My 1970 KGC10 2000 GT

ericbauer · **Posted:** Wed Jul 25, 2012 11:29 pm

Minor Update:

Kameari has come to the rescue!
Some weeks back, actually just before Bayline, I was searching for a larger than stock intake / exhaust gasket, I even experimented with making my own die and punching it out on the press but only with mixed results...

A couple people on here, as well as some co-workers, and Dave Rebello, all told me to ditch the gasket and just run with RTV only...

I gave it a try..
In fact I re-set the header 3 separate times trying to cure a exhaust leak at cyl 5, but I could never get it perfect.
The header flange checked out flat, but the leak always came from the top edge of the cyl 5 runner... that guy's not clamped very well with our header bolt arrangement...

Anyways, while it didn't show on the Kameari California distributor (Misano Motorsports), I was convinced I had seen something like a big port gasket in years past from Kameari Japan. Some phone calls later confirmed it was in fact available...

A couple weeks passed and I got a package today:

Exactly what I was after! It matched the old one I had taken off the car last month!
And not too bad at 2000JPY each - I bought several for the future...

In other news, I've been digging deeper on the Mikuni Solex that came on the car from Japan.
They are 44PHH S5 independent type carbs (not homogeneous), and so far these jet blocks have stumped a couple people...

Thought I'd post them here in case someone has seen these before?
Will (Rad2ltr) posted them on 311s.org and we got some interesting feedback from guys in Australia...

They have recessed jets like OAs, but have no bleed pipe, and no visible markings anywhere along the jet block...

Anyone?
Anyone...

Buehler?...

kev · **Posted:** Wed Jul 25, 2012 11:36 pm

Do you think those Kameari ones are oem gaskets that have been given the embiggening treatment?

And sorry, can't help you on Mikunis, I'm a Weber man myself

ericbauer · **Posted:** Thu Jul 26, 2012 5:47 am

Hey Kevin

While the construction seems similar, the paper material used looks different on the Kameari ones vs the stock ones. And the Kameari ones have the Sakura embossed stamp between cyl 5 & cyl 6 and a part number embossed between cyl 1 & cyl 2

Maybe they have a vendor make them from scratch for them

They don't look to be thicker or thinner than stock however

ericbauer · **Posted:** Fri Aug 03, 2012 8:39 pm

Hi all,

it's been a while since I posted...
And well, unfortunately, this isn't a good kind of update...

Maybe it's due to one too many over-eager demo rides for the different fans of the red car, maybe it's just due to old age...

But the red car's been running "OFF" for about a week...
I aborted a drive out to Supercar Sunday last weekend when it wouldn't rev as I got on the freeway onramp.

I swapped carbs, jets, plugs and nothing helped.

I just did a compression check and here are the results:

The plugs pictured have been in for less than 10miles and show real uneven a/f mixes, and of course the compression figures are LOW LOW LOW...

FYI STOCK L24 compression figures should be in the 170-180psi range...

It's unrealistic that I'll get it fixed in time for Monterey Historics in 2 weeks' time, so I'm out... sorry.
But like the phoenix, the red car will rise again...

"Better Faster Stronger", in the spirit of the ongoing Olympics...

wookieballa · **Posted:** Fri Aug 03, 2012 10:41 pm

damn

did you check your flow into the carbs too?

ImPo · **Posted:** Sat Aug 04, 2012 2:22 am

Sorry to hear the news Eric. Looks like you're just going to have to go with a 3.1 stroker rebuild. Although...

I've got a stock L20 laying around. A little dirty but she's got solid compression and runs well! :lol:

ericbauer · **Posted:** Sat Aug 04, 2012 7:52 am

Hey Eric

Thanks for the offer... As yours is about to be back up & running mine goes down... I'll get it sorted. No worries

Yes Kevin
Also tried both sets of carbs with same results
But at the end of the day those compression figures are way too low

Rad2Ltr · **Posted:** Sat Aug 04, 2012 9:25 am

Oh man thats not good. I'm assuming you did the compression check with the throttles wide open? You checked your valves as well? I hope you can get it sorted out without too much trouble.

Will

jncr · **Posted:** Mon Aug 06, 2012 2:46 pm

Sorry to hear about the motor.
Did you ever detune the engine once you started running it on CA gas? Remeber to take out some of the timing at a minimum and possibly re-jet when running a Japanese built engine on 91 octane.
By the numbers posted it looks like your rings are gone. Luckily rebuilding a L28 bottom end is easy and parts are cheap.
Just get it back on the road. No need to build a bullet proof, no expense spared bottom end before JCCS.

Japanese tuned L6s can be more aggressive with their fuel and timing due to the higher octane gas available.

RB26 motors need an apexi PFC and a couple clicks of the commander before they are truly CA ready.

synth19 · **Posted:** Thu Aug 09, 2012 12:08 pm

Wow, cant believe you tracked the car at night! It still looked super dark.

Nismopunch · **Posted:** Mon Aug 13, 2012 12:54 pm

Sorry to hear about the recent compression findings Eric

Unfortunately I blew my headgasket on a trip to WA a few weeks ago on the Z. No overheating but noticed coolant leaking down the side of the block..ehhh lol. Looks like we are both out for the historics coming up...nooooooooo!

ericbauer · **Posted:** Mon Aug 13, 2012 1:15 pm

you towed it back from WA?
Or you made it home just as the headgasket started to leak?

sorry to hear about it... it'll be back together before too long i'm sure

my block is at the machine shop for a hone, new rings, and a once over
my head is getting mailed out tomorrow
i dropped off a bunch of parts at the cad platers this morning
header is in the hands of jet hot

things are progressing...

i'll post pics later of some of the most recent discoveries...

-e

Nismopunch · **Posted:** Mon Aug 13, 2012 1:31 pm

I made it back thankfully ok with a stressed out eye on the temp gauge haha. Glad to hear you have already begun the rebuild process, and im sure once that monster is freshly rebuilt you ill be VERY happy. Keep us updated!

Luke

ericbauer · **Posted:** Sat Aug 18, 2012 8:51 am

UPDATE:

Pulled the engine last week and disassembled it... I was in for a series of very pleasant surprises which only served to reinforce the very good gut feeling I've had about this car ever since pictures were first emailed to me by JDML back in October 2011...

Interestingly the oil pan was safety wired - that's odd... but it had apparently sprung an oil pan leak on the driver side at the pan seal and rather than undo the safety wires, the previous owner had schmegged on a bunch of black silicone sealant - that's odd too...

Pulled the oil pan and this is the first thing I saw... wow! That rod cap looks VERY PROMISING...

Pulled the rod cap out for a closer look... WOW again!

Pulled the pistons... :shock:

Someone went to town on these rods... I measured center to center and it came out to 133mm, so I guess they are L24 rods
:shock:

Finally stopped looking at the piston / rod combo, and instead checked out the crank... V07 is the holy grail - this is the Nissan Maxima LD28 diesel crank!... I've always wanted one of these...

Now on to the pistons in greater detail. These pistons are cast, not forged. They look a lot like the Kameari 3.1L pistons, as pictured right here:

http://kameariusa.com/L6_L31_Street_PK_withL20rods.php

But I'm pretty sure the Kameari USA website has a typo, it lists the wrist pin height at 35.5mm, not 33.5mmm...

On Brian's ZCC JDM page, they have the correct pin height:
http://www.zccjdm.com/catalog.php/azcarbum/dt43033/pd858315/_L6__3.1_LITER_STREET_PISTON_KITS_L20_LD28_

The Kameari pistons are listed as supposed to be used with L20 rods... Not L24.
L20A rods are 128mm long
L20B rods are 145mm and don't work with our L6s

If you do the compression ratio math, you'll see that something's not quite right...

That looks like the Nissan "bowtie" to me...

"ui" with a ring around it - maybe this is the foundry that casts them for kameari? if these are in fact kameari pistons?

the pistons were individually relieved to attain exactly the same weight:

If it is "RH Factory" in Nagoya that built this engine, then they really went to extraordinary lengths and this matches what I've been able to gather about their reputation from different online sources... The big bummer though is that it seems like they are no longer in business... Maybe they were a recent casualty of the economic crisis? Next time I'm in Japan, I'll go through Nagoya and look up their old address just to see if I can find out any additional info...

So to summarize, the red car is actually not a 3.0L L28... It's a 3.1L L28!!

Having measured everything, the specs are as follows:

L28 N42 block
89mm bore
88.3mm piston diameter
Supposing the pistons are Kameari units, their listed valve relief volume is 2.7cc
33.5mm measured pin height
21mm x 58mm measured wrist pin
133mm measured center to center (L24) rods
83mm crank (LD28 V07)
90.5mm bore & 1.2mm thick headgasket

Supposing a stock combustion chamber volume of 44.6cc for my N42 head, that puts compression ratio at 10.5:1
The head is going to get cc'ed this week and flow bench'ed just so I will have a better idea of what exactly I've ended up with.

I did not find any broken or melted bits, that seems to confirm the leakdown test which indicated it was JUST the rings that gave up ...

kev · **Posted:** Sat Aug 18, 2012 6:48 pm

Stroker! Nice find, Eric

BTW, what pickup tube you got? Is it the L20 one?

ericbauer · **Posted:** Tue Aug 21, 2012 5:50 am

Kevin,

Picture of oil pick up tube for you:

-e

ericbauer · **Posted:** Wed Aug 22, 2012 11:08 am

Need to revise the math above, because I just got some new info...

The head was cc'ed last night...
A stock N42 head is 44.6cc

My N42 head is actually 37cc

So the red car's compression (when new) was actually 12.1:1 !!

uras1 · **Posted:** Thu Aug 23, 2012 3:57 am

nice find, what kind or rebuild will you do. im guessing just rings and bearings?

Nismopunch · **Posted:** Sat Aug 25, 2012 12:18 pm

That's some monster of a find! Even more of a beast than previously thought haha. Hope the rebuild goes well and you are back on the road soon :tu:

Super X · **Posted:** Mon Aug 27, 2012 8:43 am

ericbauer wrote:

So to summarize, the red car is actually not a 3.0L L28... It's a 3.1L L28!!

Having measured everything, the specs are as follows:

L28 N42 block
89mm bore
88.3mm piston diameter
Supposing the pistons are Kameari units, their listed valve relief volume is 2.7cc
33.5mm measured pin height
21mm x 58mm measured wrist pin
133mm measured center to center (L24) rods
83mm crank (LD28 V07)
90.5mm bore & 1.2mm thick headgasket

Supposing a stock combustion chamber volume of 44.6cc for my N42 head, that puts compression ratio at 10.5:1
The head is going to get cc'ed this week and flow bench'ed just so I will have a better idea of what exactly I've ended up with.

Eric, Thanks for sharing the pics of your block. Your block is pretty common with what I’ve seen in 3.0-3.1 in JP. The pistons are a oem Nissan. Kameari, Speed Shop Kubo and just about every major L series speed shop in JP literally get them from the dealer. They are very good/strong and believe it or not they are what’s used in 320+whp L6 engines.

There are several different versions of this piston from Nissan that can be used but only specific type is used by the big hp shops in JP (for modification reasons). Depending the speed shop they will take the factory piston cut in valve reliefs (usually 2.5mm-3mm), modify the skirts and lighten/balance; That's it. You can grab a set of new cast pistons w/ rings on ebay for around $154 and have the work done by a local machine shop for probably around $50 a piston. It amazes me that some people are willing to pay the $1500 premium for the same thing just because it came from a shop in JP. :roll:

The real mystery and the uniqueness of each high hp 3.0-3.1 L6 lies within the head. This is the difference maker and im pretty sure you probably realized this since your tear down. I understand if you wouldn't want to get into specifics on even show pictures on your head setup, but I am a bit curious as to what work was done on your N42 as far as porting/shaping, valve sizes and most importantly cam choice. I wouldn't be surprised if you have a Kameari 77i or even better a Wako 75S cam :shock:

Mario

My 1970 KGC10 2000 GT

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