Patrol 4x4 - Nissan Patrol Forum banner

221 - 237 of 237 Posts

·
Registered
Nissan
Joined
·
1 Posts
Hi folks,

I am new here and will shortly be the owner of a 94 GQ non turbo 4.2. I have little mechanical knowledge. I have bough this vehicle as I have heard that with 270k on the clock with this engine it still has a decent bit of life left yet (assuming its been serviced and mainatined etc.) So after reading all of this and much of it going over my head do I have the stronger or weaker motor....and if I turbo it what boost should I run, I want no strain on the motor at all, I would rather longevity than extra power. In the past if Have a 1999 LC Toyota ute with the 1HZ and I imagine this patrol and that vehicle are similar power wise when not turboed.


Kind regards Paul.
 

·
Registered
nissan patrol
Joined
·
34 Posts
td42 5/96 black top oil pump on timing gear 28mm pins

Hi guys here is some info from my 1996 6 month gq with a 5/96 td42 blacktop oil pump on timing gear pistons are 28mm pins piston crown is 15mm thick piston top with pin and clips is 1.070 kg with no rings on no valve relief cuts in top of piston also has the turbo casting on the block
 

·
Registered
nissan
Joined
·
416 Posts
best for turboing:
GU turbo black top, has the turbo oil drain cast into the block. 28mm gudgeons, different bolt pattern on the back of the crank. Vacuum pump driving off timing gear below fuel pump.
Good for 900+ Nm if you build them properly with ceramic bits etc. EG: One Wild Diesel in Perth build by United Fuel injection and Zac. Shawn Swaffield's various vehicles over east.
precombustion chamber ports are larger. Compression ratio 22.5:1
Engine number starts with TD42Tnnnnn

second best:
Silver top (which dont all have silver rocker covers) Build date to somewhere around August 1995. Vacuum pump on back of alternator. Good for 650-700 Nm at 30 psi in short bursts if you watch your gauges with standard internals. 30mm gudgeons. "small/standard" back end on crankshaft. small precombustion chamber ports. Compression ratio 22.7:1. I've just blown one of these up being an idiot and the block and liners have disintegrated between #3 and #4. I'd keep it to under 650Nm with these. Engine number starts with TD42nnnnn

Good for mild boost only:
non turbo GQ and GU "black tops" built post august 1995 approx. Vac pump driven off timing gear below fuel pump. No turbo drain cast into block, "small/standard" back end on crankshaft. 28mm gudgeons.
12 psi non intercooled, 15psi intercooled, Thou Shalt Not Pass this boost level. reasonably lively engine due to the lower mass pistons, especially if you use 4.375 diffs. small precomb chamber ports. compression ratio 22.7:1
the pick of the bunch for moderate applications because everyone wants the "strong" ones and the lower reciprocating mass helps performance.


Unknown:
Factory turbo Y60 Safari (GQ safari import)


From the first page, i assume you have read this but this is what it is based of. This is what deccers is referring to
You got the gudgeon pin diameters around the wrong way mate. Factory turbo (td42t) is 30mm and silver top is 28mm.
 

·
Registered
nissan patrol
Joined
·
34 Posts
hey mate no i dont its pulled apart in the shed and thats what it is. Also that is wrong as 30mm in the NA black tops have the lighter pistons.Does any one have some weights on the pistons and pins and clips no rings on from silver top engines ?
 

·
Registered
nissan
Joined
·
416 Posts
hey mate no i dont its pulled apart in the shed and thats what it is. Also that is wrong as 30mm in the NA black tops have the lighter pistons.Does any one have some weights on the pistons and pins and clips no rings on from silver top engines ?
Gu factory turbo has 30mm gudgeon pins and the early silver tops have 28mm.Yes some silver tops actually had black rocker covers. These are facts.
There were apparently also(i have not seen but heard of on several occasions) some bitsa changeover motors built where they used a random mix of parts. Sounds like yours is either non original or one of these random bitsa engines.
 

·
SUI GENERIS UTE
GQ Ute 1990 Silvertop
Joined
·
5,940 Posts
That would explain the 28 pin and flat tops and its weight. I never knew.
 

·
SUI GENERIS UTE
GQ Ute 1990 Silvertop
Joined
·
5,940 Posts
Love to see that mate.

Eventually we will get this thread right and accurate. When i am happy we are close to correct i will edit the thread to remove the miss info.
 

·
Registered
nissan patrol
Joined
·
34 Posts
piston from 5/96 black top

here is the piston from the 5/96 black top engine number TD42-121142
oil pump on timing gear
cam followers 26mm
piston gudgeon pin 28mm
piston and gudgeon pin with clips no rings on weight 1.070kg
crown thickness 15mm
turbo oil drain and feed casting in the block
Z2 stamp on crown






 

·
Registered
nissan patrol
Joined
·
34 Posts
yes that is why i would like to see some weights on the pistons from a few guys on. here but the silver tops had the valve reliefs in tho top I dont know how much amount of materiel is cut of that could be the reason for being lighter but still has the thicknes around the edges. im not sure
 

·
Registered
Joined
·
4 Posts
best for turboing:
GU turbo black top, has the turbo oil drain cast into the block. 28mm gudgeons, different bolt pattern on the back of the crank. Vacuum pump driving off timing gear below fuel pump.
Good for 900+ Nm if you build them properly with ceramic bits etc. EG: One Wild Diesel in Perth build by United Fuel injection and Zac. Shawn Swaffield's various vehicles over east.
precombustion chamber ports are larger. Compression ratio 22.5:1
Engine number starts with TD42Tnnnnn

second best:
Silver top (which dont all have silver rocker covers) Build date to somewhere around August 1995. Vacuum pump on back of alternator. Good for 650-700 Nm at 30 psi in short bursts if you watch your gauges with standard internals. 30mm gudgeons. "small/standard" back end on crankshaft. small precombustion chamber ports. Compression ratio 22.7:1. I've just blown one of these up being an idiot and the block and liners have disintegrated between #3 and #4. I'd keep it to under 650Nm with these. Engine number starts with TD42nnnnn

Good for mild boost only:
non turbo GQ and GU "black tops" built post august 1995 approx. Vac pump driven off timing gear below fuel pump. No turbo drain cast into block, "small/standard" back end on crankshaft. 28mm gudgeons.
12 psi non intercooled, 15psi intercooled, Thou Shalt Not Pass this boost level. reasonably lively engine due to the lower mass pistons, especially if you use 4.375 diffs. small precomb chamber ports. compression ratio 22.7:1
the pick of the bunch for moderate applications because everyone wants the "strong" ones and the lower reciprocating mass helps performance.

Unknown:
Factory turbo Y60 Safari (GQ safari import)


ALL TD42s SHOULD LAST FOR AT LEAST 600,000KM WITH A TURBO AT MODERATE POWER LEVELS WITH REGULAR SERVICING.
Sorry to be a pain, going to look at a GQ very soon and want to see what engine it has.
Are you saying that any td42 built before August 1995 is a silvertop?
Cheers
And sorry I don't know how to only quote a small section.
 

·
SUI GENERIS UTE
GQ Ute 1990 Silvertop
Joined
·
5,940 Posts
8/87 to 7/95 is the silvertop with different camshaft and 25mm cam followers. 8/95 to 5/96 is a blacktop with 28mm gudgon pin and a heavier piston than the silvertop by 110 grams but has 26mm cam followers and the same camshaft as all the later TD engines including the T engine. All other N/A black top pistons except T engines have a very light piston which is some 80 grams lighter than the silvertop piston. This very light piston in the after 5/96 N/A engine doesn't help when you are going to turbocharge this engine. Its not really about the piston weight is about these pistons dont have oil galleries in the piston crown for cooling like the T engine has.
 

·
Premium Member
Joined
·
511 Posts
Thanks for clearing that all up pete my bro outlaw is looking for a wagon and I said pre 94 or post 99 with t motor so was safe by a couple 👍
 
221 - 237 of 237 Posts
Top