Re Alfa Romeo JTS 3.2 camshaft change question

[n2xlr8n]

I know there are valuable inputs from many more knowledgeable than I, but my primary concern in a situation like you described would be P to V clearance with cam phasers.

In ecus I've worked with using VVT or what have you, changing cams without changing the table would be fruitless, not to mention dangerous.

My .02.

S.

I've never tried to tune a cam table... but I'd think it would add a out 10x to the tuning time?

Yes- almost impossible without a (in my case) chassis dyno. I really didn't know what I was doing; I just tuned for earliest spool and area under the curve.

Luckily, I knew a guy that could give me a good reference and worked from that. I wouldn't want to try it otherwise.

S.

[integrale Evo]

It the cams in question are from a reputable company and they have been tested then why be concerned?

....but it's the "been tested" part you really want to see proof of and what other mods were part of the testing.

No, they have not been tested in this particular engine. I know there is a vast wealth of experience on the forum regarding carburetors and various fuel injection schemes but I do not recall threads about tuning with direct injection. The closest would be diesels but of course that is a bit different.

If it hasn't been tested then it's a development project and all the concerns list by others apply. You need to measure clearances, determine cam position limits and either to be certain there are no issues at the limits of any cam adjuster system. That may require pistons or modsctobthe cam adjusters.

Once that's done then you can start to talk about tuning. I assume it's a Bosch ecu but I have no idea what's available to retune it or what knowledge is out there about what needs to be tuned to keep the warnings off......or think about an aftermarket ecu.

Those cam specs are very close to what's in my frankenferrari.....ramp angle and top of the lines may be different but thos are just a couple degrees more duration and 0.3mm less lift....very close....and nothing like tame

I'm afraid they aren't a reputable company and don't know how you've come to the decision that they are the same or different spec to anything with the scant information which has been provided.
I

[mk e]

Those cam specs are very close to what's in my frankenferrari.....ramp angle and top of the lines may be different but thos are just a couple degrees more duration and 0.3mm less lift....very close....and nothing like tame

I'm afraid they aren't a reputable company and don't know how you've come to the decision that they are the same or different spec to anything with the scant information which has been provided.
I

I have no idea on their reputation which is why I said "if they are reputable"....which has am implied meaning to research them before buying anything.

The basic specs given are close to want I use. I pay a lot of attention to the seat to seat spec on 4v street motors...and it's right up at the limit of anything I would even pretend belongs on the street. To hit the given lift with the given seat duration the lobe ramps will need to be fairly aggressive as well...but as you and I both said that's only enough info to guess....but grandma's cams those ain't, no guessing about that.

[integrale Evo]

Those cam specs are very close to what's in my frankenferrari.....ramp angle and top of the lines may be different but thos are just a couple degrees more duration and 0.3mm less lift....very close....and nothing like tame

I'm afraid they aren't a reputable company and don't know how you've come to the decision that they are the same or different spec to anything with the scant information which has been provided.
I

I have no idea on their reputation which is why I said "if they are reputable"....which has am implied meaning to research them before buying anything.

The basic specs given are close to want I use. I pay a lot of attention to the seat to seat spec on 4v street motors...and it's right up at the limit of anything I would even pretend belongs on the street. To hit the given lift with the given seat duration the lobe ramps will need to be fairly aggressive as well...but as you and I both said that's only enough info to guess....but grandma's cams those ain't, no guessing about that.

I was remarking on Kevin's comment that they were, but you don't have any complete spec to look at which is why i'm questioning how you've managed to come to a comparison.
At what lift and clearance were any of the quoted figures done at? Seat to seat? At 1mm lift? With stock valve clearance? With a different valve clearance? No valve clearance? Valve opening duration? Cam duration?
You/we have no idea so there is no comparison to make. Like most European (and maybe Worldwide) camshaft manufacturers they are just that; a manufacturer, they're not designers, a lot of them do not have a clue.
When an engine comes here with them in they get given back to the customer and go on Ebay, because the general public don't know their arse from their elbow they fetch good money which is then put towards a pair of properly designed cams which aren't made from something resembling lead....

[mk e]

The website says lift at zero clearance , timing is open to close....which sounds like 0 lift, but that's not clear nor is lash as it says both zero and spec....so you're right it's not clear.