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OlderThanMe

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Everything posted by OlderThanMe

  1. On a flat plane V8, you do not need to take the connecting rods/pistons into account. They statically balance each other out. I looked at summit again and I guess they don't carry an OE SBF block any more. They do have a Ford racing 5.4L modular block for $500 though. LINK About the crank being more solid: That is my theory. From what I have read, the more bearing journal overlap that you have, (rod vs. mains) the stronger your crankshaft will be. With more stroke you have more of a lever acting on the crankshaft and are putting more twisting forces on the entire crankshaft. For the I4 cams, I know that most I4 engines have a rather small bore spacing. For example, the VH45 has 112mm bore spacing while most Nissan 4 cylinder engines have around 100mm bore sacing. About the Ford specific stuff, I have no idea. I'm not really much of a Ford guy. I hope that helped. OTM
  2. Well, a VH45 has a 93mm bore stock, which is ~3.66". There is somebody that has supposedly put a 305 SBC rod and piston into a VH45 with minimal work........ The Ferrari 355 flat plane V8 makes ~375hp out of a 3.5 liter N/A dry sumped motor. Its not that Ferrari did anything particularly special there, they just had good planning. Donor motors for naturally aspirated flat plane V8, I think the number one consideration is the ability to rev high and not explode.(valvetrain mostly) The second consideration is for the head to flow the amount air as not to choke the engine at high RPMs. (near stock or smaller than stock sized ports on a single cam V8 engine) The VH45 starts out with a VE of about 92% which isn't bad at all. Stock ports would be fine for a smaller displacement engine at higher RPMs plus their highly aerodynamic design really helps. (necks down a slight amount half way into the cylinder head intake tract) For a rotating assembly/valvetrain package I believe it would cost about $5000 plus engineering costs at ~$75-$100+/hr. Now if you can think through the whole ordeal and learn all you need to know(Homeschool yourself! read books!!!!!!!) and design the crank, cam profiles, valvetrain stuff, etc... then it may be cheaper, and props to you for the endurance.
  3. Gollum, All of the above V8 engines are good candidates if a cheaper camshaft solution can be utilized. Also the VH41 and VK45 could be utilized. The VH45 is realy cheap and really available. The VH45 has better heads than the VK by a little bit. The VH45 has slightly larger valves than the VK45. Also comparing the VH to UZ, the VH intake runners are much better as far as flow goes. You can see most of the back of the intake valve on the VH heads where you can barely see the intake valve at all on the UZ head. Then there is all the voodoo about the VH weighing 500 pounds... Maybe if you have all of the emission and other junk on there. I bet the longblock could get down to 350 pounds if you really tried. (The VH valve covers are like 8 pounds each, lol.) As for that crankshaft that you pictured, the notches are not for clearancing, but are a by-product of drilling the angled holes into the rod journals. (note mine are drilled in a straight line through the entire crankshaft, that pictured is a great idea.) Jerminator, Please do some research on the topic. PM me and I'll send you some links to do some basic research before trying to come up with a "hypothetical" dream flat plane V8. Nobody out there that I have seen, even in racing realms, uses a 0% counterweight on a flat plane V8 engine configuration. It would rattle to pieces in a short matter of time. Snap crackle pop. If I were to build a N/A flat plane V8 engine, it would be in the 3.9L-4.1L range with a short stroke and about a 93-95mm bore. Aimed for about a 340-380hp range and rev to 8500-9000rpms. A forced induction version would be around 3.3-3.5 liters. Aimed for the 650-800hp range to be realistic. (100hp per piston is not too heavy for a purpose built engine) Nissan's R92CP with a flat plane V8 was set at about 940hp for races and 1150hp for qualifying. I know there are some pretty crazy videos of its qualifying runs on youtube...
  4. Yes you can run exhaust manifolds in there as there is some room, but not for the stock manifolds. (which you don't want to use, trust me) You can route the exhaust either above the valve cover next to the strut tower or route it inbetween the frame rail and the strut under the fender. (thinking 3" downpipes) You could also run it back under the engine banks if you aren't using power steering or A/C. So there are plenty of options.
  5. Thanks Gollum. 100% counterweight is definitely better as far as bearing wear goes, but in no way will it solve all of the problems with bearing wear. You are always going to have some wear on the bearings with pressures from combustion bushing on the opposing half of the bearing etc... From my observations of flat plane V8 crankshafts, a standard racing counterweight is in the ballpark of 50%. Som people may be confused by the percentages I have been talking about, but it is simply how much mass is on one side of the crankshaft compared with the directly opposite side. 100% counterweight is actually a little bit lighter than a standard cross plane crankshaft of the same stroke. Cross plane crankshafts have 100% counterbalance plus a portion of the connecting rod and piston weight added on as well. The nice thing about the SBF is you can buy a new OEM block from summit for about $500. The flat plane crankshaft that I designed with 100% counterweights actually weighs about the same as the longer stroke cross plane crankshaft that came out of the engine. Reason being that with a shorter stroke you can remove less material inside of the conecting rod journal. With an extra few millimeters of stroke I was able to remove some more weight at the sacrifice of crankshaft durability. (less main-rod bearing journal overlap and less material) Jerminator, lets not get all up in a wad about counterweighing. The SBF has better distributor placement for one. Also a smaller bore which is better for a high reving, small bore, small stroke, V8 Braaaaaaaappppp motor. Now... Single cam V8 vs. DOHC V8. First of all, you will need custom camshafting, which is MUCH cheaper with a single camshaft. Most quad cam V8 heads are good to 7000-8000RPMS with OE parts(with adequate prep work). The problem is that at $250-$400 for custom cams, that can add up quite quickly with 4 cams. With a single cam engine ALA SBC, SBF, etc... you only have one camshaft to buy but there is a lot of other valvetrain gear to survive the high RPMs. NASCAR engines live at 7500-9300 RPMS all day long for 500 miles so that isn't too difficult to come up with a valvetrain that can live at those RPMs. Is there a way to make it feasable to use a DOHC V8 engine and not be out $1200-$2000 in custom ground camshafts? I say yes but I have to punch some numbers first to see if my ideas are even remotely possible.
  6. Once again I'll say: find some books on crankshaft dynamics and read them. There is a lot more going on than you realize. This is off topic but counterweights are necessesary for crankshaft durability and main bearing life. Costworth Subaru crank, probably a CAD image (note the aproximately 30%-50% counterweights with one counterweight per lightened rod pin): It is 18.01lb compared to the stock 20.4lb. Pete, Here are some pics of an OEM Ferrari 355 crankshaft and bottom end during rebuild (Note the MASSIVE main bearing surface area):
  7. Either install the turbos where the battery & master cylinders went(relocating those inside the car) or mount them in the wheelwells behind the front wheels. Those are both good places. Or you can do a traditional setup with twins mounted up front at the top of the engine.
  8. Yes it is organized like a standard 4 cylinder crankshaft. (ala most of the flat plane V8 cranks: Ferrari, TVR, etc...) It is drawn to fit a particular engine..... but could easily be altered to fit any of the above. I still have a lot of work to do on bearing surfaces. There are numerous problems with a flat plane crank that has no counterweights. Mainly with chrankshaft twist and bearing wear factors. Josh817: "have someone build you a bottom end" Umm...how much thinking have you done on that subject? That is going to cost $20,000+ to get a home designed shortblock made. Do you understand how much design work it would be to engineer a complete shortblock? Vibration, block integrity, oiling, crankshaft twist, bank offset, timing chain design, mating to a transmission somehow, etc......... ~~~~~~~~~~~ Crankshaft counterweights are a must. Before talking about not having counterweights and having an uber light weight crankshaft, one should read some books on crankshaft dynamics.
  9. Gollum, how did you decide on counterweight mass? Have you done any stress/distortion math on it? Here is one crank I did... but with a 100% counterweight. (overkill, just to get practice in crank design) Daeron, There is typically about .3mm of side play in the connecting rods. Just as a rough number and varies some...
  10. Here's how mine were: They worked pretty good. They were cheap "baja" headlights that all of the jeep guys have. Plenty rock resistant. It bolted to the stock hood(no cutting) with some fender washers. It was like a rally car when driving the twisties late at night. Just aim them way in (crossing) and you can see everything. Just flip them off in traffic cause its not pleasant to come up on somebody with crosseyed headlights. lol These were brighter than the stock headlights becuase of new wiring too... Action shots... I believe it worked with my 74 bumper too, but I don't exactly remember. This was a long whole back. It looks like it would work. Cleared all of the torsion springs but not the grille.
  11. Ok, The idea of a single crank pin would not be particularly advantageous because all the weight of the crankshaft would be putting tremendous forces on the block at one point in rotation. By going to a single pin with all cylinders on that axis, without full counterweighing, you would munch through your main bearings in a matter of seconds or minutes if you are lucky. If you were to fully counterbalance your single-plane-single-pin crankshaft it would weigh as much or more than a standard cross plane crankshaft, thus eleminating any advantge that you previously had with a standard single plane crankshaft. Think of this example: swing a rope above your head with a 5 pound barbell on the end of the rope. You would be putting extreme stress on your extended arm and you would tire quickly. If somehow you were able to do the same test with a rope in equal and opposite directions with equal weights and spin them, there would be no forces pulling your arm in any particular direction(i.e. not moving your arm in a circle) With a "standard" single plane V8 crankshaft, each crank pin counterbalances the opposing pin, thus reducing your required counterweight by a significant percentage. Then you would have to worry about vibration as BRAAP stated. That is why you would need to fully counterweight the crankshaft, which defeats the purpose.
  12. I'll pull out the pan and hit the creeks in the morning. J/K. You do make a good point there MONZTER. And I was looking at ~.10" weld els.
  13. You can get Illumina struts for about $400+shipping on the web... (JDMwerks on ebay is who I got mine from) Then about $350 for the coilover parts (Jason's garage style...not good for super low ride heights though) Then your welding price on top of that which was free for me. TIG welding is the best for coilovers but MIG will do fine too.
  14. Sorry for no second update yet guys... I'm swamped in classes right now although I have been reading some books on oiling issues and other crank design parameters. OTM
  15. It is an L24E. The rod journals on the crank are different than a standard L6 engine. I don't know about the main jounals...
  16. Well they do call you Wiki... and we all know how reliable that is. Just kidding Tony. lol The principle in a variable throttle body is interesting, but I believe it would be best if you setup a throttle by wire setup with some stepper motors. You could integrate it with boost and throttle depression in your EMS to make max power, low end torque, or economy. Adding more variables has a tendency to make problems though...
  17. "Forrest" had an overbored L26ET that was a 2.7 liter... I believe it was a 1mm overbore. I have seen an L28 made out of a P30 block but you can plan on either using dry sleeves to help reinforce the block or a rather short engine lifespan. L28 blocks aren't THAT hard to find. You just have to be patient. In California L28 motors are practically laying out on the street corners compared to the east coast...
  18. I just had liability on my 260Z and it was $30/month. That was with State Farm...Full coverage was something like $60/month for me but I hadn't had that in forever. 20 year old male, 80k+ miles of driving experience, good student discount, multiple cars, etc... No tickets, no infractions, etc.
  19. I have a straight hood if you want to pay shipping from Atlanta...
  20. Couldn't you use a Datsun/Nissan 720/pickup front diff and remove the extension housing and mount your other axle there with a bolt in stub style R180 center section? Its just an idea that may work.
  21. Thanks guys! I used to drive my 260Z 15 miles each way for two years and by the time I got to my destination I would be drenched in sweat. In the summer it was just the extreme heat with my exhaust .5" from my right foot. In winter I would wear a heavy jacket and sweat inside that while my toes and head froze. It was pretty much misery as far as long drive comfort goes. After 75 miles on the highway at 75mph(3800 RPMs), when I stopped for gas I literally had serious hearing loss for a good 25+ minutes. So I have decided that my daily driver will no longer be my project vehicle/race car. lol I think a 280zxt would be subtle enough for me to not really want to upgrade it-too much, but still be fun to drive. Just clean up the engine bay so it looks nice and be able to have some fun with it. This car seems to be in pretty good shape from what I have seen of it. Fairly fresh L28ET and rebuilt turbo... should be reliable.
  22. Xkne, If your objective is only 200hp, why do all of the custom work? You could get that HP level on an L24 with a stock bottom end and somewhat extensive head work on your head of choice. L motors don't make power with a built bottom end, they need head work and a good flowing intake like Webers or SUs with a free flowing filter. They are handicapped from the low VE of the stock ports. In my opinion the only reason to upgrade the bottom end is when you have reached the extreme limits of a fully built race head and your pistons are being stretched close to their yield stress. I have seen guys build a 3.1 stroker and then go to the dyno and make under 150hp. Then again back in the racing days an L24 made over 250hp... My L26 had a 9.2:1 CR with an open E88 head and I ran 89 octane all day and it NEVER pinged once. I was making in the neighborhood of 130hp. I have seen an L28 at ~11.25:1 CR running on 93 octane and it was a beast of an engine. The car was driven on the highways too and had relatively good gas mileage. I'm not doubting your drive to innovate, just your ($)$$$/hp ratio for 200hp.
  23. Hey guys, In this time of $4.00/gallon gasoline my Frontier has a very high running and insurance cost being an 04 model. I have found an 83 280zxt with 12,000 miles on a rebuilt motor and turbo, swastica wheels, A/C (VERY important in Atlanta), T5 5-speed, T-tops, newer paint, etc... for a pretty good deal. I'd just be keeping the car stock for now, except for removal of smog equipment and cleaning up the motor, interior, etc... Looking for 25+mpg (megasquirt anyone??) and dirt cheap insurance like I had with my S30. (I.E. $30/month) So how many guys here daily drive an S130? BTW I drive about 350-400 miles a week to school. I know driving my S30 like that would pretty much kill me but an S130 would be much different I presume. OTM
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