low power output? b230a rally motor

It's not cold...yet. I can see it hiding around the corner.

It would be great to have some more info on the cam. Tried to ask the specs from KL again but they ain't helpful at all!

so the head gasket is 0.68mm, slightly thicker than i thought but not that much! the pistons are dished and only come flush with the top of the bore. I think the dish is 3cc but not sure.

I havnt got the chart of the air fuel ratio, but my mate has told me that chris aims for 12.5:1. i have not much idea of what that means in relation to what i have...

Not sure of the timing, i can download the map for tuner studio, but im not really into that side of things...

we moved the cam 4 degs advanced and retarded from where i had timed it in, and chris said i had got it spot on, and there was no more power to be gotten out of the engine.

the head swap is only because if i port the 531, and i mess it up, ive got no 531 to go back to, so i was thinking of new cam and the 530. But reading now, i think the thing is take teh 531 off again, measure what i have CC in the head etc, and skim more.

But every time i take it to chris, its ?150-200, and a day off work, its not that dear, he is good, but this would be the 5th time its been there, so ive spent ?1000 with him!!

i have emailed kl racing about another camshaft i had, and they basically said they had no idea, let you r engine tuner work it out.


So the main difference between my engine and my mates boat engine is 200cc and his induction, he had split 50;s.

There is no european version of the lh2.4 that i could have that is smaller, or something liek that? Its just so strange its not making power.



not a very good vid, but on some pics i have i can see its saying 12.5:1 arf

CLICK HERE

Ok. If your pistons are flush with the top of the bore, your headgasket is fine. I would be curious to know what the volume of your combustion chambers are, but I can't explain the low power, even if your compression is a little low. 12.5:1 AFR should be fine. It may make a little bit more power with it leaner, but not much.

You may not need to tune the fueling much more after doing some more head work, it may be ok as is(ignition may want less advance, depending on what it currently is, but if it leaned out to 13:1 AFR it wouldn't be the end of the world).

Can you confirm that you're running a Microsquirt for fuel tuning and a LH2.4's factory EZK for the ignition side of things? Is the ignition timing changed from stock or has that not been touched yet? I don't expect you to pick up power if it's still stock, but it might prevent you from blowing it up if it's still too advanced.

the microsquirt controls everything, sorry i should have said before, its got a bmw m54 front pulley on it, cosworth crank sensor, no cam sensor, tps, gm 3 bar map sensor, intake temp sensor, coolant sensor, and thats about it.

So its all fully mapped

Ok, so LH2.4 is not restricting you in any way. It should have more power...!?

See my notes in red.

Avtovaz said:

one thing i have noticed also is you run 92 octane fuel, we have 95 and 99 available here, and i can use an octane booster if i wish also. But however, means my 160 bhp at yours would be like 150! Is the 531 unleaded too? i never thought about this before! - Our 92 octane fuel is basically equivalent to your 95 octane fuel. Our engine has been able to run ignition timing more advanced than needed for MBT(maximum brake torque), so we are not limited by our fuel's octane rating. At least, not with our single Singh groove and 11:1 compression with the ENEM K13 camshaft. We haven't had the car back on the dyno with the 11.7:1 compression and ENEM C2(copy) camshaft to dial it in any further and I haven't changed the ignition timing between the two setups.
[...]
with the exhaust ports, is there a mod i can do that makes a big difference with out being hours of messing? As in, if im going to at best get 190 bhp out of it, can i get nearly there myself? - I don't think you necessarily need to go crazy with it, just make sure the area beneath the valve is opened up to 86-88% of the valve diameter and blend it in nicely? Ask Robert for more detail and/or look at Erland's webpage I've linked in one of these recent threads. Robert did some clean up on our head with some suggestions from Erland.

With the cast manifold also, is there a place to take metal from and not too? - Anywhere that is a road block to flow, sure? You can gasket match the exhaust manifold's inlets(don't gasket match the head) and you can open up the outlets a little, but make sure the exits are the same diameter as or smaller than the inlets to your downpipe.

how come some of the factory cams can make such big power? The K cam i hear is good. They are ok, and depending on the setup can make 150whp. Typically, they make less than 135whp unless a lot more work is done.

My mates boat motor was 2mm from the 531, cast exhaust manifold, k cam, 2500cc, split 50s, 156 at the wheels. Those additional 200cc means he is running a lot more compression than you, assuming his piston dish is similar to yours. He's cramming another 200cc of air/fuel into a smaller combustion chamber than you. On top of that, he has MUCH, MUCH better intake flow through those 50mm carbs. If he put a larger camshaft in there and took even more off the head, he'd have closer to 180-200whp depending on his choices.

Click to expand...

Jussi Alanko said:

Your cam is good for at least 200whp. It is NOT good for 200whp. It might be ok for 200hp or just over in the right setup, but definitely NOT 200whp. It is not 300? of duration at 1mm of lift or .050" of lift. It's not as aggressive as you think.
What you need is a head flow, in na-engine especially intake flow.
You need to port that 531 and change valves to 46/38, porting is difficult without experience or flowbench, so you need to find a speed shop that made porting to you, they usually give you flow rates as well. - Yes, I agree you can make more power with 46/38mm valves and everything else set up properly, but I can also tell you that you can make 180whp with STOCK sized valves.

Click to expand...

Avtovaz said:

What is the best cam to go for if i wanted low end power? Maybe what you have is ok for low end power, you just need more compression? Otherwise, something with good lift but less duration. Our ENEM K13 camshaft did great torque and a super wide powerband in the race car. It's a little bit more aggressive than the K and H camshafts that also have wide powerbands.

Click to expand...

If you want torque, you need compression. Pull the 531, unshroud the valves a little on the intake and exhaust side, shave maybe another .7-1mm off or so, do a little port clean-up on the exhaust and maybe intake if there's anything really there to clean up, and run it as is. Verify the pistons don't stick up out of the bores any, as a .027" gasket might be too tight if they do for 7500rpm. Based on your dyno plot, it seems like either something is not flowing as well as it should, or this camshaft is actually quite small even though it is advertised as being relatively large. Your powerband is reasonable, it just seems like it should be showing WHEEL power and torque readings, not ENGINE readings.

right thankyou ! this time itll have a standard type head gasket on it i think the cometic one has been on the 530, then the 531 2 times now, so im not convinced its a wise move to use it again.

I have had to re read every word you have said mate, maybe 20 times, and then it clicks. Ill try to get the head off this friday, and at least measure it and report the results with pics hopefully.


One thing Vince who rolling roaded my mate rogers car said about his engine was that they seemed not able to get enough air into it, fuel was ok, but a good flow of air in, it just wanted more and more. He was on the factory dizzy and coil. His split manifold was a volvo carb manifold with plates welded onto it.


Oh also, my sump is standard, down the lanes i go there isnt any hard cornering like on a circuit, but maybe also id like to sort something out with the sump too, any suggestions please?

thankyou oh so much, i was very nearly thinking of buying back my old bmw engine, but didnt want to.

Avtovaz said:

right thankyou ! this time itll have a standard type head gasket on it i think the cometic one has been on the 530, then the 531 2 times now, so im not convinced its a wise move to use it again.

I have had to re read every word you have said mate, maybe 20 times, and then it clicks. Ill try to get the head off this friday, and at least measure it and report the results with pics hopefully.


One thing Vince who rolling roaded my mate rogers car said about his engine was that they seemed not able to get enough air into it, fuel was ok, but a good flow of air in, it just wanted more and more. He was on the factory dizzy and coil. His split manifold was a volvo carb manifold with plates welded onto it.


Oh also, my sump is standard, down the lanes i go there isnt any hard cornering like on a circuit, but maybe also id like to sort something out with the sump too, any suggestions please?

thankyou oh so much, i was very nearly thinking of buying back my old bmw engine, but didnt want to.

Click to expand...

Well, you don't want to go to a stock headgasket because it's .047" thick instead of your current .027" and will take you out of the ideal piston-head quench clearance range of .030-.040". The tighter it is, the higher your compression is, too. We're running somewhere around .025" clearance right now(at least on one cylinder) and haven't had an issue so far that I know of up to 7100rpm. Our .036" gasket has been used three different times now as well, and so far it's ok. We use Hylomar or a copper coat on it to try and help it not be an issue. So far, so good and we have three races on it this year since it was last apart.

If you want more reading, and more reading of basically the same stuff, check here and here if you haven't already.

Here's a recent thread on oil starvation.

Your old BMW engine is likely a better engine, but obviously smaller. You could bump up the compression in that to get some more torque and such, but you may or may not come into issues with detonation depending on how that engine likes things and what gas you can run.

thing is the bmw engine was good, it was all revs, and i wanted to get more low down power out of the car. I was told that going to the 2.3 instead of the rear wheels lighting up when its lost grip a bit, the 2.3 would kinda just take it more in its stride.

the bmw engine also, it had all these plastic water manifolds on it, and i still think the volvo motor will make it a better car.


.. hopefully!


it did go ok though ! click here


i have a spare block, so hopefully ill get the sump off that tomorrow and have a look at that. my car has abs with the same map as the touring cars had in the uk, the brakes are unreal, and i think as im braking the oil is going forward in the sump, so defo dont want any further problems.

quite worried about modding it though, i put a xe into my lada, and i took one of the sensors out one day and there was a bit of spatter on the end of it, could have done a lot of damage.


would you also know, the dish of a b230a engine piston if its 3cc?

thanks again.

I don't have any experience with the B230A pistons, sorry!

Avtovaz, where do you live?
You only need three things!

Cylinder head that flows about 200cfm, that is a peace of cake at experienced porter.
Then you need compression 12:1 or bigger.
Then you need a camshaft that works in high rpm.
Also you need a intake flow, if you use microsquirt, you could use these:


Those costs about 300$ in alibaba.

Jussi , those arnt allowed for my rallying, the idea is to limit the power down!


I have just measured the head, the chambers are 47cc, and i think the ratio is 11.5:1, not as low as i thought, so dosnt quite explain the low power, but have to port the head a bit and see what happens.

Can you verify the piston - deck height? I think you said it was near zero. Also verify the piston dish volume if you can while the head is off. Using the zero deck height, .027" headgasket and 3cc for piston dish, I also came up with 11.5:1 compression currently.

https://www.csgnetwork.com/compcalc.html

This is the one I like too.

The MM/Inches conversion makes it handy, haha.

yes, so ive got the head ported, and i did some of the chamber work tonight too, they are looking to be around 47.5-48cc atm, will have to remeasure. Then ill have a look at the exhaust manifold, get the head skimmed and put it back together.


when the head is done ill post some more pics, then decide where to go with the amount off!

thanks again for the help.;

I hope it will do the trick! Definitely confirm piston location and dish volume before deciding on how much to remove from the head.

Are you definitely going to use a stock type headgasket still, or will you be going to another thinner gasket?

Looking forward to some more pictures and the final result!

maybe also have a go at gasket matching every transition going from intake >> head >> exhaust
Every edge standing proud in the airstream is an obstruction and will hurt flow.
I don't know if you are using the stock volvo airbox but in stock form that is also restrictive. Remove the cold weather airflap and drill lots of holes in the bottom of the airbox (that's pre-airfilter!)
Is the engine still using the idle air control valve? What is it doing at wide open throttle? Is the ECU opening that thing up as well? Maybe that can be used to get in some more air?

yes will measure everything defo, and ill be asking for advice before the skim for the right CC for the cam etc, i have no idea! The cometic head gasket looks ok, ill clean it up and that can go back on. i was just worried with this being its 4th time! Having said that, the price of the new gasket and the price of a "DNF" [did not finish] on a rally, the price of a new gasket wins. but will see what its like close up first.



jan, i can match the head>> exhaust, but modding the inlet is not allowed for the rallying i do, so ill leave that well alone... no mods to the inlet what so ever, not one... id never do such a thing.


... ever.


ive got an elbow comming from the inlet, into an ally pipe up to a cone filter to where the bmw ps pump is mounted on my set up. so there is no volvo parts there after the inlet. The idle valve, i had problems on a rally once with this, i think it was a Chinese copy part, i blanked it off, and the engine idled better and the tuner didnt take the extra time to sort its tune out.

thanks again for all the advice!