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building an NA that could

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.

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.

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.

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?

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:lol:. 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.

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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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!
 
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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:) 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.
 
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.
:nod: 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.
 
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.
 
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
 

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A Singh groove. It is supposed to help evacuate the quench pad and create more turbulence thus providing a more complete burn, better efficiency and better knock resistance. Results may vary and our next head will not have them.
 
No complaints specifically, I just don't think it's necessary and can't say for certain that they're worth the effort. Another person in Europe swears he had a good result with them, but I'm curious how his engine would've done without them in the same scenario. It also can create hot spots in the combustion chamber if not smoothed well enough, it might be a weak spot for cracking at some point(haven't heard of a problem on these heads, though) and/or might even fill up with carbon over time(haven't experienced this yet, but we're a race car at full throttle most of the time).

Search Singh groove on here and you'll find other threads, including a recent one.
 
No complaints specifically, I just don't think it's necessary and can't say for certain that they're worth the effort. Another person in Europe swears he had a good result with them, but I'm curious how his engine would've done without them in the same scenario. It also can create hot spots in the combustion chamber if not smoothed well enough, it might be a weak spot for cracking at some point(haven't heard of a problem on these heads, though) and/or might even fill up with carbon over time(haven't experienced this yet, but we're a race car at full throttle most of the time).

Search Singh groove on here and you'll find other threads, including a recent one.

I kinda had the same question but forgot to ask it! I really think those a such marginal gains that it ain't always worth it on every engine, Like cutting a small piece of the spark plug and bending the edge so the spark is more pointed towards the combustion chambers.. There are stories of it making a noticeable difference on an all out racing motorcycle, But never noticed a difference myself.:lol:

Just finished an order at KG, I've got to be honest.. Every time i visit their site there is an attraction to the cam section, And especially the KG8 and KG9. Maybe another time after we've been disappointed with the power output of the KL T5. Finished the order with an underdrive crank pulley and new crank gear with shims. Never knew it was possible but the PO proved you could **** up a simple timing belt swap on a b230:roll: We fitted the cam and set lash to the correct spec. when turning the engine we noticed the belt walking off the cam the cam gear but didn't think much off it because the stock tensioner was fully adjusted outward. With the lash set and the adjustable timing gear installed we started what we thought was the final assembly with a modified tensioner. Everything bolted up with proper tension on the belt but it still tries to walk off. Cam gear and tensioner came from one of my older engines and never given any problems... Suggestions ?
 
Just finished an order at KG, I've got to be honest.. Every time i visit their site there is an attraction to the cam section, And especially the KG8 and KG9. Maybe another time after we've been disappointed with the power output of the KL T5.
I think you would get a better powerband from going with more lift and less duration. Assuming your head flows better at high lift, anyway. It's also impossible to say what lift their advertised durations are measured at without asking them and getting an answer. Shoestring tried a KG7(I think?) and it wasn't good in his engine, but it wasn't tuned for it, either. He did get it with a 110LSA which probably was killing his mid-range torque more than expected, too. It likely idled better than it would've with a 105LSA or so that would've improved the grunt out of corners if they ever got that far with it.
 
FYI Side gap spark plugs do improve the spark in the chamber. They have been used as the stock type of spark plug in Mercedes and Porsches since the 60s. I've used a platinum version W6DPO and WR6DPO is stock for some Mercedes and the VW G60 engines. They were the most expensive plugs I've ever bought but worked great and lasted a long time. But I admit they were more of an experiment to see if they worked well.
 
I think you would get a better powerband from going with more lift and less duration. Assuming your head flows better at high lift, anyway. It's also impossible to say what lift their advertised durations are measured at without asking them and getting an answer. Shoestring tried a KG7(I think?) and it wasn't good in his engine, but it wasn't tuned for it, either. He did get it with a 110LSA which probably was killing his mid-range torque more than expected, too. It likely idled better than it would've with a 105LSA or so that would've improved the grunt out of corners if they ever got that far with it.

Yup, KG7. Car didn't like it and it was worth effectively nothing over the K cam, peak power and RPM included.
 
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