desert dog Posted August 30, 2005 Share Posted August 30, 2005 I have been lurking on this forum for awhile and have learned a lot about stuffing modern American iron into a 240, 260, and 280Z's. The question I have and could not locate by searching was if anyone hase used the Vortec Truck iron block V-8's as a swap engine. Everything I have read says they are of the same dimensions as an LS1 but are 75 lbs. heavier due to the iron block. I also do not know if the engine mounting is the same either. My project is leaning toward the LR4 4.8 liter V-8 for better gas milege. I mean the engine puts out 280+ HP which should be plenty for a daily driven car. The EPA ratings for this engine in a Silverado 1500 is 17/21. I figure it should get a least that much pushing around a 2500 lb. Z-car. I plan on leaving the engine basically stock except for possibly headers and a K&N cone filter. I have also read on this forum that the LS1 may actually be too light for optimum weight balance of the car. Has anyone here done the research to see if the truck motors are too tall for the engine compartment of the Z, or has anyone put one of these motors in a '70-'78? Quote Link to comment Share on other sites More sharing options...
v8dats Posted August 30, 2005 Share Posted August 30, 2005 there some pics of a z with a vortec engine i have some i will read the posts on posting pics Quote Link to comment Share on other sites More sharing options...
v8dats Posted August 30, 2005 Share Posted August 30, 2005 [imghttp://img15.imageshack.us/img15/2978/ljj5ze.png' alt='ljj5ze.png'> dont know where i found them but had them for a while and my first pic post! i SEARCHED and found out how to. thanks tim! Quote Link to comment Share on other sites More sharing options...
zgeezer Posted September 1, 2005 Share Posted September 1, 2005 I've been "in the process" of this swap for the last two years. I expect to actually set an LM7 into a early 71 240 sometime this month. Here's what I "think" I know. There are many small and a few large differences between the LS1 [which most folks are using] and the truck motors. * The truck engine is an iron block, not aluminium. * The truck pan is deep and would not likely clear speed bumps. Change it for a LS1 pan from a Camaro. Don't forget to use the Camaro oil pickup tube. After you button up the new pan, be sure to remove it and check to see if your oil pickup pipe has moved. I understand the clearances are close and if there is any interference at all between the new pan and the oil pickup pipe it will push the oil pickup tube out of the oil pump's "o" ring seal. You can start up w/o oil... not a pretty sight. * The trucks have a "mechanical" fan with a fluid drive... just like yesteryear. My measurements place this fan very close to the middle of the engine. I believe I can run this fan with a radiator shroud... Just like the JTR book. As I've not placed my engine in the compartment, I'm not certain if this will be a slam dunk [i've got to be kidding] or if I will need to modify the shroud. The backup position is a Ford SHO fan. * Other than the AC, all accessories are mounted differently that the LS1. Basically, the alternator and power steering are on the driver's side. The alternator is mounted higher. Additionally, and here's a rub: The accessories are mounted further out from the block and closer to the radiator that the LS1. This means that you can replace all the accessories with those from a LS1, but you will also be replacing the crank dampener and pully. * The intake manifold is tall and uggggggly. The ugly part can be alleviated by using the cover and rail cover from a Cadillac Escalade. However, it will still be too tall to fit under your hood. Take a close look at the photo of the swap engineered by AutoBacs for an idea of the problem. * The two solutions I'm considering are: 1) Cut a very large rectangle in the middle of the hood and then cover it with a fiberglas copy of the "Competition Hood Scoop" that was optional in 1974 or so. It's not a scoop, but a vent. Google "Datsun competition hood scoop" and you'll find some photos; 2) Replace the intake with that from an LS1. It will bolt on, but there are a number of points of interference. Most of all the hoses will be rerouted or replaced with LS1 pieces. Your MAF [Whatever that unit is that measures air intake] will now be mounted several inches lower and, I think a bit forward of the truck position. It will kiss your accessory drive belt and tensioner. The folks at Street & Performance out of Mena Arkansas tell me that all I have to do is cut the tensioner arm and lower the belt. They are confident, I'm not; and 3) replace all accessories and intake manifold with everything from an LS1... this could be pricey. * The 2004 LM7 I'm using has a smaller electronic plug to the injectors than the LS1. You can't use a loom designed for the LS1 * I'm using the corvette motor mounts and isolaters. Use search for the post that will give you dimentions for a simple cross member mount. * Exhaust manifolds are cast iron and IMO good looking. However, after I measured the engine from the rear transmission mount forward [which for me is a given b/c the JTR rear transmission mount is welded in] I believe the passenger side manifold will interfere with the firewall. My cure was to buy a set of JTR headers designed for the LS1 swap. I'm reasonable certain they will fit or can be MADE to fit. * There is a reason that the only photograph I've ever seen of this swap is the one posted above by AutoBacs. You will notice that in that swap the iron manifolds are used, but that the engine is set very much forward and that there is no hood. * But for the fact that I got this very low mileage engine/trans for nickles and I expect to supercharge it [i like to lower compression ratio], I would recommend that you look at the LS1. The prices are coming down and there are kits available that will ease the installation. * I believe you can save yourself a bit of grief If you contact JTR and price out their entire kit, including the headers. Pull up John's Cars website and price out his installation kit too. Then, really learn how to use the search function here. Finally, spend some money and purchase the GEN III engine swap DVD from Street and Performance, it's less than $20.00 and will answer most of your questions about the differences between the truck engines and the LS1. G Quote Link to comment Share on other sites More sharing options...
desert dog Posted September 1, 2005 Author Share Posted September 1, 2005 Looks like it is time to buy some literature. Thank you zgeezer. Mike Quote Link to comment Share on other sites More sharing options...
9kredline Posted September 1, 2005 Share Posted September 1, 2005 Looks like it is time to buy some literature. Thank you zgeezer. Mike Wow, nice to see you from 3ZC.com. Sure you'll end up as positive an influence here as you were in the Tech over there. Quote Link to comment Share on other sites More sharing options...
jonus079 Posted September 7, 2005 Share Posted September 7, 2005 i too have been really wanting to do this converstion. in the beganing i wanted to do an ls1 convertion but after seeing how many people have done it and how much the engine is i figured the lm7 would be much better for my application. my plans are to use a lm7 with a turbonetics 62-1 turbo running low pressure until i get enough money to bore it with lower compression forged pistons. the stock 9.5:1 compression ratio along with the iron block should be able to hold 6-10 psi with no problems as the effective compression ratio is still pritty low. see the thing is i could send $4k for an ls1 w/ 4l60e (340hp i think it was) or i could get an lm7 (295hp) for $700 with the same tranny (and they are easy to find at that price). turbo that for around $1000-$2000 and then in the future have it bored to an ls1. now of corse there arent as many performace part for these engines as the ls1 but there is still a good amount out there. cam, heads, headers, maf's, etc... can be found at summit and im sure if looked i could find alot of other parts. as for the headers, you can pick up a set of tubular headers from summit racing for only $169.99. they can easly be modified to fit better. in the end for me it all comes down to money, in my opionion this engine gives alot more bang for a buck than that ls1. not that im knocking the ls1, if i had the money i would buy one! if you target is to run 9's then get the ls1 but if you happy with anything after that then the LM7 and LR4 are great alternatives. hey zgeezer, do you konw it a t56 from a ls1 would bolt up. i was told it wont but have trouble believing that as the camaros have the same auto as the trucks. Quote Link to comment Share on other sites More sharing options...
desert dog Posted September 8, 2005 Author Share Posted September 8, 2005 Thanks for all the replies... Waddup 9kredline... The main reason I am looking at the LR4 instead of the LS1 is performance vs. fuel mileage. It also helps that the engine is 1/3 the price of an LS1. This car will be a daily driver so the engine will remain completely stock other than intake and exhaust. I guess what I need to go find out is if all the mounting points on an LR4 block and heads are the same as an LS1. I think I have a line on a '98 Camaro with a dead 5.7 in it to scarf all of the needed components out of.... If not, I need to find a tasteful hood scoop that does not ruin the fantastic lines of the 1st generation Z car. Hopefully, the OEM LR4 intake plenum can be beautified some as well in that case. Quote Link to comment Share on other sites More sharing options...
desert dog Posted September 12, 2005 Author Share Posted September 12, 2005 I ordered the JTR Datsun conversion manual this weekend. I also found a Motorbooks repair manual for the 1st generation Z's on Amazon that I bought as well. I am excited about this car because I have built two cars in the past five years for my sons, and now the old man gets to build one for himself... I will have some 240Z parts for sale soon as well. I am going to part out the "parts car" that came with the car I bought. More questions will come up that I haven't found doing "search"... Mike Quote Link to comment Share on other sites More sharing options...
Cable Posted June 6, 2010 Share Posted June 6, 2010 Another run at the top... Quote Link to comment Share on other sites More sharing options...
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