a6t8vw Posted February 15, 2007 Share Posted February 15, 2007 hello there, im almost finished with my swap, 280z, fresh .040 over mid 70's sbc, 8.5;1 compression, herbert torque cam, weiend X-cerator single plane intake manifold, TCI th-350, summit 2k stall converter, mallory dizzy and 6AL box, march serp. underdrive pulleys, alum driveshaft, stock rear end, 265 tire.... I really have no idea what to expect and/or if my combo of parts is even going to work... any thoughts? andy Quote Link to comment Share on other sites More sharing options...
280zwitha383 Posted February 15, 2007 Share Posted February 15, 2007 8.5;1 compression, herbert torque cam, weiend X-cerator single plane intake manifold Single plane = higher end power aka horsepower Torque cam = low end power 8.5:1 = no power Put the three together and you have a mismatched setup and the Man above only knows what it will do. In such a light car you may never realize the shortcomings of the engine and I hope this is the case. What kind of heads are you running? Quote Link to comment Share on other sites More sharing options...
Corzette Posted February 15, 2007 Share Posted February 15, 2007 hello there, im almost finished with my swap, 280z, fresh .040 over mid 70's sbc, 8.5;1 compression, herbert torque cam, weiend X-cerator single plane intake manifold, TCI th-350, summit 2k stall converter, mallory dizzy and 6AL box, march serp. underdrive pulleys, alum driveshaft, stock rear end, 265 tire.... I really have no idea what to expect and/or if my combo of parts is even going to work... any thoughts? andy Hmmm I dont want to sound negative here but here is my 2 cents worth from experience. I dont know what your lift and cam specs are but I do know that with the single plane intake, a 2000 stall and 8 to 1 compression it will probably be a dog off the line. The single best improvement I can see you making is simply replacing the intake to a dual plane. This should pickup your lower end quit a bit. Ofcourse then a cam change may be in order as well as converter. I picked up 5 tenths just going from a 2800 stall to a 3500 stall on my latest build. My first build I went from a 14.3 to a 13.7 in the quarter with stock heads just by changing the cam. I was running a Comp 292 magnum and changed to a Comp 262 flat tappet. Made a big differece. As 383 said matching components is the most important thing when looking for max performance. I would say get all your specs together and start playing with them in Dyno 2000 or something similiar to get the best bang for what your working with. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted February 15, 2007 Share Posted February 15, 2007 8.5:1 Compression? Sounds like a forced induction candidate. Put a blower on that beast. Quote Link to comment Share on other sites More sharing options...
A. G. Olphart Posted February 15, 2007 Share Posted February 15, 2007 With a dual plane manifold, this sounds like a great 87 octane street cruiser. If you are running forged pistons and decide you want more poop, Pop's suggestion has merit. PS: Since you've got it built-- drive it! If it boils the tires with the single plane, you're done. <> Quote Link to comment Share on other sites More sharing options...
DavyZ Posted February 15, 2007 Share Posted February 15, 2007 hello there, im almost finished with my swap, 280z, fresh .040 over mid 70's sbc, 8.5;1 compression, herbert torque cam, weiend X-cerator single plane intake manifold, TCI th-350, summit 2k stall converter, mallory dizzy and 6AL box, march serp. underdrive pulleys, alum driveshaft, stock rear end, 265 tire.... I really have no idea what to expect and/or if my combo of parts is even going to work... any thoughts? andy Andy, researching engine combinations before putting it together is key. I'm assuming your heads are stock as is the compression. The "torque cam" is probably made for low end/low rpm power, which is fine, but the intake is meant for high rpm use. You are better off with a dual plane, like a Performer manifold. Stock Chevy is in the 200 to 230 hp range. Since we don't know your cam specs, its hard to say what you'll end up with. If you change the intake, the torque will be pretty good and you'll have snappy, but not overwhelming, performance from your car. I'm thinking you'll have 275 to 300 hp max and maybe that much torque if you change the manifold. Someone with DD can run the numbers and give you a better estimate, but we need more info. EDIT: upon further thought, your combo is mismatched and may make the same or less power than the stock Chevy engine. The ball buster is your intake with all the other parts you have. Does this make sense? Davy Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted February 15, 2007 Share Posted February 15, 2007 Im forced to aggree that a good dual plane LIKE a HOLLEY or EDELBROCK DUAL PLANE would help here. you might want to pick up a copy of this, its fun to play with, answers or at least gives some idea as to what youll expect http://www.autorepairmanuals.biz/site/573683/product/186010 you really should get these books and read them before going any further, it will help a good deal, while only the basic info is presented it still makes for a good knowledge base, and referance buy and watch this cd and read this first http://www.themotorbookstore.com/resmchstvi.html HOW TO BUILD THE SMALL BLOCK CHEVEROLET by LARRY ATHERTON& LARRY SCHREIB HOW TO BUILD MAX PERFORMANCE CHEVY SMALL BLOCKS ON A BUDGET by DAVID VIZARD JOHN LINGENFELTER on modifying small-block chevy engines SMOKEY YUNICK,S POWER SECRETS get the CD on engine assembly,and the books I listed , its the best money youll ever spend! know what your trying to do, and how and why the engine goes together the way it does will prevent hundreds of dollars in potential mistakes you can get EVERYTHING from either http://www.themotorbookstore.com/resmchstvi.html or http://amazon.com/s/ref=nb_ss_gw/102-5007616-6964908?url=search-alias%3Daps&field-keywords=sbc+engines&Go.x=9&Go.y=9 parts sources http://www.chevelles.com/forums/showthread.php?t=161485 info you need http://www.chevytalk.org/fusionbb/showtopic.php?tid/131229/ http://www.airflowresearch.com/articles.php#SBC http://www.ryanscarpage.50megs.com/combos1.html Quote Link to comment Share on other sites More sharing options...
m1noel Posted February 15, 2007 Share Posted February 15, 2007 Your car is way too beautiful to not take the guys advice and do a bunch of research before you just slap parts on an engine and throw it in... MIke Quote Link to comment Share on other sites More sharing options...
280zwitha383 Posted February 16, 2007 Share Posted February 16, 2007 How far are you along with this engine? I would definitely agree about putting a dual plane intake. I'm not really sure that you would ever benefit too much from a single plane intake if in fact you did have stock heads. Also, torque cams are for 4x4 and RV's. You want more hp in these cars because you're going to redline rather quickly and you will predominantly be in a higher power band than a torque cam will offer. You always want to build you engine to perform best in the rpm range that it will spend the most time in. If I were you I would change the pistons and or heads to get you around 9.5:1 compression. Change the cam to say something with atleast .450 lift and atleast 270 duration. This is of course for a very mild build. I would also switch to the trusty performer air gap intake (rpm will do fine if you want to save a few $). You WILL make better power across the board because it will be much better matched. Quote Link to comment Share on other sites More sharing options...
280zwitha383 Posted February 16, 2007 Share Posted February 16, 2007 BTW, that really is a pretty car you have. Quote Link to comment Share on other sites More sharing options...
Michael Posted February 16, 2007 Share Posted February 16, 2007 I’m going to disagree here; this guy’s combo isn’t that bad! Comparing the specs, it is actually not too different from the Goodwrench 260 hp "stock replacement" engine. Most of us run <9.5 compression with cast iron heads; will one point of compression make that much of a difference? For the technically minded, consider how one point of compression affects the DCR with the valve closing profile on the typical flat-tappet hydraulic cam. BTW the "torque cam" should be good for maintaining cylinder pressure with the relatively low static CR. Yes, the intake manifold is mismatched, and maybe costs 30 ft-lbs of torque at 2000 rpm; maybe more if the carb is too big; even more if the manifold’s runners match poorly with the intake ports of the heads. But it’s not like it is magically turning a 500 hp engine into a 75 hp engine. Even with “only†200 hp and perhaps 250 ft-lb at the crank (160/200 at the rear wheels, give or take) this should be a reasonably enjoyable car to drive, provided that the TUNING is right! I’d not worry about swapping parts, or second-guessing oneself about mismatched this or that, and instead would focus on good, reliable timing and fuel delivery. Make sure that the rings are holding compression, that there are no chunks of metal in the oil pan, that the carb isn’t puking fuel and that the plugs are not fouling. The rest, I think, is of secondary importance for the time being. Quote Link to comment Share on other sites More sharing options...
280zwitha383 Posted February 16, 2007 Share Posted February 16, 2007 I agree. I was just saying if it was ME (and probably if the thing wasn't already built). If I already had the engine and it was complete I would stil change the intake and call it good (enough). Tuning an engine that he is describing might be a bit of a challenge in itself depending on his experience because it just might not run that great at lower rpms. The power to weight will mask these problems more than likely however. Quote Link to comment Share on other sites More sharing options...
icewtr Posted February 16, 2007 Share Posted February 16, 2007 Ok, I have my 2 cents to add..lol. My first motor in my 70 z was a 60 over 350 WITH 8.5 Compression junk heads from an 84 camaro. They had 185/150 valves. I had a 280h cam that was 480 lift on both intake and exhaust and 280 duration and no stall with a 700r4 trans 3.36 gears with a 750 holley carb and a victor jr single plane intake and ran 13.00 AT 105 MPH with a 100 shot of nitrous ran 12.03 at 118mph. So just try what ya have and if ya are looking for a monster of a motor or crazy power then go from what ya have learned the first time around. The car was a blast to drive on the street that way. Quote Link to comment Share on other sites More sharing options...
280zwitha383 Posted February 16, 2007 Share Posted February 16, 2007 That is slightly impressive. However, the only thing that you really have in common with him is the compression. You have a far superior cam (IMO) and even if you had a single plane it would be somewhat matched with the cam. Quote Link to comment Share on other sites More sharing options...
73ZCAR Posted February 16, 2007 Share Posted February 16, 2007 I almost hate to say it but.... That motor sounds like a perfect candidate for something like that Holley Systemax setup. Yank the cam and manifold and sell em on E-bay Maybe switch the converter to a 3500/stall. What do you guys think? Mike. Very nice looking car by the way. Quote Link to comment Share on other sites More sharing options...
a6t8vw Posted February 16, 2007 Author Share Posted February 16, 2007 thanks for the replies, unfortunately i bought the motor as is.. i wish i had the cam spec's but was told it has "slight lope" and higher lift than one would think for a tq cam.. but i do agree that the intake need to be changed to a 180 deg. dual plane. What im regreting is buying the th-350. Ill be on the lookout for a 5 or 6 speed manual. Have you guys seen this n20 manifold? looks really nice http://www.noswizard.com/images//products/spider%20lg.jpg BTW: how much nitrous can a stockish low compression sbc take? 100hp? Quote Link to comment Share on other sites More sharing options...
icewtr Posted February 16, 2007 Share Posted February 16, 2007 It is not a question of how much it will take... it is how well it is tuned that makes the biggest deal.. i have had friends blow motors due to stupid things like not checking bottle pressure or fuel .. hot rod magazine did a test on this and they had 250hp on a cast piston old junk 350 chevy till it blew appart.. my $400. rebuilt 8.5 cast piston motor got punished after i got the new 383 just to see what it would take and leaving the line on a 150 shot at 1000rpm didn't even melt a plug the car just got faster so i gave up... Quote Link to comment Share on other sites More sharing options...
DavyZ Posted February 18, 2007 Share Posted February 18, 2007 Andy, again, the only thing mismatched is the intake. You can get an Edelbrock dual plane/Performer or Chinese copy (Professional Products) for relatively cheap on ebay. Just keep the motor 'as is' and change out the intake. That way, what you already have will be maximized for what it is. You'll actually enjoy your motor and car a lot after that. As far as the tranny is concerned, you can always use it, but just don't go cruising the freeways much. Davy Quote Link to comment Share on other sites More sharing options...
a6t8vw Posted February 19, 2007 Author Share Posted February 19, 2007 thank davy, grumpy, and the others that replied... and grumpy im going to buy that dvd video thanks. andy Edit: hey davy, performer or performer RPM? Quote Link to comment Share on other sites More sharing options...
280zwitha383 Posted February 19, 2007 Share Posted February 19, 2007 I'm not davy but AIR GAP! Quote Link to comment Share on other sites More sharing options...
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