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csa's engine rebuild


csa

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okay

 

The next engine has been taken apart and it looks much better. 4 rod bearings are gone but the mainbearings are ok, only one of them has some slight marks.

Pics will be posted tomorrow.

 

A couple of questions:

 

1. what kind of tool do you normally use for the ARP head studs? (a normal size "top" wont fit it, so my builder had to cut down he's expensive tools.

2. how much torque should we use when tightening the ARP head studs? specfications says 34NM plus 2x90degrees, but is it the same with ARP bolts, and could it be translated into all NM ?

 

thanks guys :-)

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okay

 

The next engine has been taken apart and it looks much better. 4 rod bearings are gone but the mainbearings are ok, only one of them has some slight marks.

Pics will be posted tomorrow.

 

A couple of questions:

 

1. what kind of tool do you normally use for the ARP head studs? (a normal size "top" wont fit it, so my builder had to cut down he's expensive tools.

2. how much torque should we use when tightening the ARP head studs? specfications says 34NM plus 2x90degrees, but is it the same with ARP bolts, and could it be translated into all NM ?

 

thanks guys :-)

 

yep ground down socket is the way forward and mine are done up to 70ft/lbs, not sure what that is in Euro land but i'm sure you can get the conversion, oh and forget about all that 90 degree stuff thats for stock torque to yield bolts

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time for an update:

 

this s how the bearings looks like, some of them even seems to have the original coating on then...is that normal:

 

http://img13.imageshack.us/img13/9561/christanssupra063ji8.jpg

 

http://img4.imageshack.us/img4/1807/christanssupra064qn4.jpg

 

http://img10.imageshack.us/img10/3964/christanssupra065xz3.jpg

 

http://img134.imageshack.us/img134/4271/christanssupra066ix6.jpg

 

also the machine shop said that the crank was fine and it only needed a polish.

Btw whats you oppinion on honing...best done by hand or machine?

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Hiya bud.

 

I wouldn't personally try hand hone a crank pin that small.

Can't see original coating in the pics. They may have come with a protective wax coat which would be obvious.

 

That first set of old bearings from the bottom looks like the white metal actually got hot enough to come out the side. :blink: Not nice.

 

Anyway. Good thread cheers. Luck for the rest of the build.

 

A

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Some are knackered, some are not. As I said, bin the rods and buy new, get the block main bearing bores checked for size, roundness, taper and straightness. Any issues there use another block. There'll be shrapnel in the oil galleries, the block needs all the oilway plugs out, steaming, rifle brushing, steaming again, then hot air drying. Or it'll fail again. Bin any oil coolers and wash and blow out all oil hoses properly. It's a lot of work re prepping a blown up engine.

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All of above has been "ordered" with the machine shop. also we discovered that the old crank had some ovalty in the 3rd. it can be measured in hundreds so another cranck will be used. The new one comes from a sound engine (gone stroker), but will be balanced and checked ofcourse.

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time for an update:

 

As expected the head from Jamies old engine contained nothing but stock stuff. no ferrera springs or retainers, so we guess that turbofit must have switched head at some point when they fitted the new shortblock.

BUT that's all in the past and and this week the head has been completely disassembled for cleaning. all springs have been measured and they are within tolerences. ports have been polised a bit and it will be sent of for machining next week.

 

a few pics:

 

http://img17.imageshack.us/img17/4606/christanssupra016qe0.jpg

 

http://img403.imageshack.us/img403/1150/christanssupra017oy9.jpg

 

a few pics of the polishing work:

http://img17.imageshack.us/img17/1320/christanssupra007jc0.jpg

 

http://img403.imageshack.us/img403/931/christanssupra042uc4.jpg

 

http://img403.imageshack.us/img403/435/christanssupra054fm3.jpg

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Where are all the bottom spring seats? I am only asking in case they were left out previously, which will *ugger the head and reduce spring seat tension. They tend to adhere to the head with the oil surface tension.

 

BTW if an alloy OHC or DOHC head warps it's usually scrap, you can machine the head's block face true, but virtually every time the cam journals are no longer in line, but banana shaped, as the whole head casting warps, which can cause cam seizure, excess wear and low oil pressure. You can line bore the cam journals but the cost to do it properly will exceed that of a new head.

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well they head will ce fully mesured up before we do anything. but it seems that it only needs a very light polish on the surface to clean it up

 

btw Chris, did you get my pm regarding the oilcooler?

 

oh, and the bottom spring seats sits in 2 stacks in the bottom of the pic

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gawd :taped:, i hope you didn't pay alot for that "head work" there apears nothing more done than grind off all the lovely casting Mr T put in there for a very good reason, they haven't even knife edged the centre port wall and managed to nic the valve guides which in itself is not the end of the world but is not really indicative of quality work :blink:

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Here's some pics of what i did with my head... DIY

 

Its not proper polishing, ide call it cleaning, and i certainlly didnt grind a bit off my guides! That looks a nasty job, sorry :(

 

http://i77.photobucket.com/albums/j75/DannoSupra/Photo173.jpg

 

http://i77.photobucket.com/albums/j75/DannoSupra/Photo171.jpg

 

http://i77.photobucket.com/albums/j75/DannoSupra/Photo169.jpg

 

(i have got better pics somewere)

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well it's not complete yet, and the guy doing it is not charging me for it. as DannoSupra says, it's merely cleaning with a bit of polish.

 

unless you really know what your doing step away from the grinder now, the intake ports are deliberately the surface finish they are for very good reasons its not a case of Mr T being lazy, the rough surface finish actually promotes better flow, it also helps drops of fuel that hit it evaporate and there are also boundary layer effects as well (think of a sharks skin or the dimples on a golf ball), making the port bigger will hurt air velocity which may give you 1 bhp at 7000rpm but loose you 10bhp from the mid range, its a complex subject and Mr T has done a pretty damm good job, on the flip side buff away to your hearts content at the exhaust ports as the smooth finish will deter carbon build up

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Next, I've had a little work done to the GReddy inlet manifold. Before, it was powder coated, but this has been removed now (with great difficulty), and reveiled a nasty rugged surface underneath:

 

http://img147.imageshack.us/img147/5856/christanssupra020.jpg

 

also the corners of the casting didn't look too good:

 

http://img520.imageshack.us/img520/7329/christanssupra001.jpg

 

This is how it looks after intensive machining work:

 

http://img27.imageshack.us/img27/7359/christanssupra013.jpg

 

wash down in Sal Ammoniac after polishing:

 

http://img407.imageshack.us/img407/626/christanssupra026.jpg

 

finished result after approx 14hrs work (courtesy of my main man Kennet):

 

http://img407.imageshack.us/img407/4536/christanssupra038.jpg

Edited by csa (see edit history)
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