Talk to me about cams :)

Post by **Lude-dude** » Thu Mar 29, 2012 2:38 pm

I was bored and did a thread comparing cams:

http://www.ludegeneration.co.uk/honda-p ... -t742.html

um skunk2 mani, and now modified dc sports exhaust mani to 2.5"

crower cams, crower valve springs, retainers de coke & new piston rings, 8lb flywheel

the idle is very lumpy, but dont seem to bother me when I know its supposed to be like that, never stalls out, maybe bit on startup

got AEM FPR & skunk2 68mm TB to go on, see what that gets me hopefully that will be the end unless I get some higher comp pistions one day

Post by **Merlin** » Thu Mar 29, 2012 4:51 pm

Some info Taffy wrote on the subject when he was building the start of what is now Dino's car.

Taffylude wrote:Cams & Valvetrain

There are numerous manufacturers of cams available for the Lude, and there doesn't really seem to be any ONE type that is thought of as better than the rest. They range from mild performance to extreme, but for my build I just wanted a good 'road use' set that would give good gains for a daily driver, without causing a really lumpy idle etc.
I narrowed the choice down to OEM Prelude Type-S Cams, Crower Cams or Skunk2 Cams. Both the Crower and Skunk2 cams also offered three different 'stages' of cam in their range, from mild to race applications.

Type-S Cams
The Type-S cams were appealing due to them being OEM quality, and obviously being a tried & tested reliable part in the Prelude Type-S. However, the point of this project was to push the boat out a little bit and see exactly what I could extract out of the H22 engine, so I was tempted to go for some of the higher performance aftermarket cams, especially with them being similar prices!

Crower Cams
Crower have a good name for camshafts, despite a problem they had a few years back with camshafts snapping due to weak cores in the steel. They now offer 20% stronger cams which have had good reviews from Prelude users. They also offer the full Crower valvetrain to suit their shafts on their website.

Skunk2 Cams
Skunk2, despite having a bit of a name for 'mass produced' engine components, do specialise in camshafts, and offer a very good range of internal engine components for the H22. Also, they have recently released a new range of 'Pro Series' camshafts, which seem to be creating a bit of a stir in the tuning scene due to their solid power gains.

In the end, it just came down to personal choice. I'd seen a dyno graph posted up showing the Type-S cams v's Skunk2 Stage 1 v's Skunk2 Stage 2's, and the Skunk2 setup seem way in front. If the standard Skunk2 Series 2's were showing good power, I was curious just what I could get with the Skunk2 Stage 2 Pro's! I therefore opted for:

>Skunk2 Stage 2 Pro Cams
>Skunk2 Duel Valve Springs
>Skunk2 Titanium Retainers
>Skunk2 High Compression Stainless Steel Valves

(Graph shows WHP)

http://preludeuk.forumup.com/viewtopic. ... =preludeuk

JayJay · Post by **JayJay** » Thu Mar 29, 2012 4:54 pm

Yeah, Taffys thread is brilliant for those looking at NA, he really goes in to a lot of depth

judderod · Post by **judderod** » Thu Mar 29, 2012 5:06 pm

I have JUN's. Idle exactly like stock, although they valvetrain noise is a little louder when cold due to the high lift VTEC lobes.

IMHO they're by far the best option for street. The low end torque is better than stock, and in VTEC is just bonkers. But they cost too much.

Don't forget you'll need uprated springs and lightweight retainers if you want to rev high, which you need to on some cams because that's where all the power is.

JayJay · Post by **JayJay** » Fri Mar 30, 2012 10:09 am

Ah yeah JUN I forgot about then

They did do FRM-compatible pistons but the newer ones (from quite a few years ago I mean) AREN'T, just FYI

judderod · Post by **judderod** » Fri Mar 30, 2012 10:35 am

Mahle used to make them for JUN. Then they copied them and sold them under the Mahle name. JUN got pi$$ed and moved to a different manufacturer.

Post by **Merlin** » Fri Mar 30, 2012 11:29 am

Im not planning on aftermarket pistons since the a7 has fairly high comp already. A nice list of head parts here:

http://realstreetperformance.com/store/ ... f5198df9b9

JayJay · Post by **JayJay** » Fri Mar 30, 2012 12:00 pm

judderod wrote:Mahle used to make them for JUN. Then they copied them and sold them under the Mahle name. JUN got pi$$ed and moved to a different manufacturer.

Cosworth now isn't it? But that explains why Mahle are the only manufacturer of FRM-compatible pistons! Didn't kow they made them for JUN

Merlin wrote:Im not planning on aftermarket pistons since the a7 has fairly high comp already. A nice list of head parts here:

http://realstreetperformance.com/store/ ... f5198df9b9

I know, but it's useful info anyway

It's about £1600 for Skunk2 valves (standard compression), valves springs, retainers, cams (Pro 2) and cam gears by the way. This is brand new from Skunk2.

Duo · Post by **Duo** » Fri Mar 30, 2012 12:14 pm

Just as an FYI for you guys, when I looked into a supercharger build I hit upon Porsche pistons, some of those boxers have FRM like liners and suited pistons for turbo applications. I never looked into sizes but might be worth a look if you're after saving some money, or possibly get a company to make you up a set of slugs out of something like titanium but that would probably be major $$$. I've not looked thorougly into it though so other than the FRM being rather hard I don't know why there aren't some pistons you could use on the open market, anyone shed light on this? Is it a chemical bond issue causing problems, how hard FRM is or both?

judderod · Post by **judderod** » Fri Mar 30, 2012 12:45 pm

AFAIK Mahle make Porsche's pistons, as they're the only manufacturer in the world that make forged pistons that work in FRM.

Performance pistons are often made of a forged alloy which galls and scuffs FRM over time as it's softer (with the exception of Mahle Gold series as they coat the piston skirts with a teflon-like later). However being softer makes it less likely to shatter and crack and hence it can withstand slightly more detonation (abuse). Stock Honda pistons are cast IIRC and use a tougher alloy containing more silicon so it doesn't grab the FRM walls.