HarrisonTX Posted January 23, 2006 Share Posted January 23, 2006 Ok, so, as many of you know, im trying to build a 302 (chevy) for my 260z. I have the pistons, crank, and block, the 3 hardest parts to get for a 302. The 302 i have in mind wont be too street friendly so i may go this route for a while http://cgi.ebay.com/ebaymotors/CHEVY-327-330-HP-HIGH-PERFORMANCE-BALANCED-CRATE-ENGINE_W0QQitemZ8030886008QQcategoryZ33615QQrdZ1QQcmdZViewItem Its a 327, with supposedly 330hp. I have seen these on ebay for a long time. The thing that gets me, is he pictures double hump heads. I dont see how this guy has this many 327 blocks, cranks, and double hump heads. how can he afford to sell a 327 for under $2000? What do you guys think. I would call the guy and talk to him personally, but since im in Baghdad, and phone calls are a little pricey, and i dont feel like callin him at night over here, if anyone wants to dig a little deeper, and let me know whats up, lemmi know please. Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted January 23, 2006 Share Posted January 23, 2006 no ware in the description that I can see were double hump fuelie heads mentioned,nor was the cam specs,compression ratio ,4 bolt mains,and type of parts (cast vs forged) youll be getting a remanufactured basic 327, that will probably barely make the advertized flywheel hp but thats IT! I think youll be far better off buying a 4 bolt block from a local machine shop and a set of performance cylinder heads and a cam/lifters for that $2000 you can buy a BRAND NEW 350 with a 3 year warrantee from chevy for about $1700 http://www.sallee-chevrolet.com/frame.html?/sales.html 12499529 - 350/290 HP V8 Crate Engine (youll at least start with a NEW 4 bolt main block) btw read this its worth the effort http://www.rustpuppy.org/chp/Welcome.html Quote Link to comment Share on other sites More sharing options...
HarrisonTX Posted January 23, 2006 Author Share Posted January 23, 2006 Well Grumpy, you advice is not takin lightly. I know about your rep here. I know this can, and will probably turn into a long drawn out disscussion. I want a 327, or a 302. I know 350's can make more power and all this jazz, i just really like short stroke motors. I just dont really know what to do with selecting the motor for this project. I want to spin a 302 to 8 grand, but i know for it to make power up in those high RPMS then i will have to sacrifice low RPM power. I want a built t-5 but if the car is doggy as all hell in low RPMS then the over drive would be pointless. Grumpy i want a 302, i just dont know what to do. then on the other hand, this is going to be a daily driver car, and i cant have some radical cam, that enables high rpms and drive it day to day. So, i could just build a mild 302, but that would be almost like wasting a whole 302, if its gonna be mild, why not just get a crate 350. I am STUCK! Quote Link to comment Share on other sites More sharing options...
Mikelly Posted January 23, 2006 Share Posted January 23, 2006 Turning a T5 at those RPM levels is also gonna be an issue... Seriously do some research. A bone stock T5 tranny is not gonna handle it. Anything custom is gonna be bucks. Talk to Paul Cangialosi at http://www.5speeds.com about what you're facing with regards to those RPMs on that tranny configuration. Mike Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted January 23, 2006 Share Posted January 23, 2006 Build the 302. Wait, do it right, don't rush, don't settle for less than what you want or you'll wish you had waited IMHO. Spinning a 302 8 grand is calling for out of the norm build anyway. Streetable, yes it could be but your going to need relaible valve train so your looking at titanium retainers and roller valve train with 7/16 studs IMO. IMO I'd look for a solid lifter or roller cam that didn't have alot of lift but had more duration like 250 deg at .050 to get you to 8K. In fact I'd probably get a custom ground solid for the budget and run a stud girdle. Get some good flowing heads although the 302 works well with camel iron heads since there isn't that much cfm of air moving, but it will work better with better heads. When you get cams with duration over 240 at .050 the dynamic compression is lower so you can run more static compression. You'll find that the engine will make more power on today's gas if you don't run domed pistons but instead use the 49 cc chambers that can be had on World Products heads, which is what I'd probably use in your application. But if you have domes, then use a diffferent chamber of the new design because they have better flame propagation characteristics than the old GM heads. Domes interfere with flame travel and you'll probably find that more advance timing is needed to obtain good power than you would with no domes. Anyway, I'd bet that 327 is a cast crank, had guide liners in the heads, old wore out valve's, old springs shimmed to 80lbs, cast 327 crank, 2 bolt 350 block, .420 lift hyd cam, new stock rod bolts, and be lucky to see 6K and stay together very long. But that's just my opinion. Quote Link to comment Share on other sites More sharing options...
HarrisonTX Posted January 23, 2006 Author Share Posted January 23, 2006 Turning a T5 at those RPM levels is also gonna be an issue... Seriously do some research. A bone stock T5 tranny is not gonna handle it. Anything custom is gonna be bucks. Talk to Paul Cangialosi at www.5speeds.com about what you're facing with regards to those RPMs on that tranny configuration. Mike I didnt say bonestock t5, i said built t5. Dr. Hunt. So is a roller cam the key to streetablity and high RPMS? I hear roller cams are alot of trouble, and alot of upkeep. I hear you have to adjust the valves alot, there is nothing i hate more than adjusting roller rockers, i would rather change a clutch than adjust rockers. Im aware that RPM = tough valve train. this is gonna be one expensive motor when im done, but it sure will be a bad *** little rocket ship Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted January 23, 2006 Share Posted January 23, 2006 heres what Id build, if I was dead set on a 302 and keeping the costs at the minimum levels...keep in mind the idea here is to get the best results for the least cost, not to spend a great deal of money to get a few extra hp Id start with AFR 180cc heads http://www.airflowresearch.com/ a short block with 11:1 cpr, and Id prefer 6" (H) style rods and FORGED PISTONS are MANDATORY a CRANE 114681 flat tappet solid lifter cam installed retarded 4 degrees http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=114681&lvl=2&prt=5 id run a rocker stud girdle a holley intake HLY-300-110 Holley Keith Dorton Signature Series Intake Manifolds add a 750 holley or demon carb Id run full length 1 5/8" headers (open) since ideally youll have a low restriction tuned exhaust Id use comp cams steel roller rockers (1.5:1 ratio) Id run 4.56 or 4.88:1 rear gears perhaps someone can run you a DD-2000 results ????.........then Id love them to post the results of the exact same combo changing only the stroke to a 3.75" as a 383 would have just so you can see why we build 383s Quote Link to comment Share on other sites More sharing options...
Mikelly Posted January 23, 2006 Share Posted January 23, 2006 I'm with you Grumpy! Of course I OWN a 383! Mike Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted January 23, 2006 Share Posted January 23, 2006 No, I'd go with a custom ground solid that has some duration and not alot of lift, otherwise it'll be hard on valve springs in the long run on the street. I doubt if you could get AFR's on a budget, but if you wait (key here is patience) then it'll happen and you'll be much happier in the long run and I think Grumpy is pretty on with his recommendation on parts. Rollers on the street or solid, both will need valve adjustment. You aren't going to get hydraulics to go 8K cause they won't handle the spring pressure required to have stable valve train at that rpm. So if your not willing to go that route, why don't you shoot for 7K which is more doable IMO even with hydraulic cams. Quote Link to comment Share on other sites More sharing options...
Mikelly Posted January 23, 2006 Share Posted January 23, 2006 Not to mention the abuse that 8Krpms puts on everything involved. If you plan this to be a daily driver, don't plan on a lot of miles without frequent tear downs. If you don't like adjusting lash on valve train parts, you'll defenitely won't like the associated maintenance or cost involved in a high reving SBC. Goodluck! Mike Quote Link to comment Share on other sites More sharing options...
wheelman Posted January 23, 2006 Share Posted January 23, 2006 Grumpy, What do you think of using Vortec heads on this combination? Wheelman Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted January 23, 2006 Share Posted January 23, 2006 vortec heads are designed for low and mid range TORQUE not higher rpm power, will they work, yeah but not nearly as well as the better flowing AFR or similar BRODIX heads that are preferable look, its a compromise, and a 180cc-200cc heads a good match for a 302 spinning 6500rpm-7500rpm, yet not too large for decent power lower in the rpm range vortec AFR holley heres a chart FROM THE BOOK,HOW TO BUILD BIG-INCH CHEVY SMALL BLOCKS with some comon cross sectional port sizes (measured at the smallest part of the ports) ...........................sq inches........port cc edelbrock performer rpm ....1.43.............170 vortec......................1.66.............170 tfs195......................1.93.............195 afr 180.....................1.93.............180 afr 195.....................1.98.............195 afr 210.....................2.05.............210 dart pro 200................2.06.............200 dart pro 215................2.14.............215 brodix track 1 .............2.30.............221 dart pro 1 230..............2.40.............230 edelbrock 23 high port .....2.53.............238 edelbrock 18 deg............2.71.............266 tfs 18 deg..................2.80.............250 as the displacement and rpms increase the ability to fill the cylinders falls off rapidly if the cross sectional area is restricted, this becomes very obvious on a dyno, if the ports too large only the upper rpm range will work effectively, too small and the upper rpms power suffers. BTW theres a 206cc vortec heads that will work read this http://chevyhiperformance.com/techarticles/148_0506_thunder/index1.html Quote Link to comment Share on other sites More sharing options...
HarrisonTX Posted January 24, 2006 Author Share Posted January 24, 2006 So, in that list of parts, what would the low RPM be like? im not looking for much power down there, im just worried about having to set the idle at 1500 rpm. I know DD will help me out, i need to buy that program Quote Link to comment Share on other sites More sharing options...
boodlefoof Posted January 24, 2006 Share Posted January 24, 2006 Or, if you're going for a short stroke, high-rev motor... build a 350 the alternative way... use a 400 block and a 3.25'' stroke crank. Check out the article "The Small Block Chevy Should Have Built." It is available online in the AFR article archive at http://www.airflowresearch.com/ It is the second to last article in the small block chevy category. Quote Link to comment Share on other sites More sharing options...
A. G. Olphart Posted January 24, 2006 Share Posted January 24, 2006 A little research on high RPM valve springs and their life span may be in order. (Unlike Grumpy, I don't have a link for you). There is a reason that racers change springs a lot. If you don't like adjusting valves, you really won't like changing springs. Edit: This is only a part of what Mikelly referred to. . Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted January 25, 2006 Share Posted January 25, 2006 can someone with the computer skills necessary PLEASE.. PLEASE ! post the picture of the power curve for both the 302 and 383 using the parts just as I listed them above???...damn I wish I could do it!.....LOOK I don,t throw random parts together, theres a reason those parts were sellected " Id start with AFR 180cc heads http://www.airflowresearch.com/ a short block with 11:1 cpr, and Id prefer 6" (H) style rods and FORGED PISTONS are MANDATORY a CRANE 114681 flat tappet solid lifter cam installed retarded 4 degrees http://www.cranecams.com/?show=browseParts&action=partSpec&partNumber=114681&lvl=2&prt=5 id run a rocker stud girdle a holley intake HLY-300-110 Holley Keith Dorton Signature Series Intake Manifolds add a 750 holley or demon carb Id run full length 1 5/8" headers (open) since ideally youll have a low restriction tuned exhaust Id use comp cams steel roller rockers (1.5:1 ratio) Id run 4.56 or 4.88:1 rear gears perhaps someone can run you a DD-2000 results ????.........then Id love them to post the results of the exact same combo changing only the stroke to a 3.75" as a 383 would have just so you can see why we build 383s" Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted January 25, 2006 Share Posted January 25, 2006 I don't know how to do that and the airflow files I have are for the AFR 210. But with the 302 your looking at 505HP at 7500rpm peak, and 409 tq at 5500. The 383 with the same parts is 519HP at 6500 and 476 TQ at 5000. Both are with long tube headers with mufflers, 750 carb and single plane manifold. I'm sure that the AFR180's will be down on that power and TQ somewhat. Quote Link to comment Share on other sites More sharing options...
beren Posted January 25, 2006 Share Posted January 25, 2006 Or' date=' if you're going for a short stroke, high-rev motor... build a 350 the alternative way... use a 400 block and a 3.25'' stroke crank. Check out the article "The Small Block Chevy Should Have Built." It is available online in the AFR article archive at http://www.airflowresearch.com/ It is the second to last article in the small block chevy category. I've read that before... it makes my jaw drop... I have never built a SBC before, so my question is, how much of the theory presented in that article is transferrable to the LSx family? Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted January 25, 2006 Share Posted January 25, 2006 "I'm sure that the AFR180's will be down on that power and TQ somewhat." those numbers are close to what I got useing EA PRO but surprizingly the 180 cc heads HELPED the 302s power curve and only HURT/RESTRICTED the 383 slightly,(6% lower rpm port stall on the 180cc vs the 210cc) keep in mind the low lift flow is better and runner velocities higher on the smaller ports, and flow potential above .550 lift is meaningless as the valves never reach that lift, plus everytime the valves open they flow at .200-.0300-.0400-.0500 but don,t have the slight (6%)lag in flow the larger port would have at low rpms, I also matched the combo to 1 5/8" headers and cam LSA to improve mid rpm flow/scavaging so the actual flow would be better on the smaller heads in that range also keep in mind the 383 with its aproximately 27% larger displacement reaches the same port flow velocities at 27% lower rpms Quote Link to comment Share on other sites More sharing options...
boodlefoof Posted January 25, 2006 Share Posted January 25, 2006 Beren, I'm sure the principles hold up in the LS engines. I don't know, however, if the quench effect is as pronounced though with the (presumably) more efficent chamber design those engines use. The rod/stroke ratio also tends to be shorter in the LS engines. That means faster instantaneous piston accelleration, which typically means more low-rpm airflow. In older engines, the increased rod angle increased stress on parts, and some thought that the benefits of a long rod outweighed the air pumping factor. Perhaps with the LS engines the parts are of better quality and this isn't a concern. I don't know... but it seems to work. Quote Link to comment Share on other sites More sharing options...
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