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Low Friction B230 Engine Opinions

FreeEMSFred

New member
Joined
Nov 2, 2009
Location
Kiwiland
I have a "low friction" early B230 (B230K carby with heron heads, to be exact, but probably not relevant) that I'm not sure what to do with.

I bought the car it came in with "bad knock" and promptly convinced myself that it was a low-friction bearing failure. Turns out it was something steel dropped into the carby at some point and found its way into cylinder 4 where it did a fair bit of damage.

Although I've not cracked the caps just yet, the engine has 300,000km on it and I couldn't detect any play in the big ends by rotating the crank back and forward. IE, it's probably fine even with highish mileage.

So the questions are:

1) Are these engines really that bad? Or is it all/mostly internet/FAQ hype?
2) Or is it just in turbo applications that they don't hold up?
3) Any info on the friction difference in terms of torque or power with all else equal?

And the final one:

Do I keep it and put a 16v head on it and use the low friction properties to make a little better power than the later/better engines can in a naturally asphyxiated way? Or do I pull a few bits off it and send it to be turned into shipping containers and caster wheels in China? And bide my time for a third squirter block.

I'll probably pull the pistons/rods/crank out of the block the night after tomorrow and can post pics of the bearings then.

Any and all thoughts on low-friction vs later B230 engines welcome!

Chamber/piston pics for amusement:

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And a couple of teasers for another thread I'm yet to start:

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Again: Any and all thoughts on low-friction vs later B230 engines welcome! Cheers! :-)
 
The low friction bottom end, much maligned on TB as "weak and worthless"..... however try and find proof of any crankshaft/main bearing failures.... and you'll fail. Tis always the skinny rods that get the crooked finger pointed at them. If you search a bit, you'll find plenty of powerful 4 bangers with 55mm main bearings. One Swedish lament I found about said engines pointed directly at the "stakes" as the failure point.

Note: in true TB fashion, the locals will come out 98% AGAINST the scrap metal low friction bottom end...... get ready for it.
 
The low friction bottom end, much maligned on TB as "weak and worthless"..... however try and find proof of any crankshaft/main bearing failures.... and you'll fail. Tis always the skinny rods that get the crooked finger pointed at them. If you search a bit, you'll find plenty of powerful 4 bangers with 55mm main bearings. One Swedish lament I found about said engines pointed directly at the "stakes" as the failure point.

Note: in true TB fashion, the locals will come out 98% AGAINST the scrap metal low friction bottom end...... get ready for it.

+1!

I will also add that it's a question of how far you want to go. If gains well into the high 200's are what you're after, you'll be fine. Make sure all sensors are up to snuff (knock and coolant temp sensors) and avoid detonation.
 
I used a center thrust engine for the last NA rally engine I built. Specifically for the smaller mains (which are still pretty big).... and because there was a 86mm stroke crank available locally for $200... and no one wanted it because it was for the "weak" redblock... hahaha.
I converted the 180deg center thrust to 360deg by simply machining the main cap and adding a second set of bearings. Probably not necessary in retrospect. The car doesn't spend a lot of time waiting at traffic lights with the clutch pedal depressed....
Currently makes about 200hp and spins to 7.5k on the regular.
 
I was pushing about 260 flywheel hp out of my old '85 740t with the weakest of all the weak red blocks. Besides some piston slap when cold, it ran strong. Took it to the drag strip 6 or so different times with at least 6 runs each trip, best time was 13.8 @100.5. There were times where I ran it hard, but didn't purposely beat the crap out of it.
 
Could you fill us in on the details of your motor build?

16v head, flat top pistons, 86mm crank, reground cams (11.3mm lift/276?, 235?@.05in), shortened stock intake that had the runners opened up.

It's never been on a dyno and has about 2-3 hours of street tuning. It's as fast as my b230ft car @15psi (IPD cam, 2.5in exhaust, mildly ported head that was shaved .030in). They're both equal to about 80-90mph.
The engine is capable of a lot more if we ever get time to tune it properly.
 
Id like to see what the ports look like on those heron heads... with the lower valve surface there should be sufficient room for a nice short side radius on the exhaust side.
 
One Swedish lament I found about said engines pointed directly at the "stakes" as the failure point.
Can you explain what "stakes" are, please?

Note: in true TB fashion, the locals will come out 98% AGAINST the scrap metal low friction bottom end...... get ready for it.
I was ready for it before posting, but the thread has been largely pleasant and useful :-)

I will also add that it's a question of how far you want to go. If gains well into the high 200's are what you're after, you'll be fine.
Nah, high 100s to low 200s is what I'm after if I keep it. If I do keep it it'll likely end up in NA 16v trim and stuffed into my 360 hatchback with the 360 alloy sump and short water pump, and some reground cams and ITBs.

Make sure all sensors are up to snuff (knock and coolant temp sensors) and avoid detonation.
I'll validate any sensors I end up using as part of the install of FreeEMS onto it - standard procedure. Knock control is good if you've got shady fuel supply, but ours is pretty consistent from my experience. At high power levels it's near useless, but I won't be going there.

I used a center thrust engine for the last NA rally engine I built. Specifically for the smaller mains (which are still pretty big).... and because there was a 86mm stroke crank available locally for $200... and no one wanted it because it was for the "weak" redblock... hahaha.
Things I've learned since posting this thread:

1) Rod bearings are NOT smaller (and I've never heard of any reasonable engine ruining main bearings without undue cause)
2) Rods are thinner (I had forgotten this, and didn't realise it was 1:1 correlated with the bearing size change) and if the bolts are the same then this implies higher RPM before failure of a rod bolt
3) Thrust bearing is a perceived issue
4) People get high mileage out of them no worries, eg double what any of my Volvos have on them

I converted the 180deg center thrust to 360deg by simply machining the main cap and adding a second set of bearings. Probably not necessary in retrospect. The car doesn't spend a lot of time waiting at traffic lights with the clutch pedal depressed....
Currently makes about 200hp and spins to 7.5k on the regular.
None of my cars spend a lot of time with the clutch pedal depressed - that's bad driving! :-D USA spec clutch starter lockout probably has a significant role to play, too. Starting an engine with end load is not good for them, but once there's some oil pressure and flow...

I was pushing about 260 flywheel hp out of my old '85 740t with the weakest of all the weak red blocks. Besides some piston slap when cold, it ran strong. Took it to the drag strip 6 or so different times with at least 6 runs each trip, best time was 13.8 @100.5. There were times where I ran it hard, but didn't purposely beat the crap out of it.
Thanks, good data point! :-)

16v head, flat top pistons, 86mm crank, reground cams (11.3mm lift/276?, 235?@.05in), shortened stock intake that had the runners opened up.

It's never been on a dyno and has about 2-3 hours of street tuning. It's as fast as my b230ft car @15psi (IPD cam, 2.5in exhaust, mildly ported head that was shaved .030in). They're both equal to about 80-90mph.
The engine is capable of a lot more if we ever get time to tune it properly.
Now that's what I'm talking about. Along the same lines as what I'm thinking, but more extreme :-) Thanks! :-)

Id like to see what the ports look like on those heron heads... with the lower valve surface there should be sufficient room for a nice short side radius on the exhaust side.
Would a cross section work for you? I think I can find a bandsaw to use. Do you want any particular photo angles first? Not sure when I'll get around to it, but I'll post here if/when I do.

So it seems like I should keep and use this bottom end for my one-day-DOHC 360, then. Any objections? :-)

360 thread: http://forums.turbobricks.com/showthread.php?t=337517
 
Can you explain what "stakes" are, please?
If google translate was used to read said forum post, I'm guessing "stakes" = "stakar" = connecting rods

Nah, high 100s to low 200s is what I'm after if I keep it. If I do keep it it'll likely end up in NA 16v trim and stuffed into my 360 hatchback with the 360 alloy sump and short water pump, and some reground cams and ITBs.

Just slapping a 16v head on a b230k engine would be a pretty bad idea. The 631 head from a k-engine is completly flat (heron head) the combustion chamber is all in the pistons. I'm guessing a b230k with 16v heads would have a compression ratio somewhere in the neighborhood of 6:1:-P
 
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If google translate was used to read said forum post, I'm guessing "stakes" = "stakar" = connecting rods
Ahhh, thanks! :-)



Just slapping a 16v head on a b230k engine would be a pretty bad idea.
Yup, sure would! :-D

The 631 head from a k-engine is completly flat (heron head) the combustion chamber is all in the pistons. I'm guessing a b230k with 16v heads would have a compression ratio somewhere in the neighborhood of 6:1:-P
Good thing I have a spare set of B234F pistons/rods for the task, then. Just a hone and some gaskets and so forth away from a usable engine :-)
 
Forgot to post this earlier:

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Hilarious, right? :-D

Didn't get the block stripped tonight, but did crack the tension off all eight 12 point 10mm head rod bolts and
may continue tomorrow, though it might be the right night for more ambitious tasks if I can find some help :-)
 
I used a center thrust engine for the last NA rally engine I built. Specifically for the smaller mains (which are still pretty big).... and because there was a 86mm stroke crank available locally for $200... and no one wanted it because it was for the "weak" redblock... hahaha.
Given the stroke difference, I'm guessing you ran a longer rod, but curious as to whether you used the stock rods. Which rods? EDIT: Actually no, with same deck height you'd already be pushing the pin height up using stock rods. Still curious as to what you did exactly :-)

I pulled the pistons and rods earlier, and they're quite cute - very low windage and reasonably stout, yet probably light enough to spin 8k on stock stroke with stock bolts. Win?

Main caps are free of bolts, time to pull them, and the crank, rinse it, and find somewhere to store all of it for a while.
 
Caps and crank removed from the block, bearings in reusably good condition, thrust bearings included. Which you'd expect from an auto with almost zero end loads, I suppose, but still, 300,000km+ on this (speedo stopped long before I got it). Rod bearings not so much, but not all gone as I was supposed to be expecting.

My own personal summary now that I've had it apart:

1) Rods are fine for NA use, probably better than the 13mm varieties due to lower mass and thus lower stress on rod bolts at higher RPM levels.
2) Thrust bearings a non-issue for automatics, and probably not a huge deal for non-USDM spec cars with manuals and intelligent owners, either. Manual USDM cars could have issues because of brain-dead government regulation.
3) Main bearings complete non issue, period, though if you were trying to push big numbers, the bigger ones are a better choice, obviously. High ZDDP content synthetic oils FTW, regardless.

In summary, I'll keep it and put a 16v head and some cams on it with stock B234F pistons and probably the lighter rods, possibly with ARP bolts. One day, but not anytime soon, that's for sure.

Pics when I get a chance, maybe later tonight, though I'm doing an engine swap this weekend... ;-)
 
Given the stroke difference, I'm guessing you ran a longer rod, but curious as to whether you used the stock rods. Which rods? EDIT: Actually no, with same deck height you'd already be pushing the pin height up using stock rods. Still curious as to what you did exactly :-)

I pulled the pistons and rods earlier, and they're quite cute - very low windage and reasonably stout, yet probably light enough to spin 8k on stock stroke with stock bolts. Win?

Main caps are free of bolts, time to pull them, and the crank, rinse it, and find somewhere to store all of it for a while.

Stock b230 rod length. Switched to MaxSpeeding (aka eBay) rods with ARP bolts. Dropped some weight over stock. Pistons are custom JE. 400g per.
 
Install flat tops in super thick sleeved bore ~91-92mm bore B200 block, deck block, install 631 interference "heron" head, convert to diesel with 86mm crank :lol:

I was always curious about the exhaust port as well, that being the big choker on the 8V heads.

Cut a cross section, yeah.

The big argument against is that it's interference and that pistons get awkward in design and usually heavy. Big argument for is that the valves are completely unshrouded (for better and worse) with the pistons at much of anything but TDC , and it's detonation resistant for running ~10:1 compression with the miserable complicated Solex carb those things got and sipping fuel when in good repair like a carbed tercel :lol:.
 
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If one of you weirdos wants the head, it could be repaired. It doesn't have to become recycling fodder. I prefer more Valves... ;-)

culberro, do you know what your static compression ratio is?

Gave the block a good clean and some light oil to keep it fresh in storage. Some pics of carnage, good bits, and clean block:

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