Which Cam?

[mattcogg]

Hi
I've been wanting to get a cam for ages but I am really unsure about what make and model to get. I want one that is still predominately for road use but maybe kicks in about 3 - 3500 revs. Are there any side effects to having a cam and what about if you have 40s as well. If anybody could help please let me know some product codes or helpful websites or just some advice.

[mikeoxford]

kent ast 2

kicks in at around then and goes waaaaaaayyyy up the power band

its quite a lumpy cam.

go in the 1.4 8v tuning sticky thread at the top of this forum, everything your asking is in there.

twin40s LOVE lumpy cams

people say dont go too lumpy (wild) cams if its JUST round the town driving as you will soon get pissed with it

but id say go as lumpy as you can get away with!

a few people say for little or no extra money, lumpier cams are better.


the ONLY down side i know to a cam is:

depending on how lumpy it is and because of the rev ranges and changes in engine bands etc

to do 30 - 35 constant you may have to have it in 4th or even 3rd depending how lumpy it is - not 5th - itll struggle too much. thats a bit of an exageration i think but u get the point

[Dan]

So you want an engine for all top end power and sacrafice all that low down torque, You might find that if a mate went for a low/mid range cam with a bit more top end on same spec engine as yours he would run rings around you unless u got to a track day or summin where it would be all high revs and keeping power within that band of power. Its ok to have a big bhp figure from some mods and a large cam, but you shouldnt forget about torque as thats what gets the engine going in the first place.
A kent nvo 62 cam has a power band of 1500-6000, so this cam would be spinning nicely towards a gear change by the time the cam u say about would be just getting going.

[locky]

I think there should be a sticky on camshafts!
Theres quite a few questions bout them,
and it'll help people decide on which camshaft suits their engine!
If ne admin/moderators have some spare time of coarse!
If not then not to worry!

[cornish]

Quite interested in this one too, i've got a Courtenay High Torque cam along with 40's, it ain't really lumpy at all and will rev well up to about 6500rpm (as indicated on rev counter).

I fancy getting something a bit wilder though :D

[mikeoxford]

cornish mate what duration / specs etc is the cam youre running now?

dan has got me scared!

lol

i bought an engine with kent ast2 and other work t40s etc done a while back, thats why i planned to use it.

if it is to leery i may have to find an alternative!

but if your saying you want to go lumpier - i may be all right!

[Dan]

I think (from past chats to mc) that the courteney high torque cam is similar to the said kent cam i posted about above. I did run this but with all the mods i had done found it had a tad to much low down and wheelspin was a pain in the arse. (car did rev to 7150 before power drop off tho lol). At the moment i have moved onto the piper 285 degree cam in the hope that shifting the power up a touch i can eliminate some wheelspin and turn it into productive power. This cam has been designed (according to piper) for use with twin 40's, the next attempt will be a 300 degree cam if i have no joy but dont really wanna go that high as mot emmissions will be a joke, they are already but managable :wink: .

1650 Rebore/hone block, Pistons, Ground crank, Main bearings, Big-end bearings,Full dynamic engine balance, Lightened flywheel, Faced flywheel, Skimmed block face, Oil pump, Water pump, All gaskets. Blydenstien b+ head, Piper 285 cam springs tappets etc etc, twin forties, piper exhaust system, plugs, leads blah blah blah

Thats what i run at the moment and engine is only in state of half tuned but this cam appears to be just right for me. When tuned it will give 150+ bhp with a good dose of torque to boot, so good all round power not just one end or the other

[Chris_W]

Specs for NVO62 and AST2:

Make Model Part Number Application Power Band Cam Lift Valve Lift Duration Timing Figures Valve Timing Valve Clearance

Vauxhall Cavalier, Vectra, Astra, Nova, Corsa 1.4/1.6 P NVO62 Sports Injection 1500-6000 6.90mm 11.67mm 270 Degrees 21/69 69/21 114 Degrees 0.00mm

Vauxhall Astra, Kadett, Nova, Corsa 1.3 AST2 Sports 'R' 3000 - 7000 6.09mm 10.30mm 290 Degrees 36/74 74/36 109 Degrees 0.00mm

I'd say that the AST2 is probably a bit wild for road use, but hey, it might work. I'd prefer something that works low down, otherwise how else you gonna win the traffic light Grand Prix ;)

Chris

[Chris_W]

Just found this:

Vauxhall Astra, Kadett, Nova, Corsa 1.3 AST3 Supersports 2500 - 7000 7.49mm 12.66mm 280 Degrees 34/66 66/34 106 Degrees 0.00mm

Probably a compromise between a really wild cam and keeping it driveable.

Chris

[mikeoxford]

well for what i paid for the whole caboodle, i could consider it that the rest of the engine came as a freebie.

the engine has only done 4.5k since rebuild - so basically its all new parts for nothing.

ill try the ast2 cam and if it is a bit lumpy ill just have to go and sort meself out with sommat else! all i wanted really was the 40s - was going to get a cam after

understand what you mean about torque etc etc.

so if worse comes to worse ill sell what every i dont need and by one of the better cams mentioned - im not going to put me cam down one way or another as it ent even in my bloody engine yet!!!!!

[locky]

Chris wot cam have u got? im keeping the injection system on the car, just wondering wot cams people have got with the gte/gsi engines!

[CP]

I tried a Piper 275 ( fast road) but changed to a Piper 285 which is specifically designed for twin 40's. I preferred the 285. TBH there is only a very small difference at low down which can be got round by changing down a little earlier. I'm running a really peaky set up in my 16v at the mo. and i now realise what its like to have no low down grunt. I would have no hestitation in going for at least a 285 if I had twin 40's on. BUT i would get a B++ head done sharpish cos without it the other mods are expensive and relatively ineffective

[locky]

CP, have u got any more info on the b++ heads, wot does he do to the heads, or does he give u a new head which is ported or whatever!
Wots the price on the heads aswell?
Cheers,

[mikeoxford]

well the regular kent ast 1 is 270 degree lift and ast 2 290 degrees

if you would go for 285 and assmuing im rattling off the correct numbers, id guess that the ast 2 may be alrite after all?

as i said though my engine is being done in january sometime, so ill post comments then! until then ill guess ill hav 2 wait and see!

[mikeoxford]

heres the specs of them if anyone interested

Kent AST 1

Make Model Part Number Application Power Band Cam Lift Valve Lift Duration Timing Figures Valve Timing Valve Clearance
Vauxhall Astra, Kadett, Nova, Corsa 1.3 AST1 Sports 2000 - 6000 6.24mm 10.55mm 270 Degress 29/61 61/29 106 Degrees 0.00mm

Make Model Part Number Application Power Gain Extra Machining Required?
Vauxhall Astra/Nova 1.2 1.3 OHC AST11K Sports Camshaft 8 Bhp No

Kent AST 2

Make Model Part Number Application Power Band Cam Lift Valve Lift Duration Timing Figures Valve Timing Valve Clearance
Vauxhall Astra, Kadett, Nova, Corsa 1.3 AST2 Sports 'R' 3000 - 7000 6.09mm 10.30mm 290 Degrees 36/74 74/36 109 Degrees 0.00mm

Make Model Part Number Application Power Gain Extra Machining Required?
Vauxhall Astra/Nova 1.2 1.3 OHC AST2K Sports 'R' Camshaft 12 Bhp No

[mikeoxford]

another thing ill say qwikly is have a luk in the 1.4 8v tuning sticky thread

i think aragorn posted, and said basically that as standard the 1.4 cam IS BETTER than the 1.4 as it has morelift or one of the figures was better.

w8 there ill cut n paste



i noticed summat interesting: you say above to use the 1.6 cam, but the 14nv cam actually provides more lift: 14nv, 6.12mm inlet and exhaust; 16se 5.6mm inlet 6.12mm exhaust now i realise its small but the 1.4 cams will be easier to find in the long run than the 1.6 cams and as far as those numbers go teh are better




Well spotted. What was the difference in duration?

When you buy an aftermarket camshaft, most manufacturers actually quote the same part number for both engines. Shows there is little difference, and both are interchangeable


found that interseting

[spanishfly]

i just finished puttin my lump together:)
tis a 1.4 sr with twin 40's, i have gone for the piper 285 cam!!
just went for a little L plate drive and although (due to running in) i am only taking it to 3000 rpm now it feels quicker than my sr running the 32/34:) oh yes and u can feel the cam comming in nicely!:)
i have the 1.3 head:) which i've ported and polished the head my self.....for now:)
when i get the ?650 together i'll own a b++:)

[Slatter]

Well ive had my 40's on the standard engine for about 5k's now.

And the headgasket has just gone. Im surprised it didnt go sooner as i rev it past 7000rpm :)

Good excuse to put my PMC 285 cam in and vernieer pully on.

And have my head sorted !!!!!!!!!!!!

[mikeoxford]

:oops: JEALOUS

lol

gotta get my engine work finnished finally!!!

got me mechanic sussed for this month :P

[Shorty]

so can u put a 1.4sr/sri cam straight into a 1.2spi?

[mikeoxford]

so can u put a 1.4sr/sri cam straight into a 1.2spi?
oh yes