Guest Anonymous Posted January 4, 2001 Share Posted January 4, 2001 Guys, I think you have me going toward the SBC, is there any real power advantage to going to a 327? My understanding is that it is essentially a 350 block with a 305 crank. If I am carrying the same weight around why not go with the 350. If however I can build a screamer of a 327 that can equal or exceed the hp of the 350, than by all means I will go that way. Other than the aforementioned book, are there any web pages dedicated to SBC performance/racing applications? Also, any ideas yet on the weight of the 350 iron block, with aluminum heads vs. the L28? I know an alumnimum block is rediculously light by also rediculously expensive! Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 4, 2001 Share Posted January 4, 2001 You can easily do a decent v8 or a l28t for $4k. You can probably even get a whole lt1 drivetrain for under $4k I bet. Scottie even got 300 at the rear wheels with the stock turbo! A complete l28t weighs in the high 400 pound range, so going lighter is easy unless you have some solid iron monster. John said: I'll be the first to add that the Superchargers are not the power robbing complicated, expensive systems as you proclaim.I'll agree that roots type blowers are inefficient, but beg to differ with centrifugal. The adibiatic efficiency of centrifugals is nearly identical to turbos. Almost all engines have some sort of turbo manifold readily available - 6 cyclinder L engines, SBC, SBF, almost all jap engines, and most older domestic engines. This makes turbo use very easy, as making a reliable manifold is the most complicated part. While the efficiency of a supercharger compressor can often approach that of a turbo, add in the belts and gears and a comparable turbo will virtually always come out ahead. I'm not saying superchargers suck, I'm just saying that they are pretty much universally inferior to turbos. ------------------ Morgan http://z31.com/~morgan/s30 http://carfiche.com Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted January 4, 2001 Share Posted January 4, 2001 Roamer, I built a 327 for my Z, it has Twist Flow Aluminum heads,Comp 270H hydraulic cam, roller rockers, Forged crank (all early 327s had them), and an Edelbrock Pro-Flo EFI. The cost was a bit over 4K, but on the engine dyno it made 435hp, and 493 ft lbs tq! it rev'ed well over 7k with out a problem. ------------------ http://members.tripod.com/~SnowSurfer/mikekz1.html Quote Link to comment Share on other sites More sharing options...
John Scott Posted January 4, 2001 Share Posted January 4, 2001 Sorry Roamer, Welcome to the site Hope you can sift through this and come up with some good ideas for your project. Don't discount the sbc for its high rpm potential. I ridden in some 10K rpm cars, (and one truck actually). Incredible! I think you'll find that the high rpms won't be needed with all the v8 torque, if that's your direction. If you can afford it, a small engine will benefit more from a turbocharger. Morgan, I'll agree with you that the turbos are a more effecient power adder. You say superchargers are "universally more inferior" Turbos require the highest initial investment. complexity, and require EFI. In my mind, this isn't a superior point. Many here a drag racers. Power adder of choice? Superchargers. Why? They are versitle, inexpensive to turbos, and work REALLY well.A single DM3 procharger will pump out 2900 cfm! That equates to over 1600hp potential! Need to switch from your V6 to a sbc V8. No need to change a compressor housing. Mine can be removed and bolted on any smallblock in less than 30 minutes. Ease of installation goes to the supercharger too. Reliability? Most can come with a 3 year warrantee. I have over 5 years with only a $3 seal that needed replacing. If you dig through the archives you'll note I was proclaiming the turbo a superior unit from early on. I'd prefer one under my hood. Yes, turbos are mechanically more efficient. But they cost waaay more, are more complex to configure to a non-traditional engine in a Z. I'd rather be driving my car right now, blowing the doors off the competetion, than saving and dreaming about a high tech turbo. You know what? I like the nasty whine that annouces the arrival of the winner, too. JS [This message has been edited by John Scott (edited January 04, 2001).] Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 4, 2001 Share Posted January 4, 2001 A supercharger is only cheap if you use a carb with it! How much does a supercharger kit cost? $2-3k minimum right? Neglecting an injection system, you can do a turbo for that easily! All the supercharger kits I see for camaros and mustangs are in the $3k price range and up..... that's not cheap in my book. Keep an eye on ebay and the like, you can find small block turbo manifolds and things like that all the time. http://cgi.ebay.com/ebaymotors/aw-cgi/ebayISAPI.dll?ViewItem&item=533016687&r=0&t=0 http://cgi.ebay.com/ebaymotors/aw-cgi/ebayISAPI.dll?ViewItem&item=536396497&r=0&t=0 There's 2 pair of SBC turbo manifolds and misc. bits. One is an almost complete setup! ------------------ Morgan http://z31.com/~morgan/s30 http://carfiche.com Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 4, 2001 Share Posted January 4, 2001 Roamer, Theres no reason not to go 350. They're more plentiful and you can get a 4 bolt main. Reason we started on the 302 and 327 was because they could RPM real well. The 350 gives up a little in the way of RPM (which is not to say it won't, but it doesn't rev quite as fast as the small, shorter stroke small blocks) but does give a little more torque down low and in the mid range. You can build a 350 on the mild side and easily surpass your 300 hp specs. The transmission you'll probably want to use is the T-56 6 sp. although a bit pricey, it's beefy enough to handle most any small block. If highway cruising isn't important (i.e. overdrive), then a Muncie 4 sp could be used, it'll more than handle the small blocks as well. A T-5 5 sp. may work, but if your gonna race it, might be a little weak (they're good up to maybe 330 ft/lbs of torque which you probably would be surpassing). To pull it all together for 4k will require a sharp pencil, but if you shop around, get some parts from the dismantlers and classifieds (good sources of blocks and older iron heads, intakes, somtimes complete engines requiring only a refreshening etc.) you should be able to do it. Good luck with it, Lone Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 4, 2001 Share Posted January 4, 2001 Morgan, what steps are necessary to build a strong, reliable L28 turbo, with even power application (don't want mid-corner boost spikes) and minimal complexity? What are the costs? SBC preachers, I was only considering an engine with aluminum heads and intake manifold, plus the other lightweight accessories to keep overall weight to near stock levels. Any ideas on getting LS1's for reasonable dollars? As for trannies, I don't want to go 4 or 6 speed for various reasons, any 5-speeds out there that could possibly bolt to an LS1 or a built iron-block 327/350 and take 350+ ft.lbs of torque in racing conditions? Thanks, this has been great! P.S. Why no talk of the Buick 3.8 Turbo, they did mate it to a 5-speed in the 25th anniversary TransAm didn't they? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 4, 2001 Share Posted January 4, 2001 I dunno, ask the people who have done it. It's plenty stout bone stock for the 300hp you want, no need for any work that will eat up your budget in no time. If you wear the engine out, blow it up, or whatever, just get another $500 low mile junkyard engine and pop it in. ------------------ Morgan http://z31.com/~morgan/s30 http://carfiche.com Quote Link to comment Share on other sites More sharing options...
Modern Motorsports Ltd Posted January 4, 2001 Share Posted January 4, 2001 quote: Originally posted by Roamer: SBC preachers, I was only considering an engine with aluminum heads and intake manifold, plus the other lightweight accessories to keep overall weight to near stock levels. Any ideas on getting LS1's for reasonable dollars? As for trannies, I don't want to go 4 or 6 speed for various reasons, any 5-speeds out there that could possibly bolt to an LS1 or a built iron-block 327/350 and take 350+ ft.lbs of torque in racing conditions? Ls1's aren't cheap and neither is mating a trans to it (and an Ls1/T56 OEM combo [Ls1 T56 is diff. from Lt1 T56 trans). An OE Lt1/T56 setup would do you very well. I know it's a 6 spd but stand. trans that take the torque are pricey and those take it as is and are a nice trans. The Lt1 can get you your 250rwhp sleeping; with v. easy/cheap mods you'll get a fair shake more keeping the same cam. A bit of wiring to sort out but once done you have a v. reliable/smooth and efficient motor (no large fuel cell needed for enduros;^). Someone on page one (V8Zed?) mentioned his trickflow sbc twisting 7000 no problem. Sure it'll twist 7000 no sweat but what does the dyno curve show? Peak HP will be below that w/ hydraulic lifters to no gain running their with lifters floating a bit, that can get to pushrods acting like air chisels (don't ask....8k wasn't good for only my pushrods and one rocker, gotta love a chevy:-)) 6600-7000 is top bag for any hydraulic lifters and normally a rev kit and particular non-soft lifters are needed to get that. 6500/6600 is more norm for that. I'd also reccomend driving any similar sbc/light car setup you can come across...it's already tons of torque to be shifting at lower rpm's (5-6.5k) let alone up their in 7's:-)) If you must have those rev's I know it can be done but valvetrain costs go up a fair bit as springs/lifters etc see a lot more abuse, I don't recall the exponential relationship to rpm for wear but it's significant. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 4, 2001 Share Posted January 4, 2001 Part of my need for rpms is the difficulty in finding datsun rear ends that are geared lower, most are in the high 3's if I remember correctly. This means the engine may scream in certain situations where holding a gear is necessary. I am not necessarily looking for peak hp at the 7k range, just that the motor run strong at that point and without concern over valve fload/pushrod damage/cam problems. -I am sure that 200+ hp at 1500rpms will satisfy my need for speed. -What is the deal with the 6-speed, will I need to modify the tunnel even with the 6-speed from the LT1? -What are the costs/availability of an LT1, and do they have aluminum intakes/manifolds to keep the weight down. From what I understand the LS1 is 100lbs lighter than the LT1, is this due to the iron vs. aluminum block alone? -Last, can I buy an LS1 block only, then use it to build a real light 327? Thanks! Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 4, 2001 Share Posted January 4, 2001 r200 diffs are readily available for $100 or so in 3.54-4.11 ratios. You can also significantly change tire diameter to change gearing, and with any decent 5 or 6 speed transmission it's not exactly an issue worth worrying about. There is a company that makes a LT1 wiring harness specifically for transplants... it plugs right in and disables the burglar alarm and I think that skip-shift thingie as well saw an ad for it just last night in some magazine at books-a-million. LS1 is a new engine, just like lt1 is, and I'd bet both my nuts that it shares few, if any, parts with any other engines. ------------------ Morgan http://z31.com/~morgan/s30 http://carfiche.com Quote Link to comment Share on other sites More sharing options...
Arif Posted January 5, 2001 Share Posted January 5, 2001 Roamer, I ran across this article written by the folks from Bell Engineering. It discusses their decision on NOT going with a supercharger and instead using a turbo on a BMW M3. According to them the SC is not the answer to low end power as many of us think. Just something I found and thought it was interesting. http://www.bellengineering.net/BMWM3Turbo.htm ------------------ http://communities.msn.com/TurboZ Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 5, 2001 Share Posted January 5, 2001 I've never been overly impressed with corky, but they sure do make some nice stuff. While generally true, there are some stretches on that page..... they say a supercharger's boost varies with the cube of speed, but that is blatantly false. The exact relationship between speed and boost is fairly linear across the compressor speed range, but varies depending on the compressor and gearing.... I have seen as low as 2.1 and some even over 3(the figure corky cites). "Power robbing turbulence right behind the turbine" Hah! All the respected turbo people say a rapid and violet expansion of the exhaust as soon as possible after the turbine is good because it forces the rapidly spiralling flow to break and become turbulent, creating less pumping losses in the exhaust. Note that all the turbo tom's kits adhere to this theory, as do all callaway turbos, etc, etc, etc. ------------------ Morgan http://z31.com/~morgan/s30 http://carfiche.com Quote Link to comment Share on other sites More sharing options...
Evan Purple240zt Posted January 5, 2001 Share Posted January 5, 2001 Well this has been a very intersting set of flames i have seen on this thread. Ouch. First off, if you decide to go an L turbo motor. Do not rev it to 8k lol. I honestly think you are on the right track with the larger displacement motors. This is coming from the mouth of an Lmotor user. Hey morgan, how many turbo motors have you built? The reason i ask is because you bring up some things I have never heard. Honestly, in the world of the L motor im a strong beliver in overbuilding. Keep in mind if you want a forged lower end it will run you about 800 w/rings. I have spend way too much on this motor, and its too late to turn back Honestly, i think the chevy or the like will make roamer the happiest. Oh, and BTW, even the best setup turbo will have lag. Thats just the way it is. Just a couple cents for ya- Evan PS i can offer more detail on my motor setup if you would like to email (if you care) Quote Link to comment Share on other sites More sharing options...
John Scott Posted January 5, 2001 Share Posted January 5, 2001 My 600 billit impeller complete with all brackets, carb hat, and pulleies was 2071.00 I'm sure this has gone up. In all fairness I inquired about the centrifugals hp requirements. It takes about 60+ hp to turn a 600B at 15 psi, give or take. On a Smallblock this would equate to roughly 600hp. Sounds like about 10%. I don't know what the back pressure equals to hp loss in a turbo motor, but its not that high. Also, as Morgan mentioned, the turbo impellers are capable of more speed. Centrifugals are closing the gap, but have a ways to go. Advantage: Turbo. JS Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted January 5, 2001 Share Posted January 5, 2001 roamer-chevy offers new lsi motor in crate with off road computor & harness -i heard around $6000.nothing from lsi fits older engines -ls1 is all new.i am working on a 66nova ss/94 lt1 swap in garage for a customer right now.engine has aluminum heads but not a lot of sbc parts fit because of d shaped exhaust ports,reverse flow cooling and more.chevy has a fuel injected 350 crate motor that is plug&play for about $4500.when i was at thunderhill i saw a late model rx7 with a 3 rotor 20b motor.a perfect road race motor.9000 rpms easy and 300 hp with no turbo.with good turbo and efi system 500 hp easy. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 5, 2001 Share Posted January 5, 2001 Are you guys saying that I am better off going to an older block sbc, rather than getting into a LT1 or LS1 for cost purposes? Aslo can I get either of these motors to rev for reasonable dollars? And along these lines should I just buy a 4-bolt main block and build her up or go looking for a full motor and make mods? Further, would it be cheaper to build an ironed block sbc with aluminum heads, intake, lightened accessories than purchase and improve a LS1-LT1? I think Edlebrock is building one now that goes for around $4k. If I remember correctly this setup is almost equal to the L28 in weight according to JTR. Again equal would be sufficient, these cars are front heavy enough, I don't want to make it worse. Hey, how do the R200 rear ends and half-shafts fare with 300+ ft.lbs of torque running through them, is this another issue I have to consider? Quote Link to comment Share on other sites More sharing options...
Mikelly Posted January 5, 2001 Share Posted January 5, 2001 Roamer, Not sure what your intended use is, but You can make the power you want with either direction you go in. I honestly think that, unless you know a lot about FI and forced induction, you will run into some huge troubleshooting just in dialing in your FI and turbo. If you have the tools and know-how, then half the battle is won in going turbo, but consider that before you make your decision. Now, GM performance is now making the new ZZ4 RamJet 350 motor for about $4000 complete with computer, harness and everything you need for an FI small block chevy. Then you can pick your transmission and go from there. 350flywheelHP and variety of transmissions (Including the Tremec and BWT5) will work well with it. I'd investigate all your options thoroughly and base your decision on the support you will have in your area, and what you can afford. Also, base it on reliability. Don't read into that that turbo motors aren't reliable, as they can be very reliable, but Evan makes some very good points in his above post, and he is an L6 Turbo owner... Mike ------------------ http://hometown.aol.com/dat74z/myhomepage/auto.html "I will not be a spectator in the sport of life!" mjk Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 5, 2001 Share Posted January 5, 2001 If you really want a v8, why not just get a drivetrain out of a camaro or whatever? low mile lt1, t56, plenty of power, and can be had for well under $4k.... Better yet would be to turbocharge such an enormous engine. Monster engine.... boost.... I bet it'd be nice and fast A good condition r200 will take nearly anything you can put through it. If it blows up, low mile replacements are readily available for cheap and they're easy to swap out. What things do I bring up that you have never heard of evan? If you're selling your engine, I'm buying ------------------ Morgan http://z31.com/~morgan/s30 http://carfiche.com Quote Link to comment Share on other sites More sharing options...
pparaska Posted January 5, 2001 Share Posted January 5, 2001 Roamer, welcome! I think if you are going the SBC route, things will be much cheaper with an LT1 or older engine. The Lt1 has a broad torque band, but it won't rev to 7k without alot of money in the valvetrain. A cheaper way to go would be an old style buildup with good forged rods, good bolts (rod, main, etc.), aluminum heads (AFR, twisted wedge, etc.), aluminum water pump, aluminum manifold. Of course, I'm assuming that you'd carb it to do it cheaper. If you want EFI ,that's more money for sure. You've got to ask yourself whether you really need that last 5% of horsepower and the tunability of EFI, for the price. Deals can be had though to help this out - just ask Ross! For the money, the carb is it for me - until I get rich or something. Still, an iron block SBC with AL parts is a halfway light motor (about 525 lbs or less, I believe) for all the displacement capability. Compare it to a 2.8 or 3.1L L6 and you'll see what I mean. Plus the CG placement issues. The Ford SB is lighter though, by 75-100 lbs, I believe. It's hard to compare weights exactly from the published numbers, as everyone includes different parts on the engine. I agree that a solid flat or roller cam with good springs, light pushrods, light rockers and maybe even titanium valves will be needed to reliably turn 7000+. THe issue is that you probably don't need the extra 500-800 rpm over the 6500 rpm that cheaper parts will give you. All these engines can be built to give 300 hp and rev to 7000. It just depends on which way you want the power. The SBC and SBFord can do it normally aspirated in a very simple and streetable fashion. The smaller engines can do it with either unstreetable huge cam, etc., or forced induction. My opinion is that a simple, crude, NA V8 can make 300 rwhp easily, cheaply, and it's very robust and driveable. No worry's about octane, too-lean -for-a-second-under-boost piston damage, etc. that high boost smaller turbo engines have. But it's so low tech, some people don't want it. The Turbo L28 with forged parts is a very effective way to do this. Not sure you could do a Forged piston L28T with all the reliablity upgrades I'd want to keep the 300+rwhp running for $4k total swap cost though. But as Morgan said, you can buy a few shortblocks from the yards and just dispose of them as you break/wear them out if you go too lean or otherwise detonate. Not the way I'd want to do things, but it's a workable scenario. Just my opinions, others are SURE to vary. ------------------ Pete Paraska - 73 540Z - Marathon Z Project pparaska@home.com Pete's V8 Datsun 240Z Pages Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.