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N/A To Turbo - Very Detailed

Started by NiceTints · 2 Nov 2011 · 7 replies

Preserved from CalaisTurbo. Original authors and dates are shown; archived members are not current Holdcom accounts. View original archive ↗

NiceTintsArchived member
Hey guys, I realise there is already a thread at the top of the Non-Turbo page about n/a to vlt, But its pretty brief and just list's parts from what I can read. I've gathered a heap of info over the past week or two and have come up with a detailed parts list and overview of what is needed for a conversion, I tried my best to get all the info I could. Moderators Please Make This A Sticky, Please. Ok so here it is: N/A Highcomp Turbo Setup To do it yourself you will need the following: - Exhaust manifold from turbo engine (get one from a wrecked VL turbo or have one made up) - Turbo itself (Garrett T03 was a stock unit, accept this as a minimum) - Turbo injectors (around $98 from your local spare parts store or wreckers) - VL Turbo ECU - you NEED this to run the turbo injectors, they use a different pulse width to the NA engine injectors - Intake pipes - from turbo to intake manifold, stories circulate how the NA plastic ones tend to explode under boost, metal ones are needed - Dump pipe from turbo to catalytic converter (you'll probably want a bigger exhaust system as well) - Exhaust manifold gasket and turbo to dump pipe gaskets - Oil and water lines to run to turbo, these are essential to your new turbo to prevent it exploding! - Knock sensor: detonation can be a problem if there is too much boost or not enough octane in the fuel. This wires up to the VL turbo engine computer (OPTIONAL)
 - Blow off valve
 - Intercooler
 - Turbo engine oil pump (there bigger turbo motor’s) If you're building an RB30ET and use a VL series 1 engine block, you need to put a T-piece in the oil pressure sender hole in the block and use one of those for the turbo oil feed line. Important! This should ONLY be done after you have upgraded your brakes to turbo spec! N/A brakes and a Turbo DO NOT MIX, they could choose to FAIL at the worse possible time. This is for everyone's safety not just your own. Original Turbo and Non Turbo Differences Engine:
 There are a few differences between a Turbo engine and a Non Turbo engine from factory
 Cam
, Oil Pump
 & Pistons. Non-Engine Parts - Brakes on the VL TURBO are larger, and they have got finned calipers
 - Rear brakes are always DISK on a VL Turbo
Diff on a VL turbo is 28 spline Vs. 25 spline for non turbo (28 is MUCH stronger)
 - Master Cylinder (brake) is 1″ instead of 15/16′ths
 - Brake Booster is Double Diaphragm in a turbo car
 - VL turbo Manual is stronger MX7 vs. MF5 (non turbo is useless)
 - VL TURBO auto is stronger and has an oil cooler Brakes: If you obey the speed limits your brakes won't fail (from normal driving). It's when you start to increase the boost and reach higher speeds that the standard brakes hold their heat just that little bit longer, and reach a less effective state sooner. Having said that, it's advisable to have them serviced thoroughly as a bare minimum, if not upgraded. i.e. Machined rotors, New pads, Better brake fluid etc. Tires: A decent set of tires is advised when adding a turbo, Safety shouldn't be budgeted for as part of the conversion. Brakes are only as good as the tires. Don't be stingy and get retreads either, or only buy for the rear. All 4 wheels should have new tread on them. Original Turbo and Non Turbo Differences Engine: There are a few differences between a Turbo engine and a Non Turbo engine from factory 
Cam
Oil Pump
Pistons Engine Block:
 The Turbo aka series 2 engine block has got the fittings as bolts in the last picture of this post.

 Identification of a Factory Turbo engine block: a8 designates rb30et, a6 designates rb30e. It will only be on the number at the RIGHT HAND FRONG of the motor, the number at the left hand rear will always end in A. Turbo: The Turbo Used is a Nissan Garrett T3, which is water-cooled; it has an internal Wastegate, which is set to approx. 6 PSI. Safe boost past this level is around 12-14psi, with a front mount intercooler and 3" turbo back exhaust. Compression: The ETs run 7.8:1, Es run 9.0:1. Turbo motors generally have lower compression than their naturally aspirated counterparts to deter knocking. There is a chance of detonation (and not detonation as in "blow up", like i've mentioned a few times) is increased on an NA conversion motor. Fuel: Fuel maps released on the standard ET ECUs were written on standard RON91 fuel, which what was available in '86-88'. When you move onto an aftermarket ECU (e.g. Haltech, Vipec etc) and get tunes performed on a dyno, then you should discuss fuel with your tuner and have it tuned accordingly. Having said that, if you can afford the premium stuff it is preferable, if not 95 octane should be considered as a minimum, which would be fine. Fuel Pump: N/A Fuel Pump Is fine to use with the conversion. Camshaft: The Turbo camshaft has got less overlap than the non-turbo one both are useable. Knock Sensor: When it detects pinging, it will retard the timing 5 degrees, if you are running a turbo computer there is a guide on installing one somewhere on calaisturbo. Oil Pump: 
N/A Oil Pump Is fine to use with the conversion. Fuel Regulator:
 N/A Fuel regulator can be used with the conversion (Not With Turbo Plenum). Fuel Rail: 
N/A Fuel Rail Can Be used with VLT injectors (Only With N/A Plenum). Plenum: N/A Plenum can be used with the conversion (Flows Better Too). Automatic Transmission: 
N/A Auto Transmission is hit & miss, highly recommend the first to do list is to get it bulit stronger or Aid it with Transmission Cooler that may increase its life some what, as costs to buy/replace one would reach around $300-400 professionally done. Manual Transmission/ Clutch: 
The MF5 is a very weak box (I broke 2 with a very stock N/A) they won’t handle too much, if you drive like a granny, it should last 6 months or so, there are less syncros in an MF5 which could can lead to some damage when changing gears hard ("slamming" in into gear); however gentle shifting can see an MF5 hold power (reportedly) up until around 220rwkw, where you can start to see teeth being warped and pushed off the gears. Same for the RB20DET boxes, however they have dual syncros and are generally better option when on a budget. There are differences in the clutch; i.e. MX7 - 10", MF5 - 9.5". The MF5 clutch is preferable as it is the same diameter as the Skyline series, and therefore gives a much wider variety of off the shelf performance clutch options. e.g. Exedy Heavy Duty clutch kits. etc Exhaust Manifold: The Standard Holden Manifold can used, be sure to check if it is cracked, also it would be a good idea if you replace the studs, by spraying with WD40 or similar. Turbo Dump Pipe
: The Holden one is fine; you can get a larger one. Dump to Cat pipe
: The standard one is used, although you can get a larger one made up. Crossover Pipe: 
 It has got one fitting on the side, which is a Vacuum hose that goes onto the AAC valve at the rear of the intake plenum. Injectors: 
 The top of the injectors should be BROWN coloured, you MUST use Turbo injectors with a Turbo Computer, you CANNOT mix and match, if you use NON TURBO INJECTORS the motor will not get enough fuel, and most likely wont last over a week. Computer: 
You NEED a turbo computer (accept this as a minimum) in order to run the turbo injectors, an Auto computer will run both manual and auto cars, but a manual computer will not run an auto car. Computer Identification
: - 3TA = Turbo Auto
 - 3TM = Turbo Manual
 - 3EA = Non Turbo Auto
 - 3EM = Non Turbo Manual
 If no stickers on cover, Open the ecu, a turbo ecu will have a second green computer board on it for the knock sensor. Oil and Water lines
: They bolt onto provisions made in the later model VL Series commonly known as series 2. It is advised that if you have an early one, to get a S2 motor to use
the water return goes to a heater hose on the other side of the engine with a T piece. Cooling: The radiators in ETs were apparently 3 core, but as you fiddle with the boost and timing, the engine bay will become more and more heat soaked, resulting in damage (melted fuseboxes, overheating, etc). So the cooling system should be in good condition, or serviced thoroughly before the conversion. So guys and girls, Thats my write-up if you think I should add anything else please let me know, this took me a while to write so hope you's like it. Thankyou 5spdvl and others for your help with this write up... Nick... Some original photos have not been recovered yet.
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5spdvlArchived member
Hi Nick, Good write up, but it'll need a tidy up. You've quoted some pictures in your body of text, but not included them. Do you need a hand with uploading/hosting pictures? photobucket.com works well for hosting with CT. Regarding running an MF5 behind a turbo motor; it can be done and done well, but you need to discuss what the issues are. Less syncros in an MF5 = damage when changing gears hard ("slamming" in into gear); however gentle shifting can see an MF5 hold power (reportedly) up until around 220rwkw, where you can start to see teeth being warped and pushed off the gears. Same for the RB20DET boxes, however they have dual syncros and are generally better option when on a budget. You should mention the differences in the clutch; 10" MX7, 9.5" MF5. MF5 clutch is preferable as it is the same diameter as the Skyline series, and therefore gives a much wider variety of off the shelf performance clutch options. The radiators in ETs were apparently 3 core; it might be worthwhile mentioning that as people fiddle with their boost and timing, their engine bays will become more and more heat soaked, resulting in damage (melted fuseboxes, overheating, etc). So the cooling system should be in good condition, or services thoroughly before the conversion. Regarding fuel; Vpower/high octane is not necessary on a standard set up. Fuel maps released on the standard ET ECUs were written on standard RON91 fuel - what was available in '86-'88. When you move onto an aftermarket ECU and get tunes performed on a dyno, then you should discuss fuel with your tuner and have it tuned accordingly. Having said that, if you can afford the premium stuff it is preferable. Compression. The ETs run 7.8:1, Es run 9.0:1. Turbo motors generally have lower compression than their naturally aspirated counterparts to deter knocking. Worthwhile mentioning the chance of detonation (and not detonation as in "blow up", like you've mentioned a few times) is increased on an NA conversion motor. Brakes. Just because you drive the car with the non turbo brakes does not mean they will fail. You could have a jet engine, and if you obey the speed limits your brakes won't fail (from normal driving). It's when you start to increase the boost and reach higher speeds faster that the standard brakes hold their heat just that little bit longer, and reach a less effective state sooner. Having said that, it's advisable to have them serviced thoroughly as a bare minimum, if not upgraded. Everything on VLs is now approaching 26 years old, and it's not worth assuming a part is fine when you're gambling with your life and others. Safety should be budgeted for as part of the conversion. Brakes are only as good as the tires. Anyway, good work Nick. Just tidy it up with some of the above suggestions and it should be a worthy addition to the tech section.
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NiceTintsArchived member
Thanks for the advice mate, will tidy it up and post it in the tech thread asap
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BaxArchived member
Well summarised by Tim, maybe reword the brakes part, they don't exactly fail. But having that mass accelerating a lot more than it used too, it's just putting a lot of strain on them, and they're pretty useless as is. Good write-up, looking back at the old one. Even though there's a tonne of information in it, it's a bit disjointed.
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NiceTintsArchived member
Quote: Originally Posted by Bax [View Post] Well summarised by Tim, maybe reword the brakes part, they don't exactly fail. But having that mass accelerating a lot more than it used too, it's just putting a lot of strain on them, and they're pretty useless as is. Good write-up, looking back at the old one. Even though there's a tonne of information in it, it's a bit disjointed. Yeh I realise this now, ill be re writing some of the "disjointed" parts tonight. thanks Nick
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KALAYArchived member
good write up, you don't NEED a knock sensor, but you NEED your own pictures
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NiceTintsArchived member
Quote: Originally Posted by MaD_WoG [View Post] good write up, you don't NEED a knock sensor, but you NEED your own pictures yeh true, couldnt get pictures from anywhere, so i just googled some parts..
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JaimanArchived member
this will definitely help me with the little bits and pieces. no doubt this whole thread could be built on as is most cases anyone who goes from NA to Turbo probably wouldn't use the stock setup like the crossover pipe, instead they would use a cooler or even a slightly bigger turbo. but none the less a good source of information. cheers
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