cubastreet Posted August 10, 2006 Share Posted August 10, 2006 I have a 1981 subaru brumby ute, the only year with the 70s style body and the 1800 engine. I'm building a new engine for it, starting with the same ea81 pushrod block. I want to make the ute quick but not super fast, and want torque low-down so I'm thinking to supercharge it. The chassis won't fit a subaru ohc engine without hammering/cutting and I don't want to do this. The bores are nice and wide at 92mm and the valves should be big enough for some decent flow so I'll just do some regular head flowing and just leave it at that. The compression is 8.7:1 standard and I'm thinking just to leave it at that and run about 6psi boost with no intercooler. Sound reasonable? Looking at the 2nd hand supercharger market the one off the 4agze engine looks like a possible go, think it may be called a sc10. Sound reasonable? for fuel, I have two options: 1) a twin choke weber. now which would be better: suck or blow through and why? 2)TBI from an EA82 1800 ohc engine and either ecu from that modified or megasquirt. Also, i've heard of switchable s/c setups. the electric clutch is easy, but how does the engine get air when the s/c is off? is it sucking it through the s/c or does another valve open? Any advice/comments/suggestions are welcome Quote Link to comment Share on other sites More sharing options...
Honda Ass Dragger Posted August 10, 2006 Share Posted August 10, 2006 Toyota Does to superchargers, the sc12 found on 4agzes and the sc14 found on 1ggze if i was you id be looking for a sc14 as you are wanting this to be daily driven forget the carbies and try to modify a fuel injection set up to work with a megasquirt as this will give you the best fuel econmy and performance as well as reiblty go the sc14 and 8psi you'll be flying Quote Link to comment Share on other sites More sharing options...
drftnmaz Posted August 11, 2006 Share Posted August 11, 2006 8.7 to 1 is about rite for low boost. but you might want to have a look around wen buying ring try and find some chrome moly insted of the standard ones. carbie would be alright suck-through but no-where near as good as injection so if you can afford to and plan to drive it lots spend the extra money on injection a megasquirt the sc12 (which your most likley talking about) has a clutch pully wen its no turned on then the air flows past the rotors on its own and keeps it spinning alittle bit. on 6psi you dont really need a intercooler but i'd put one in there and just attach it to the intake of the supercharger so it sucking fresh cool air. but nothing too big. something along the line of a isuzu mu cooler that flows nicly. Quote Link to comment Share on other sites More sharing options...
cubastreet Posted August 11, 2006 Author Share Posted August 11, 2006 Maybe I'll do a megasquirt conversion on the original engine first then and transfer it over to the s/c engine when it's done. Don't think there'll be much choice in rings for the pistons in the engine, it's not one that has any aftermarket tuning items or anything. There was a turbo EA82 engine with the same bore, but I think they were dished to reduce the CR even further which I don't really want. I just read that on the 4agze at least, the sc12 increeases the intake temp by about 15 celsius off boost because it's attached to the engine so an intercooler may be a good idea. Can't see what good it would do attached to the inlet of the s/c tho. The spare wheel sits above the engine so if I take that out there's plenty of room for a top-mount but I don't want to cut the bonnet so front mount would be preferable. It must be relatively simple to run a bypass valve to avoid heating the air when off boost right? This car's to be my daily driver so economy and drivability are the main priorities, along with a bit of off-roading as well (it's dual-range 4WD) Quote Link to comment Share on other sites More sharing options...
johnnyfive Posted August 11, 2006 Share Posted August 11, 2006 Hi there Cubastreet. Its me from the USMB I've been talking to a guy down south somewhere whos supercharged his lpg ea81. Its really interesting. Hes planning on doing water injection on it this time round as it blew up the first time. If you want I could pass on your details to him. Quote Link to comment Share on other sites More sharing options...
cubastreet Posted August 12, 2006 Author Share Posted August 12, 2006 Hello mate, is that lpgsuperchargedbrumby you're talking about? I've been meaning to PM him about how he did his conversion as I think he may have used a sc12, but got boost hungry and turned it into a grenade. Yeah tell him to give me a shout and we can maybe swap some ideas, maybe put a knock sensor in the block too. Quote Link to comment Share on other sites More sharing options...
johnnyfive Posted August 12, 2006 Share Posted August 12, 2006 Yep thats the fella. I might pop him an email later tonight or next time I'm talking to him I'll say. Its pretty interesting what he's doing. Custom manifolds and things now too I think. Quote Link to comment Share on other sites More sharing options...
nzsubbie Posted October 22, 2006 Share Posted October 22, 2006 this sounds intressting tell me how it goes if ya end up doing this Quote Link to comment Share on other sites More sharing options...
cubastreet Posted October 22, 2006 Author Share Posted October 22, 2006 It's happening, but on a tight budget so pretty slowly. At the moment I'm mostly doing panel work. Hope to get that finished by christmas to take it to Nelson to spray the whole thing as I know someone with a panelshop there. I've got a rebuilt ea81 with big valve heads which i'll clean up the ports on. Still deciding between LPG (easy option, cheaper in the long run but will need a tank in the tray of the ute which I don't want.) And injection with megasquirt. I've been pretty keen on ms since I heard about it so now's a good time to give it a go. Prolly will make up some carbon fibre inlet manifolds like the aero boys do. Looks simple enough and I have plenty of experience fibreglassing. Pretty much decided on an eaton SC from a mini cooper s. cheap and readily available in the UK (~100 quid) and more efficient than an sc12. Haven't thought much about IC yet, but will prolly fit something as well. Quote Link to comment Share on other sites More sharing options...
Defcon Posted October 22, 2006 Share Posted October 22, 2006 EFI is the way to go, with the throttle before the s/c intake. The toyota superchares wil work sweet with efi, (as above) but shit with a carby setup.(Btw dont go blow-through, its really hard to get tuned right). If you can, try find a differnt s/c, the toyota ones are actually pretty shit, inefficient and produce a lot of heat. Personally i think a suck through supercharger would be the sweetest, not the most effective, but definatly looks the coolect and goes with the oldschool theme. Theres a couple of companys that make some nice suck through s/c's for 4 cyclinders. Some of the harley davidson s/c would suit you well, they look really cool(roots sytle) and come up on trademe every now and then. Matt Quote Link to comment Share on other sites More sharing options...
nzsubbie Posted October 23, 2006 Share Posted October 23, 2006 how much power do ya think ya would get out of it? im thought of supercharging an ea71 motor. but im dont think im worrie bout doing that. im mite just stick to ea71 an fit an webber when im start working on my lil coupe. Quote Link to comment Share on other sites More sharing options...
cubastreet Posted October 23, 2006 Author Share Posted October 23, 2006 I'm not looking for massive amounts of power, ea81s are awesome motors but there's only so much you can reliably get from a 25 year old engine with pushrods and 3 mains. If you want high power reliably you're best off swapping in an ej22. Probably looking to get 120-130hp. I'm more after the extra torque for drivability and the mad max factor of having a switchable blower. Mad fun on dirt tracks Eaton M45 Quote Link to comment Share on other sites More sharing options...
nzsubbie Posted October 23, 2006 Share Posted October 23, 2006 nah cant fit one in to mine to big. anyway im want the fuel ecommony with the reliably. like an lil bit more power Quote Link to comment Share on other sites More sharing options...
cubastreet Posted October 23, 2006 Author Share Posted October 23, 2006 They can be squeezed in apparently, with the help of a hammer to widen the rails. EA81s are a direct swap, easy way to go if you just want a little more power. Cheap as too. I've got a weber and adaptor plate but don't know if I'll even install them might just go EFI and save doing everything twice. Quote Link to comment Share on other sites More sharing options...
nzsubbie Posted October 24, 2006 Share Posted October 24, 2006 im not sure bout that? im imagen your engine bay would be bigger than mine since im got an 1400? im think im say with 1600 and fit the 5 speed box in 2 it Quote Link to comment Share on other sites More sharing options...
johnnyfive Posted October 24, 2006 Share Posted October 24, 2006 I had the feeling that all the pre '80 had the same or very similar dimensions, the '81 Brumby included.... Don't hold me to that though. Quote Link to comment Share on other sites More sharing options...
nzsubbie Posted October 24, 2006 Share Posted October 24, 2006 well the 1600 is like an 1400 thats put on weight. engine bay dimensions mite be the same? can you take the head off in place in the 1600? Quote Link to comment Share on other sites More sharing options...
johnnyfive Posted October 24, 2006 Share Posted October 24, 2006 I'm pretty sure you can pull the heads on mine, looks to be enough space, and its the 1600 body with the 1800 wedged in it. Quote Link to comment Share on other sites More sharing options...
cubastreet Posted October 24, 2006 Author Share Posted October 24, 2006 ea81s are the last subbie ohv engine, narrow enough to fit in the 1600 chassis rails without modification. Pretty sure the 1400 had the same chassis. 5sp would be good. I'd do it to mine but with dual range 4wd the levers are in different positions and I can't be bothered with cutting up the tunnel. Gives you the option to put in front LSD which might be nice. Quote Link to comment Share on other sites More sharing options...
nzsubbie Posted October 24, 2006 Share Posted October 24, 2006 with the 1400 ya cant take the heads of in place. ya need to pull the motor out. if im fit the 5speed front wheel drive box in im have to get some gearbox mounts made or something. im no its been done but its is tight Quote Link to comment Share on other sites More sharing options...
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