Camshaft choice

ALVO360

I have an A cam and a VX3 cam that I can't decide which one to go with. it will be going into a B230 turbo with the 531 head and larger exhaust valves, chips with a 7,000rpm redline.

I only really ever rev to 6000rpm anyway and this car is not used as a daily driver, just a weekend hoot-about. Anthony Hyde says the VX3 cam is his favourite Volvo cam, yet many others claim they prefer the A cam? Just keen to hear thoughts on each before I drop one in.

ramrod

The camshaft won't affect crankcase pressure. It's above the head

Where are the leaks coming from?

ALVO360

ramrod
The camshaft won't affect crankcase pressure. It's above the head
Where are the leaks coming from?

The reason I'm suspecting the camshaft is because I had excessive crankcase pressure with my old cam. It would leak from the oil fill cap, front crank seal, sump, valve cover and PCV/flame trap. Since replacing the T3 cam from classicSwede with the IPD turbo Cam, the front crank seal no longer leaked, the oil cap no longer leaked and the PCV/flame trap no longer leaked. So changing the cam appeared to reduced crankcase pressure in this case. Others have reported issues with high Crankcase pressure after swapping cams and I have first hand experience with my cam causing higher crankcase pressure.

I believe this had something to do with the timing of the intake valves closing (half-way through the compression stroke for the T3 and 1/4 of the way for the IPD turbo cam). I understand the cam typically won't lead to excessive crankcase pressure, as it's a result of blow-by. However, my theory is that cylinder pressure is higher when the piston reaches the upper portion of the compression stroke. For the rings to seal effectively they need cylinder pressure to expand them into the cylinder walls. If the expansion of the rings is happening later in the compression stroke than it should or typically would with the factory cams, then enough pressure is allowed to bypass the piston rings before they expand and seal effectively - resulting in blow-by that may not occur with the factory cams due to timing and/or duration.

^^^With that out of the way^^^ have you had experience with both the A cam and the VX3 cam, and do you have a recommendation for one over the other?

alphax

ramrod
The camshaft won't affect crankcase pressure. It's above the head
Where are the leaks coming from?

FYI - A camshaft can and will impact crankcase pressure, in terms of evacuation of the pressure. A stock PCV system uses relatively small diameter hoses and fittings - but they are aided in a big way by strong engine vacuum. When a camshaft is fitted that significantly reduces that vacuum, the little factory system may not keep up, leading to oil leaks. Add forged pistons with more piston to bore clearance and this will in-turn lead to more blow by and the problem is further compounded.

@ALVO360 I wouldn't give up on your big cam dreams, unless you want to daily the car. I'm sure you could find a way to increase the factory engine breathing by adding some breathers to the rocker cover or elsewhere, no? Pretty common thing to do on modified engines with already marginal breather designs. Usually weld a couple of fittings onto the rocker cover and run some large breather pipes into a catch can, then vent the catch can to intake duct.

ramrod

What you're talking about has more to do with the piston rings than the timing of the valves opening and closing.

If a certain cam allows for more filling of the cylinders due to higher lift and longer opening times, then this will add to excessive crankcase pressure "IF" you happen to have worn out compression rings and oil rings.

Have you done a compression test? Have you changed the oil trap? If so how long ago?

On one of my cars, I had a leaking rear crank seal, I had no records to show the oil trap had been replaced. I installed a new oil trap, oil trap o-ring, flame trap kit (flame trap, flame trap housing and flame trap housing hose) as well as the hose from the flame trap housing back to the intake. After about 1000 kilometres and an oil change, my engine no longer leaks. Also don't bother cleaning your old oil trap, it cannot be done effectively and by the time you finish what you thought was cleaning a blocked oil trap, you would have replaced it with a new one. They're cheap too however don't buy an aftermarket one as sometimes the top lid can break and come off due to poor gluing. Genuine oil traps shouldn't have this problem.

ALVO360

ramrod
What you're talking about has more to do with the piston rings than the timing of the valves opening and closing.
If a certain cam allows for more filling of the cylinders due to higher lift and longer opening times, then this will add to excessive crankcase pressure "IF" you happen to have worn out compression rings and oil rings.
Have you done a compression test? Have you changed the oil trap? If so how long ago?
On one of my cars, I had a leaking rear crank seal, I had no records to show the oil trap had been replaced. I installed a new oil trap, oil trap o-ring, flame trap kit (flame trap, flame trap housing and flame trap housing hose) as well as the hose from the flame trap housing back to the intake. After about 1000 kilometres and an oil change, my engine no longer leaks. Also don't bother cleaning your old oil trap, it cannot be done effectively and by the time you finish what you thought was cleaning a blocked oil trap, you would have replaced it with a new one. They're cheap too however don't buy an aftermarket one as sometimes the top lid can break and come off due to poor gluing. Genuine oil traps shouldn't have this problem.

Look man, I appreciate your input regarding the crankcase pressure, but that wasn't why I started this thread. It was to obtain advice about which cam performed better, the A cam or the VX3?

I asked you if you had experience with either cam and you don't even care to respond to that.

You did a similar thing when I was asking if anyone had an IPD turbo cam to sell by replying with www.ipd.com (which wasn't even the correct web address).

I have a freshly built b230fk, with new pistons, rings and of course my PCV/flame trap is brand new. The only reason I posted about the crankcase pressure was so people could understand why I want to test an A cam or VX3 cam. It only takes a couple of hours to swap the cam over, but if I am to leave one in there, I'd prefer it to be one that will give me the most benefit for my application.

I'm not interested to have a debate about crankcase pressure, I only want to know what people's views are about the cams.

Major Ledfoot

I could be wrong about this (probably am) but I'd be reluctant to use a VX3 cam on a turbocharged engine.

It seems to me that suitable turbo cams are somewhat less 'wild' than their high performance NA counterparts.

There's an ongoing thread on Turbobricks where one guy in the USA is gradually doing comparative measurements on a wide range of cams for the redblock SOHC engines, link below.

https://forums.turbobricks.com/showthread.php?t=337956

So far, he's measured the A, B, D, H, K, M, T, and V factory cams, along with a number of aftermarket cams, including an iPD version of the VX cam. Since all the measurements are being made from the one source, it's a great guide to make direct comparisons.

The VX3 cam was fitted to the B230FB engine, which (I understand) also had a 531 head. According to the "New Car Features" Greenbook which details the introduction of the B230FB, it wasn't put in USA market vehicles.

ALVO360

Major Ledfoot
I could be wrong about this (probably am) but I'd be reluctant to use a VX3 cam on a turbocharged engine.
It seems to me that suitable turbo cams are somewhat less 'wild' than their high performance NA counterparts.
There's an ongoing thread on Turbobricks where one guy in the USA is gradually doing comparative measurements on a wide range of cams for the redblock SOHC engines, link below.
https://forums.turbobricks.com/showthread.php?t=337956
So far, he's measured the A, B, D, H, K, M, T, and V factory cams, along with a number of aftermarket cams, including an iPD version of the VX cam. Since all the measurements are being made from the one source, it's a great guide to make direct comparisons.
The VX3 cam was fitted to the B230FB engine, which (I understand) also had a 531 head. According to the "New Car Features" Greenbook which details the introduction of the B230FB, it wasn't put in USA market vehicles.

What a great resource. I really like that they've factored in the valve clearances when assessing actually duration. A lot of time and effort has gone into this spreadsheet and I appreciate you sharing this.

The A cam appears to be the winner as far as all-round performance goes. I think you're right about the VX3. There's mention about it having shorter exhaust lobe duration, which isn't as good for turbo applications.

I'm still very open to hearing the experiences from those who have run both in a turbo application.

Thanks for you input @Major Ledfoot

ramrod

Then why on earth would you say: but I just want to swap the cam for a factory Volvo cam to see if it lowers the crankcase pressure/oil seeping issue I have.

Why say the two are related then backpedal and say something completely different? What confusion

You need to have a proper plan set out with proper and clear intention for example: Test the different cams yourself because people's opinions will be different with each person and to your own

And you're right, I'm sorry about the mix-up with the IPD website address. I should know better

ALVO360

ramrod
Then why on earth would you say: but I just want to swap the cam for a factory Volvo cam to see if it lowers the crankcase pressure/oil seeping issue I have.
Why say the two are related then backpedal and say something completely different? What confusion
You need to have a proper plan set out with proper and clear intention for example: Test the different cams yourself because people's opinions will be different with each person and to your own
And you're right, I'm sorry about the mix-up with the IPD website address. I should know better

Ramrod, the post is titled "camshaft options". The first sentence "I have an A cam and a VX3 cam that I can't decide which one to go with".

I just wanted to test. As we have discussed, the change from my T3 cam from classicSwede to the IPD cam has absolutely reduced crankcase pressure.

My post was directed at camshaft opinions. You chose to focus your attention specifically on my crankcase pressure. I agree, the post is a little confusing relating to my intention of swapping the cams, but my questions were not.

Daniel @nugget_940 shared his experience on my build thread stating when he installed his Catcams on his B230 he had excessive crankcase issues. Reinstalling the factory cams solved his problems.

Laurie also shared some experience with cams causing crankcase pressure.

I have just shared my experience with you that the previous cam I had caused excessive crankcase pressure. You have been hellbent on making this about the crankcase pressure and not the camshaft preference.

As I said to you:

"I appreciate your input regarding the crankcase pressure, but that wasn't why I started this thread. It was to obtain advice about which cam performed better, the A cam or the VX3?"

And again...

"have you had experience with both the A cam and the VX3 cam, and do you have a recommendation for one over the other?"

How you interpret and respond to my post, is your choice.

If I want to seek opinions on certain camshafts, that's my choice.

You seem to be willing to offer your opinion on everything except the camshaft differences. I do understand and see why you mentioned the crankcase pressure. I do understand that my stated intentions could be a little confusing, but when I attempted to pull the conversation back to the camshafts, you continue to ramble on about the crankcase pressure. STOP!

I will edit the original post to make it clear as to what I want to know. Even though my post was centred around camshaft options and seeking opinions from those who have had experience with both the A cam and VX3.

ramrod

That's better.

It is my natural instinct to try and solve problems first then worry about modifications. Which is why when your question contained a crankcase pressure problem I focused on that. But alas, there's no need to cry like you have a bee in your bonnet; we're grown ups. You certainly wouldn't act like this in person, so why do it online?

To answer your cam question, I have only had experience with the VX3, I cannot compare it to an A, best you decide for yourself, someone here will have one. It's a personal thing that no one else can decide for you

ALVO360

ramrod
That's better.
It is my natural instinct to try and solve problems first then worry about modifications. Which is why when your question contained a crankcase pressure problem I focused on that. But alas, there's no need to cry like you have a bee in your bonnet; we're grown ups. You certainly wouldn't act like this in person, so why do it online?
To answer your cam question, I have only had experience with the VX3, I cannot compare it to an A, best you decide for yourself, someone here will have one. It's a personal thing that no one else can decide for you

You're a fool mate. You don't know me or how I would act to you in person, so let's not pretend you do. I wasn't asking for you to solve my problems, I was asking for views on the cams. You have interpretation issues, and as far as I'm concerned, you're a waste of energy.

ramrod

ALVO360

Feel free to give yourself an upper-cut at any time ?

Roinik

I'll just leave this here.

https://youtu.be/3juaQvrlsZw

ALVO360

Roinik
I'll just leave this here.
https://youtu.be/3juaQvrlsZw

? Great skit.

Samman88

Every volvo forum has its John V, however he did have a lot of useful info.

I ran an A cam on a plus T a few years ago and it was pretty well mannered. A bit of chop at idle but it wasn't as rev happy as the K cam I have in there now. Perhaps the extra overlap of the A cam compared to the VX3 might help with the high cylinder pressures you seem to be experiencing. Does classic swede give a spec sheet with his cams? And are you still running mineral oil?

ALVO360

Thanks Sam, please disregard the crankcase pressure.

Have you run the VX3 cam in your +T or another turbo motor? As for the behaviour of the A cam, you say that it wasn't as rev happy as the K... Do you remember at what RPM you noticed the power would drop off?

ALVO360

Thanks to Dave @pigdog for sharing this with me. Thought I'd put it here for others:

http://forums.turbobricks.com/showthread.php?t=218680

Samman88

That post is inline with my experience of the A cam, even with a manual it didn't want to rev out past 6k.

volvodriverman

Samman88
That post is inline with my experience of the A cam, even with a manual it didn't want to rev out past 6k.

Agreed A cam is done by 6k in my experience too. I found the V to be the best stock cam for a b23et & 15g if that's in any way helpful.

ALVO360

alphax
https://ozvolvo.org/discussion/comment/178026#Comment_178026
FYI - A camshaft can and will impact crankcase pressure, in terms of evacuation of the pressure. A stock PCV system uses relatively small diameter hoses and fittings - but they are aided in a big way by strong engine vacuum. When a camshaft is fitted that significantly reduces that vacuum, the little factory system may not keep up, leading to oil leaks. Add forged pistons with more piston to bore clearance and this will in-turn lead to more blow by and the problem is further compounded.
@ALVO360 I wouldn't give up on your big cam dreams, unless you want to daily the car. I'm sure you could find a way to increase the factory engine breathing by adding adding some breathers to the rocker cover or elsewhere, no? Pretty common thing to do on modified engines with already marginal breather designs. Usually weld a couple of fittings onto the rocker cover and run some large breather pipes into a catch can, then vent the catch can to intake duct.

Because the 360's B230ft conversion requires the use of the 360's sump, which has it's own dipstick port, I have decided to take advantage of the dipstick port in the block and use it as an additional breather. I've ordered some 12mm hose and a check valve, and just need to figure out how I'm going to run it to my Catch can.

I have also just setup my home-made oil fill cap breather.

Where it says flame trap, It should really say PCV/oil seperater.

I still have concerns that the setup I have will still be limited/restricted (as you suggested) by the small port size on the turbo intake pipe and catch can and I may benefit from installing a second port on my intake pipe and/or running a catch can with multiple ports for venting, or even a second catch can if I can't keep the pressure down.

Another reason I wanted to test a factory cam was compression.

My T3 cam reduced cranking compression down to 100psi!

The IPD cam raised cranking compression to 140psi.

I still feel this is a bit low and it was evident that the intake valve closing later in the compression stroke was the cause of this. The T3 cam wasn't closing the intake valves until half-way through the compression stroke. The ipd turbo Cam doesn't close the intake valve until 1/4 of the way through the compression stroke, which I still feel is several degrees later than it should.

If I can't get the crankcase pressure down with the above setup running the IPD turbo Cam, the A cam is going in and I'll be very interested to see if it increases the compression as-well-as reduces crankcase pressure.

The reduction in performance may be a compromise I'm willing to live with.