383 240z Posted December 15, 2002 Share Posted December 15, 2002 OK Here is what I have. A 350 4 bolt with low comp pistons (i think I've yet to pull the heads). A set of warmed over 461 heads with 1.6 roller lifters. and a 750 vac 2ndry holley. the trans is a 700r4 w/ stock stall and 4:11 rears 205/50/15 tyres. I would like to get a new intake&cam combo. If the 350 has dished pistons I have a 327 w/flat tops That I may build instead.But most likely just get new pistons for the 350. I have been looking at the Holley Systemax 218/218 dur @ .050" 268/268 adv 0475" lift 110lobe sep 105lobe center line and a dual plane intake. my other option is the Edelbrock Power Package 204 Int 214 Exh @ .050" .420" Int .442" Exh. If anybody would like to make comments about either combo or to reccomend a different set up please do!! The motor is in my daily driver rx-7 so idle and drivability are my limiting factors I also need to drive this on 89 octane gas. Keith Quote Link to comment Share on other sites More sharing options...
MAYHEM Posted December 15, 2002 Share Posted December 15, 2002 Would you have enough room to to fit a Performer RPM package? sanse the heads. Quote Link to comment Share on other sites More sharing options...
383 240z Posted December 15, 2002 Author Share Posted December 15, 2002 I've got a cowl induction hood sitting on the car now. The car has a stock gm iron intake with a 3/4" spacer and a holley with a 2" air cleaner and I still have about 4" of room. I dont know how high the RPM package sits but I would like to leave enough room for a n02 plate! Keith Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 15, 2002 Share Posted December 15, 2002 The Edelbrock Performer RPM package with 750 CFM & 461 heads but replace the 1.6 lifters with 1.5...RE-EDIT................ The Edelbrock is a little wilder and may be better suited help for the 750 (I thought you were considering the RPM instesd of the Performer plus... The Performer plus would be suited more to a smaller 600 CFM carb) Quote Link to comment Share on other sites More sharing options...
383 240z Posted December 15, 2002 Author Share Posted December 15, 2002 Is there a specific piston I should run with this combo ? I most likly will be using the 350 motor and I think it has dished pistons . I pulled it from a 84 3/4 ton 3+3 4 speed truck. it is a fun ride but as always I need more power !!!! Also should I bump the converter stall??Keith Quote Link to comment Share on other sites More sharing options...
MAYHEM Posted December 15, 2002 Share Posted December 15, 2002 Originally posted by 383 240z:I've got a cowl induction hood sitting on the car now. The car has a stock gm iron intake with a 3/4" spacer and a holley with a 2" air cleaner and I still have about 4" of room. I dont know how high the RPM package sits but I would like to leave enough room for a n02 plate! Keith The Performer RPM is about 3/4 of a inch taller that the Performer. I would go this way. IMO It really woke up my 383.I find that the Edelbrock Performer RPM package is really a win win deal. What compression are you looking at? Can your budget squeeze out aluminum heads? Good point on the rockers. I used both and I found that the 1:5 were fine. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 15, 2002 Share Posted December 15, 2002 Keith I have a performer plus manifold with a Holley 4 barrel with one inch spacer from the top of the cylinder head to the top rim of the Holley is approximately 7 1/4 inches. This measurement might help. Quote Link to comment Share on other sites More sharing options...
MAYHEM Posted December 15, 2002 Share Posted December 15, 2002 Keep it dished for better flame travel,keep around 9.5 w/iron heads and 10.5 with Alum heads,and run IMO Total seal (Gappless Rings). They cost more $$$,but damn there worth it. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 15, 2002 Share Posted December 15, 2002 What is your combustion chamber size on the cylinder heads? Maybe stay to a 10 to 1 compression? Quote Link to comment Share on other sites More sharing options...
383 240z Posted December 15, 2002 Author Share Posted December 15, 2002 Grumpy sold me on the total seal rings a few motors ago!! I love them!! The heads are 76cc I think I have yet to find a cheap burett to check but they look VERY similar to another set of 76cc heads I have here. I don't have the $$ for another set of heads. I plan on pulling the heads soon to see what is in there. Keith Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 15, 2002 Share Posted December 15, 2002 Most likely the question now is to find out what your dished pistons in relation to the 76 cc chambers. and if the pistons are overbore or standard Can you exchange the flatop 327 pistons for the 350 dished considering the 327 and 350 use the 5.7 rod in a later 2.10 journal size but the 327 (3.25) stroke is shorter than the 350 (3.48) stroke. I would agree 9.5 is a good cr Maybe buy some cast hyper pistons Quote Link to comment Share on other sites More sharing options...
MAYHEM Posted December 15, 2002 Share Posted December 15, 2002 KeithBlack, make a good selection of Hypertech pistons. Quote Link to comment Share on other sites More sharing options...
Guest Phil1934 Posted December 15, 2002 Share Posted December 15, 2002 If you decide on the Edelbrock cam just buy it from PAW for $45. They get theirs from the same grinder. Quote Link to comment Share on other sites More sharing options...
383 240z Posted December 15, 2002 Author Share Posted December 15, 2002 OK I just checked the heads they are 64cc I filled them 3cc at a time with a syringe I got from a local drug store. it took a while but I finaly got a number I trusted. Now I really need to find what pistons are in there!! Anybody have a borescope I can borrow?? Keith Quote Link to comment Share on other sites More sharing options...
383 240z Posted December 15, 2002 Author Share Posted December 15, 2002 Oh the hell with it I do have a BRAND NEW 383 sitting here. I just need to pull it apart and clean it up for final assymbly!! but that motor is destined for the Z car. I hate it when I start thinking to much. Keith Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted December 16, 2002 Share Posted December 16, 2002 Get the pistons figured out and you have the makings of a good daily driver. but...... that 383 may deserve a chance at holiday in a another Hybrid for just a trial run..... Quote Link to comment Share on other sites More sharing options...
383 240z Posted December 20, 2002 Author Share Posted December 20, 2002 Is anybody here using the Performer RPM package? I was surprised that nobody spoke up for the systemax setup I had considered the Edelbrok setup before but for some reason I sort of forgot about it. Go figure!! Now I have to wait for the Swap meets to start up in the spring (gotta save some money also) Thanks for the info. Keith Quote Link to comment Share on other sites More sharing options...
pparaska Posted December 21, 2002 Share Posted December 21, 2002 That systemmax cam is lazy - that's a ton of duration between seat and .050" lift. I'd go with a Comp Xtreme or Crane Powermax cam - they typically have about the same "intensity" (less duration difference between seat and .050"), allowing more performance with the same idle characteristics for a 268 adv cam. Even the Magnum Comp Cam has better numbers. I always vote for more cubes now, especially if the engines weigh the same! Quote Link to comment Share on other sites More sharing options...
383 240z Posted December 21, 2002 Author Share Posted December 21, 2002 OK Pete what would you recommend? I plan on driving this thing EVERY day! I just can't accept the low perf numbers this motor has produced. I bought it with out driving it. The car it was in was to unsafe for even me to drive!! but it ran solid and leaked no oil had good vac at idle and was cheap. I bought a holley 750 vac 2ndrys (after your reccomendation I might add) I will be adding a set of 64cc camel hump heads that are fresh(unsure of sping rates) my original intent was to get a matched cam and intake but with everybodies help here I will most likly bolt together a different combo that will work very well!!! Keith Quote Link to comment Share on other sites More sharing options...
pparaska Posted December 22, 2002 Share Posted December 22, 2002 I'd want to know what compression ratio you're running. Have you run a compression test? That'd help. It sounds like you're considering putting in different pistons in the 350. If you put in flat tops with 4cc valve reliefs, a .039" thick composition head gasket, end up with a 0.025" deck height, you'd have about 9.75:1 compression. That might be asking alot for an iron head 350 on 89 octane. A 10 or 14 cc dished piston would give 9.1:1 or 8.8:1 compression. I used pistons from Probe Industries data sheets to come up with compression ratios: http://www.probeindustries.com/Pistons/Pistons_SRS/srs_home.htm With that kind of compression, I'd think a Comp Xtreme XE262H or XE268H would be good. Here are the Dynamic Compression ratios for those 3 static compression ratios and those two cams, installed as suggested by Comp Cams (106 intake centerline): 9.75:1, XE262H: 8.2:1 9.1:1, XE262H: 7.7:1 8.8:1, XE262H: 7.5:1 9.75:1, XE268H: 8.0:1 9.1:1, XE268H: 7.6:1 8.8:1, XE268H: 7.3:1 I'm thinking for 89 octane, you'd want to stay at or below 8:1 dynamic compression. Maybe the 9.75:1 with the XE268H? That might be a bit near the ragged edge though. The 9.1:1 with XE262H would probably be a stump puller. I USED to recommend the 750 vac sec. That's before I was shown the light by Jamie T, Mikelly, and others here. My rear tires hate my double pumper, but I like it much better. The hit when the secondaries come open NOW usually wastes the tires in the lower two gears. With the Quote Link to comment Share on other sites More sharing options...
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