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Tech Article: EFI 304 into VL

Started by PROGMH · 12 Mar 2008 · 263 replies

Preserved from CalaisTurbo (partial recovery). Original authors and dates are shown; archived members are not current Holdcom accounts.

PROGMHArchived member
I thought I would put all of the info from alot of threads together so that people can use this instead of starting 5+ threads a week asking the same questions! Can this be made a sticky in the V8 Section Its not all my work but I grabbed alot of info off everyone - so thankyou to those who have previously helped out - mainly CHEETR The things you will need to put an injected 5 litre into a VL are: - EFI 5.0 + TH700 auto - ECU - K Frame (VL or VN V8 - VN V8 one is cheaper) - 1inch Master cylinder - Headers - Exhaust (exhaust shop) - Engine Loom (VN V8) - Radiator (VL V8) - Cold air intake (optional) - Tail shaft (Custom or use a V8 TH700 front tail shaft and a VL rear tailshaft - can anyone confirm this?) - VN V8 accelerator cable (you may need to cut it to fit) - you may also need to swap the body loom as some v6 ones arnt the same also when going through the trouble of doing this i usually buy all this gear aswell for it - New engine mounts (VL V8) - New crossmember mount for the gearbox (VN V8) - new plugs - new leads - New dizzy cap - Coolant for the radiator - new Pulley belts - New Panel Filter - Flush the radiator - clean the throttle body out - Dump the oil and put new gear in - Service the tranny, can buy tranny service kits if its a auto. If you're going for the TH700 then youll need to beat the floor up a little to fit it as its a larger box than the ones VL's had. You may also need to get a VN V8 dash as it has the speed sensor in it that the auto elec will need to make things work - saves buying the part that replaces it for over $200! You dont need to install a VN dash into your VL but you will need the speed sensor that is in the VN dash for everything to be wired up correctly. If you dont have one of these its just another cost when you see an auto electrician and they need to purchase the part that does the speed sensors job. (Cant remember what its for or what its called... can someone help?) Youll need to run a fuel return line to the tank / surge tank if you dont already run EFI. If you're running an N/A 3 litre then you will need to upgrade the brakes to VL turbo or VL V8 or better as well as upgrade suspension to handle the extra weight and power of the replacement motor. If starting with a VL V8 you will need to move your battery to either the boot or to the other side of the bay because it will get in the way of the EFI 5.0 air box. This info is the same for VN - VT 5 litre conversions of both Holden and HSV motors! If I've missed something please let me know or if you have any tips and Ill add them. It just saves us reading a heap of threads and answering the same questions on a daily basis! If someone has a step by step picture sequence then pass them onto me and ill work them into it. Brett
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EAT-30TArchived member
Good stuff... make this one a sticky someone!!! Your missing something on that list though!!! Some original photos have not been recovered yet.
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PROGMHArchived member
Feel free to add suggestions of 'necessary required parts' then. A blower or turbo set up is not required, but would still be fun.
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EAT-30TArchived member
Quote: Originally Posted by PROGMH A blower or turbo set up is not required, thats what I was gettin at LOL Some original photos have not been recovered yet.
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NZ EVLHSVArchived member
Good idea, this should be made sticky I know it doesn't say anything about diffs up there, but in case people are wondering, no you don't need to upgrade to a 28 spline diff, the stock 3L 25 spline will do the job (on a stock'ish 304)
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xeturboArchived member
as for the tailshaft solution, ive heard u use the front half of the VN (donor car) tailshaft, and connect it to the rear half of a vl one. apparently this works with no issues at all.
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WaughyArchived member
And if you start with a 5L you need to change tanks for a 6cyl one, and upgrade the return line, right? Battery needs to move, either to other side or boot if you're keen enough. I want to saty carby and original, but the EFI bug is pestering me, lol.
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PROGMHArchived member
Why would you need to move the battery and change fuel tanks? You wouldnt need to upgrade the return line unless its knackered. If it were me I would run a lift pump to a surge tank with the return line filling the surge tank back up.
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WaughyArchived member
Only going from what I've read around the various forums so far. The battery sits on the left side on a factory V8 VL, right where the airbox for an EFI motor would go. Was told the tank needs doing for the pump inside the tank and the return line is either smaller or bigger for EFI, can't remember but guess it's got something to do with pressure. I like your suggestion but, anything to save rooting around. Is a top end conversion worth looking into, or go the whole hog with a full donk and TH700?
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PROGMHArchived member
Quote: Originally Posted by Waughy Only going from what I've read around the various forums so far. The battery sits on the left side on a factory V8 VL, right where the airbox for an EFI motor would go. Was told the tank needs doing for the pump inside the tank and the return line is either smaller or bigger for EFI, can't remember but guess it's got something to do with pressure. I like your suggestion but, anything to save rooting around. Is a top end conversion worth looking into, or go the whole hog with a full donk and TH700? Yep you would need to move the battery then! I wouldnt think you would need larger return line because there isnt a heap of fuel travelling through there. I cant see why you would need to do the tank, but you would need to change the fuel pump because the EFI requires alot more fuel pressure than carby to run. I'd do the whole engine because at the end of the day its newer, stronger crank and rods. TH700 = 4 speed too! Bonus!
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NZ EVLHSVArchived member
Best to start with a 3L. Cheaper, no need to change fuel system, better diff ratio, no need to move battery...
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WaughyArchived member
Excellent, now I just need cash, lol. Good write up so far, save on all the separate threads with bits and pieces of info. I'll be keeping an eye on this one. Is the 6 really a better start? The 8 already has the k frame and suspension, probably the biggest part of the job after fitting the engine, in order of time and difficulty. Wiring has to be done the same on both, and by the sound of things you don't necessarily have to do the tank so that cuts out a fair whack of time. Guess it's much of a muchness, just different things you have to do depending on what you start with.
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xeturboArchived member
the k-frame is only 4 bolts, plus the associated suspension with it. k-frame swap is easier, especially from a donor car as it already has the better brakes etc (VN V8 etc.)
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PROGMHArchived member
Thanks for the extra info. I keep updating it as you guys help. Keep it coming if theres anything that hasnt been mentioned. Id like this to be a comprehensive guide.
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hsvhelArchived member
put a second outer pump on the tank feeding through one another, or shell out for one bigger unit. the external will need to be one of the above
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Psi_WagonArchived member
Quote: Originally Posted by xeturbo as for the tailshaft solution, ive heard u use the front half of the VN (donor car) tailshaft, and connect it to the rear half of a vl one. apparently this works with no issues at all. that will work ONLY if you use the rear half of a V8 or Turbo tailshaft. the n/a tailshafts are smaller and the centre wont line up. as for the fuel issue, you Do need to use a 6cyl or EFI tank, the EFI tank has larger return line than the carby tank, and breather and return assemblies are different. the return line IS larger on EFI vl's, strongly recommend u upgrade it if its was a carby V8 nearly everything you need to know is here ---> http://www.brockcommodores.com/vbull...efi+conversion (http://www.brockcommodores.com/vbulletin/showthread.php?t=817&highlight=efi+conversion) cant get more comprehensive than that!
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calaisv8Archived member
brilliant thread guys makes things alot easier rather than searching all different threads cheers
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leb vltArchived member
my mates wagon houses an efi vn 5ltr with a manual and he used the front section of a vn manual tailshaft and used the rear section of a auto v8 shft of his vl
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sheepz89Archived member
i have a couple of questions about the transplant: 1. Do you need a custom exhaust, or can you use VN headers and will it fit to the VL V8 exhaust? 2. Which gearbox is best for a manual? 3. I have heard rumours that there is also a problem with crossmembers and steering rack, also with the cooling system (radiator, i assume with hoses) can anyone help?
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NZ EVLHSVArchived member
1. VN headers fit but will have to modify your existing exhaust to match up 2. T5 is probably the cheapest and easiest option, but all comes down to how much power you want it to handle and how much money you have. I used a Getrag (VT S1) which are much stronger boxes but are fairly rare and you need an electronic speedo - VS cluster does the job and fits ok 3. I didn't have any problems with these. A VN-VS V8 radiator works fine
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