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Rebuild
Posted: Mon Dec 31, 2012 5:12 pm
by Daniel2019
This is potentially a really stupid question but meh!
Basically, with this rebuild of mine, what exactly do I need to be done to the heads and block? Apparently my project 6A12 had a blown head gasket (although the gaskets looked OK to me). What exactly do I need to be asking when I speak to a shop? I dont want to be doing the same thing Im doing here (herp derp what do?) because then "he's retarded, lets charge him more!"
Try to keep the smartass answers to a minimum please (unless its really funny

), I'm trying! (Ive cleaned it all up and I believe its all ready to be sent off to a shop so I dont think im doing too bad considering!)
Re: Rebuild
Posted: Mon Dec 31, 2012 7:40 pm
by vipfto
pretty much tested for cracks get it cleaned down. If you can afford certainly suggest getting skimmed ported and polished
Re: Rebuild
Posted: Mon Dec 31, 2012 9:16 pm
by spetz
What pistons will you run?
You'd probably need he cylinders checked for size and then bored/honed but this depends on your pistons.
Re: Rebuild
Posted: Tue Jan 01, 2013 2:14 am
by Daniel2019
Pistons are stock 6A12 MIVEC ones.
Was just going to clean the old ones up in kero and put them back in with new piston rings (although the piston rings that are on it seem to be fine). Or should I be looking at something else?
I basically just want a (close to) new stock 6A12.
Re: Rebuild
Posted: Tue Jan 01, 2013 6:19 am
by spetz
Well, without knowing how your cylinder walls are and pistons are, you can't make that plan.
You should check that after a hone the gap between piston to cylinder is not too much, otherwise this is what oversize pistons are for.
If you have the block at a machinist, ask if you can bore the cylinders enough to use 81mm pistons (from a 4G93). This way you could have 2.2L
I've download this movie using torrents, and it was really helpful to understand what goes into a rebuild:
http://store.boxwrench.net/Basic-Engine ... D_p_8.html
Re: Rebuild
Posted: Tue Jan 01, 2013 8:04 am
by Daniel2019
Yeah I was kinda wondering how stocks would work if they have to do that. Cheers for the info spetz and tim
vipfto wrote:pretty much tested for cracks get it cleaned down. If you can afford certainly suggest getting skimmed ported and polished
What would be a fair price for this?
And also what would be a fair price for boring it out to a 2.2?
Re: Rebuild
Posted: Tue Jan 01, 2013 8:23 am
by spetz
Post and polishing can range from a few hundred for a few thousand. Keep in mind if it's poorly done (ie, cheap) the head may flow worse than before.
A good guide is that port and polish + service the 2 heads will be about a 2K job if done properly.
Boring the cylinders shouldn't be too expensive. Pistons should be ok too (4G9X series fit into a 6A13 so should fit into the 6A12. Also the 4G91 has 78.4mm bore which would be the same pistons as the 6A12) but the issue is the cylinder wall may become too thin and won't be safe to run.
The wall would be 1.3mm thinner to accommodate 81mm pistons, giving 2,133cc
With 82mm pistons, 1.8mm thinner cylinder wall, you'd get 2,186cc
It may be more trouble than it's worth, as you'd at least want to strengthen the stock rods (I read cryogenically treating them and shot peening etc can give them roughly 15-20% more strength)
The possibilities are endless but it all comes down to cost.
Re: Rebuild
Posted: Tue Jan 01, 2013 8:32 am
by Daniel2019
All im basically looking for is a rebuilt basic 6A12. As much as I would like a port and polish done, a 2.2 with brand new pistons etc. etc. done, I just dont think I want to drop all the money into it because ive never done a rebuild (or anything like this) before and I dont want to have fucked something up along the way, only to not get it running and waste a bunch of cash.
As far as I can see, what would be suited to me would just be a rehoning of the cylinder heads, get both the heads and block checked for cracks and have it all cleaned down properly, then throw a coat of paint on it (just because) and begin constructing the engine again while replacing everything (gaskets, seals, piston rings etc etc.) on the way.
Re: Rebuild
Posted: Tue Jan 01, 2013 8:47 am
by ZFL45H1
Daniel2019 wrote:
As far as I can see, what would be suited to me would just be a rehoning of the cylinder heads, get both the heads and block checked for cracks and have it all cleaned down properly, then throw a coat of paint on it (just because) and begin constructing the engine again while replacing everything (gaskets, seals, piston rings etc etc.) on the way.
This is exactly what I did get everything professionally looked at and cleaned and use all new parts and I mean everything even if they look good, your goin to all this trouble it would be a shame for something to break in a few thousand kms but u can still use same pistons conrods and valves as I did my rebuilt engine is still goin nothin wrong with it (besides i used the wrong sealant around the sump which I'll fix next oil change)and it cops a caining most of the time

prob done 15k-20k
Re: Rebuild
Posted: Tue Jan 01, 2013 8:55 am
by Daniel2019
Hey ZFL45H did you get any other part of it professionally done? Also if you dont mind me asking how much did it cost for you to get all your head and cylinder work done?
The point of this thread is that I dont wanna rock up to a shop and get bullshitted that I need this and that and blah blah when really all it needs is a professional clean, rehone the heads and a compression test and check for cracks.
Re: Rebuild
Posted: Tue Jan 01, 2013 9:02 am
by ZFL45H1
Daniel2019 wrote:Hey ZFL45H did you get any other part of it professionally done? Also if you dont mind me asking how much did it cost for you to get all your head and cylinder work done?
The point of this thread is that I dont wanna rock up to a shop and get bullshitted that I need this and that and blah blah when really all it needs is a professional clean, rehone the heads and a compression test and check for cracks.
All good man ask away what we r here for anyway
Cost me around 1500 I think to completely rebuild mine including all the seals and sh*t
I got block chemically cleaned came up great looks like this

and painted

Heads the same cleaned and new stem seals put in by the same mob (I think that right)


And tested for all things u have mentioned and that's it rest of the rebuild was done by dad and myself
EDIT: notice in last pic that there should be another section of the head on they won't clean that u have to just use degreaser wire brush and wipe it down will look good
And make sure u do the tappets before putting the engine in of phil069 won't be happy when u ask him to do it hahaha
Final product minus intake manifold



Re: Rebuild
Posted: Tue Jan 01, 2013 9:11 am
by Daniel2019
Cheers mate. Where did you get that done?
I might have a look at a few places around Sydney but if I cant find anything I may go to the same place as you did. I did get a quote for $780 from a place in Moorebank but he never said exactly what was included. I asked for a quote on a cylinder head reco and the reply was $780 for a pressure test and a "full service". I'm sending an email now to ask what exactly is included in the service and to see if he is able to do a proper clean etc.
Re: Rebuild
Posted: Tue Jan 01, 2013 9:23 am
by ZFL45H1
yeah double check what is include in that mate but seems right for just block work think I was quoted 699 for that
Anyway the place I got it all done at was in wyong seems dodgy if u know anything about wyong but these blokes own and race a 8sec quarter mile Porsche so they know what they r doin lol can't remember the name now I'll post that later today
Re: Rebuild
Posted: Tue Jan 01, 2013 9:24 am
by aza013
ZFL45H you went out and did all that work on the engine and cleaned it up but you forgot to clean the engine bay

.
Re: Rebuild
Posted: Tue Jan 01, 2013 9:32 am
by Daniel2019
I guess we'll find out won't we
Cheers for the info mate. And it looks really good by the way

Re: Rebuild
Posted: Tue Jan 01, 2013 9:44 am
by ZFL45H1
Lol thanks the intake manifold has been painted since then two just haven't got a photo
Re: Rebuild
Posted: Tue Jan 01, 2013 3:04 pm
by Kustom
I would get a port and polish done man if you're already pulling the engine out and planning on keeping the car!
Re: Rebuild
Posted: Tue Jan 01, 2013 7:21 pm
by Daniel2019
Kustom wrote:I would get a port and polish done man if you're already pulling the engine out and planning on keeping the car!
Yeah thats true, but again im not 100% sure on whats involved. From the little bit ive spoken to Fraz about, the intake and exhaust manifolds have to be matched, correct?
I might look into it and ask them about it when I go to get the heads and block done. Whats an approximate price for a good port and polish?
Re: Rebuild
Posted: Wed Jan 02, 2013 2:31 am
by Kustom
Have a quick read of this.
http://www.superhonda.com/forum/f93/por ... es-127827/
It's a honda forum but hey, good information.
And i'm not to sure on costs mate, ask aza if he received the receipt for his engine.
Re: Rebuild
Posted: Wed Jan 02, 2013 10:11 am
by Daniel2019
Yeah had a quick look. It would mean matching both the exhaust and intake manifolds with the heads. Because I dont exactly know what im doing I can see this becoming a PITA down the line..
We'll see haha.