C Series Cams

[Os8472]

Been doing some more research on N/A engine tuning to get ready to build the engine for my brothers car and the 1 thing that keeps coming up on any serious N/A build is cams but I can find bugger all in the way of cams for an N/A C1J :(

Was playing about with the cam wizard on here and found measurements of a N/A C3J cam compared to a standard turbo C1J cam, the turbo job has more lift and duration, now correct me if I'm wrong but would that turbo cam work in an N/A engine?

[Dave Reed]

As long as it fits it should offer an improvement. However you'll probably find that it will have less over lap that the n/a cam, which I think is better on a turbo motor..

I'm sure the likes of Andy and scoff will confirm :)

[youngscottie]

I think the overlap may be to short
N/a engines use overlap to aid cylinder filling
Do you have the timings to compare the two
Could always go custom

[Sparkie]

i fitted a piper N/A 285 to my old mk1 le car. - the duration of the NA 285 is actually nearer 285 than the turbo 285 ;) - nice and lumpy and rev-able :)

[Scoff]

With n/a stuff its even more important to pick the cam based on what you want the motor to do. I think you'll end up having a grind done but you won't know what you want until you decide how you want the engine to perform. After that you'll just have to mix common sense with profile vs. result data from other similar 8v engines in the hope you come up with something half decent. There isn't enough data out there for C1J n/a to decide on exact numbers.

[Os8472]

So basically the turbo cam will work but the overlap is too small :( bugger, was thinking I had a cheap fix there.

Sparkie where did u get your cam done? How much did it cost you? I was after something that would be revable so it sounds like yours would what I'm after

[SCHWARTZ]

Don't know if this helps but Volvo used a c1j mounted lengthways in the 340 and maybe in some others. They might have different cams to the c1j we all know.

[Sparkie]

So basically the turbo cam will work but the overlap is too small :( bugger, was thinking I had a cheap fix there.

Sparkie where did u get your cam done? How much did it cost you? I was after something that would be revable so it sounds like yours would what I'm after

i got piper to grind it. - i sent it off direct, with the spec and my contact details. i found an old spec sheet of NA 5 grinds.
the R5TBP285 is the turbo cam, i'm pretty sure the cam i got done was R5BP285, i.e no 'T' in there. - give em a call and ask for the spec.

[Andrew Cooke]

I don't know what you're trying to achieve, how much you want to spend, or what you have lying around, but don't write off dropping a turbo cam in if it's cheap enough. The standard NA cam is very mild (it is a shopping car, not a sports model), but if you're buying new get an NA cam cut rather than use a turbo one.

I'll bet a 285 turbo cam would work just fine as a fast road cam. But maybe if someone has a kent 200 ground at 106deg it would work better - and sound racier....

[Os8472]

Don't know if this helps but Volvo used a c1j mounted lengthways in the 340 and maybe in some others. They might have different cams to the c1j we all know.

Thought about that, the engine they used was a stock C2J, same 72bhp engine as I'm starting with


i got piper to grind it. - i sent it off direct, with the spec and my contact details. i found an old spec sheet of NA 5 grinds.
the R5TBP285 is the turbo cam, i'm pretty sure the cam i got done was R5BP285, i.e no 'T' in there. - give em a call and ask for the spec.

Sounds like it might worth a call


I don't know what you're trying to achieve, how much you want to spend, or what you have lying around, but don't write off dropping a turbo cam in if it's cheap enough. The standard NA cam is very mild (it is a shopping car, not a sports model), but if you're buying new get an NA cam cut rather than use a turbo one.

I'll bet a 285 turbo cam would work just fine as a fast road cam. But maybe if someone has a kent 200 ground at 106deg it would work better - and sound racier....

Well I'm building a C2J to give roughly 90bhp and be nice and revvy, 100bhp would be nice though :)

Basically the engine is going in my brothers triumph spitfire, they have a 1500 75bhp engine as standard that doesn't rev past 4500rpm without lunching its self cus of the 3 bearing crank and it weights a fookin ton, basically it's a crap engine. He wants something with abit of go in it to make his car a little more peppy, the C series is a considerably lighter ever, about 10kg than the C series:eek: so the weight reduction alone will be an advantage

[Tony Walker]

seems like alot of effort, why not just put a c1j in? not much more effort involved?

[Os8472]

seems like alot of effort, why not just put a c1j in? not much more effort involved?

Cus he doesn't want a turbo :confused::sad2: silly git

[SCHWARTZ]

Has he not felt the joy of boost then?:scratch:

[Tony Walker]

madness, they bring you so much pleasure every time you fix it? theres alot better engines than the c2j more readily available and after buying and getting a cam made probably cheaper too with alot more power. i know you probably know this i just cant understand :confused:

[Os8472]

Has he not felt the joy of boost then?:scratch:

I took him out in mine once, funny thing after twenty minutes of 22psi and he'd gone abit green lol

He likes turbos but doesn't want 1 on his spitfire, he's got his Alfa for going...... well I can't say fast lol

[Tony Walker]

maybe f3p engine or something. not too powerfull still 8v 1.8 bit more power efi. cheap.

[Os8472]

maybe f3p engine or something. not too powerfull still 8v 1.8 bit more power efi. cheap.

I surguested the E7J but he wants something that looks like the OE engine :rolleyes:

[Os8472]

I know what I'll do, the 9 has the same C2J engine that my bros engine will be based on, so I'll get that fixed up and running right then get it dyno'd, fit the GTT cam and get it dyno'd again and see what the effect is

[Brigsy]

Bin the cj2 idea and fit a n/a mazda rotary lump in, cheap, small revvy. Mpg not the best though lol

[Os8472]

Bin the cj2 idea and fit a n/a mazda rotary lump in, cheap, small revvy. Mpg not the best though lol

Hey it's not my choice of engine, I just gotta make it work

[Sparkie]

i almost forgot, i fitted a 1.1litre head onto the block, which took the compression ratio to approx 11.2:1.....

[Os8472]

i almost forgot, i fitted a 1.1litre head onto the block, which took the compression ratio to approx 11.2:1.....

Already got that covered, got a head off a mk1 1.2 twingo