What Cam Shaft are available these days?
Is it really worth upgrading Cams?
How about on a stock head?

We are talking about engines with larger turbos & exhausts, latest chips & mafs ect...

I'm not a huge fan of Re-Grinds so you can at least keep the stock cam shaft for emissions ect.. unless a good used 2nd hand is found.

The only cam i know of is the Webcam 274 Grind Which is a billet piece not a regrind. Anyone have experience with this cam?

I know JME had a list of cams but no longer in business/ retired?

 

Paulyy, you can get proper billet cams but I think on your car with that turbo and head, for now, you're better off with stock cam (maybe n/a). It will only move things over to the right even more and you won't enjoy the car for what it is. Having run both I think you're better off trying to keep the torque where it is for now. imho.

 

Thanks for your input Patrick!

Yeah I'm not really looking to do head work since it'll cost $3-4k and for that money i could get a 968 long block and work that up mildly for 6k

 

A cam will definitely help with top end power...but I think its safe to say these engines do not like to be revved over 6000.

When I got my first 951 5 years ago, I was coming from racing 4g63 engined mitsubishis... So getting full boost at 4000 wasnt a problem because you were revving to 7500+. After treating my 951 the same way, I spun a few rod bearings. Never so badly I couldnt swap in a new bearing set without removing the engine, but enough to teach me a lesson.

Keep the rpms under 6k, and enjoy the torque in the higher gears between 3500 and 6000. I havent spun a rod bearing on these engines in years.

As for the head, next time you swap a headgasket, take the head apart,clean up the intake ports with a dremel, and polish it to a mirror finish with sandpaper. Thats about as much time as I would waste on these heads. If I wanted anything more, id look into swapping a twin cam head onto the engine.

 

Paulyy head work is 3-4K DAM its cost 3-4 hundred for head work here lol thats sucks. if you dont have head work then its useless getting a cam. maybe a NA cam will work

 

I think he means having the head ported maybe not just rebuilt?

Does the N/A cam make a difference at all?

 

I had the head rebuild with new springs, cut valves, ported, and minor polishing and he went over the both surfaces to clean it up since it was already straight.

 

The n/a cam does help a bit, I think it has more duration on the exhaust lobes.

3-400 is extremely cheap for all the work you had done, definitely a bargain, but I wouldnt consider that a typical price. Something like that should run 700-800 at your average shop. I know that I would charge someone at least $200 for minor porting and polishing, and that doesnt include pressing in new guides and lapping valves. And he shaved the head?

Where is this guy who did the work? Considering theres about $125-$175 in parts alone there, it would pay for me to send my head to him as well.

 

I was talking about new valves + springs, porting, polishing, flow matching ect, the works.

My head has been refreshed, it had some marks in it which got filled up and machined flat. the valves got cleaned up, new guides, and polished up the intake chambers and i think slightly opened up.

Plus prices down here for jobs like that isn't as cheap. like i said id rather buy a 968 long block and get forged rods and pistons for the money i would spend on a decent amount head work.

 

I got all that plus lash caps minus New valves for less than a thousand. i got JM ti spring and retainers

We will see in a few if it was all worth it.

 

Paulyy, you could get a cheap head out of the US and have it worked as mentioned above...but then what about the i/c, i/c pipes, throttle body, intake, headers, exhaust...I'm of the opinion that if you're going to modify the VE of a particular part then it will probably highlight the stock nature of another part. Maybe create a bottleneck. To do everything is an expensive project. There's possibly ways of increasing the flow of some parts to your advantage, but I'm not sure that there is quantifiable proof to say what to do to which parts?

 

You don't need headwork to compliment a cam, unless it's such an aggressive cam that peak power is realized north of 7,500 RPM, which, of course, means you need to change a whole lot of other things, and that's not the point here.
No, but what is important to accommodate a cam properly is the ability for the exhaust to exit the engine as best as possible. Pre-turbo, post turbo, and of course, the hotside, should all do the job.
Don't assume that if you have a big turbo that you're good to go. You should measure the back pressure.
Do all this right and there's a very noticable difference in power, given the same boost. You can also safely increase the boost a tad bit, because the dynamic compression is reduced a little.
Midrange torque will not be affected (can even be enhanced) if you don't go too aggressive. The only downside is noticably more slugish off the line (as if our cars aren't already slugish enough down really low), not a smooth idle (if you care), alot less vacuum at idle, a little less gas mileage (if you care), sometimes harder to start.

I talked to Jon Miledge within a year; he was in business.

 

Pat,
Well on my motor.. the bottle necks are head, intake and throttle body, possibly the headers and x-over. i can't really think of or see any thing else.
We'll you've got a point, if i get my head worked but then the intake can't flow the required air to see the gain i put into the head.

Tommy, I haven't measured back pressure yet but i guess i should. i don't expect it to be dramatically high at all since i am running a proper GTX series turbo with a .82 a/r

Hm http://www.jmengines.com/index.htm Dosn't work any more or he must have stopped doing some things.

 

Lee didn't u spun a bearing least year or something. I would post the thread but I can't search on the dam pos iPhone

 

No, I didnt spun a bearing last year. In february of 2010 I removed my engine to reseal it, upgrade the clutch... and I found a few other problems.

1. The turbo had a chipped blade

2. The crankshaft had too much end play. As a matter of fact, when I had my first engine problem I sent the crank to one of the best crankshaft shops to repair it. The problem was the crank was missing material where the thrust bearing would go, so I had it rectified and problems were solved...for a while. When I pulled the pan off of the engine, I found all the chunks of the "rectification" siting at the bottom of the pan.

If I knew this was going to happen 5 years ago, I would have just bought another crankshaft....

So in the last two months ive been really busy. I swapped a 911 3.4 engine into my boxster, built a really nice 930 for a customer, and at last the engine is finally on an engine stand in my shop, waiting on some rebuild parts. I was going to do a twin cam conversion, but after talking to a few people who really know, its too much time and money to do right. Im going to post a thread on it soon, I spent a lot of time installing a lot of fiber glass parts, and painting it rosso corsa red...

sorry to hijack