Zzak

Looking for intake and exhaust duration@0.1mm, duration@1.0mm, maximum lift, lift at TDC.

I couldn't find anything specific in the archives especially when looking to build a mild n/a 7A.

cuatrokoop

There are factory specs for lift and duration, however I'm not sure where they are specifying the duration WRT lift, and I know they don't give a lift @ TDC. I remember the cams being quite mild, low 200d duration and 9.x mm lift.

Stock 7A cam -

Intake - OBTDC - 6.0d
Intake - CATDC - 38.0d
If I did the math right, that is only a 224d duration.

Exhaust - OBBDC - 42.0d
Exhaust - CBTDC - 3.0d
Again, assuming I did math right, that is only a 225.0d duration.

Those durations would probably be comparable to the "duration at 0.1mm lift" of the CAT cam specifications.

BTW, I think anything over around 11mm of lift needs to have different lifters to take the "abuse".

Zzak

INT 10.14 X 270 @110
EXT 10.89 X 270 @110
EXT 10.89 X 270 @110

Although I've never seen it specified this way I'm thinking this is 270 duration, 10.14mm lift intake, 10.89mm lift exhaust with 110degrees between lobes. Eurospec thought this cam would idle rough but perform well top end. I'm still a little confused as the stock 7A already waits till 5k to develop power, so where would the power be developed with this cam?

TurboEnvy52

I think better cams will make more tourque down low too though.

cuatrokoop

Yes, 10.14mm lift, 270d, 110d LSA.

Get the head reworked a little and you'll get even more benefits. Most aftermarket cams retain the normal 20v driveability as far as I can tell, the torque curve may shift upward (7A makes 140+ lb/ft by ~3200rpm or something like that), and the top end will really be livened up, much more so than before.

Definately still try and do the MAF switch, and back when I was still thinking of massaging the 7A I looked into an Apex'i S-AFC controller to allow for more fuel flow. Once you add up cams, minor head work, a tweaked MAF, the S-AFC, and better injectors you'll begin to see why I didn't persue the 20v option further, but went to the 10vt. Don't get me wrong, I love the 7A power plant, infact I'd love to put one in the 5kq (I have the bits minus the tube header that I sold). But, since you don't want to go the turbo route like I am (at least not yet), I definately see why you want to mod the 7A. It'll be a fun power plant, that is for sure.

cuatrokoop

I mean, they shouldn't loose any unless the overlap is too large (going from memory). A good cam should be able to retain most/all of the stock torque/hp down low, and definately add hp up top or in the mid-range, or a little of both. Head work also comes into play there a bit too.

ddg=shinebox racing

Higher lift and longer duration kills intake velocity @ idle and low revs, causing uneven fuel mixture and poor cylinder filling, that's why your idle is so rough with rowdy cams!!!

The extreme are big "blorchy" American V8's, they have crappy carbeurators and convoluted intake manifolds, both causing poor fuel atomization and mixture (compared to F.I), making the idle horrible!!!

Zzak

to be the biggest cost in the project.

P.S. - If I could get you to do all the labor for free, then I agree the 10vt would be a much more cost effective solution =)

TurboEnvy52

ugh, another 10VT fan

Zzak

application before the end of 2005.