Modified cylinder head

Hi folks,
For a little while now I've had a thread going on ClubVolvo that has the results of flow testing
and porting a 405 BCP head. On the second page I've added photos of the test chart
and pictures of the head. These are before and after tests to show the tangible results. He told me he could go much further with the intake but this was for street performance and
it was important to keep a level of balance between intake and exhaust.
Enjoy!

http://www.clubvolvo.com/forums/showthread.php?s=&threadid=1910&perpage=15&pagenumber=2

so he port-matched the exhaust ports eh? what few things ive read have said to leave a head-side port smaller than the manifold-side port to improve scavenge... you guys are obviously experts, is the lack of turbulence a better benefit? the head looks awesome

I left it up to him.

the poi said:

so he port-matched the exhaust ports eh? what few things ive read have said to leave a head-side port smaller than the manifold-side port to improve scavenge... you guys are obviously experts, is the lack of turbulence a better benefit? the head looks awesome

Click to expand...

Thank you. On the receipt it says match gaskets. It may be both intake and exhaust. I'm no
expert so I wanted to leave it to someone who was. This shop has been around for a long
time and the guy that did this work modified the head for a 10sec VW Golf. He has worked
on Volvo heads before. So he is very familiar with port design on sohc 8V motors. I'm very
happy with the increases and look forward to trying it out.
Best regards,

ive seen flow figures for a modified 530 head with bigger valves 46/38 , that flows about 120 cfm @10 inches at .500 lift , so it would appear you are in the ballpark somewhere . Just think about adding bigger valves to get that same percentage increase again ? frommy expereince in a N/A motor that would be at least 10-15 hp at the flywheel , good work .

oh , just ran those flow figures through dyno sim , equates to about 210 hp - 280ilbs/ft torque - with a V15 turbo cam , oh and 10 psi , a very nice broad torque curve aswell . of course thats just a simulation so take no real substance from it .

Nice looking head Dave....

Where'd you get that puppy from??

Oh yeah...I remember now...Nevermind

nice work dave! could this possibly pull you from the 17 second bracket? When are we goin to englishtown again? take care
=pete

Hi all!

Havent been here at this Forum before, and is not planning to stay either
I can make a short presentation of myself: I am a engine-tuner in the south of Sweden and Volvo Engines is my specialty.

I must say that its very fun to read and know that there are more Volvo enthusiasts out there in the big world =)

Now to the issue!
I have watched those pics of dlot's 405-head and i must say that the tuner that did that work cant have done much wear of the grindingtools =P
I grind MUCH harder in the turn, and make the D-turn more like a O-turn.
The same to the fin....i make it look more like a shark-fin....that is I grind it much deeper!

The result?!.....well.....my smallest "fast road"-tuneup of a stock 405 w stock valves flows about 131 CFM @ 10" dp and the more racetuned 46mm/38mm stainless valves flows 149 CFM @ 10" dp.
To go 48mm/40mm one would have to shift the seats to bigger ones, and those heads flow 155 CFM @ 10" dp
All flows is measured at 12mm lift, which is about 0,472"....because here at Volvoland (Sweden that is...hehe) the K-cam (11,95mm) and H-cam (12,00/11,90) is the most used in cheap fast turbos.

I would love to port all your heads if that would be possible, but i dont think you want to send your heads all across the world just to tweak that old Volvo up a bit
To give you turbofreaks something to go for, I have my self won a few streetraces against those japcraps here.....Old Volvos dont die....they just go faster!!
-Two scalps: One lightly tuned Honda Civic TypeR -02.....and one Subaru Impreza WRX.....both left behind in just over 1/8 mile (~250m)
-Acceleration: 0-60mph in less than 5sec.....0-120mph in about 16-17sec

This is just my slightly modified streetlegal 244 '85.......
There are many 10sec 240s around here in Sweden w 2,5 litre-cranks, 16valve-heads and huge turbos......the key to get it all to work seems to be aftermarket EMS like Motec, Haltech or Autronic. There is a growing number of MegaSquirt-managed engines aswell....

Just to set you guys on fire again =)

Be well// Pacman

Nice work Dave!

Pacman, got any pics of the headwork?

My server is down at the moment.....but as soon as it is back online, i'll put the pics out!

Pacman, maybe you could sell some worked heads to us. Instead of us shipping ours over. Have access to some 531 heads? Or some other nice ones? Heck your the expert, can you get the other heads to flow almost as well? Wonder what a good price would be. Guess heads are pretty heavy, haha.

Pacman suggestions

FYI, I wanted this head done conservatively so I have a good baseline to start with. This head isn't for a motor that is going to be a member of the 300hp club. It's a good start toward that. I also have to pass emissions easy so I won't be using a cam like a H or K. This will have an enem V15 turbo model cam installed.

Pacman, please post some pics and better information about what you mean. What part of the port? What is the D turn, O turn and shark fin part? I appreciate any suggestions
for an even better done head next time. Always better to start conservative, with experience
and more information my shop will do even better work.

Thanks for your comments everyone!

Okey....my bad!
I guess I got carried away by the hp-inflation =)
Back here 300hp is nowadays the baseline for a medium streetracing car.....even in old Volvos.

The before mensioned 10sec ones are well above 5-600hp and some few maniacs are touching the magic kilo....1000hp in a old Volvo fourbanger means respect!

Of course I could get hold of a couple of 531-heads, port 'n' polish them and then send them abroad for sale. It's just a matter of some practical issues like payment, shipment and stuff like that.

I'll be back with more info as soon as I have thought this over (and spoken to my master aswell of course).
The pricetags may differ since the Dollar/SEK rating is never stable =/
I'll make some mathematic gymnastics with that too....

How big is the demand of tuned Volvoheads anyway?
405/531 SOCH (B21/23/230) ?
16v-heads (B234) ?
B5234 (850/x70) 20v-heads ?
B6304 (960/x90) 24v-heads ?

-

I think this board could definately use some Swedish contacts. Probably only a handful of people might want heads now, but I would think demand for things would continue in the future. Considering the 531 is very rare in the US, hrm. I'm sure you have access to a lot of things we don't over here.

how much is it to have a head flowed? I recently had a 531 head seriously worked over by HBR and would like to see how much its flowing now.

Thanks for posting the info and pics, d.
I know what you mean about conservative. I ruined the first head I ported, and I keep it around for show+tell. Most people who have been to school where I work have seen it.

Prices 'n' stuff

Hi again!

Have calculated a bit now, and have come up with these figures.
Before I must say that these specific head configurations mensioned is just those most popular right now. We normally customize every head to the costumers very own choise, and when the costumer dont quite know what to choose, we simply ask which camshaft is going to be used and how high the engine is going to rev.
Then the amount of money to spend is a highly prioritized matter as well of course =)
The foreign prices (all but SEK) is calculated with todays change value. It will of course differ!

1: Road/street 44/35.....Stock valves, stock springs, stock head.....just port, polish, 3-angle radius seats, 2-angle valvejob (ie "backcut"), and a slight shimming (right eng word??)
Price incl. used 531-head (excl. camshaft): 6000 SEK, $770, ?650

2: Light Race/ Street 46/38.....No1 + new Stainless Steel valves, new hardener springs (up to 8000 rpm)
Price incl. used 531-head (excl. camshaft): 8500 SEK, $1090, ?920

3: Light Race/ Street w increased exhaust flow 46/40....No2 + new exhaust seats
Price incl. used 531-head (excl. camshaft): 10500 SEK, $1350, ?1140

4: Full Race 48/40....No2 + new seats all over (260+ hp n/a w race camshaft)
Price incl. used 531-head (excl. camshaft): 12500 SEK, $1600, ?1350


The standard question is: -"how many hp will i get with that head?" and of course it is almost impossible to answer. It depends so much on the rest of the engine setup and not at least the later on tune in a bench or on a local highway.
The most important gadget in the engine is the camshaft!!
If one wondered how important the camshaft is for the allout performance, one would never even question the tiny pricetag a performance camshaft has.....

Just to mension some figures, there is a guy in Finland named Sundsten who has benched his 2,6 litre B23-engine to 850hp@3,6 bar absolute with a 531-head almost identical to our No3.
Ours just flow a few CFM better

<img src=http://www3.telus.net/public/iadr/b23_Ian_heartchambers2a.jpg </img>

and I'm still fooling around a bit. Those are 46/38mm valves, and I probably should upload a pic of 46/38's in a stock 398 chamber so the difference really shows. Chamber is now about 60cc, un-milled.


edit:
<img src=http://www3.telus.net/public/iadr/b23_chamber3a.jpg </img>

Welding

That upwelded comb.chamber shaped as a heart highly improve the flow in and out, if the walls are ported right.....as "diffusers" to the valves and seats.

We have tested that on a Special Custom 50/40 high-rev 531-head specialmade for a close friend of my master who runs a Mercedes 190 DTM Evo-3 w a Volvo n/a B230 2,6 litre, cranking about 290 hp.
The goal with these comb.chambers together w the 50mm intake valves (and a 4mm strafe of the head to the intake benefit) was to get well above the 300hp-limit....(the goal was actually 330hp) but we learned a great deal about the limits of exhaust flow here!!
The intake flowed well for 340hp.....but not the exhaust!!

However.....how good that welding ever does to the flow, nobody is prepared to pay the money we want for the job!
The head twist and bend as a bad banana when the TIG is turned off, so before shimming, the head must be set under pressure and straightened out. Otherwise the camshaft dont fit as it should. With bad luck and a big measure of Mr Murphy, linehoning is still a must!