Nelsonmxmarc 1993 GTSt Type-M Build / Tips-tricks for HCR32 (Skyleezy!)

[frankiman]

Right, they vinyl wrapped last year or the previous years cup car with a dimpled vinyl wrap and it seemed to cut down lap times. That's disputible though, but at any rate, my point on extrude honing kind of outlines the reason for going to a perfectly smooth finish. There are arguments in either direction..

We've met?? Oh right through motocross right? Absolutely, pass by anytime!

http://www.autoblog.com/2009/10/22/mythbusters-golf-ball-like-dimpling-mpg/

[nelsonmxmarc]

So all bearings are in tolerance/good shape.. SO, my only thoughts can be that gearset slop, and the rather steep gear cuts is what makes the noise at idle in neutral. Since theres no noise driving, and no noise difference between 3rd/4th (direct drive), i have to assume its just the way the gearset is designed.. Kind of a bummer but oh well!

Going to use my spare gearset with Redline heavy duty and see how the noise goes this summer, if not,i can easily swap bellhousings.

[nelsonmxmarc]

Minus the ARP headstuds which are going to be sorted out monday, hopefully, these are all my new goodies, including new carbon fibre doodads (minus the carbon firewall and speaker deck cover)





Now to install..

[amnash]

is that how your pistons looked when you took your engine apart? when i took mine apart the tops of them were super black and rough...
how should a piston look when you remove it?

[nelsonmxmarc]

is that how your pistons looked when you took your engine apart? when i took mine apart the tops of them were super black and rough...
how should a piston look when you remove it?

They should look as you described. I cleaned mine with a brass wire brush to rid of the carbon build up. I'll shot a pick of the pistons i pulled from my other block. You'll get a good idea of what to look for.

They shouldnt be TOO dirty, though. You dont want them to have tons of build up, and also keep an eye out for detonation marks. Another common issue are small cracks around the ring land. Look carefully, sometimes they're very very small.

My other block shows considerable blow by.. You'll see marks of combustion past both rings (normal) but also past the oil ring (not normal), making a swooping pattern such as this;



This is pretty normal;



You can see theres combustion/carbon between both seals, that's fine. Its the oil seal that should be retaining blowby.

Also make sure your piston end gaps are in the correct location when reinstalling..

I looked at my oil seal when it came out - there are 2 rings sandwiching an inner retainer, both were in the incorrect location. They're about 45 degree apart (top vs. bottom) and the two top rings are 180 degrees apart;

[amnash]

yeah, i didnt have any carbon build up past the rings so thats good. but when i took the rod bolts out my piston just dropped out... so im thinking i had alot of blowby? and alot of lost power?

[nelsonmxmarc]

By out, do you mean you released the conrod nuts and the piston simply dropped through? Due to the rod bolt deformation, the conrod carrier doesn't usually just separate like that. You normally have to take the bolts out with a small mallet. Once theyre free of the carrier, you'd need to force them out the other side. Normally the first 2 rings slide out with a bit of force, and the oil ring takes a bit more. If the piston slides right out, it could either be due to temperature (VERY COLD), or the rings out of spec.

Look in the FSM, there is a way to check ring tolerance to see if it's within spec. You'll also need to check with a telescopic gauge, the cylinder bore diameter. OEM is 78mm, there is a run out tolerance and an oval tolerance that will need to be checked with an inside-diameter micrometer as well.

Also, check the piston run out with an outside-diameter micrometer; tolerances are available in the FSM for this as well!

... then of course the crank journal run out, conrod bearing tolerances and with a plastigauge or feelergauge, the crank/conrod spacings

[nelsonmxmarc]

One thing i've learned from experience;

When you reinstall the conrod bearing carrier to the crank journal, oil ONLY the journal face, and not the bearing race that touches the carrier. If you do, the bearing will not seat properly on start up (floating on a small surface of oil) and will score the bearings.

[cschepp]

Sounds like your doing a good job... Keep it up man.

Hey if I take a stroll down to Montreal this year, you up for a cruise?

[nelsonmxmarc]

Sounds like your doing a good job... Keep it up man.

Hey if I take a stroll down to Montreal this year, you up for a cruise?

Absolutely! Always down to meet some fellow members and go for a ride!

[cschepp]

Excellent I look forward to it. I'll figure out when I'm going to go down and let you know. I'm going to try for first week of july

[nelsonmxmarc]

Small update..

Decided to repaint the engine bay anyways. I'm very anal about small scrapes/discolouration's and etc so this had to get done..

Also mounted my GTR intercooler and cut the hole on the driver side to fit the piping/oil cooler lines.

And then i finally mounted my new suspension. Front is done.. Cleaned the wheel wells up too.. Turning out to be more of a showcar than a track car lol

[jessem]

Ive wanted to do that to my rebar but im worried if someone leaned against the corner of my bumper it will cave in easy.

[nelsonmxmarc]

Yea... i would never let anyone lean against my car.. lol :P Plus, being the edges are convex, they're quite resistant to flex, like an egg. So i wouldnt be too concerned about that.. I'd be more concerned about the outcome of the guy leaning on my car... Ugh.. zippers, buttons.. Paints worst nightmare

[bellis_GTR]

Wooooow, why didn't you tell me you put that Monster on the front? I see what you mean now by cutting the re bar. How much weight did it save? Did you do the rear as well?

The suspension looks tighttttt.