Go Faster Camshaft

Any opinions on this one?

http://www.ebay.co.uk/itm/281241679766?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

I thought the c&b cams always had thinner lobes width wise on there sohc's.
And not that I can tell from the pic very well but that looks the same finish between the lobes as my kent cam which is chilled cast billet and not steel billet which I think would appear smoother?

Cheers Rich, I wasn't sure about it so don't think I'll bother

Maybe drop unograle a pm as I think he has/had one,pretty sure there billet steel with thinner lobes.

Think this could possibly be a pic of one although not 100% sure...

I'm sure Paul will share any info on this one

Yes yes, it was a real C&B steel billet, i was going to buy it and add it to my collection   

The give away was the curve up to the lobe where it is machined that way.

My lady friend could have picked it up for me in her neck of the woods, missed out, someone bought it outta auction, but who......?   

Debatable how much gain you would get out of it and its characteristic but, all dependant on the mods around it, perfect for road as it says and a fine bit of metal nonetheless...


Trust Rich to find a pic    nice one mate, that's bang on !!

Haha thought you might have been watching it,i am still not convinced though,that ebay one the lobes seem to wide and the space between the lobes to little?
It just looks like a regular chilled cast cam the same as the kent/piper jobbies,to be fair the pic is shite though   

I bought this and cheap too. It seems good but haven't had a chance to have a good look at it yet.

Anyone have any idea if I will gain much with standard management?

Liam

standard ecu will just run lean top end, fitting the cam will just make it run leaner

Okey, its definitely cast and not ground from a billet. It has CB170T stamped on the end but that could have been done by anyone with a set of letter punches. I will clean it up and see if I can find out where its from.

Liam

Sorry, I meant CB270T not CB170T.

Liam

So, I've cleaned up and had a good look over this cam. It is a fiat cam from what I can see. The marking that gives this away is the pyramid of four lines that you see cast into most Fiat/Lancia parts. So, if it is Fiat and the number CB270T stamped is real then it must be a re-grinding by Colombo & Bariani.

Liam

Yeah sounds like it could have been reground to c&b specs, but I would measure the cam lift to be certain its not just a stamped up stock one.
I have heared more than a few rumours about advanti so its best to check it...

http://www.lunatipower.com/Tech/Cams/CamSpecTerms.aspx

http://www.puntosports.co.uk/forums/showthread.php?19672-Avanti-in-court&highlight=gt3+camshaft


Also as its a regrind when you come to fit it you may find it will need extra thick shims or in some cases top hat shims due to the smaller base circle where it has been reground.

Also as st1 pointed out you may find it will run dangerously lean at the top end with the cam fitted which can be tricky to over come with the stock management, especially if the boost has been raised aswell.

I will do that, thanks for the heads up and links. Its a bit out of order if Avanti are doing that sort of thing! Why cant people make a honest living?!

Yes, I have been on C&B website reading about fitting a re-ground cam and I wont be fitting it until I can increase fuel.

Liam

I have some photos and lift measurements.

Here are the numbers: In = 10.3 Out = 8.9

These numbers match C&B's 270 cam for the Uno.

Here are the photos I have taken.

Inlet lobes for no. 4 piston






You can see here that the CB270T has higher lift than the standard 1301T cam.


And here: Inlet no. 1 cylinder.


If anyone has any thoughts on this please let me know.

Cheers

Liam

Seeing clear pics now at least shows this is not a billet as i first thought....

The old pics showed that it has the same curve up to the lobe on the shaft, but as Rich pointed out too, i have since had a quick butchers at mine and yes, the lobes are narrower too !

Looks in good shape,could of possibly be reground on a different core other than the 8mm lift mk1 cam, not that it matters as it proberly helps.

I say that as it has the little circled C in your 2nd to last pic,my last cam had the same and it was around 9mm lift and all the other mk1 cams I have seen have always been 8mm lift without the C.

I tried to find out about this but came to the conclution it was proberly out of a tipo/uno 1.4na due to the lift,another cam that has the circled C is the x1/9 cam and that has even higher lift.
Not sure about the mk2 or punto but think the circled C thing was a thing on more of the fiat earlier cams.

Also not sure if its even possible to get than sort of lift from a stock mk1 regrind without adding material to the lobe which definataly dont look to be the case.

Not that it will tell much but what are the base circle sizes of them 2 cams?

I agree, it looks like its done very little work.

Base circles are approx as I used a non digital Vernier Caliper (but good ones)

1301: In 28.0mm Out 28.0mm

Ebay Cam: In 25.0mm Out 27.5mm

Liam

Not 100% sure but I think the base circle should roughly relate to the valve clearance and if that's the case you should get away with it on the exhaust side but will most proberly need top hat shims on the inlet?

Also seeing your project thread I see you are running a mk2 engine/management,they run slightly larger injectors and I think fuel different/possibly better than the mk1s.
You may possibly get away with fitting the cam with the likes of an adjustable fpr and pressure increase.
I am not familiar with the mk2 fuelling so can not comment but I suspect you will have better chances of getting it to run right on a mk2 setup.

So, at what point do you need a top hat? When shimmed I should make adjustment according to factory spec? Yes I'm going to get a fpr and try raising it between 3 and 5psi (advised by Guy Croft). I also have have air/fuel meter fitted.
Its not one of my priorities at the moment as I'm working on my gearbox.

Thanks for the help.

Liam

I cant remember what fiat shim sizes go up to tbh,and this is going on the assumption that the 3mm smaller base circle will create 3mm extra clearance which I am still not sure is correct but in theory it should ? lol
Maybe give the likes of piper or kent a call and see what they say?

The options I can think off are oversize shims,top hat shims,cam box skim and/or possibly machining the top of the actual valve.

I think fiat shims may possibly come in sizes from something like 3-5mm so once again assuming that you will need around 3mm larger shims it will proberly put it out of this range.
Larger shims may well be possible to get but people argue that with to larger shims you are more likely to flick one off and they also complain that its not worth adding the extra weight to the valve train.
If the above are valid points I do not know.

Top hat shims sit on top of the valve and under the bucket and I think are quite commonly used with some piper cams,most likely with there regrinds.

A Cam box skim can be done to close the clearences but this will also effect the exhaust side and as the exhaust don't look like it will be quite as far out at only .5mm I don't think this is the way to go.

If you take to much off the cam box for the inlet to come back into spec you will possibly end up having to machine the valve tops of the exhaust to make the clearance larger for them other wise they will be to tight
Also worth noting that skimming the cam box will effect you cam timing slightly,possibly advancing it I am not sure?

As above though this all depends if the smaller base circle will effect the valve clearences as much as I think they will.

As for shimming 9 time out of 10 you will get away with standard fiat spec as the after market manufacturers don't seem to often deviate to far from it.
Idealy though and if you know the full specs of the cam it should be shimmed to the manufacturers clearences,the cams are designed with there own opening and closing ramps specific to that cam profile and there clearences should work best with it.

When fitting always use new shims or at the very least flip the old shims if they still have a good side,never use old shims on a new/different cam, as you may get unlucky as I found out  on my tipo cam as it must of picked up and started eating away at the lobes lol

Also lots of cam lube and prime the oil pump if possible and follow the 3k for 20mins from the off bed in procedure,worth looking into this as there are various ways.

Also maybe consider an extra zddp additive in the oil if you are paranoid like I am lol especially maybe why you bed it in.

To time your cam with a adjustable pulley if that's what your going to do you will need to know the cams intake lobe centreline angle.
There are other ways like the lift at tdc method but i think the lca way is more commonly used.

I am still not totally sure about this but i started a thread on puntosports a while back,my line of thought was that if the stock cam lobe centreline was different to the aftermarket one you are fitting is that if using the stock pulley on the aftermarket cam it would automaticly either be timed in advanced or retard using a stock pulley as the lca's are different.

This was the case with my kent cam which had a 105lca instead i think what was 112lca as stock,i ended up having to get a new pulley.
This also can all be affected by how much the block/head is skimmed and gasket thickness etc to what you cam timings doing.

http://www.puntosports.co.uk/forums/showthread.php?129589-Fast-road-cams-timing-and-vernier-pulleys-technical&highlight=

Fuel pressure well i am not going to argue with crofty but imo I would not raise it much higher than 15psi(4bar base),3-5psi is very conservative imo.

I know what he is proberly getting at with spray pattern etc and in extreme cases the injector wont fully open correctly with to much pressure behind it but i have never really heared of it unless running silly high pressure.

This is obviously also boost dependant as on a stock fpr it will raise 1 to 1 (1.7fuel-1boost if using an fse fpr) with the boost pressure so if running extreme boost you might want to think about it.
You would also need a good pump to be able to supply these sort of pressures.

All fuel pressure adjustments should be made at idle with vacuum disconnected,base pressure.

I use to run 4bar base over the stock 3bar with an fse 1.7-1 fpr,uprated pump and 18psi odd and had no issues other than it still was not enough and would still run lean.
I also unknowingly used to run 6bar base on the same setup years back and never had any problems although the pump was proberly maxed out so wernt making much more pressure on boost i would not of thought.

Anyhow that's just my opinion 4bar base would be my limit especially if using an fse 1.7 fpr and also have a good fuel pump to back it up.
As i mentioned though i have no experience of the mk2's so i could be wrong so always double check,but even on other types of car 4bar seems a reasonable limit.

As for tuning it if its anything like a mk1 you will need to try and find a happy balance by adjusting the afm bypass screw to reduce the fuelling at low revs cruising.
The afm on the mk1 only controls the fuel at idle/cruising,once on boost the afm will be at max open and the fuelling is then dictated by the ecu,fuel pressure and coolent temp and air inlet temp sensor in the afm.
You may find to get it to fuel correctly on boost by raising the fuel pressure you may run out of adjustment on the afm screw to lean it in the low revs.
This is when it gets tricky and you will need to adjust the spring tension in the afm and can bring a whole host of more troubles.

You may find a happy balance you may not,its all trial and error and if you make a big error you can stuff you engine,its all a juggling act between boost,fuel pressure and afm tweaks.

Tbh all the above is abit of a bodge but it seems its the only way to tweak the stock management,on the mk1 that is anyway.


Also to be noted is all the above is just my opinion,i am not a mechanic just an enthusiast so anything i post should not be taken as correct,it just how i think/hope it works lol.

Also what is you air fuel ratio atm on flat out on boost at wot

Just dug this up with the top hat shims...

http://www.puntosports.co.uk/forums/showthread.php?70433-Piper-cams/page4&highlight=piper

Also another tip while I remember is to always shim it up with the cam box gasket fitted,idone it once on the bench without and had to do it again lol.

I also remembered this thread but the piccys don't seem to work anymore,looks like he was running to rich in the low revs.

http://www.guy-croft.com/viewtopic.php?t=239

Tbh if you want it perfectly right you will proberly need to fit different engine management lol

Cheers for the effort!
So, my AFR at full throttle is 12.1 with 1bar boost, It runs very well. I do use millers fuel additive on top of Tesco 99RON effectively giving me 101RON

Liam

12.1 is about spot on,does it hold this flat through out the rev range or start to lean out up in the high revs?