Jump to content
The mkiv Supra Owners Club

Benefits of higher lift cams?


JackyBoi

Recommended Posts

I'm looking into buying some 264 camshafts for my VVTi Supra but am curious into what the actual benefits are, and as I'm no mechanic I thought why not ask you guys:

 

Does having higher lift cams installed increase horsepower/torque, and if so how much?

 

Can they be detrimental to any engine/turbo components?

 

Anything else worth upgrading when fitting higher lift cams?

 

Thanks guys :thumbs:

Link to comment
Share on other sites

In laymens terms they basically hold the valves open for longer. This means that more air can get into the chamber during a stroke and more gas can get out of the chamber during a stroke. Various combinations are used for various applications. If you check your dyno graph and notice a drop off in power then this would suggest that either your turbo is gassed or you could do with cams.

 

There are pro's and cons. Adding longer duration cams will shift the power up the rev range a little. It allows for more power, but at a slight cost of low end power/spool. Fancy mapping can help iron this out though.

 

If you are using stock cams, I would expect that at least 256 cams would make a difference. Being VVTi I'm not sure how just changing the exhaust cam works out.

Link to comment
Share on other sites

In laymens terms they basically hold the valves open for longer. This means that more air can get into the chamber during a stroke and more gas can get out of the chamber during a stroke. Various combinations are used for various applications. If you check your dyno graph and notice a drop off in power then this would suggest that either your turbo is gassed or you could do with cams.

 

There are pro's and cons. Adding longer duration cams will shift the power up the rev range a little. It allows for more power, but at a slight cost of low end power/spool. Fancy mapping can help iron this out though.

 

If you are using stock cams, I would expect that at least 256 cams would make a difference. Being VVTi I'm not sure how just changing the exhaust cam works out.

 

That sounds about right. On 1.7 bar my car surges which I've heard could be solved with higher lift cams.

 

Im getting Srd stage one 264 as my stock cams are at there limit ....http://www.mkivsupra.net/vbb/showthread.php?229575-SRD-Stage-1-2-and-3-Camshafts

 

Mine is pre vvti but I'm sure it's beneficial to have cams mate

 

Guessing those aren't priced for VVTi then. I was quoted over £1k for VVTi 264 cams, brand new.

Link to comment
Share on other sites

I would recommend the HKS 264 cams for a VVTI

 

As Jamie said they don't cause any noise and the gains are very good

 

I can supply them if needed, just drop me a PM

That was the one thing that let my car down.

 

Go HKS, mate. Any other make and it sounds like a diesel from the 80's on idle.

Link to comment
Share on other sites

Some profiles cause the VVTi actuator to rattle. The cams themselves are not the source of the noise. A high lift cam opens the valves wider, they do not *NECESSARILY* hold them open longer.

 

Valve spring stress, retainer stress and cam lobe pressures increase. If they are pretty wild the lobes may catch on the bucket bores, or try and flick the shim biscuits out. Really wild ones will need under bucket shims, and custom cams may need larger diameter buckets and a lot of trick machining.

 

Cheap cams are ground on stock blanks, and the extra lift produced by reducing the base circle diameter. You then find you need very thick shims. Quality ones are done on custom blanks or from billet. They should use stock range shims

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.