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Uncle Festa
23rd May 2013, 11:54 AM
Morning fellas (and gals if any), Preparing a 4.8 to go into a GQ. I need- manual bellhousing, coil packs, starter, alternator, engine mounts, general engine bolts, and other engine parts for a TB48E. Also looking for LPG ECU and converter/regulator for injected gas. If anyone has or knows someone who has, contacts or info much appreciated.
Wondering whether anyone knows if a manual bell housing from a GQ TB42E will fit onto a TB48E block. According to a guy at 'Marks Adaptors' they use all the same adaptor for conversions throughout the Nissan range including the 4.8. So based on that the GQ bell housing should fit maybe less/more a bolt or 2. I have had a look and measure on my GQ and my recently acquired TB48E, and measurements are different between bolts. Also need to know if flywheels and starters are same.
Thanks

threedogs
23rd May 2013, 01:11 PM
Why not just turbo the 4.2 I know of a few pulling 14.5sec 1/4 mile times, 235 RWKw.But..............
they are not daily drivers, Simon from 4WD TV fame has a turbo on his 4.8 I think as his daily ride
Matt would be your go to man here ,

taslucas
23rd May 2013, 02:18 PM
Why not just turbo the 4.2 I know of a few pulling 14.5sec 1/4 mile times, 235 RWKw.But..............
they are not daily drivers, Simon from 4WD TV fame has a turbo on his 4.8 I think as his daily ride
Matt would be your go to man here ,

Have a look in members rides for bigrigs GQ. Thread called Tank-big grey and ugly. He turbo'd his TB4.2 and its set up more for a daily.

Uncle Festa
23rd May 2013, 02:58 PM
Have thought a lot about what I prefer. Considered going down the turbo path. But no gain in economy. But fitting a GQ with the far more efficient and powerfull (50% more power & a lot more torque) TB48E and weighing 400 to 500 kilos less than a GU, the improvement overall has to be very considerable. And a relative hassle free conversion compared to anything else.

Uncle Festa
6th January 2015, 11:27 PM
Well it has been some time and after a lot of consideration, I decided given the cost of rebuilding the 4.8, to take yr advice three dogs and fitted a kaniguwa turbo. Results/prerformance is beyond my expectations. Huge increase in torque and therefore drivability is just what the doctor ordered. Economy is similar if I drive like a Grandfather but that is a bit hard to do now so its perhaps a little bit worse. Have just gone to bigger tyres so all things now considered economy is on par.

Problem I now have is the clutch is slipping and have just ordered new clutch with clamp load of 1100kg which may give me a rather hard clutch pedal given a standard 4.2 GQ pressure plate clamp load is apparently approx. 700kg. So I am wondering whether I should have considered going for the larger clutch for a 4.8 which is 300mm rather than the 275mm clutch and could therefore have gone with say a 900kg clamp load which will mean the pedal won't be too hard. I have a bad ankle/foot and don't want to suffer. So I am wondering does anyone know if a 300mm clutch and pressure plate will fit my GQ TB42E flywheel. Or do I have to get a TB48 bell housing and flywheel and will this fit up to my TB42E and do I need a different/TB48 starter etc? Other options may be using the GU/TB48 vacuum clutch booster which may be bigger than the GQ/TB42E, but I don't know if there is any difference? Also wondering if master and slave cylinders are different/bigger for the GU/Tb48?

Any help mmuch appreciated, Thanks

threedogs
7th January 2015, 08:43 AM
isn't the pedal a hydraulic affair, meaning it wont matter what clamp pressure clutch you put in,
Always thought that turboing a big petrol was cost effective with a great results, Power to burn

Thanks for the up date too, most dont follow up

jff45
7th January 2015, 10:24 AM
Why not put some pics up of your turbo build?

Uncle Festa
23rd September 2016, 09:11 PM
Why not put some pics up of your turbo build?

OK. Only have a couple of picks of Turbo bolted to Chinese made Stainless steel Manifold. 6915469155
Have since thrown this manifold in with the scrap. It was badly distorted before I fitted it, both the face to head and also face to Turbo. Even though I shaved it on the mill, it couldn't cope with the heat and had too much trouble with it leaking. Ended up fitting a cast iron DTS manifold and even though it was $530, I now have no issues with any leaking. Having said all this about the Chinese manifold, and I wouldn't recommend anyone buy and fit one, part of the heat (too much) was I hadn't upgraded my exhaust to an unrestricted type. If I had done this before changing manifolds, I may have been able to retain the Stainless manifold, but I doubt it. Stainless steel doesn't conduct and cope with heat anywhere near as well as cast iron. The stainless manifold definitely had a lower engagement (1200rpm approx) due to smooth finish internally, compared to the Cast Iron which is 1600rpm. This is good and bad both ways, but Stainless/1200rpm was a bit too touchy for my liking, but I will say the economy seemed better. Best economy I can get with Cast Iron manifold is 400ks per 90 litres LPG. Stainless I could get 425ks per 90 litres LPG. Mind you this is trying hard/not sticking the boot in, only when some slow fart gets the better of me.

So at the end of the day if anyone wants to turbo their TB42E, I highly recommend it!
If I did it again, I would consider either making my own manifold from steam pipe or buying one from the guy who I think is in New Zealand and advertises on Ebay. Kinugawa Turbo I am very happy with also on ebay, but need to get the right model Turbo to suit TB42E. Was just looking for invoice and also looking on ebay to see if I can find model/type I used, but can't be sure. If anyone wants to know, I am sure i can find it, or email Kinugawa and ask which one they suggest. DTS manifold is a low mount rather than high mount stainless (as per photo).

Only issue I have now is engine mounts, which I am planning to check tomorrow. Have already replaced one a while ago, and I am pretty sure one or both has failed again. Just can't cope with the torque, so going to see if i can fit some TB48E mounts as they should handle the increased torque.

Although I don't visit this forum often, might add some more pics next time I am on. Happy to answer any questions, but might have to be patient for an answers

Cheers

MudRunnerTD
23rd September 2016, 09:53 PM
Nice one cheers mate. I had missed your thread completely. I have a good mate that did a TB48E conversion into his TD42T GQ. He loved it! Went like stink! No comparison, no looking back at his TD either!!

He loved it so much he bought a GU TB48 and his GQ TB48 is for sale now. Just wanted the comfort of the GU. The motor is wicked.

GQtbpower
17th June 2020, 08:12 AM
I'm thinking about going down the path of tb48 into my manual GQ, would like to know if I get an engine with loom and ecu what else do I need to install it, like engine mounts etc.

Appreciate your suggestions