Cam timing

[Adams_16v]

When i had cams and verniers fitted they were setup to Kent manufactured recommendaion.

Is it worth getting them timed as best they can be? and would i need to take itto the RR?

I rang a guy before I had the work done, and he said he could set the car up for me once the engine was built! im gonna ring him again as hes only local, but wanted to know for myself b4 i spoke to him!

Cheers

 

[JAY172]

you time up the cams using a angle chart on the crank and a vernier gauge on the tappet/bucket.when i did my mates it seemed a bit of a pain in the arse but worth doing as both cams were quite a way out(used the pulley marks to fit them and rebuild the engine.then checked cam timing as per above/kent instructions)

 

[Adams_16v]

yeah they are set to kent instructions, and it runs spot on. Just wondered if there may be a few horsies hiding in there than could be released!

What would the guy do on the RR to set it up then? bearing in mind he wont be touching the ECU. Just adjust fuelling using the PBV?

Cheers

 

[JAY172]

the rolling road/set up could highlight ingnition problems etc (eg,weak spark plug or coil) and allow the pbv to be set up correctly.they wont touch the cam timing on a rr as this was done when the engine was rebuilt but i suppose it could show if there setup correctly or not by comparing the exspected bhp and the actual bhp(see if there is a large difference/engine unusually underpowered compared to the mods that have been done)

 

[BenR]

if the engine is in the car then using the crank angle gauge means box and clutch off......

Using the lift at TDC method is FAR easier and more accurate.

 

[JAY172]

i used the angle chart on the crank pulley side.

 

[BenR]

with it in the car!?

 

[JAY172]

i did it out of the car but i think i could have done it with the engine in as the angle chart was only about the size of a cd and i put it in place of the bottem pulley with the help of some washers to pack the bolt out.

 

[BenR]

exactly why he lift on overlap at TDC is so easy!

 

[BenR]

engine to TDC, dail gauge on inlet valve tappet, turn anti clock and youll have the lift figure for the inlet cam at TDC. If its off, adj the cam clockwise for more lift, anti for less..........this way you dont need ot read degrees of crank rotation and fiddle about.

Same for exhaust but turn clockwise to measure lift and anti clock on the cam for more lift at TDC.

Much easier on an 8v as itll have 1 camshaft and the LCA will help you figure out lift on overlap as itll be the same amout for inlet and exhaust.

You can fiddle about with timing after you get the base setup that way.

 

[JAY172]

so you mean rotate it so it opens and closes the valve once so you could meassure max lift and then set the engine to tdc to see if max lift is obtained and adjust if reqd.so you adjust it by meassuring cylinders 2 or 3?

 

[BenR]

no, max lift isnt brought into it.

You set the engine to TDC on the non firering stroke.

And If the cam company doesnt tell you the lift at TDC then you can calculate it from the LCA. On overlap the values should be the same unless specified.

So you just rock the engine back and forth measuring lift TDC for inlet and exhaust.

This is all on cylinder #1.......pully side as some people put #1 as flywheel side.

 

[JAY172]

so if the cam company gives you the lift at tdc you can just lock the engine at tdc and meassure the lift on the cylinder specified by the cam company and adjust as needed.i think the cams i fitted used the angle chart to find tdc centre and the dial gauge to find the centre of max lift on the cylinder they specified.my mate had fitted the cams and not checked the timing so when his headgasket and clutch went i pulled out the engine and timed up the cams when i rebuilt.it was a completly different car after that it went loads better.one of the cams was i think 10degrees out so it shows that buying vernier pulleys is really essential to get the most out of the cams.only ever fitted about 5 sets of performance cams so ive always followed the instructions that they come with.not meaning to sound thick but whats LCA stand for?

 

[BenR]

Lobe Centre Angle

The amount in deg between max lift on inlet and exhaust.....dictates overlap.

 

[andy-reid]

Re: Archived Post from old forum

i did it out of the car but i think i could have done it with the engine in as the angle chart was only about the size of a cd and i put it in place of the bottem pulley with the help of some washers to pack the bolt out.

i use magnets to stick the timming disc on to crank pully(magnets from inside computer hard drives megga strong)

 

[Dan@SJM]

Holy thread revival batman!

 

[andy-reid]

Re: Archived Post from old forum

engine to TDC, dail gauge on inlet valve tappet, turn anti clock and youll have the lift figure for the inlet cam at TDC. If its off, adj the cam clockwise for more lift, anti for less..........this way you dont need ot read degrees of crank rotation and fiddle about.

Same for exhaust but turn clockwise to measure lift and anti clock on the cam for more lift at TDC.

Much easier on an 8v as itll have 1 camshaft and the LCA will help you figure out lift on overlap as itll be the same amout for inlet and exhaust.

You can fiddle about with timing after you get the base setup that way.

how did you get to the valve to check with the top on?? as this holds cams down and pullys need removing to get top on&off???

 

[Dan@SJM]

He's talking about the f7 series.

 

[Gray]

Re: Archived Post from old forum

10yr old thread revival, wowzers!

The people you are quoting no longer frequent the forum.