Topic: Engine Building Question

This is not for a Lemons car.

I had to pull the engine out of my track beater last night. After the overheat (burst heater hose) at Road Atlanta, which was the second time that I've overheated it, I could get a .025" feeler under the straight edge on both the head and the block, so it's done. I tried putting a head gasket on it, but my oil quickly turned milky as my coolant level dropped, so I'm thinking that no amount or over-torqued head studs and copper spray is going to put Humpty back together again.

Engine is a Honda/Acura B-series.

Ring seal is still great and bores/skirts look good (it's only got a few thousand miles on it), but at some point in this engine's life (back in my drag racing days, boost!) it was decked several too many times, so piston-to-deck height is around -.027 (yes, that's a negative number). I compensated for this by using a .060 head gasket, which was probably a bit much, but I wanted to be really sure and it's my track beater, so I don't care so much about power as long as it runs.

It's also a Dart block, so I'm reluctant to part with it, as it is a really good block and I paid a lot for it.

So my first question is, can I just keep track of which piston went in which hole, have the head and block resurfaced, and slap it all back together with a new head gasket and a set of main/rod bearings and have a reasonable hope of still having good ring seal? Or should I get it bored/honed and put a new set of pistons/rings in it?

And my second question is, should I be worried about that 4-layer .060" head gasket? I've had several people tell me that they are failure=prone, but those have all been people who run 15:1 compression or 25+ PSI of boost. This is an 8.4:1 engine that I'm running NA on stock cams.

If that makes sense to anyone, then I'd enjoy hearing from you.

Thanks
Roger

Everybody grab your brooms, it's shenanigans!

Re: Engine Building Question

rmcdaniels wrote:

This is not for a Lemons car.

can I just keep track of which piston went in which hole, have the head and block resurfaced, and slap it all back together with a new head gasket and a set of main/rod bearings and have a reasonable hope of still having good ring seal?

Thanks
Roger

Assuming there is no cyl top ridge (prob isnt)

If you are careful you, could not only get away with taking it apart and reassembling, but, if the bearings are good, you don't really need to replace those either.

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Re: Engine Building Question

Stupid question, but as one who's done a lot of reading about piston/ deck heights and quench and whatnot...any chance you could either shave some height off the pistons, or find slightly shorter pistons? 

Seems like a shame to waste a good block with crappy squeeze, and if the quench is terrible to boot its going to be detonation-prone and pulling timing all over the place. 

Maybe de-stroke it slightly?  You could get an offset grind on the crank to knock 0.010 or 0.020 off the stroke, I think.  Or maybe shorter rods?  Just thinking about all of the geometry here. 

I wouldn't worry so much about the ring seal.  If it's low-hour then they'll probably be fine.

Tunachuckers: 10 Years of Sucking at Sucking
2008- 2010:  1966 Volvo 122, "Charlie"
2010-present:  1975 Ford LTD Landau...doesn't have a name?
2018:  1951 "Plymford".  Organizer's Choice - CMP Fall 2018 Hurricane Florence reschedule

Re: Engine Building Question

Team Infinniti wrote:
rmcdaniels wrote:

This is not for a Lemons car.

can I just keep track of which piston went in which hole, have the head and block resurfaced, and slap it all back together with a new head gasket and a set of main/rod bearings and have a reasonable hope of still having good ring seal?

Thanks
Roger

Assuming there is no cyl top ridge (prob isnt)

If you are careful you, could not only get away with taking it apart and reassembling, but, if the bearings are good, you don't really need to replace those either.

Agreed, unless in the overheating- turning oil-to milkshake event the bearings got wiped.

Tunachuckers: 10 Years of Sucking at Sucking
2008- 2010:  1966 Volvo 122, "Charlie"
2010-present:  1975 Ford LTD Landau...doesn't have a name?
2018:  1951 "Plymford".  Organizer's Choice - CMP Fall 2018 Hurricane Florence reschedule

Re: Engine Building Question

No ridges, this engine only has a few thousand miles on it; the pistons fall right out the top.

I was going to replace the bearings because they are cheap and I'm in there anyway. I'll throw a new oil pump in it for the same reason.

Quench would really be a matter of valve-head clearance. I was going to manage that with head gasket height because it's the easiest way. Cometic will make me a MLS gasket in whatever height I want for cheap, so if I'm .027 out of the hole and the piston manufacturer recommended clearance is .020 piston-to-deck with a .027 head gasket, then I really want .047 to the head, so I add that to my .027 and I want around .074, add whatever they have to mill to get the block flat, so maybe .080. It's an 8.4:1 engine anyway, it would be really hard to get any detonation on that in a Honda.

I've got nice forged rods and a forged hardened crank, so I really don't want to mess with those.

Milling the pistons is interesting, but again seems like more work/$ that a thicker head gasket.

Alternately I'm also considering a $300-$400 JDM B20 CRV engine, put a VTEC head on it, and eBay the old setup, but I have this high dollar paperweight sitting in my garage, so I wouldn't mind getting some use out of it.

Everybody grab your brooms, it's shenanigans!

Re: Engine Building Question

Everything you said makes sense.  The only issue is what you originally mentioned- at what point does the HG become too thick and prone to blowing out?  I know on our 460's Ford was chucking 0.060 gaskets at them to reduce compression (for NOx, back in the smoggy seventies).  I'd always thought that was a lot. 

You could probably mill the pistons on a drum sander.  ;-)  How far below the top of the piston is the first ring?

Your last overheating incident wasn't due to a blown HG, though, so maybe it's not a big deal.

Tunachuckers: 10 Years of Sucking at Sucking
2008- 2010:  1966 Volvo 122, "Charlie"
2010-present:  1975 Ford LTD Landau...doesn't have a name?
2018:  1951 "Plymford".  Organizer's Choice - CMP Fall 2018 Hurricane Florence reschedule

Re: Engine Building Question

@rmcdaniels

If the engine overheated the rings are shot and it would be a mistake to not replace them.When they get overheated they lose their tension and will not last. The bearings could be inspected and then use plastigage to check the clearance.If both look OK, then no problem to reuse them.As far as block/head warping, our rule of thumb was anything over 0.003" got resurfaced and anything over 0.008" was trash. When the head gets badly warped the cam bores are bowed too and if you surface the head you can make that flat, but the line bored cam bores will still be bowed. Back in the day there were machine shops that would heat the heads in an oven and then "bend" them back. You could probably save the block but I don't have high hopes for the cylinder head.

Re: Engine Building Question

Thanks, I'll check the cam bore alignment. There was no scarring or material transfer in the journals and they spin freely, so I'm assuming they are fine, but it's easy enough to measure them.

I've never seen overheating affect rings, other than physical damage from preignition or detonation, or if I get it so hot that there's material transfer from the pistons to the bores or the end gaps closed and broke the lands, but either of those cases would still be gross physical damage. I'll try the resurface/reassembly route and see what my compression/leakdown/vacuum numbers are before I go with a hone and new rings. If I have to replace pistons, then I may just toss this whole thing and go with an LS or B20 VTEC.

Everybody grab your brooms, it's shenanigans!

Re: Engine Building Question

I may have just figured out what is wrong with this thing. I think it's got a B18A/B (89mm) crank in it. The pistons are right where they would be if I use 89mm for my stroke. If I use a B18C (87.2mm) crank, then that should drop them down to .020 in the hole, which is exactly where they should be. If that's the case, then the block is fine. Unfortunately this engine was built over ten years ago and I can't reach the guy who designed and built it, so I'm doing some guessing. When I get back from Belgium, I'll measure it.

Everybody grab your brooms, it's shenanigans!

Re: Engine Building Question

Being "Not a Honda Guy" I didn't even think about this, but it sure makes sense.  Hope that turns out to be the case!

Tunachuckers: 10 Years of Sucking at Sucking
2008- 2010:  1966 Volvo 122, "Charlie"
2010-present:  1975 Ford LTD Landau...doesn't have a name?
2018:  1951 "Plymford".  Organizer's Choice - CMP Fall 2018 Hurricane Florence reschedule

Re: Engine Building Question

Yeah, I was assuming that the builder used the crank/rod combo that matched the block, but if not, then I've got a lot more options if I just put a B18C crank in it. I could pop a set of cheap shelf-stock pistons in it and bump the compression a bit, or do a .5mm overbore and basically have a fresh engine. I'm not 100% on that and won't be for a couple of weeks, but the math works perfectly. It makes me want to go back to Raleigh this weekend and check it out.

Everybody grab your brooms, it's shenanigans!

Re: Engine Building Question

Late to the game, but flycutting pistons isn't a big deal at any race engine machine shop that doesn't also double as a meat market.(ie they're butchers)

Along the same lines, they can also simply increase the valve reliefs, if they even need it.  This is where mocking it up and turning it over with the ole' clay/silly putty gives you the actual clearance you have to work with.  S/F....Ken M

Re: Engine Building Question

echosixmike wrote:

Late to the game, but flycutting pistons isn't a big deal at any race engine machine shop that doesn't also double as a meat market.(ie they're butchers)

Along the same lines, they can also simply increase the valve reliefs, if they even need it.  This is where mocking it up and turning it over with the ole' clay/silly putty gives you the actual clearance you have to work with.  S/F....Ken M

I have used grease, or Play-Doh.  Both worked well.

Tunachuckers: 10 Years of Sucking at Sucking
2008- 2010:  1966 Volvo 122, "Charlie"
2010-present:  1975 Ford LTD Landau...doesn't have a name?
2018:  1951 "Plymford".  Organizer's Choice - CMP Fall 2018 Hurricane Florence reschedule

Re: Engine Building Question

After tearing it apart, some time in the past 10+ years water sat in #4 and rusted it badly:

http://www.carolinahondas.com/members/roger-albums-pj-picture6739-bad-hole.jpg

I just dropped it off at the machine shop for an overbore to fit a new set of oversize pistons. I ordered shelf-stock Wisecos with a mild dome, which should net me 11.47:1. I've talked to two engine builders who said that a tall head gasket should work fine for this build, and apparently shelf stock forged pistons already have slightly oversized valve reliefs, so that should be fine also. The machinist will check the cam bores, and he's got the equipment (apparently a big oven with a jig that he can bolt the head to) for straightening it if necessary.

This is probably better, an 8.4:1 all-motor Honda engine kind of sucked anyway:

http://www.carolinahondas.com/members/roger-albums-pj-picture6738-slugs.jpg

Everybody grab your brooms, it's shenanigans!

Re: Engine Building Question

That looks like class A all day long!

Re: Engine Building Question

Yeah, those pistons would exceed the budget by themselves.

Nope, I am firmly committed to class C at this point. After they boot us to B in the 240D, I already have the next awesomely horrible pile of steaming magnificence in the works.

Everybody grab your brooms, it's shenanigans!

Re: Engine Building Question

rmcdaniels wrote:

Yeah, those pistons would exceed the budget by themselves.

Nope, I am firmly committed to class C at this point. After they boot us to B in the 240D, I already have the next awesomely horrible pile of steaming magnificence in the works.

This brings me great joy to read.  Welcome to the slow kids' club.

Tunachuckers: 10 Years of Sucking at Sucking
2008- 2010:  1966 Volvo 122, "Charlie"
2010-present:  1975 Ford LTD Landau...doesn't have a name?
2018:  1951 "Plymford".  Organizer's Choice - CMP Fall 2018 Hurricane Florence reschedule

Re: Engine Building Question

mechimike wrote:
rmcdaniels wrote:

Yeah, those pistons would exceed the budget by themselves.

Nope, I am firmly committed to class C at this point. After they boot us to B in the 240D, I already have the next awesomely horrible pile of steaming magnificence in the works.

This brings me great joy to read.  Welcome to the slow kids' club.

We got rid of our competitive class B car to chase IoE's (two in the bag).  Then we kept improving the Dustbuster until now the only thing holding it back from winning class C is the drivers or freak accidents like a Chrysler turbo 4 lasting a whole race with no issues.

It really is more fun if you don't take anything too seriously.

Re: Engine Building Question

mechimike wrote:

This brings me great joy to read.  Welcome to the slow kids' club.

You going to be at CMP this year? We'll still be in the 240D/300D next month and gunning for our first C win, but I've got a surprise for the Fall race that I think will be epic.

Everybody grab your brooms, it's shenanigans!

20 (edited by mechimike 2018-03-30 04:12 AM)

Re: Engine Building Question

We're definitely going to miss the May race.  The original plan was for September this year, but now that's getting questionable.  We've had some major house projects that have eaten up all of my time.  The LTD sits forlornly sort-of half sticking out of my comically small garage.

This could be the first year since 2008 that we've not done a race.  :-(

Tunachuckers: 10 Years of Sucking at Sucking
2008- 2010:  1966 Volvo 122, "Charlie"
2010-present:  1975 Ford LTD Landau...doesn't have a name?
2018:  1951 "Plymford".  Organizer's Choice - CMP Fall 2018 Hurricane Florence reschedule

Re: Engine Building Question

Mechimike, you have e-mail.

Everybody grab your brooms, it's shenanigans!