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Old 06-24-2020, 12:17 AM   #26
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What fuel injection or points and carbs?
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Old 06-24-2020, 02:20 AM   #27
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The plan is to use GSXR-1000 throttle bodies with some sort of cheap megasquirt knockoff. Just finished cutting the head and installing the valves. the head is finished and cc'd out at 41.

For calculating the compression ratio:


530 Head stock: 51.7cc
530 Head shaved: 41cc
gasket (1.2mm): 8cc
piston dome: 6cc
displacement: 579cc

Stock:
51.7+8+6=65.7

65.7+579=644.7

644.7/65.7=9.81

Shaved:
41+8+6=55

55+579=634

634/55=11.52

So it already gets quite close to that desired 12:1 compression ratio. I'll shave the block roughly 0.25 mm. That should result in a nice piston to head distance (<1mm) and bump the compression to roughly 11.9:1. Been thinking about something else. There is a general rule that for every 1000 rpm there should be at least 0.004'' (0.1mm) clearance to compensate for rod stretch. So if an engine would rev to 8K it'll have enough stretch to seriously increase compression. Is this compensated by the fact that after peak torque you wont get a 100% fill so it gets away with the higher compression or am i mistaken something here?

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Old 06-24-2020, 09:14 PM   #28
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I remember threads about the 'tight squish' where that kind of thing was discussed. If I recall correctly that had to be accounted for with a much higher than stock engine red line.
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Old 06-25-2020, 08:04 AM   #29
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Big edit:

As the piston rises toward TDC, the rod is actually under compression, so that's not a concern. Also, I'm not sure how much a steel rod actually stretches at these power levels, piston weights, and RPM. Somebody wanna do the math on this?

Last edited by shoestring; 06-25-2020 at 08:15 AM..
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Old 06-25-2020, 10:14 AM   #30
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My first Google can't up with this article on inertia, the 608g pistons in my build add up to 2986lbs on the exhaust up stroke at 6250 RPMs, I don't think I'll be running the engine past that after finding that little tidbit out.

https://www.google.com/amp/s/blog.k1...%3fhs_amp=true
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Old 06-25-2020, 12:30 PM   #31
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Quote:
Originally Posted by VB242 View Post
My first Google can't up with this article on inertia, the 608g pistons in my build add up to 2986lbs on the exhaust up stroke at 6250 RPMs, I don't think I'll be running the engine past that after finding that little tidbit out.

https://www.google.com/amp/s/blog.k1...%3fhs_amp=true
I'm here to burst your bubble and say that equation is grossly simplified.
I'll see if I can dig up the actual piston position vs crank angle equation... I have it somewhere...

It's up to you to find the acceleration, and then the forces from that
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Old 06-25-2020, 01:19 PM   #32
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Quote:
Originally Posted by culberro View Post
I'm here to burst your bubble and say that equation is grossly simplified.
I'll see if I can dig up the actual piston position vs crank angle equation... I have it somewhere...

It's up to you to find the acceleration, and then the forces from that
Exactly.
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Old 06-29-2020, 02:58 AM   #33
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Quote:
Originally Posted by shoestring View Post
Big edit:

As the piston rises toward TDC, the rod is actually under compression, so that's not a concern. Also, I'm not sure how much a steel rod actually stretches at these power levels, piston weights, and RPM. Somebody wanna do the math on this?

Thought a lot about my own noob question but here is what i think, During the compression stroke the cylinder is also filled with mixture that starts burning before tdc, So there is always pressure above the piston that keeps the rod from stretching. During the exhaust stoke there is nothing (pressure, force) left above there to keep it from stretching. Thus should be having no effect on the compression ratio.

I'll start to weight and match the pistons and rods soon. It'll be stock pistons with 13mm rods from a turdbo
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Old 11-03-2020, 04:14 PM   #34
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I am apparently very late to this party. What is the current state of this engine? Did you have the block shaved already? Did you first measure your piston to deck height? I'd much rather just use a thinner Cometic gasket than shave the block because I know for certain what the compressed thickness is and you retain full block strength(not really an issue I guess, hah).

13mm rods from a turbo are the same as 13mm rods from a non-turbo.

Did you hear back from KL Racing about intake valve openings or anything else that might make it's advertised numbers more relatable to something else? Robert, can you send one of yours to Shoestring for measuring, pretty please?

A 41cc chamber sounds pretty small to me but with a stock b230F bottom end and stock headgasket, if you have pistons that sit(sat) about .010"(roughly .254mm) above deck and took off .25mm, you around roughly 12.1:1 static compression with an assumed 6cc piston dish and stock headgasket. That leaves you with .027"/.686mm of piston to cylinder head clearance assuming the headgasket used is definitely .047"/1.194mm thickness compressed. That is a bit tighter than Erland Cox recommends on his motors(.031-.040"/0.8-1mm), but he revs them higher than 7000 and 8000rpm(sometimes 8500rpm). (Your dynamic compression calculation on the previous page shows you have an 86mm crank instead of the 80mm one?? - If so, that's actually 12.9:1 static compression with 41cc chambers, not the 12:1 you entered for your DCR calculation...)

On our current engine in the General Leif, one of the pistons seemed to be about .011" proud of the deck(while one of the others was somehow only .007") and we are using a .036" Cometic MLS gasket. It's somewhere around 11.3-11.7:1 with our 42/43cc chambers at the moment(3mm or so off a 405 head with very opened up chambers). So far it's rev'd to 7200rpm without an issue, but it's tighter clearance than we wanted.

Recently Erland suggested to me that the KL Racing S/T5 camshaft is ok for about 190hp where the ENEM C2 camshaft is good for at least another 20hp more. We're running what I think is a copy of a C2 camshaft at the moment. We haven't been back to the dyno yet, but it moves pretty damn well for what it is when coupled with the close ratio gearbox, 4.56 rear end and short tires.

https://youtu.be/0NkHMPvR4wY?t=760

He also recommended 3mm off the head, 13:1+ static compression and 16-17+ cranking compression(240-260psi!) with this C2 camshaft(I assume) and Europe’s 98 Ron octane(like 95 or so for us in the US). We have another B230 with squirters in the garage waiting for some time and money to slap some 97mm flat topped pistons in it. On that one I think we'll shoot for closer to 12.5:1 or so static with the same camshaft. Right now we are not detonation limited for maximum brake torque and are running around 4 degrees less ignition advance than stock at WOT, approximately(just under 30°). I have attached a picture of the head below for reference. Erland said " I take a little less towards the plug side of the exhaust and I don’t use Singh grooves." when I showed him a picture of our chamber.
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File Type: jpg A2B9C145-6B5E-416D-B03B-6DB01819018A.jpg (180.0 KB, 198 views)

Last edited by klr142; 11-18-2020 at 03:42 AM..
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Old 11-04-2020, 03:47 AM   #35
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Kyle, Good to hear from one of the NA guys!

I've actually bougt a set of forged rods and cleaned a bottom end and pistons that came from a good engine. Kind of ashamed to tell how the engine got together instead... Here we go. The car we bought had a b230FB in it, And that's also where the 531 came from. When we first removed a plug and took a look inside with the endoscope the cylinders looked a bit "dirty"but it was clear that it's a low mileage engine. Being that it has the squirters and thick rods we decided to pull the head and if usable just slap the head on there and give it a go. The dirty look was because someone decided to do some port matching on the intake side only but apparently forgot to clean the head after. There were quite a lot of debits left over in the bores so it's a good thing the po had never ran it this way. The bores cleaned up nice and it seems like a good place to start form to get moving under it's own power. so .. Stock bottom end, Like bone stock. The 530cc'd out at 41cc's i'm 100 percent sure of this. It has been milled quite a lot and has flat top oversized valves in it. I'll run the compression calculation again, Thanks for pointing me on that error. Unfortunately i didn't get any info out of KL, Guess i'll try it again tomorrow.

It doesn't look good for my 200hp target to be honest. Maybe i'll build another engine with the 531 the right way that was intended in the first place
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Old 11-04-2020, 07:34 AM   #36
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Is it possible that you put a two pieces of Fajs 50mm dual carbs to it.
Here in finland we have a good experiences about those china carbs.

in 200hp goal i wouldn't go any smaller than 50mm.
I know a person here, which runs a speed shop, he has made my head.
He had a cnc machine, dyno and a flowbench. He has measured that even 48mm carbs are restriction espesially if good intake are used (that kinda intake that does not restrict flow).

HE uses a sheetmetal intakes which is build by himself.

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Old 11-04-2020, 07:37 AM   #37
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HEre is a flow bench numbers at 530 head which he had build.
Not many people get those kind of numbers even with a 531 head.


235cfm at 530 head is very very good.
My head does not flow like this because it's ported to make a large register and good torque at 3500-7200rpm
My head flows something about 210-220cfm, i can't remember and i have flowbench raport somewhere that i can't found it.

But my point is that porting is very important in na-power and porting without a flowbench or a ton of experiences you could easily make your head flows less with so called "random-porting".

Also, combustion chamber shape is important. Here is a picture about my head's combustion chamber, which is made for forced induction.



Here is 220cfm intake channel:


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Old 11-04-2020, 01:51 PM   #38
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That's one awesome head! What kind of cam does he use in it and how much power does it make?
I just wish i put some more work in the exhaust ports.. Intake will be alright for this power level. If it doesn't make the power we wanted we'll pull the head again, Do some more to the exhaust ports, change to a thinner head gasket and swap in something slightly more radical of a cam

About the induction size i think you're wrong.. 50mm carb's usually have a 40 maybe 44 mm choke so i figure 46mm throttle blades without choke shouldn't be a restriction at all
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Old 11-04-2020, 02:33 PM   #39
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You are right, in 50mm webers they have about 40mm inner throat, but the butterflys are still 50mm.
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Old 11-04-2020, 02:36 PM   #40
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Quote:
Originally Posted by SkeTchy-MechAniC View Post
That's one awesome head! What kind of cam does he use in it and how much power does it make?
I just wish i put some more work in the exhaust ports.. Intake will be alright for this power level. If it doesn't make the power we wanted we'll pull the head again, Do some more to the exhaust ports, change to a thinner head gasket and swap in something slightly more radical of a cam

About the induction size i think you're wrong.. 50mm carb's usually have a 40 maybe 44 mm choke so i figure 46mm throttle blades without choke shouldn't be a restriction at all

He makes group-f rallycar engines, which usually uses camshafts about 280 *0.050, and something about 14-15mm lift, today he called me and tell that last motor he was built produces about 260hp and pulls to 8000rpm without significant power loss. (2,3liter b230)
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Old 11-04-2020, 09:28 PM   #41
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SO many topics that are all the same right now and I have so much to say that I can't type it all at once and I just lost my large reply. Damnit! Here goes again.

Quote:
Originally Posted by redblockpowered View Post
Seems like a lot of camshaft for 200 on the flywheel. How much compression? You'll need a lot.
We don't know what the 300° is measured at, so we have no idea what it is.

Quote:
Originally Posted by culberro View Post
You’re going to be short of your HP goal if using a stock intake manifold. That’s the real bottle neck on a 8v NA volvo.
Kyle (klr142) has built up and raced some very hot NA 8v engines for road racing (~170-180 crank hp), and you can find some of his stuff linked here:
[...]
He’s currently running some cam that’s a bit larger than the T5 cam, and it’ll be interesting to see how it does compared to the “small” cam he had in there previously.
At the point we did 157whp/160wtrq(STD correction), we were running an ENEM K13 cam and had a mildly ported 405 head at that point with somewhere around 2mm off on a near stock bottom end(.030" over and 16V flycuts) and stock headgasket. That is a good bit smaller than the S/T5 camshaft but I can't tell you how much. It's advertised as a "280°" cam with 12.5mm of lift. Our current cam is based off the ENEM C2 that is advertised as a "292°" cam and has 264° at .050" with peak lift of 13.9/14mm.

Quote:
Originally Posted by quillc View Post
I'm running a high compression B23 with an H cam and Stahl header connected to a 2 1/2" madrel exhaust. Feels about as fast as my stock 242 GLTi.
Stock flat top piston'd 1983/1984 long block or has it been apart for more compression and a thinner headgasket?

Quote:
Originally Posted by SkeTchy-MechAniC View Post
Kyle, Good to hear from one of the NA guys!

I've actually bougt a set of forged rods and cleaned a bottom end and pistons that came from a good engine. Kind of ashamed to tell how the engine got together instead... Here we go. The car we bought had a b230FB in it, And that's also where the 531 came from. When we first removed a plug and took a look inside with the endoscope the cylinders looked a bit "dirty"but it was clear that it's a low mileage engine. Being that it has the squirters and thick rods we decided to pull the head and if usable just slap the head on there and give it a go. The dirty look was because someone decided to do some port matching on the intake side only but apparently forgot to clean the head after. There were quite a lot of debits left over in the bores so it's a good thing the po had never ran it this way. The bores cleaned up nice and it seems like a good place to start form to get moving under it's own power. so .. Stock bottom end, Like bone stock. The 530cc'd out at 41cc's i'm 100 percent sure of this. It has been milled quite a lot and has flat top oversized valves in it. I'll run the compression calculation again, Thanks for pointing me on that error. Unfortunately i didn't get any info out of KL, Guess i'll try it again tomorrow.

It doesn't look good for my 200hp target to be honest. Maybe i'll build another engine with the 531 the right way that was intended in the first place
So, stock long block, stock headgasket, 530 with big valves and shaved for 41cc chambers? Run it and let's see how it does!

I'm also glad to hear your motorcycle throttle bodies are as large as they are. I was worried they'd be too small and you'd have this problem: ITBs that basically make the same power as a B230F intake manifold?! 2.5mm shaved off a 531 head with port work and stock valves, Timos 13.10 camshaft, stock bottom end.

Quote:
Originally Posted by Jussi Alanko View Post
He makes group-f rallycar engines, which usually uses camshafts about 280 *0.050, and something about 14-15mm lift, today he called me and tell that last motor he was built produces about 260hp and pulls to 8000rpm without significant power loss. (2,3liter b230)
280° at .050" is quite wild, for sure. Like 240hp+ engines just as you say with 15mm lift or more. Do you have a cam spec sheet to show what you have for your engine, Jussi? You say your TURBO head has a 280° at .050" cam as well and only 12mm of lift? That's pretty odd, if so. Your head flow(unless it was another head) sheet you posted somewhere shows you can use more lift than that so I'm surprised it's so low and still with the large downside of so much duration.

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Old 11-04-2020, 09:58 PM   #42
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Quote:
Originally Posted by klr142 View Post
SO many topics that are all the same right now and I have so much to say that I can't type it all at once and I just lost my large reply. Damnit! Here goes again.

We don't know what the 300° is measured at, so we have no idea what it is.

At the point we did 157whp/160wtrq(STD correction), we were running an ENEM K13 cam and had a mildly ported 405 head at that point with somewhere around 2mm off on a near stock bottom end(.030" over and 16V flycuts) and stock headgasket. That is a good bit smaller than the S/T5 camshaft but I can't tell you how much. It's advertised as a "280°" cam with 12.5mm of lift. Our current cam is based off the ENEM C2 that is advertised as a "292°" cam and has 264° at .050" with peak lift of 13.9/14mm.

Stock flat top piston'd 1983/1984 long block or has it been apart for more compression and a thinner headgasket?

So, stock long block, stock headgasket, 530 with big valves and shaved for 41cc chambers? Run it and let's see how it does!

I'm also glad to hear your motorcycle throttle bodies are as large as they are. I was worried they'd be too small and you'd have this problem: ITBs that basically make the same power as a B230F intake manifold?! Shaved 531 head with port work and stock valves, Timos 13.10 camshaft, stock bottom end.

280° at .050" is quite wild, for sure. Like 240hp+ engines just as you say with 15mm lift or more. Do you have a cam spec sheet to show what you have for your engine, Jussi? You say your TURBO head has a 280° at .050" cam as well and only 12mm of lift? That's pretty odd, if so. Your head flow(unless it was another head) sheet you posted somewhere shows you can use more lift than that so I'm surprised it's so low and still with the large downside of so much duration.
Yes i have different head.
And now i realize, my cam has 280 degrees at 1mm lift, not at 0.050, so there will be difference, my head is ported to a street use so it had good flow numbers at lower lifts also. And channel sizes are keeped relatively small so it has a broad torque curve (i'm little confused because in Finland we talk mainly at 1mm lift when we talk about camshaft durations).

Damn, i had to find that flowbench raport!
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Old 11-05-2020, 01:30 AM   #43
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Quote:
Originally Posted by Jussi Alanko View Post
Yes i have different head.
And now i realize, my cam has 280 degrees at 1mm lift, not at 0.050, so there will be difference, my head is ported to a street use so it had good flow numbers at lower lifts also. And channel sizes are keeped relatively small so it has a broad torque curve (i'm little confused because in Finland we talk mainly at 1mm lift when we talk about camshaft durations).

Damn, i had to find that flowbench raport!
It's all good! Even still, 280 degrees at 1mm is SERIOUS duration and a lot for a street car. Usually that much duration is used with camshafts over 14mm of lift: AGAP's B230 camshafts. Our camshaft in the General Leif and the ENEM C2 is like their R33-264-14.0 which has 270 degrees at 1mm and 264 at .050" and that's good enough for 220hp or so depending on the rest of the setup. I'm really curious what we have with our less than optimal intake elbow setup and ported but STOCK exhaust manifold!

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Old 11-05-2020, 02:18 AM   #44
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It's all good! Even still, 280 degrees at 1mm is SERIOUS duration and a lot for a street car. Usually that much duration is used with camshafts over 14mm of lift: AGAP's B230 camshafts. Our camshaft in the General Leif and the ENEM C2 is like their R33-264-14.0 which has 270 degrees at 1mm and 264 at .050" and that's good enough for 220hp or so depending on the rest of the setup. I'm really curious what we have with our less than optimal intake elbow setup and ported but STOCK exhaust manifold!
Volvos exhaust manifold is not that bad at all, i don't think it is a massive restriction. Just built little bigger secundaries and put a good collector, then you have a decent exhaust system.
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Old 11-05-2020, 02:32 AM   #45
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Quote:
Originally Posted by Jussi Alanko View Post
Volvos exhaust manifold is not that bad at all, i don't think it is a massive restriction. Just built little bigger secundaries and put a good collector, then you have a decent exhaust system.
Agreed! I was surprised that it's doing as well as it is on our car with only 44.5mm secondaries when 51mm are recommended for this camshaft and power goal.
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Old 11-05-2020, 06:33 AM   #46
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Stock flat top piston'd 1983/1984 long block or has it been apart for more compression and a thinner headgasket?
Stock flat top pistons in an 83 block. Head has been shaved with a thinner HG. Static compression is ~10.8:1 or so.
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Old 11-05-2020, 02:25 PM   #47
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Nice. Probably pretty similar to my 244 at the moment then.
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Old 11-06-2020, 12:01 PM   #48
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Hmm is it better to have the chamber shaped for air flow or smaller for higher compression? Trade offs I know.
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Old 11-06-2020, 03:19 PM   #49
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The combustion chamber? You can't use a reasonable camshaft without compression. Without compression, you can't make torque and have a reasonable powerband with a reasonable camshaft.

Trade-offs, sure, but a shaved, stock cylinder head with a reasonable camshaft(11-12.5mm lift and more duration than stock, such as a K, ENEM V15, V16, KY112, KY122, FS1041, Timos 12.2 or similar), will make very reasonable power. Like 125-145whp depending on the setup and tuning.

If you don't shave the cylinder head and do some unshrouding of the valves, you're going to lose compression depending on how far you go. You can regain some or all of that lost with a thinner headgasket, assuming you have piston-head clearance to do so. Swap in a similar camshaft to the engine above and I expect you'll have less torque(and thus HP) everywhere except maybe at high rpm, and a less driveable car(by a small margin, the smaller the camshaft, but by a large margin if you're using a camshaft that has a large bump in duration compared to stock as your dynamic compression will be lowered so much). Eliminating-cylinder-head-valve-shrouding-improved-performance-part-9

For best results, DO BOTH because you have the head off anyway, but I don't think you're missing out on that much at this mild of a build(as stated in this post, with stock valves, etc..). Any gap between the valve edge and the chamber that is less than the amount of valve lift at that point will be a flow restriction of some sort(roughly - see link above). How much it is a restriction, and what is going to be better than something else is going to be impossible to determine without a flow bench, and even then it's going to be hard to determine. Don't open it up a ton unless you are prepared to take 2mm or more off the head.

I have attached some photos below for some reference material. I'm not certain if the 405 chamber in the first photo(or imprinted on the piston) was stock or already opened up a bit, but you can see in the piston imprint that some of the piston's dish goes outside of the chamber in the head. Ideally, all of the dish in the piston would open up into the chamber and not have any overhang, at least according to one European I spoke to when making my chamber modifications. He also said that he likes to get the spark plug a little more into the chamber by removing some material around there. I did some work after the picture with the red outline, and Robert(culberro) made it even better the next time the head was off with some unshrouding of the intake side which I mostly left alone. This 405 head has around 3mm removed so I was trying to lower the static compression, anyway. Right now we are around 11.5-11.7:1 with a .036" Cometic gasket and around 010" of piston poke on a .030" over b230F with 42-43cc chambers. Ideally, we would not have opened up the chambers that much because for the camshaft we're using, we really want over 12:1 compression, close to even 13:1 compression. Erland said these chambers look ok but "I take a little less towards the plug side of the exhaust and I don’t use Singh grooves.". Do with that information what you will. You can also look at his webpage: https://www.topplocksverkstan.se/volvo8v531.html
Attached Images
File Type: jpg Piston with chamber impression from the head.jpg (171.0 KB, 100 views)
File Type: jpg 2019 405 head's chambers before modifying.jpg (47.0 KB, 96 views)
File Type: jpg 2020 405 head's chamber.jpg (198.3 KB, 100 views)

Last edited by klr142; 11-19-2020 at 02:11 PM..
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Old 11-06-2020, 03:46 PM   #50
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Originally Posted by 122power View Post
Hmm is it better to have the chamber shaped for air flow or smaller for higher compression? Trade offs I know.
Airflow over compression every time, within reason. The man that literally wrote the book says so.
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