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531/405 vs 530 heads with camshafts under 12.5mm

I don't think anyone meant to say port flow numbers are worthless. My intent at least was to point out that they represent a single variable in the system and need to be considered in context.

Peak power and peak torque are typically each made within a reasonably narrow band of port velocities. Especially since we are dealing with a "wet" port...

You can't just say "oh add duration to compensate for a lack of high lift flow", etc. It's myopic.
 
The exhaust is still flowing more at 14mm of lift, but yeah, who knows WTF is going on with the intake side on my head. You bet I was curious when I got that print-out.

EDIT: It's a bogus head job and bogus flow chart.
 
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I don't think anyone meant to say port flow numbers are worthless. My intent at least was to point out that they represent a single variable in the system and need to be considered in context.

Peak power and peak torque are typically each made within a reasonably narrow band of port velocities. Especially since we are dealing with a "wet" port...

You can't just say "oh add duration to compensate for a lack of high lift flow", etc. It's myopic.

While they represent only one aspect of the head they are one of the most valuable figures available when selecting camshafts, intakes and exhausts.

I personally DGAS about peak HP, it's about the curve. Dyno queen peak HP numbers don't mean jack **** unless it can be used properly.

As for the duration comment, well when you have the head installed on the car and it's not getting further porting or bigger valves, then what do you do? Keep in mind that his car is NA so you can't just force more air in the engine. More duration can increase the fill, allowing higher volume into the chamber, increasing HP. While my cam experience specifically to Volvo engines is limited I have much experience on domestic V-8 engines, having selected several custom cam grinds for various engines I have built. It works the same, you might just have to trust me on that one.

Your intent and the way you come off in this thread may be entirely different, you came off like a dick. I don't really think you are like that, or at least I would hope not, but you have to keep in mind that there are many others on this forum with the skills to understand this data and what to do with it. When you add in the OP's statements with zero supporting data it's just an opinion. No facts = opinion.
The exhaust is still flowing more at 14mm of lift, but yeah, who knows WTF is going on with the intake side on my head. You bet I was curious when I got that print-out.
Yep, the exhaust side looks great, but in my experience the real problem on our heads is the intake. Maybe there's an error on the sheet or the bench took a nap, it's way better than stock but totally flat well below the cut off where it has been stated the 531 would be superior.
 
stock 531 head , intake to a little over 15mm and exhaust to a little under 13mm
72000325.jpg


ported 531 from erland cox's website
http://translate.google.com/transla...n.se/volvo8v531.html&sl=sv&tl=en&hl=&ie=UTF-8

i have some more flow numbers i need to scan and graph.
 
you came off like a dick.

Just so you know, you sound like one in almost all of your posts as well and are the main(only?) person who is calling people names repeatedly throughout the forum without knowing who they are... Kenny isn't too much of a dick in real life, at least not from the short time I've been with him. The real thing is, who wouldn't come off as a dick in this forum, there's too much bull**** to not slap people around some.

When you add in the OP's statements with zero supporting data it's just an opinion. No facts = opinion.

Jonathan is and always was intending to post facts. He had a good thought to start a GOOD thread(which is not seen on this site anymore, because too many asshats will post up and f**k with things and just piss everyone off) and get the juices flowing. It doesn't matter. If you're patient, s**t will come to you. Shut up and wait if you're so concerned about the flow numbers, we don't need to hear you filling up the internet with saying the same thing over and over.

Yep, the exhaust side looks great, but in my experience the real problem on our heads is the intake. Maybe there's an error on the sheet or the bench took a nap, it's way better than stock but totally flat well below the cut off where it has been stated the 531 would be superior.
Flat is better than falling off, but what is there to believe when the last two numbers are the exact same...? That being said, the head is not the restriction on my car. I think the car would perform almost the same, if not better in some aspects, with a standard head and mild port/valve job. :e-shrug:
 
This is a comparison chart showing my old Sten Parner head (RIP), my current Erland Cox/Pacman head, an early RSI stage 2 head (not sure what changes have been made since) and a stock 530 head. All of these were flowed on the same bench...
 

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These are flow numbers from my current race head. The first flow chart was done by Erland Cox, the second by Larry Widmer at Endyne - same exact head, no changes made between the two different flow charts.

So, with differences between flow benches, how can flow numbers even be discussed as a comparison on a forum?

Furthermore EVERY engine package responds differently to flow at various valve openings and valve sizes, and velocities and on and on and on. These are the tools we use to maker our best guess how an engine package will perform in real life. Then you go back and start all over because the result is not what you expected/wanted. It's all fine to discuss "theory" but if anyone tells me that they think they can look at flow data and make solid conclusions I say yeah, right.
 

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Not saying Kenny IS a dick, just that he comes off as one in this thread. Yes, we are inhabited by quite a few who know nothing but preach as if they know it all, but when someone requests information that would validate the OP's claim then why argue? I have legitimate questions on this subject as I don't want to be continually building heads or swapping cams to get what I want out of my engine.

I know that Jonathan has intended to post real data, that's what I am looking for, not someone going off on tangents that are out of the realm of a reasonable engine build.

When someone asks for information that is common in the world of engine building and the response is something between you don't need that and you don't know what to do with that it is just reinforcing why so many people have not built Volvos. Posting the data would allow others to select the correct components for their needs the first time rather than constantly changing components.

It would also sell RSI's heads and cams..........

As for patience, I can wait for the information, but there's no reason for anyone to come at me as if I don't know what I am doing.
 
Understood. :)
there's no reason for anyone to come at me as if I don't know what I am doing.
Don't take it personally, some of it may be directed at you but some of it may be directed at the general public who aren't smart enough to fully understand(none of us truly are, but you know what I mean) what is being discussed. Remember, we have to try and keep it at least somewhat PG for the less educated to help understand.

I really need to be doing other stuff, but I'll get back to your PM in a bit. Thanks for sending it. :)
 
Understood. :)Don't take it personally, some of it may be directed at you but some of it may be directed at the general public who aren't smart enough to fully understand(none of us truly are, but you know what I mean) what is being discussed. Remember, we have to try and keep it at least somewhat PG for the less educated to help understand.

I really need to be doing other stuff, but I'll get back to your PM in a bit. Thanks for sending it. :)

I know what you are getting at and don't take it personally. I'm just frustrated with the resistance to sharing information on here. Yes, some will interpret it wrong, I have in the past as have all of us at some point, but it's for the greater good of the community. When the posts are directed at my posts then I do take it as directed towards me.

I disagree in keeping it PG, we need to have all the information possible, then those who know how to use it can help others by teaching them or guiding them to the right choices. While too much information is just as bad as too little, I don't see the reason to not share what we have here.

Do OTHER stuff? Yeah, I'm about 50% done with an instructional I am writing right now, just come back to TB to clear the head and wait for approval of revisions.



Have you kicked Pat in the shin for me yet? Where has he been?
 
I disagree in keeping it PG, we need to have all the information possible, then those who know how to use it can help others by teaching them or guiding them to the right choices. While too much information is just as bad as too little, I don't see the reason to not share what we have here.
[...]
Have you kicked Pat in the shin for me yet? Where has he been?
That's what I meant, not that we have to keep all info PG, just add more info in as needed and make sure everyone knows that not everything said is always a straightforward fact with nothing else being important or necessary to know/discuss.

Haven't kicked him yet, he was already down. Actually, I've only seen him once for a couple seconds since I've been back...
 
Just for grins, this is the cam data for the ENEM C2 I am currently using.
 

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I'm here to learn, always have been. It can be hard sorting fact from theory though. Often theorys get presented as fact. That's true almost universally I think. Most people in performance have useful information to contribute, but the one thing lacking is factual data. There's often no before/after results for many of our mods, just hearsay. So, I lump all the information I can get together and make a go at it based on that. This time around, it means i'm trying a mildly ported/matched 531, RSI stage 1 cam and a stock b230ft. Maybe the 531 is overkill, maybe it isn't. I'll let my MPG and overall street performance dictate if i'm happy with the 531 or not.

Keep crankin the info guys, I find it fascinating.
 
I've been staying tuned to this as well. Seeing how much a 530 can be cleaned up vs. the size and design differences of the 531, it's been quite interesting. My 531 is currently at the MS anyway for a crack repair, but it'll see some blending on the exhaust side and that's about it before it goes back on the motor.

Interesting, the RSI cam's don't even get big enough to need a 531 until you're talking non-streetable per their spec, yet the 531 was a stock spec head for overseas. What's missing here?
 
Interesting, the RSI cam's don't even get big enough to need a 531 until you're talking non-streetable per their spec, yet the 531 was a stock spec head for overseas. What's missing here?

The 531 head was only fitted to the 740 and as far as I'm aware it was always used with an A cam, the A has 10.5mm of lift and 254 duration. The 530 was used on the later cars with a T cam, 9.94mm of lift and 225 duration.
 
The 531 head was only fitted to the 740 and as far as I'm aware it was always used with an A cam, the A has 10.5mm of lift and 254 duration. The 530 was used on the later cars with a T cam, 9.94mm of lift and 225 duration.

Volvo 940 could be had with a B230FB engine too. A B230F had a 1000530 cylinder head and a M-cam, and i think 115 hp. The B230FB had a 1000531 head and a VX-cam (or maybe VX3, can't remeber for sure which one) and 136 hp.
 
Interesting, the RSI cam's don't even get big enough to need a 531 until you're talking non-streetable per their spec, yet the 531 was a stock spec head for overseas. What's missing here?

This is what I was trying to explain before everyone got butthurt and started calling me names.

The point is that a ported 530 will not give up the area under the curve that a 531 will.
Stock for stock the 531 makes a little more power. Nobody's arguing that.

But, if you want to build something that is say, sub 400whp (Jon could comment better on what the actual output might be, I'm just guessing), and doesn't necessitate a gnarly cam, a worked 530 will not be a restriction, and will provide better midrange torque than a 531 will. All you are doing going with a 531 is costing yourself midrange. The 531 is only truly a better choice on a wild enough build where the power band and cam choice reflect the stage at which a worked 531 will have ideal port velocities, etc.
 
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