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low power output? b230a rally motor

i had asked Timos ages ago for the price of a camshaft, and it hink he gave it me but when i asked to order it he never replied, and i mailed a few times.

But he said they run at least 12,2mm lift 286 dur, in the 213hk engines lift is about 13mm and over 300 dur.



so what should i do to my engine then? if i have a go at the exhaust ports, and skim the head so i get 12:1 static? will that make 180 bhp with the cast manifold? I could make my own exhaust manifold but id rather loose 5bhp than spend the time making one as this engine is in a RHD bmw compact.

I do actually own the bigger valves that fit in the head, i forget their sizes, maybe i could get a 530 head and port that and put these valves into it. keep the 531 as it is.

i dont know what to do but i had a m44 bmw engine in the car before, it made 180 bhp and 160 lbs, now i was told the 2.3 would be a lot more torque and 190 bhp by everyone i talked to, but so far its far from that.

thanks!
 
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fix up a 530 head and sell the 531 when your ready to do the swap. Step down on cam a little. Get a good intake and ex. manifold. At least thats what I would do.
 
You need to extrude hone the intake manifold, or use a k-jet manifold and extrude hone it, it flows a little better and have a bigger plenum.
Your compression must be between 12:1 to 13:1.

HEad is moast important thing, you need to change valves to 46/38, then port the 530 head. (my ported 530 with 46/38 had flow rates to make 220hp).

Then you need good headers to it.

Your camshaft is good enough.

If needed more power port the 531 with bigger valves and install a cam that has max lift about 14.5mm and duration at 0.050" something about 280 degrees.
 
You need to extrude hone the intake manifold, or use a k-jet manifold and extrude hone it, it flows a little better and have a bigger plenum.
Your compression must be between 12:1 to 13:1.

Jussi, the power figures you mentioned above with the Timo’s cam, was that with an extrude honed or ported intake?
I ask because the ID and CSA of a b230f intake runner is VERY small, especially at the fuel injector area.

I fully agree on the compression numbers. People are afraid of high compression for some reason. I don’t understand.
 
id like to fit the k-jet, but i thought the lh2.4 was better, but now i know it isnt. the car is set up for the lh2.4, and i dont have the holes in the head for the injectors.

I forgot to say, i do also have a 530 head, that is mildly ported, it had standard chambers, and a light skim but it had 46/38 valves put into it. When trying to get the car running, i had an oil pressure problem and the cam partially seized on the carrier, and its quite scored. Also the guy who fitted the valves sunk them into the head a bit as the shims for the buckets i supplied where only 4mm so not long enough.

So i could either sort the cam out on that 530, and the chambers etc. Or port the 531, or port the 531 and fit the bigger valves. But i recon with the cast exhaust manifold also will restrict it. The inlet "im not alowed" to modify at all. Interesting about the extrusion honing, is that expencive? be good maybe for the exhaust manifold!

thankyou very much for all the replies. Ill keep the t5 camshaft, but not sure which way to go just yet,.
 
This is for road rally correct? Not performance stage rally?

For what you want, skimming the 531 to get 12:1+ cr seems like the best place to start. If you can have the exhaust ported at the same time, even better.
 
yes, but when i say road rally, its basically a stage rally car with a few bits removed. It has 3 way suspension, big plated diff, 996 porsche 4 pots and motorsport abs, etc etc. Will that get me 190 bhp at the flywheel?

i can port the exhaust manifold, i can replace it but the space of the bmw to vovlo engine and right hand drive is tight. the cast fits so well.
 
ive never seen th is extrude honing before, is it expencive?

Yes, it is expensive. It's kind of like having stuff like brake rotors cryogenically treated. It's a somewhat expensive process that works well and you are glad you got it done. But you have to pay the cost to get there. Extrude honing is a process where an abrasive is forced through the interior of something like an intake manifold. It is great for smoothing the interior of a manifold so the airflow is improved and total airflow is increased. The Porsche crowd likes to have the intake manifold done on the 80s Motronic 911 engines for improved performance.
 
You need more compression to get the cam working. I thought you were having a head porting and using the bigger valves?

On the throttle body you can machine it out and use the K jet throttle plate
 
its a bit of a story, i had the original engine rebuilt by someone who i thought knew what he was doing. So i ended up with the 530 head, big valves, ported, but no skim to the head, and standard chambers. It was about 11:1 static. Also the shims i bought where the 4mm ones, they where too short, so he had the valves recessed into the head by about 1mm! I had paid the guy ?1700 to build it!

Not having any clue about what had happened, i took the car to get tuned, and it made 141 bhp! So i put the bigger exhaust down pipes on it, and had the head skimmed.

then it was like 147bhp

so i took the head off again and noticed the exhaust ports where white one side and black the other. I started asking questions on here, and puttign the big valves into a standard chambered head was a backward move for sure.

eventually found a 531 head.

The cam that was in the old head was scored to death on the bearings, and the head was scrap, it must have run dry when i was trying to start the engine at first, i had problems getting it running with the micro squirt. but anyway. I also found that 3 of the shims where not the ones that i had supplied, they where some inferior ones that had flattened too.


I stripped the motor, new oil pump, had the 531 skimmed, and a 0,5mm cometic head gasket, standard valves, new shims, and a t5 camshaft. I believed that this would do the big power as everyone went on about the 531 heads, but it did 160bhp at the flywheel.


so i think either ill get another 530 head, and have a go at it myself, maybe put the big valves in to it, new camshaft, and get it skimmed LOTS, or just get the 531 skimmed and try to port the exhaust ports.




i dont know what the differences are betweena boat 2.5 and my b230a, but my mate had a 2.5, 531 head skimmed lots, i think it was a k camshaft he said was in it, split 50 carbs, cast manifold, bigger downpipes, this was in his mk2 escort, and it made 156 bhp at the wheels on vince moselys rolling road. This is why before i was expecting my engine to have more power, and it completely didnt!
 
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I have a 530 head with 46/38 valves and it flows 210cfm. (12mm, 28")
I pay about 1k€ at this headwork (includes camshaft, that is custom grind made for my engine specs).

I had flowbench graphs somewhere, but i can't find those for now.
 
The 2.5 is a longer stroke to get the extra cc's. What is the maximum CC you are allowed?

Your big issue at the moment is lack of CR and poor flowing intake
 
thanks for the links, ill translate it all tomorrow, and read it!


cc, i think it jsut has to be 4 cylinder production engine. so i could go massive, but then the price is massive too.

of i just upped the compression, and left the head as it is, ill be up there? The inlet should do 190 bhp , is it the throttle size that restricts it or the runners?

thanks for the replies!
 
The normal thing to do is slap on a set of DCOE's that you can not do. The throttle plate is the biggest restriction of the factory intake

First step is going to be upping the CR
 
ive been told by a friend of a friend here, that i should get the bigger exhaust valve fitted only, the bigger inlet for me is too big.Then give the head to him and he will port the exhaust ports, do some chamber work, CC the head and give it me back for ?300-350. Then i can get it skimmed to the cc he says.

Im not sure what power difference that will make, but for the set up then i dont think the head will be the restriction. Im guessing on LH2.4 it wont be 190 bhp at the flywheel as everyone else has more work done and has 190 bhp.

Ive just got to price it up for what maybe be +20-30 bhp and a few hours work.
 
I'll chime in on the compression being too low. With that size cam I'd say cut a total of 3mm off the head and run the thinnest head gasket you can get away with, although that 0.5mm Cometic sounds a little thin to me.

I don't see where the A/F on this engine is stated during this dyno run?

We did 144whp with a K cam, totally stock manifolds, throttle body, etc, and some modest head work. About 2.5mm taken off that head and realistically, we could cut more, I feel the dynamic compression ratio is lower than it could be.

A lot of smack talked here about the B230F intake, and by looking at it, I tend to agree. HOWEVER, I have yet to see the Richard Holdener-esque back-to-back dyno test comparing that to the B21 intake, so until then, I'll withhold judgement.

If anyone has done this test, and it was JUST an intake swap, I'd like to put this one to bed.
 
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