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?

 

[Andyquadra]

Well piper don't stock blanks, and won't release any lobe spec info to further my calcs. Seems the only way is to send my cam to them to confirm how hot they can get it. I've already mentioned the 276 specs isn't what I'm looking for and I'm pretty sure that whichever way they can get closer to what I'm after is going to be a trade off for something else. Or they'll supply a billet to exact specs for £900ish.
Catcams, I think the billet prices are cheaper but only if produced to existing specs. Out of the 11 listed (seems there 2 lists??) there's only 2 useful for turbo cars, with the better one being the #606. Still not ideal, but it's pretty good.
Since its looking like a regrind I'd like to measure up the std cam again and @Turbjj if you could do the cup if I can't find the specs. But what other versions of the j7r is there? 2lr 8v n/a, 2.2ltr 8v n/a, 2ltr 12v n/a, 2ltr 8v turbo??
I'm willing to measure up any I can get my hands on.
@DaveL485, did you mention you'd gone Catcams for the 12v motor? Any details?

you will probably find a lot more meat on a N/A cam, but the overlap wont suit a turbo application I guess

 

[Haz]

Yes, but the meat may allow more lift, more lca, more lsa which will reduce overlap. Or it may not haha.

 

[Andyquadra]

Yes, but the meat may allow more lift, more lca, more lsa which will reduce overlap. Or it may not haha.

be worth trawling ebay for a scrap N/A 8v engine just to measure the cam

 

[Red21]

Try Kent cams, l have one in mine and a new item ready for my gen ll engine build. I have no actual specification details for it yet but the box indicates 277.

 

[Haz]

I do have a nosey every now and again, but if anything crops up at local scrapyards etc please let me know.

Are they both the same cams @Red21? Regrinds again? Sure they'll have basic stats on their site and I can work the rest out.

 

[Haz]

Nothing listed for the 21 on kent cams. Same for piper, so I assume it's a regrind from std. Can't see it being much different than the piper 276 tbh.

 

[Turbjj]

Well piper don't stock blanks, and won't release any lobe spec info to further my calcs. Seems the only way is to send my cam to them to confirm how hot they can get it. I've already mentioned the 276 specs isn't what I'm looking for and I'm pretty sure that whichever way they can get closer to what I'm after is going to be a trade off for something else. Or they'll supply a billet to exact specs for £900ish.
Catcams, I think the billet prices are cheaper but only if produced to existing specs. Out of the 11 listed (seems there 2 lists??) there's only 2 useful for turbo cars, with the better one being the #606. Still not ideal, but it's pretty good.
Since its looking like a regrind I'd like to measure up the std cam again and @Turbjj if you could do the cup if I can't find the specs. But what other versions of the j7r is there? 2lr 8v n/a, 2.2ltr 8v n/a, 2ltr 12v n/a, 2ltr 8v turbo??
I'm willing to measure up any I can get my hands on.
@DaveL485, did you mention you'd gone Catcams for the 12v motor? Any details?

I could try, but i'm not a cam specialist...
I have a techniprofile stage 1 or 2 in my engine, just put it in, set the clearences and it worked... Did the same now in the new engine with the cup cam, but did not try yet, it's still on the engine stand and i did not start on the loom for the adaptronic yet. Left the adjustable pulley like it was for now, and i'll see later on.

You could check with techniprofile, they seem to have several different stages, as far as i know, their stage 4 is near to the cup cam. French big power builders use them.

 

[Turbjj]

Also R21 gtx cams seem to be used in france.

 

[Turbjj]

http://arbreacamestechniprofil.pagesperso-orange.fr/techniprofil-arbres-a-cames-anglais.htm

 

[Haz]

Thanks. Usually you need a vernier to dial the cam in to the manufacturers setting, using a std pulley and timing normally the cam may be out by a few degrees unless the lsa and lca are the same as std.
I'm finding it hard work contacting the cam engineers as you can't speak to the person who can go into detail about a new spec.
I'll google techniprofile as see what I can find. I've had my head buried in maths and formulas for days to work out exactly how I want it and yet to come across anything near that warrants spending on, either that or I'm getting it completely wrong haha.

 

[Haz]

http://arbreacamestechniprofil.pagesperso-orange.fr/techniprofil-arbres-a-cames-anglais.htm

Hmm, seems to be just a page to contact them? You can't search and see specs.

 

[DaveL485]

@DaveL485, did you mention you'd gone Catcams for the 12v motor? Any details?

Yes. Details? It was fucking expensive. £749 expensive.
Split duration 275°/264° with 11mm lift at the valve. 105° peak angle.

 

[DaveL485]

There was 1965, 1995 and 2165cc versions of the J7 (J7R or J7T for the 2165), fitted to the 21, 25, Safrane, Master, Espace and so on, a few Peugeot's and Volvo's too I think.
Of those the 1995 and 2165 had 12v versions (R21 and 25 TXi for the former and Safrane VI Executive for the latter are 2 examples)

 

[Haz]

Yes. Details? It was fucking expensive. £749 expensive.
Split duration 275°/264° with 11mm lift at the valve. 105° peak angle.

My design is looking that way too!
Is that your own design?
Do both valves lift 11mm?
Both lca at 105?
So the timing is 32-63/57-27?
Lsa of 105?
59* overlap?
What's the lift at tdc?
Unusual design that, I would have thought for nitrous you would have needed the duration the other way round and a much wider lsa?

 

[Haz]

There was 1965, 1995 and 2165cc versions of the J7 (J7R or J7T for the 2165), fitted to the 21, 25, Safrane, Master, Espace and so on, a few Peugeot's and Volvo's too I think.
Of those the 1995 and 2165 had 12v versions (R21 and 25 TXi for the former and Safrane VI Executive for the latter are 2 examples)

Is the 2.2 the same bore but longer stroke? And the 1.8 shorter?
Let's ignore the 12v version for now as the double valve will have odd lift and duration.

 

[DaveL485]

Is the 2.2 the same bore but longer stroke? And the 1.8 shorter?

The 2165 was longer stroke, both 88mm bore but 82 to 87 stroke.

The 1965 I don't know I have never seen one or bothered to find out what the difference was lol

 

[Haz]

And your cam?
Interesting. I'd assume the 1.8 is just less stroke again so ideal for a revvy motor. Are the heads the same?
So the 2.2 cam will go in, just depends on its specs if it's any use, in theory it will have more lift and duration but probably lower lsa.

 

[DaveL485]

I'd assume the 1.8 is just less stroke again

1965cc not a 1.8 mate. It's only 30cc different.

 

[Haz]

Just mulling your cam over again, I know I need a life!
I would have thought that the lca's are different. I recon the exhaust lobe is advanced giving at least 115* btdc, which would change to timing to 32-63/67-17 and overlap of 49*.
If you then give the cam 4* retard so timing is 28-69/65-21 you end up with still 49* overlap but due to lobe design the lift at 1.0mm tdc should be lower.

 

[Haz]

Ah yeah, dur ! Presumably in piston crown design and higher cr then.