boosted280 Posted January 10, 2012 Share Posted January 10, 2012 I was given a 305 to do with as I pleased. I was wondering what kind of power a built 305 can produce? I want it to be all motor. Quote Link to comment Share on other sites More sharing options...
logan1 Posted January 10, 2012 Share Posted January 10, 2012 A 305 is widely regarded as an excellent boat ancor. Quote Link to comment Share on other sites More sharing options...
surpip Posted January 10, 2012 Share Posted January 10, 2012 No offence but probibly a reason it was givin to you. Heads flow like crap probibly looking at absolute best 350 HP i build one with vortec heads Crane PowerMax H-278 cam/lifter kit RMP air gap 600 CFM carb for a friend of mine. through a T5 dynoed at 298 RWHP put the same parts on a 350 tho and your looking at easily 50-70 more HP Quote Link to comment Share on other sites More sharing options...
boosted280 Posted January 11, 2012 Author Share Posted January 11, 2012 No offense taken. It was given to me because it needs to be rebuilt. But what would a 300 whp zx do in a quarter? Quote Link to comment Share on other sites More sharing options...
surpip Posted January 11, 2012 Share Posted January 11, 2012 Probibly looking at upper 12's/ mid 13's depends on modifications to car/driver skill tires ect. Quote Link to comment Share on other sites More sharing options...
boosted280 Posted January 11, 2012 Author Share Posted January 11, 2012 Well now I still have to decide if I want to part out my current setup or not. Quote Link to comment Share on other sites More sharing options...
surpip Posted January 11, 2012 Share Posted January 11, 2012 take it to a machine shop see if they will give you anything for trade on a 350 what is your current setup? Quote Link to comment Share on other sites More sharing options...
boosted280 Posted January 11, 2012 Author Share Posted January 11, 2012 My current setup is supra 440cc injectors, walbro 225 lph, aeromotive fpr, palnet fuel rail, megasquirt, Fmic with a tial bov, aem wideband, exedy clutch, stock zx turbo, stock zx downpipe opened to a 3" exhaust, greddy profec b spec II, non-egr intake, 240sx throttle body, msd ignition controller, p90 head, turbo piston(was originally n/a), that is most if not all of it, oh and a super hot babe to ride in the passenger seat. I figure I can part this out to cover most of my cost on the swap. Quote Link to comment Share on other sites More sharing options...
surpip Posted January 11, 2012 Share Posted January 11, 2012 Cant hurt to try, sounds like you would almost be going backwards if you did the 305 swap if i where you id look for a decent 383 where are you in TX? Quote Link to comment Share on other sites More sharing options...
boosted280 Posted January 11, 2012 Author Share Posted January 11, 2012 Lol almost except I am only at 210ish whp right now. Quote Link to comment Share on other sites More sharing options...
GOTHALOSISM Posted January 11, 2012 Share Posted January 11, 2012 Sell the hot babe and that will reduce the weight of the car. I would really look for an LT1 or an LSx if I were you. Quote Link to comment Share on other sites More sharing options...
rsicard Posted January 11, 2012 Share Posted January 11, 2012 Purchase a used '96 - '99 Vortec 350 Small Block Chevrolet that was taken out of a wreck. Because it has EFI, the cylinders are usually very good with little wear. Then bore and stroke it to a 383 with a cast steel crank. Forged Rods and SRP 4032 Pistons. Use AFR cylinder heads. Then you have something that has a lot of HP and TQ capability. Build it up yourself so you know exactly what you have. With the right heads, camshaft and induction system, 500+ HP and TQ is within reach. Suggest installing an EFI system. Quote Link to comment Share on other sites More sharing options...
PalmettoZ Posted January 11, 2012 Share Posted January 11, 2012 Is the 305 a crappy motor?? Yes and no. Don't forget that it will produce lots of low end torque, at least 300 ft lbs at 2000 rpm or so. Torque is what accelerates the car in reality. High horsepower numbers are great, but a low end torque V8 that produces only 250 hp will always out accelerate a 6 or 4 cylinder producing lots more hp. Simply because it produces more torque. The higher HP engine will pass it later once the 2 cars are going flat out though. I have a friend who put a set of 305 heads on a 383 block with a comp "tow" cam that would absolutely smoke the tires. It runs out of breath around 4500 rpm of course, but has alot more usable power driving around town. It made for a very torque oriented engine. Tons of fun... Quote Link to comment Share on other sites More sharing options...
Michael Posted January 11, 2012 Share Posted January 11, 2012 (edited) It will take some work to get the 305 to produce 210 hp at the rear wheels. It ought to be possible with the stock heads, but would require some head-work (valve guides/seats, new springs, port-work), intake/carb, exhaust, cam/lifters/springs, and various other bits - assuming that the bottom end is healthy. Even if it is healthy, you will likely need new pistons to achieve a reasonable compression ratio... and that means balancing the rotating assembly, even if you do no machine-work on the block. The point is not that 305 are woefully useless, but that return on investment is inferior to that of a 350-383 class of engine. Since the original poster sounds like a person with preference for the turbo approach, it would likely make sense to persist in the turbo-refinement vein, if the objective is incremental improvements in power. But if the desire is to go from 210 hp to say 350 hp, then indeed the V8 approach becomes attractive. Do however please note that proper building of a V8 is more involved than the Datsun V8 swap itself. Or to rephrase: fear not performing the swap from L6 to V8; instead fear the proper building of the engine. Edited January 12, 2012 by Michael Quote Link to comment Share on other sites More sharing options...
boosted280 Posted January 12, 2012 Author Share Posted January 12, 2012 A 500+ hp engine would be nice but I am really looking for more of a fun weekend car. So from what it sounds like the 305 will do just that. Quote Link to comment Share on other sites More sharing options...
surpip Posted January 12, 2012 Share Posted January 12, 2012 Yes the 305 would get you there, but after the rebuild and parts to make it outperform what you aredy have you might as well get a better foundation to start with. Quote Link to comment Share on other sites More sharing options...
Geking Posted January 13, 2012 Share Posted January 13, 2012 I had the same consideration on 305 or 350. I am so very glad I went for a 350 after comparing my 280z with a friend's late 80s 305 Camaro. Granted the f body is heavier, but still, the 305 is not a sound investment for the effort to swap from the L28 IMHO. To give you an idea, I could easily beat my friends camaro at a light to light game with a stock 280z running a tired motor. The reason the 305 is not liked is because the narrow bore shrouds the valves, making it more difficult for the engine to aspirate. From Wiki: Year hp (kW) lb•ft (N•m) 1976 140 250 w/2bbl. 1977 145 245 w/2bbl. 1978 140 240 w/2bbl. 1978 160 235 w/4bbl. 1979 130 245 w/2bbl. 1979-Ca 125 235 w/2bbl. 1980 155 240 w/4bbl. 1981 150 240 w/4bbl Also, if I am not mistaken, the stock heads on a 305 can not use TPI, but instead uses an intake for chevy's 'crossfire' Essentially two huge injectors at the air filter. Just my vote of not worth it. Quote Link to comment Share on other sites More sharing options...
boosted280 Posted January 13, 2012 Author Share Posted January 13, 2012 I know power wise it would get decimated. I appreciate all the comments from yall. I still do not know what I will do. I do know however my z will get driven this weekend with the current turbo setup. 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.