21 Turbo 21t cams

[Haz]

I'm debating a cam again. I can't seem to find any old threads so starting a new one. Although Catcams have some nice ideal specs they are not an option atm.
The Europacup had good lift but had too much overlap for big boost. Re grinds of the std is obviously an improvement but I don't think offer enough lift.
What's out there?

 

[DaveL485]

Just mulling your cam over again, I know I need a life!

Yes you do

I'm not giving all my secrets away anyway lol

 

[Haz]

Yes you do

I'm not giving all my secrets away anyway lol

Oh like that is it lol, only trying to help. Guess we'll just have to see if it works first
Im sure the 12v will require an odd spec but the principals will be the same.

 

[DaveL485]

Oh like that is it lol, only trying to help. Guess we'll just have to see if it works first
Im sure the 12v will require an odd spec but the principals will be the same.

Yep, it's all a bit suck-it-and-see, same with compression, throttle bodies, combustion chambers, spark plugs, exhaust manifold....

 

[ratmangta]

Try these guys Haz .They do all the custom work for MartinF on our v6 lumps + all his Fiat stuff ..

http://www.newman-cams.com/index.html

 

[Andyquadra]

Try these guys Haz .They do all the custom work for MartinF on our v6 lumps + all his Fiat stuff ..

http://www.newman-cams.com/index.html

We've looked at them before with Dave's 12V and they weren't much cheaper on a regrind than catcams on a billet cam

 

[Haz]

@Andyquadra and @la21t, did you both set your cams up the same via the sheet, apart from retarding with the vernier? Have you experimented with adjusting valve clearances to alter duration and overlap?

 

[Andyquadra]

@Andyquadra and @la21t, did you both set your cams up the same via the sheet, apart from retarding with the vernier? Have you experimented with adjusting valve clearances to alter duration and overlap?

My vernier is still in the box LOL never heard of adjusting the valve clearances to alter duration and overlap. Too tight and it'll hold the valve open and too loose and it'll rattle it's tits off?

 

[ratmangta]

Was on about for advice/tech help getting what you want.They are pretty helpful guys .Cheapness is a bad way to buy these things anyway ........but you say they were cheaper anyway so the point is mute ....winky smiley etc

 

[Red21]

Can I put my two pence worth regarding adjustable cam pulleys especially on Ph1 distributor engines, unless you can adjust the distributor to compensate for any adjustment to cam timing the position of the rota arm in relation to the cap HT points for a given ignition firing point i.e. #1 cylinder will be to advanced /retarded which may cause the HT voltage to miss jump and track to earth and create running problems.
True??

 

[Andyquadra]

Was on about for advice/tech help getting what you want.They are pretty helpful guys .Cheapness is a bad way to buy these things anyway ........but you say they were cheaper anyway so the point is mute ....winky smiley etc

All I remember was that regrinding a 12V N/A cam was never going to get what we wanted and was only marginally cheaper than a catcams billet job designed to turbo applications

 

[Andyquadra]

Can I put my two pence worth regarding adjustable cam pulleys especially on Ph1 distributor engines, unless you can adjust the distributor to compensate for any adjustment to cam timing the position of the rota arm in relation to the cap HT points for a given ignition firing point i.e. #1 cylinder will be to advanced /retarded which may cause the HT voltage to miss jump and track to earth and create running problems.
True??

I have to agree which is why my engine is going to be converted to wasted spark when its mapped

 

[Red21]

I have to agree which is why my engine is going to be converted to wasted spark when its mapped

Another possible option is to use a distributor from a old Master van or Espace with the short dizzy cap as this is driven from the oil pump shaft. The only problem with this is finding a distributor that has not been damaged.

 

[Haz]

My vernier is still in the box LOL never heard of adjusting the valve clearances to alter duration and overlap. Too tight and it'll hold the valve open and too loose and it'll rattle it's tits off?

Is that for sale as I'm ordering one next week? Not really, if it has a clearance then it's slack whether it be .1mm or 1mm, and rattle would just be the slack taking up in the valve train so clearance can be bigger shortening the duration and more importantly reducing overlap.
Reducing clearance depends on how much run out the cam has so each lobe would have to be checked. Ok, there's not lots of gains but you can advance the inlet with tighter gaps and retard exhaust with slacker. Increase lsa and reduces overlap, not much but it all helps. From .3 to .1 can see as much as 30* more duration, or in the case of the piper 276 the duration could be reduced to 270, 6* less overlap at tdc.

 

[Haz]

Yes, limitations but the vernier is to to correct peak angle as it may not be possible from a regrinds, besides, most are going standalone for the ease of altering parts and quick re maps.
I also came across your cam details on a build thread of yours.
Kent f528- clearance .25mm, inlet lift 5.69mm, exhaust lift 5.69mm, [email protected] clearance 278*, duration@1mm lift 219*, full lift@110atdc.
Results peak torque of 290lbft at 4392rpm and 264hp, wheel power.

Edit: @Andyquadra see the clearance/duration figures

 

[Andyquadra]

Is that for sale as I'm ordering one next week?

Yes brand new in the box catcams, I'll take a photo tomorrow. only selling it as the catcams cam I have has one on it already

 

[Haz]

But if you take a photo it won't be in the box or new . Tbh I'm not bothered what brand atm. I think I'll ideally need 10* retard, one tooth is 8.5 but would nice to get it spot on

 

[Haz]

A little info to add, I've measured up the std cam and compared them to the others mentioned so far, the piper 276, catcams 268 and Kent 278. They are all basically the same, which they should be if reprofiled as there's not a lot to play with (although I think 10.75mm lift can be achieved, lobe design would make it 310* duration) . The difference is the lobe design. The catcams has steeper ramps allowing an extra lift and in the middle for overlap at 1mm, but due to steep ramps may have the most lift here. Lift at tdc is a little more than ideal. Piper has slightly longer duration, less valve lift and more overlap. Kent has the longest duration, the least valve lift and overlap.
I only know the lift at tdc for catcams, so I would assume Kent is more suitable.
I'm still waiting on piper to see how close they can get to my desired specs

 

[la21t]

Let me know....I've a spare one here I might send off

 

[Haz]

Seems to be a pita tbh. After several phone calls discussing what I'm wanting/trying to achieve and what they think they can do, they are wary to do much mainly due to lobe design and rocker contact and don't want to give much away as to why I can't do what I want. Or they can't be bothered for the cost of a reprofile. They've offered 3, 276 has the least lift and over 2mm lift at tdc, a 274 with a little more lift, not much less lift at tdc and a 258 with the most lift which is what I've gone with, but altering it differently than they normally do but how much they can't predict. Doubt they'll give me the finished specs and I don't have time to measure as just getting thrown in when it arrives. Guess we'll see how the dyno curves compare, in theory it should be more gradual but peak higher.
I've one more cam to measure here when I get time too.
I'll get back in touch with them once I know all that to see if they can improve it if it's going in the right direction

 

[DaveL485]

I'm surprised you went with a 258, isn't the OE cam a 255? Yes better lift but I have always preferred longer opening than higher lift, within reason. Each to their own eh