VVT Cam profiles

plohl · Postby **plohl** » Thu Aug 24, 2017 2:57 pm

I'm like the opposite. Super massive appeal, skilled enough just financially challenged/can't justify spending thing money. Plus there's like no race class you could run it in - Prod sports and IPRA are both out, and even pushes you in to crazy classes for time attack.

If you're going to build up a BP4W, would it be worth going bigger cams? Or is the plan just some simple valve train work and stock bottom end?

StanTheMan · Postby **StanTheMan** » Thu Aug 24, 2017 3:08 pm

935c cams if BP blanks are available otherwise Regrinds of similar profile & lash adjustment
match ports & polish...the basic one
increase CR aggressive head shave
MS 2 pnp
valve springs
replace all the valveguide seals with OEM seals
Hope the valves & valve seats don't need any work....cause that then becomes exy. Not going to do it by hand again. I think it was a waste of time.
Probably replace the head bolts for good measure
Unsure if I need HLA or solids. Depends on the cam. 935C profile is for HLA's. I'm sure they can custom grind that for solids if required. But haven't asked.

essentially whats been done to Patchy on the 1.6 with extra experience this time around.

I currently have 66lbs valves fitted on Patchy which will get transferred across

I will also check protrusion of pistons & see if i can get a thinner head gasket. But will insure this time for minimum required clearance. will try to get the clearance down to 0.35mm....if i can

Cant afford to get a rotating assembly balance....although I'm soiling myself at the thought.

StanTheMan · Postby **StanTheMan** » Thu Aug 24, 2017 3:40 pm

probably will not see a huge amount of track time.....but the odd day here or there.

Alex 2550 · Postby **Alex 2550** » Thu Aug 24, 2017 4:57 pm

hey mate, in regards to shave for your records my BP4W head is done at 62thou so should see my cmpression go from NA8 9:1 to 10.5:1. i will decide after its on and running if i will up compression, regardless the bottom end will be rebuilt......at some stage. i want something between what i have now and my old 308kw atw FC and im hoping the upcoming setup gives me enough power to transform the car but not as much as the 7 or WRX.

StanTheMan · Postby **StanTheMan** » Thu Aug 24, 2017 5:30 pm

Just pulled the trigger on a 1.8 BW4...whatever it is

bigdog · Postby **bigdog** » Fri Aug 25, 2017 9:08 am

Borg Warner 4 speed auto gearbox? You've changed man...

StanTheMan · Postby **StanTheMan** » Fri Aug 25, 2017 10:22 am

StanTheMan · Postby **StanTheMan** » Sat Aug 26, 2017 12:26 pm

Alex 2550 wrote:hey mate, in regards to shave for your records my BP4W head is done at 62thou so should see my cmpression go from NA8 9:1 to 10.5:1. i will decide after its on and running if i will up compression, regardless the bottom end will be rebuilt......at some stage. i want something between what i have now and my old 308kw atw FC and im hoping the upcoming setup gives me enough power to transform the car but not as much as the 7 or WRX.

OK so if the compression starts at 10:1 on the NB8A it should take it to 11.5?

rascal · Postby **rascal** » Sat Aug 26, 2017 2:33 pm

NB8A's are 9.5:1 from factory...

StanTheMan · Postby **StanTheMan** » Sat Aug 26, 2017 3:29 pm

rascal wrote:NB8A's are 9.5:1 from factory...

ok so its more like 10.5 to 11:1

StanTheMan · Postby **StanTheMan** » Thu Aug 31, 2017 1:07 pm

Recoieved some cams

very excited. These are a little more.....errr....agro perhaps

Lobe @ 108
Duration at 0.05" is 238
Duration at 0.02" is 260 deg and hats the advertised duration. But I understand 0.03" is the usual place where advertised duration is measured?
lift .....is massive

so I guess it varies from cam to cam on how quickly it ramps up & were they measure duration but if you take that as normal advertised duration it must be closer to 290-300 ? :shock:

It will be a while before I can give a verdict on these as i'm now contemplating on how much I can take off the head