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low power output? b230a rally motor

Avtovaz said:
you can add to that list VAZ 2105 cam belt, its the same as the pinto one, and i asked for that in the shop to get " oh its the same as a pinto one !!!" LOL!

I think im going to get 0.040" taken from it, and itll be in the right ball park.
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Sounds good to me!
 
shoestring said:
These B230A/E pistons have my ears pricked up. KG advertises the dish as 0.6mm deep, and the F piston as 2.2mm deep. That would put the A/E volume somewhere around 2.5cc, all things being equal except the depth. If I fired a set of those in the B230FNA (that's the code we've given to the engine in the race car), we're talking 12:1. I like.

Do you guys know if the bore variations are the same across all versions of the same engine family? That is to say, is a "C" or "D" bore in my B230F the same as a C or D in a B230A/E? I would assume so, but I continually find that "they're all the same" bites me in the ass every time.
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I don't know about the bore sizing with the letters, but I do have a new set of 0376402 Mahle Original 96.610mm(cylinder diameter written on the box) B230A/E/K pistons here for measuring! The piston top has 96.59 stamped in the top. The piston's dish(approx. 69mm diameter near the top and 66mm near the bottom) does seem to be about .6mm(or a hair under) deep. Looking online I found https://www.autodoc.co.uk/mahle-original/2673405 that suggests it is indeed .6mm deep and 68mm in diameter. With that information, that calculates to just over 2cc of piston dish!

Here's a link to the other various B230F offerings(2.2mm dish, aka 8cc as you've measured assuming still a 68mm average diameter dish): https://www.autodoc.co.uk/car-parts/piston-10629/volvo/240/240-p242-p244/2764-2-3-i-cat
 

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With that information and assuming your piston height is 100% even with the height of the block?s deck surface, these are some compression ratios you could achieve with varying headgasket thicknesses and 41cc chambers(assuming 1mm/.040? additional removed from the head). I also threw in one example that is probably what I would run for a greater margin of safety at the bottom with 42cc chambers and a .030? headgasket.

13:1 with 41cc chambers and the .027? headgasket!
 

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well i took the head today, adn just asked the guy to take 1mm from it and ill measure what i have when i get it back on thursday,

ive been offered the 8th dec at 5:30 to get it tuned. I think it should be ok for then! wanted to make the sump bigger before then but may not have chance.

thanks for the help again!
 
Awesome! Well, you can always order a thicker headgasket to reduce the compression some if the torque is limited by fuel quality and detonation if the .027" is too much at 13:1 or so. If you're revving it over 7000 much, you'll maybe want the peace of mind of a .030"+ gasket anyway(although we've gone to almost 7200rpm with maybe even less clearance than you without an issue, so far!).

I look forward to hearing and seeing how it goes! If you could also take a picture of your ignition timing map once it's done, I'd enjoy seeing that.
 
do you use tuner studio? i can send the map over to you if you wish when its done!


I am hoping it wont be a >7k motor, more low down, umph out of corners, up hills, and force from a standstill...


have to see, maybe have to get the 5.0:1 back in it otherwise!
 
It probably won't make peak power above 6500rpm at the most, so you're probably fine there. It's just sometimes nice to be able to stay in gear and rev higher than 7000 than to upshift to only immediately downshift again.

I don't use tuner studio as I'm still using LH2.4, but a screenshot of the map would be fine!
 
a quick driver told me once, always change up if you can, and try to take the lock off as early as you can. i totally ignore this and hence why i need more power to make up for my mistakes lol


will take a pic mate! thanks for your help!
 
Avtovaz said:
a quick driver told me once, always change up if you can, and try to take the lock off as early as you can. i totally ignore this and hence why i need more power to make up for my mistakes lol
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Interesting! And, :lol:
 
so head skimmed, and the chambers are around 42cc now. So worked out that is about 12.6:1 now. The guy who skimmed it recons though that the exhaust port which i matched to the gasket maybe too big, he said you need a step between the head and manifold. too late now to change anything ! ;)

so ill get the head back together hopefully tomorrow, and then car running monday.
 
Sweet! And yes, normally you don’t want to gasket match the exhaust port on the head. The restrictions are above the valve, not at the port exit.
 
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To get a smooth transition again i'd also gasket match the manifold. The flat wall will otherwise get you quite a bit of turbulence.
 
well all going well we will find out how good my porting efforts are, all ive done is port the head, do a bit of chamber work and skim it. only time will tell now!
 
What your intake port looks?
It is very very important in na vehicles, much more important than exhaust.

It should look something like this:

 
is that a 530 head? mine is a 531, ive enlarged them to the gasket size. i think the intake is good flowing now.
 
SkeTchy-MechAniC said:
To get a smooth transition again i'd also gasket match the EXHAUST manifold. The flat wall will otherwise get you quite a bit of turbulence.
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Not the intake manifold, just the exhaust. It's ok if there's a larger opening in the direction of flow, it's not so ok if there's a smaller opening in the direction of flow.
 
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