Tbred911

I'm contemplating installing camshafts offered by FVD (along with their ECU adjusted for these cams...) and here are the specs....

Inlet Cams:
Cam lift (Valve Lift) I/E (mm) = 10.7 mm
Duration°/Peak Timing = 280°/127-102°
Valve Timing °CRA (IO-IC-EO-EC) = 13-87 38-62
Valve Lift at TDC I/E (mm) = 0.4-3.2mm
Outlet Cams:
Cam lift (Valve Lift) I/E (mm) = 10.7 mm
Duration°/Peak Timing = 272°/113°
Valve Timing °CRA (IO-IC-EO-EC) = 69-23
Valve Lift at TDC I/E (mm) = 1.5mm

Does anybody know what this set of cams will do to the power curve? I don't know what the values mean and if they take away much low end torque for higher rpm gain I don't want them...

ideally you just want to raise the torque curve on all the current rpm points... maybe shift it a little to the right (say 500 rpm max.. but that's it) to retain the stock character and driveability with more oomph...

has anybody installed these or have any thoughts on this setup?

redridge

who is going to do the build?.... I would also look into the x51 setup for the 3.4 just for informational purpose. It a $17K option with an increase of 25hp.

Tbred911

not interested in spending $17K for x51 .... just want to do camshafts + ECU... MUCH cheaper ~ around $3,600 for cams and FVD ECU (roughly.... not including labor) no way I'm spending $17K... heck for that amount of money I could take it to Jake Raby and build a super motor over what I have right now.... ! cost is a constraint here...

redridge

Im not saying that you should spend $17K... what Im saying is, the x51 kit (from memory) had cams, plenoms, heads.... etc.... a lot more than just cams, and gained only 25hp for all that work. I guess what Im saying is you won't really notice to much power improvement for all the work with the FVD setup.

jrgordonsenior

You could just advance the stock cams a little and compare before and after dynos.....

Tbred911

ok cool

Tbred911

that's a fair bit of work as well and then there is tuning... how do you tune for a stock advance cam setup... just want to see if anybody has done these cams their feedback... I know you'll get more power just trying to figure out what you'll lose ... totally unfamiliar with cam setups... just looking for something that's proven that works well... I don't want to rely on a shop around here to tune things and see what happens... I guess I'm looking for a good total solution...

logray

I read somewhere someone tried to install them and it was a nightmare IIRC (learning as they go).

I think unless the shop has experience doing this before or other mods compliment it, I would save the money and spend (or save) it otherwise.

NZ951

A radical enough cam will raise peak power well above 25HP.

NZ951

As a general comment, the cam specs seem reasonably tame. I dont have experience with cams in Porsche motors but do in others. So keep that in mind. I think the duration is basically on a light race / sports side, and the lift similar. I have 288 intake and exhaust cams in my race car, but others do go over 300 degrees to put that into perspective. I have 10mm lift on both as well.

You will probably find the cams are a little bit lumpy and may need to raise the idle slightly, you will also need to set the valve clearances etc, so may as well do a valve job and stem seals while there, which means you might as well do the seats and porting... then you really need the intake and exhaust length and design changes to be tuning to the resonance change and rpm that peak power will be made at. So cams really become a bit of a nightmare in terms of other stuff that makes sense to do, you dont just bolt them in, throw in a tune and away you go.

If I ever do any mod to mine, which I really dont see the point in the bang for buck isnt there, I would just turbo it, pretty cheap bank for buck (if you dont get conned by a tuning shop off the shelf "kit").

Pac996

Could be something like a bike I bought stock from the factory with a 1000cc engine putting out 170hp. I wish the 911 was just 150hp per 1000cc. You can think putting a cam in is going to improve things but the engine might need bigger valves or more space for the cam lift so that you don't self destruct the valves into the pistons.

I hope there is somebody thats raced different cams and has had some experience with the cam you are lookng at. You could just be losing low end by increasing the duration and having the power mostly available around top end. Engine is pretty nice the way it is already.

Tbred911

FVD says the sams will swap in and as a precaution I would also install titanium valve springs.... they told me *not* to port and polish as there is a need for turbulent air to mix things up... they said porting and polishing may result in loss of horsepower using this specific engine and installing these cams only. As for getting conned this is why I'm doing the research here.. trying to find somebody who has done it and undestand what kind of powercurve it yields...

drbooba1

You will really need to know what you have first. If the cams do not violate smog laws then they( FVD) have
more than likely increased the duration 5 to 10 degrees and made the lift curves match, it is a hydraulic cam so the ramps aren't being brought into play. I do find it interesting that the exhaust has "Valve Lift at TDC I/E (mm) = 1.5mm" while the inlet at TDC is" Valve Lift at TDC I/E (mm) = 0.4-3.2mm" but I see now
that I posted it you probably transposed the 3.2 / .04 that being said it probably makes sense. If the cams are Schrick and they probably are they are well made and engineered. But still you would need to know the stock numbers and compare them, so do that first.

regards

logray

Dug this thread up regarding the FVD cams:

https://rennlist.com/forums/996-foru...e-problem.html

trendy996

My experience from putting cams into a Audi 1.8t engine using a variocam design lost power due to the different cam timing values the cams are creating. It will cause the ecm to pull timing. Therefore a tune is a must.
Flat6 has sport cams for much cheaper btw.