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Best head for b23f na build?

Kjet revs to over 7000, 45's will have no trouble at higher RPMs. Dont forget suitable valve springs with the cam. Its a B23 so reving is no issue
 
This would probably be the best head for a NA B23. 8000 rpms, 231 hp (69 hp more than B230FT). Who says NA can't make power?

s-l500.jpg
 
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Depending upon your budget, sky is the limit.

However for a more realistic approach....

I currently run an 83 242 as my DD. 83 is the factory high compression 10.3(ish):1 motor than can actually use some camshaft.

I shaved a little bit when I replaced the HG a while back, so I'm a shade higher than that I suspect. I cleaned up the ports (carefully) with a carbide bit, mostly taking a tiny bit off the short turn. Lapped in the valves and installed new springs. New Elring HG with head studs (because I dislike TTY bolts).

Volvo H cam (largest factory cam). No hushers, just shimmed as tight as possible.

Stahl header, 2 1/2" exhaust with a Flowmax muffler.

Bosch bluetop 24# injectors (stock orange/yellow tops are 19#). Injectors are from a Ford 460.

M46. 3.31 rear axle (stock). Stock flat flywheel clutch.

Based upon my 84 242 TI car, I would estimate in the range of 130hp with this combination. Idle is lumpy for a 4 cylinder car. Many people ask me if I have a V8 in the car. At WOT above 3000 RPM, this combination gives a 11.5:1 AFR. The combination is fun to drive as it is. If anything I'd go to a 3.73 or 3.91 rear gear with a TruTrac to give it just a little more get up and go.

I'd agree on the manual conversion. The autotragic trans sucks a lot of HP to pump all that fluid that you just don't have to give.

The comment about the rev limiter is spot on with LH2. It fuel cuts at 5500 RPM. If you want to rev higher than that, you have to go to LH2.2 and pay someone to edit the bin on a removable chip 541 computer.

That or aftermarket EMS.

Not sure about the focus on revs. Any reason for wanting to rev it to the moon?
 
This would probably be the best head for a NA B23. 8000 rpms, 231 hp (69 hp more than B230FT). Who says NA can't make power?

s-l500.jpg

By 1992-93 season the typical good 240 with 2300 engine was making between 230 to 235 hp..8 valves, 7100 rpm..

That is 25 years ago...

And the were NOT on 45s...that limits the fun to around 210 max
48 DCOEs or Del-snort-os
 
By 1992-93 season the typical good 240 with 2300 engine was making between 230 to 235 hp..8 valves, 7100 rpm..

That is 25 years ago...

And the were NOT on 45s...that limits the fun to around 210 max
48 DCOEs or Del-snort-os

This all sounds like a beautiful song to my ears, but can a stock b23 shortblock withstand 7100rpm? Or it will fall apart after few hi rpm runs?
 
This all sounds like a beautiful song to my ears, but can a stock b23 shortblock withstand 7100rpm? Or it will fall apart after few hi rpm runs?

The b230 with "big" rods spun to 8k on a regular basis and lived most of the time over 5k.
Probably 1000-1500 rally stage miles like that.
After 3 years of rally abuse, that 180k mile motor is now going into another rally car.
 
Stock original motor you will probably spin a rod bearing eventually.

The b230 with "big" rods spun to 8k on a regular basis and lived most of the time over 5k.
Probably 1000-1500 rally stage miles like that.
After 3 years of rally abuse, that 180k mile motor is now going into another rally car.

so, one can assume its safer stay around 6000-6200rpm with stock internals..
 
so, one can assume its safer stay around 6000-6200rpm with stock internals..
You can bounce one of the limiter at 6200 for 500k miles. You start pushing things past 7k rpm you should have everything balanced, blue printed and in tip top shape if you expect it to last for a long time. Stronger H-beams are pretty cheap and pistons aren't too bad if you want some extra insurance/less rotating mass.
 
They take high RPM use fairly well. The rods are strong but heavy as are the pistons. On a budget just getting the engine balanced and make sure bearing fits are spot on etc. Valve springs will need to be strong enough for the higher RPM's. Many B23's have been subjected to high RPM use and they normally survive very well. On a higher buget longer H beam rods and shorter pistions would be a good bet. For a B230 I would strongly suggest H beam rods
 
You can bounce one of the limiter at 6200 for 500k miles. You start pushing things past 7k rpm you should have everything balanced, blue printed and in tip top shape if you expect it to last for a long time. Stronger H-beams are pretty cheap and pistons aren't too bad if you want some extra insurance/less rotating mass.

They take high RPM use fairly well. The rods are strong but heavy as are the pistons. On a budget just getting the engine balanced and make sure bearing fits are spot on etc. Valve springs will need to be strong enough for the higher RPM's. Many B23's have been subjected to high RPM use and they normally survive very well. On a higher buget longer H beam rods and shorter pistions would be a good bet. For a B230 I would strongly suggest H beam rods

no matter how much i would like to rev it past 6000rpm..i cant, or at least i see no point as my engine gets out of puff around 5500rpm.. probably because of the D cam.
 
no matter how much i would like to rev it past 6000rpm..i cant, or at least i see no point as my engine gets out of puff around 5500rpm.. probably because of the D cam.

I found that even a k-cam will still make power up to 7k if it's retarded a few degrees.
 
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