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How much duration and lift can you get before you have to change to solid lifters in a B6 engine?

was looking at 264 9.5mm intake and 264 9.3mm exhaust. can anyone confirm if that will be okay?

Also Im after heavy duty valve springs, again without the need to go solid lifters? Basicly due to the $ factor and time.


Anyhelp? sheck i know you got hks ones 256? or 264?

My cams didnt require any valvetrain upgrades, they are the HKS ones at 264 deg and 9.something lift.
I'm pretty sure that my valve stem seals are going a little cause i get a bit of smoke on startup and when it was on the dyno it got a little when in high rpm and backing off, otherwise its sweet. Not sure if this is due to old age or from the cams. Doubt it was the cams though.

Dave

PS i've heard of ppl using GTR valve springs as an upgrade, so if you can find a set then that could be a good option.

I have a rebuilt/worked B6T with aftermarket cam profiles.

My engine has an exhaust cam with 254 degrees duration and lift of .401\" (10.2mm). The inlet cam I'm running has 245 degrees duration with a lift of 0.3556\" (9.017mm). My engine builder said to me that I was only a few thou under the limit of the valve springs and would also have to seriously consider solid lifters instead of the HLA's if I went any bigger.

The particular profiles I've used are a proven combo on the street as well as on simulation software so I was quiet happy to stick with them and use the standard springs and HLA's.

rjr666 wrote:How much duration and lift can you get before you have to change to solid lifters in a B6 engine?

was looking at 264 9.5mm intake and 264 9.3mm exhaust. can anyone confirm if that will be okay?

Also Im after heavy duty valve springs, again without the need to go solid lifters? Basicly due to the $ factor and time.


Anyhelp? sheck i know you got hks ones 256? or 264?

Manley (not sure of spelling) make a set of spring fr the mx5 that will work with stock HLAs, as do Competition springs in QLD.