Is there a downside to (Reground Camshaft)

[essi1553]

Having a reground cam, compared to a competitors of similar duration?

[Scallywagon]

You really have to compare cam to cam using the cam profile. Most of the time this information is not available from a reground cam.

Additionally, due to the rocker's angle, the wear on the rocker pad/cam will be accelerated and, offset.

[nando]

typically you need oversized eccentrics as well (more valvetrain weight).

I'd never personally use a regrind, but lots of people doing budget builds use them. To me though, the head is where you will make the most difference in power - best not to skimp, or don't bother at all.

[MR 325]

There's nothing wrong with using a reground performance cam. You typically do NOT need oversized eccentrics in my experience. But hey, we've only done like 60 heads with reground cams. ;) Using a reground cam doesn't mean you're skimping on power.

[nando]

it depends on how much you grind off, yes.

I'm just saying, spend the money where it matters - on the head. :)

[TobyB]

Yes, there's a small tradeoff, as the base circle is reduced.

Duration is only one of about 6 numbers that almost define a camshaft.

Given that a regrind can be had for a fraction of new, it's often worth it if you're
playing with different grinds/duration/lift/acceleration ramps/etc.

We're lucky here to have Delta Cams- they're nice, knowledgable and inexpensive.
So I run regrinds in lots of things I build- 2002 race car, Land Cruiser tow rig, 2002 street
car... because they'll make me something that's not readily available over the internets.
For cheaper.

t

[digger]

with a reground generally you don't know what you are getting. if you dont know what you are getting then how can you choose correctly?

if you have enough information to be able to make an informed choice and it is a quality job then nothing wrong at all.

minimum information would be what schrick provide, but people like catcams provide more info again which is never a bad thing.

[essi1553]

Thanks for all the honest answers, I've always assumed that a reground cam of similiar duration (i.e. 272) would have an adverse effect on idle and valvetrain wear.

I need a new head, again, don't ask. As far as price goes it seems like Ireland Engineering has the best price for a non-reground billet cam at $325. Cat cams being second at $399 from VAC.

[TobyB]

with a reground generally you don't know what you are getting

Interesting. I've had better luck getting real numbers from Delta and Isky than from
several OEM's!

But yeah, comparing 2 cams is a relatively numbers- heavy proposition...


t

[digger]

Interesting. I've had better luck getting real numbers from Delta and Isky than from
several OEM's!

But yeah, comparing 2 cams is a relatively numbers- heavy proposition...


t

specifically talking about M20 cams, if someone tells you a cam is a 280 cam what does that mean;)

[KirkerBezerker]

Nando makes a post saying one thing...

MR 325 makes one saying another...






Head explodes

[nando]

it's just my opinion. I agree with digger though, what really matters is knowing what you are getting. the advertised duration doesn't necessarily mean a whole lot..

[digger]

its a pretty vague question similar to how long is a piece of string. there will be good regrinds and not so good ones like everything else in existence.....

as for performance (hp/torque) all that matters is what the valve motion is. if a regrind can be made to produce the same valve motion then there is no difference. i cant comment on the effect of durability or whether there are bigger limitations on the profiles than can be produced as i am not informed enough.

metric mechanic cams are hardwelded by web cams in case anyone was interested

[meengreene30]

Essie, check out the 280/274 from bimmerheads. It'd go nice with a chip and #17s. If i was gonna get another one i'd get this.

[digger]

i would not use a split cam duration on a NA M20. the exhaust flow is not good enough to use a smaller duration exh. it will plateau the power curve too early in comarison to a non split cam. you gotta get that old burnt shit out before you try to get the fresh charge in