a 276. Not many out there for a 272.
> 
> Any opinions based on experience??


dont waste the hundred dollars.. the affects of an adjustable sprocket are very slim with a little cam..


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## tdogg74 (Mar 1, 2002)

Glegor said:


> dont waste the hundred dollars.. the affects of an adjustable sprocket are very slim with a little cam..


 

A stock cam, not much difference. But since when is a 272* cam "little? :screwy:

OP, you're gonna get about 3-5wtq gain (advancing 4*) and about 3-5wtq loss (retarded) on your low end up till you peak whp. After that, depending on the timing you set, your torque will either hold out longer (retarded) after peak, or die off quicker (advanced).


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## Glegor (Mar 31, 2008)

tdogg74 said:


> A stock cam, not much difference. But since when is a 272* cam "little? :screwy:
> 
> OP, you're gonna get about 3-5wtq gain (advancing 4*) and about 3-5wtq loss (retarded) on your low end up till you peak whp. After that, depending on the timing you set, your torque will either hold out longer (retarded) after peak, or die off quicker (advanced).


anything streetable, is fairly small to me.. (basically anything under a 288*)

when it starts running like a honda on the road, then its got a bigger cam.. sure, lots of people run a 288* on the road, but they are less than ideal.

sorry, but i guess my idea of "little cam" must be different from yours..

had a 268* neuspeed cam in my last GTI, it was little, but it made the car come alive, and ran best when it was zero'd out..


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## tdogg74 (Mar 1, 2002)

256-260 is little. 
266-272 I would consider a fast-road cam and what 80% of the VW population gets/runs. 
276 is where its at.
288 is a waste in a MKIII in full street trim and a stock CHE/DFQ trans. 
Anything above those are a pain in the ass to drive.


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## unknowable (Apr 10, 2011)

**

Yeah, after thinking a while, I still figured it would be nice to have more control over my power band with and adjustable cam sprocket.

I had stuck with a 272* because this is a daily driver, and havent got around to porting my head yet. 

Is there really that big a difference in a 272 and 276? duration is 228* vs 234*, and lift is .448" vs. .449"

I would say there probably wouldnt be a huge difference there anyway.


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## tdogg74 (Mar 1, 2002)

*272 camshaft measured @ .050"
Advertised Duration: 272*
Duration @ .050" 228.7*/228.7*
Valve Lift: .44835" / .44902"
Centerlines @ .050": 109.1* / 110.5*
Lobe Center: 109.8*
Valve Timing: 4.6/44.1 - 44.2/4.6
Valve Overlap: 9.1* @ .050"

*276 camshaft measured @ .050"
Advertised Duration: 276*
Duration @ .050" 234*/234*
Valve Lift: .449" / .449"
Centerlines: 110.1* / 109.9*
Lobe Center: 110*
Valve Timing: 6.9/47.1 - 46.9/7.1
Valve Overlap: 14*

The cams really are considerably different. Other than the lift, the 276* is a lot more aggressive...from timing to duration to centerlines. The mid range up to the top end is going to noticeably move more air.


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## unknowable (Apr 10, 2011)

tdogg74 said:


> *272 camshaft measured @ .050"
> Advertised Duration: 272*
> Duration @ .050" 228.7*/228.7*
> Valve Lift: .44835" / .44902"
> ...


Maybe I should upgrade here pretty soon. Already got the HD Valve Springs... 
I guess I just like to play it safe... I ride the highway a lot and dont want to blow her up.


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## tdogg74 (Mar 1, 2002)

You aren't going to blow anything up. 2.0's are pretty stout. Just stay on top of your timing belt's health.


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## unknowable (Apr 10, 2011)

tdogg74 said:


> You aren't going to blow anything up. 2.0's are pretty stout. Just stay on top of your timing belt's health.


So I want to upgrade my 272 to a 276. When i put in my 272 almost a year ago it was with a rebuilt head and I used a new set of head bolts. 

Question is, should my head bolts be safe with the 276, or should I consider getting some studs?


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## tdogg74 (Mar 1, 2002)

I'm not understanding what head bolts have to do with swapping cams? 

I only used OEM head bolts.


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## unknowable (Apr 10, 2011)

tdogg74 said:


> I'm not understanding what head bolts have to do with swapping cams?
> 
> I only used OEM head bolts.


ugh... well since a bigger cam would have a higher compression effect in the cylinder, I wanted to know if my OEM bolts would be okay. Thanks for your round-about answer.


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## mafiaman52991 (Jun 29, 2009)

you wont gain any compression by just changing the cam, if anything you would be losing dynamic compression, at lower rpms especially, becuase of the valve overlap with the 276° ,youd only gain compression by shaving the head, even then i believe that oem headbolts will be fine


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## tdogg74 (Mar 1, 2002)

unknowable said:


> ugh... well since a bigger cam would have a higher compression effect in the cylinder,


The cylinder charge boost/supercharging effect of scaveging with larger duration cams (valve overlap) doesn't necessitate you run ARP (or the like) stud bolts. OEM stretch bolts are just fine for your average bolt-on NA motor.

Unless you plan on removing your head numerous times, it's not worth the $100+ for the reusable bolts when stretch bolts cost $40 and work just as effectively.


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## unknowable (Apr 10, 2011)

tdogg74 said:


> The cylinder charge boost/supercharging effect of scaveging with larger duration cams (valve overlap) doesn't necessitate you run ARP (or the like) stud bolts. OEM stretch bolts are just fine for your average bolt-on NA motor.
> 
> Unless you plan on removing your head numerous times, it's not worth the $100+ for the reusable bolts when stretch bolts cost $40 and work just as effectively.


Thanks a lot. Thats exactly the answer I needed.


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## Glegor (Mar 31, 2008)

tdogg74 said:


> The cylinder charge boost/supercharging effect of scaveging with larger duration cams (valve overlap) doesn't necessitate you run ARP (or the like) stud bolts. OEM stretch bolts are just fine for your average bolt-on NA motor.
> 
> Unless you plan on removing your head numerous times, it's not worth the $100+ for the reusable bolts when *stretch bolts cost $40* and work just as effectively.


who are you getting them from? i pay $0.99/each bolt.. thats why i never went with head studs..

and usually, doesnt a bigger cam mean the engine has LESS compression? because the valves are open longer?


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## tdogg74 (Mar 1, 2002)

I always just picked up a set fro GAP when I needed them. Next day shipping.

And you are referring to dynamic compression.


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## unknowable (Apr 10, 2011)

I just got the Standard head bolts from TT back when i originally ordered my cam. $2.50 ea


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## Glegor (Mar 31, 2008)

tdogg74 said:


> I always just picked up a set fro GAP when I needed them. Next day shipping.
> 
> And you are referring to *dynamic compression*.


sorry, i was referring to static compression..


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## tdogg74 (Mar 1, 2002)

Cam duration does nothing to static compression; that is a product of bore/stroke/chamber volume.

Larger duration periods decrease dynamic compression.


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