Guest nicodemus Posted March 31, 2004 Share Posted March 31, 2004 Well, I used to be a strait 6 guy, through and through, I love em, they are bullet proof and can make alot of power with alot of money. I don't have alot of money. I think I am ready to cross the line, I have a '71z, built in 70. It has a 2.9l stroker (l24) tripple mikunis and the lot, but its finniky, and peaky. I want more so im thinking v8, if I go this route I want to build a chevy 302, my dad had one, my girlfriends dad had one, and they where homemade. they recomend them highly, but neither are readily available for questioning. First off, I will be using a 327 block, 289 crank and heads. Am I wrong (not a v8 guy yet don't hit me). I know going 350 is probobally the cheapest, but what am I going to have to do structerally to the car to be able to handle the weight/power? beef up the frame rails, add a roll cage? Any info you have would be much appreciated. Quote Link to comment Share on other sites More sharing options...
rustorbust Posted March 31, 2004 Share Posted March 31, 2004 283 is the crank and i wouldnt use 283 heads. Use somthing a little more modern. James B. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted March 31, 2004 Share Posted March 31, 2004 Man, what is it with guys named nic and 302's? Actually your structural requirements are no different for a 302 than a 350. Depending on how you build it the 302 won't be giving up that much HP compared to the 350. The thing to keep in mind is you have the structurally weakest Z made. The later ones flexed considerably less. So my suggestion is to spend a few weekends searching the chassis section reading old posts. This question is a common one. There are lots of different opinions on how it should be done so reading old posts will help you narrow down what you want to do. Quote Link to comment Share on other sites More sharing options...
jap tin Posted March 31, 2004 Share Posted March 31, 2004 Use a early 327 small journal block and a small journal 283 crank. 4.00 bore with a 3.00 stroke makes a 302 or a 301.59 . If you have to bore the block .030 you wind up with a 306. Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted March 31, 2004 Share Posted March 31, 2004 sure run this thru dd-2000 a crane 114681 solid flat tappet cam 1.6 ratio roller rockers afr 195cc heads 10.7:1 cpr 1 5/8" full length headers with merge collectors and (an (X) just as close to the collectors as you can get it) a EDELBROCK SY1 intake (its entered as a tunnel ram on the software)(youll need to find one on EBAY)they are designed for a single carb and to fit under the 69 Z28 hood and give tunnel ram flow with more mid range torque on a 302,if you can,t find one the offy cross ram is still in production and a good substitute available from these guys last time I checked http://www.pawengineparts.com/cataloginfo.html and yeah they were available with either a single or dual carb top last time I checked but almost everyone goes with the dual 4v carbs yes you could just keep things simple, and cheaper, and use a edelbrock vic,JR single plane intake but youll loose some mid range torque if you do! and a 800 vac secondary holley carb use 4.56 -4.88 rear gears so youll stay between 4500rpm and 7500rpm racing now copy the hp tq curve numbers and change the stroke to 3.875" and the bore to 4.060" on the dd-2000, now look at the tq curve,you should notice WHY I sugguest a stroker combo is the better choice for a street car........notice the rpm level where the power is and the much more useable torque curve for street use, now with the stroker 3.73-4.11 gears are a better match and the chance of getting into valve float is greatly reduced Quote Link to comment Share on other sites More sharing options...
Guest JAMIE T Posted March 31, 2004 Share Posted March 31, 2004 I like a free revving engine. Then again, I've been drinking black and tans this evening, so please excuse me if I spell poorly. As Jap Tin said(have you seen his freakin car BTW?) , small journal 327 block, 283 crank. light rods and pistons, and an aluminum flywheel. FWIW, if you put an automatic behind that 302, you'd be a punk. And, I will bust on you day and night. If you've ever driven a car that doesn't make power until 5000 RPM, it is a rush fo a feeling. My buddies VTEC headed CRX gets real fun around 5K. It starts spinning the tires about there. The cross ram ram would b totally bitchen. I think Pete got one for his 406. The Offy one is the only one anyone could afford. The Edelbrock one is out of production and getting expensive(Pete got a good deal on his). He is using throttle bodies on his, EFI. I get a boner just thinking about it. BUT THEN AGAIN, as Grumpyvette suggested, Big cubic inches rule on the street. They are easier on valvetrain, last longer, and make power in lower RPM's were it counts. Quote Link to comment Share on other sites More sharing options...
Guest Nic-Rebel450CA Posted April 1, 2004 Share Posted April 1, 2004 Man' date=' what is it with guys named nic and 302's?[/quote'] Hahaha, and here I come to comment. In my opinion, the 302 is a good choice for the Z, but is not a good money-saver engine. Yes, you will have to beef up the Z just as much, especially since it is an early 240. You may even have to beef it up more if you plan to do some high RPM shifts (remember, torque multiplies). If you are set on building a 302, read some of my old posts and feel free to ask me any questions. I will be building a 302 out of a 350 block, bearing spacers, 283 crank, and 4.0" bore heads. If you use 283 heads, you will be ruining the potential of a 302, and might as well build a 283. The whole benefit of building a 302 as opposed to a 283 is the ability to use mainstream heads. Basically, the opinion of everyone you talk to is going to be that you better have some really good reasons to build a 302 instead of a 327 or 350. It's going to be more work, more money, and more maintenance. Just as a side note, a 302 is not an engine that "doesnt make power until 5000 RPM". Play with desktop dyno. With the right combination a 302 will make plenty of power before 5000, and then excellent power above 5000. My planned combo should be about 350HP at the crank, with about 270 ft/lbs of torque as low as 2400 RPM. Quote Link to comment Share on other sites More sharing options...
Guest 77vegasz Posted April 2, 2004 Share Posted April 2, 2004 The "camel hump" heads, I believe 461 casting were used on the 302. You can find a pair on E-bay, but be prepared for big shipping charge, and then machine shop work to freshen them up.The good news is, you can use them on any small block, so once you recondition them, youll have them around. I am not sure of the cam used in the original 302, but Crane makes a line of "blueprinted muscle car" cams. Amoung them is the excellent 350hp 327 cam. I run this in my car. It has a nice little lope to the idle, and makes power between 2000-6000 rpm. Jon Quote Link to comment Share on other sites More sharing options...
Guest Nic-Rebel450CA Posted April 2, 2004 Share Posted April 2, 2004 I wouldnt run a lopey 327 cam in a 302. Believe it or not, the more mild the cam, the better the 302 will run. If you run more duration or lift then you will drastically lose bottom end performance. Nicodemus, what is your intended use and what are your HP and torque goals? Up to a certain point, the 302 can make the same power as a 327, 350, or 383 and just as easily. It just depends on how much power you want. If you want more than 350 HP at the crank, then the 302 is probably not going to be the right choice. Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted April 2, 2004 Share Posted April 2, 2004 the 461 heads in stock config flow 216/137 cfm they are junk by todays standards its basically the same casting and flow as the 462 heads part # 3849346 Mech. 254/254 dur .485"/.485" lift 114 LSA 327/365HP & Z-28 302 cam is 34 year old technology, again junk by todays standards horsepower is basically gained from effectively filling and burning the greatest amount of fuel/air mix at the highest compression you can to make the max cylinder pressure you can within the limits of rpm,displacement and fuel quality todays better designs in cylinder heads allow lower ignition advance, faster flame fronts, less detonation,and wider torque curves look heres modern vortec truck heads now the vortec heads are better but look what good heads flow those modern designed heads have about a 18% better flow potential over most of the rpm range, thats worth at least another 40-50 additional hp I can tell you from building several 301-327 cid engines in years past that the crane 114681 solid lifter cam thats got less duration and more lift significantly out performs the original Z28 cam ESPECIALLY when matched too the better heads the ONLY reason they ran 302 displacement engines was the 5 liter displacement limit in trans am racing, anyone without a displacement limit would have used a 377 or 406 as they put out a good deal more useful torque/horspower curve if you have a DD-2000 program play with the specs and see for yourself Quote Link to comment Share on other sites More sharing options...
Guest nicodemus Posted April 5, 2004 Share Posted April 5, 2004 I would like to put 300hp to the pavement, so 350 to the crank would be plenty. the reason I chose this set up is becuase I hear that they are more rev happy than the 327 and 350. they like being in the higher rpm and they rev faster, but one of the admitted appealing aspects of the sbc z is the drivability, where I would imagine the 350 edges out. My friend has a 400ci sbc and the 350crank making it a 377 stroker if I can remember righ. The crank is helping that beast rev, and like i said i do Like how the L6's rev, but id want a bit mor torque. I would be using it for autocross and the weekend/possibly daily driver, and after tuning my z up after the first post, i realize I will probobally have to use a 350, because the set up I have really moves, im sitting in the 13's right now, but it has to be in exactly the right gear at the right time and if you miss a heel/toe, t rear end snaps a bit. I don't want to have to do alot of extensive frame work, but I have been wanting to do some whichever way I choose to go just becase it is a slightly flexible chassis. Oh, what about some other combo's like a 350 block with 283 crank? 327 crank? or coorosponding heads? Quote Link to comment Share on other sites More sharing options...
Guest Nic-Rebel450CA Posted April 5, 2004 Share Posted April 5, 2004 Oh, what about some other combo's like a 350 block with 283 crank? 327 crank? or coorosponding heads? A 350 block with a 283 crank makes the 302. A 350 block with a 327 crank makes a 327. A 327 may be a good choice for you, you will get a lot of the revability aspects you are looking for, and a 327 will make that power very easily. Talk to HeavyZ about his setup. It rocks! Quote Link to comment Share on other sites More sharing options...
Guest 77vegasz Posted April 5, 2004 Share Posted April 5, 2004 I run a 327 bored .040 over, (necessary as block was worn) flat top pistons, 461 camel hump heads with Crane roller rockers and the cane blueprinted 350hp-327 cam. I run a high rise single plane intake with a holley 650, block huggers into 2 1/2 duals feeding side pipes. The car is hard to keep hooked up on a hard launch, PLENTY of torque. It is very drivable under normal conditions. I am still working out the details, but this combination Rocks. Desktop dyno estimate the hoorse power in the 370 range at 6000 rpm. Any more hp than this would be fairly unusable unless you do some mods to keep it to the ground. Jon Quote Link to comment Share on other sites More sharing options...
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