vega Posted June 8, 2012 Share Posted June 8, 2012 (edited) 195cc intake runner, 64cc combustion chamber, aluminum, 2.02, and 1.60 valves Superflow sf 600 flow com air speed: 380-400FT, 375-410SC Intake; (.1)66 (.2)141 (.3)200 (.4)242 (.5)270 (.6)265 (.7)268 Exhaust; (.1)55 (.2)107 (.3)139 (.4)167 (.5)192 (.6)209 2500lb car 245/50r16 street tires rated at 320aa by firestone (I don't really need tq the car is very light and I am limited on tire) 1987 700r4 trans 3.545 rear gear ratio 10.25:1 compression chev 327 40 over now may end up 60 over soon 1.6:1 rocker ratio Looking for a solid flat tappet. I'm looking to have a very WIDE rpm range, as much as possible. Comp claims the old duntov 30-30 is between 2300-6900. I'm talking that kind of wide. The issue with that cam is that the one they sell it for a 350, in a 327 that would bump my rpm past what I want it to be. The 30-30 does suck (compared to modern cam profiles), I am just pointing out that a wide powerband in a solid flat tappet can be done. Also when I was saying the difference between a 350 and a 327. The small crank throw will up the rpm a bit. Instead of being at 2300 it would be like 2500-2600, and instead of being 6900 it would be like 7200-7300. That is too peaky for me. 2300 to 6900 would be perfect if it was rated for the 327. When comp rates those numbers they are all done with a 350 base. Not a 3.25 but a 3.48 crank. I'm looking for a 6700-7000 peak rpm, with it coming in as low as I can get it at. One thing I have heard and read a lot of debate about is the fact that the 327 doesn't sit at top dead center for very long so a wide lsa (about a 112-114) would be beneficial. Also it would kill the tq down low. The other end of this opinion is that one could do a 110 lsa and advance it quite a bit. I don't honestly know what would be best. Some help/thoughts/advice would be great. The car is intended for the road course at BIR in MN. Both the outer longer track and shorter center track. http://www.brainerdraceway.com/ It looks like 1st gear is just to get going and 2nd gear should be about 33 mph at 2500 rpm and will be 80mph at 6000rpm. 3rd will go from 55mph @ 2500rpm to 130 @ 6000rpm or 140 @ 6500 rpm so 3rd should be a great gear for most of the high speed sections. 2nd should be enough for any tight stuff. Overdrive is 200mph + so that's good for a bit of extra pull down a straight if I'm able to go faster than 140mph before braking for the turn. Looking at the Brainerd track it looks like a lot of high speed corners and long straightaways without too many tight corners. I have wide gearing so this should suit the track well but it means I need a wide powerband as well. Help and advise or a point in the right direction would be great. Edited June 9, 2012 by vega Quote Link to comment Share on other sites More sharing options...
roger280zx Posted June 8, 2012 Share Posted June 8, 2012 Call Isky, tell them your setup and goals. Quote Link to comment Share on other sites More sharing options...
vega Posted June 8, 2012 Author Share Posted June 8, 2012 Called them. I've called 8 different cam companies. There are too many different opinions. one guys says 110 lsa, another says 114, another guy says 108 even. Then one guy said 236 intake, another says 242, another says 254. One guy says 247 exhaust, another says 254, another says 269. Seriously way too many opinions. I want an educated straight forward answer. Quote Link to comment Share on other sites More sharing options...
Dat260 Posted June 8, 2012 Share Posted June 8, 2012 Talk to Grumpy, he's the wizzard! Quote Link to comment Share on other sites More sharing options...
vega Posted June 8, 2012 Author Share Posted June 8, 2012 Talk to Grumpy, he's the wizzard! Grumpy? Quote Link to comment Share on other sites More sharing options...
emeraldlion Posted June 8, 2012 Share Posted June 8, 2012 Member grumpyvette. He has a website, Grumpy's performance garage. His site has a forum with TONS of great info from fuel to exhaust, cams, heads etc. I highly suggest going to the site if you haven't just for fun. I am sure he will chime in for you. He will also appreciate the specific info you have provided. Quote Link to comment Share on other sites More sharing options...
vega Posted June 8, 2012 Author Share Posted June 8, 2012 Neat, I hope to hear from him. I will check out the site. Quote Link to comment Share on other sites More sharing options...
vega Posted June 9, 2012 Author Share Posted June 9, 2012 Posted this in that forum. Looks like a great page! Thank you for the tip! Quote Link to comment Share on other sites More sharing options...
vega Posted June 9, 2012 Author Share Posted June 9, 2012 Anyone else aside grumpyvette have ideas? Quote Link to comment Share on other sites More sharing options...
Scarab73 Posted June 12, 2012 Share Posted June 12, 2012 195cc intake runner, 64cc combustion chamber, aluminum, 2.02, and 1.60 valves Superflow sf 600 flow com air speed: 380-400FT, 375-410SC Intake; (.1)66 (.2)141 (.3)200 (.4)242 (.5)270 (.6)265 (.7)268 Exhaust; (.1)55 (.2)107 (.3)139 (.4)167 (.5)192 (.6)209 2500lb car 245/50r16 street tires rated at 320aa by firestone (I don't really need tq the car is very light and I am limited on tire) 1987 700r4 trans 3.545 rear gear ratio 10.25:1 compression chev 327 40 over now may end up 60 over soon 1.6:1 rocker ratio Looking for a solid flat tappet. I'm looking to have a very WIDE rpm range, as much as possible. Comp claims the old duntov 30-30 is between 2300-6900. I'm talking that kind of wide. The issue with that cam is that the one they sell it for a 350, in a 327 that would bump my rpm past what I want it to be. The 30-30 does suck (compared to modern cam profiles), I am just pointing out that a wide powerband in a solid flat tappet can be done. Also when I was saying the difference between a 350 and a 327. The small crank throw will up the rpm a bit. Instead of being at 2300 it would be like 2500-2600, and instead of being 6900 it would be like 7200-7300. That is too peaky for me. 2300 to 6900 would be perfect if it was rated for the 327. When comp rates those numbers they are all done with a 350 base. Not a 3.25 but a 3.48 crank. I'm looking for a 6700-7000 peak rpm, with it coming in as low as I can get it at. One thing I have heard and read a lot of debate about is the fact that the 327 doesn't sit at top dead center for very long so a wide lsa (about a 112-114) would be beneficial. Also it would kill the tq down low. The other end of this opinion is that one could do a 110 lsa and advance it quite a bit. I don't honestly know what would be best. Some help/thoughts/advice would be great. The car is intended for the road course at BIR in MN. Both the outer longer track and shorter center track. http://www.brainerdraceway.com/ It looks like 1st gear is just to get going and 2nd gear should be about 33 mph at 2500 rpm and will be 80mph at 6000rpm. 3rd will go from 55mph @ 2500rpm to 130 @ 6000rpm or 140 @ 6500 rpm so 3rd should be a great gear for most of the high speed sections. 2nd should be enough for any tight stuff. Overdrive is 200mph + so that's good for a bit of extra pull down a straight if I'm able to go faster than 140mph before braking for the turn. Looking at the Brainerd track it looks like a lot of high speed corners and long straightaways without too many tight corners. I have wide gearing so this should suit the track well but it means I need a wide powerband as well. Help and advise or a point in the right direction would be great. Hi, Having campaigned in SCCA years ago, my best sage advice these days would be to contact a custom cam grinder. You'll get way better advice than from any big box vendor. Good luck and Happy Motoring! Quote Link to comment Share on other sites More sharing options...
vega Posted June 12, 2012 Author Share Posted June 12, 2012 Hi, Having campaigned in SCCA years ago, my best sage advice these days would be to contact a custom cam grinder. You'll get way better advice than from any big box vendor. Good luck and Happy Motoring! Anyone in particular that you have in mind? Quote Link to comment Share on other sites More sharing options...
luigi Posted June 12, 2012 Share Posted June 12, 2012 Jones cams, Owner is Mike Jones. Very good person. If you want to do a bit of trending, invest in engine analyzer. If this was mine, I'd make sure a got some EDM'd lifters. Did I miss it, what make heads are on this? Quote Link to comment Share on other sites More sharing options...
Scarab73 Posted June 12, 2012 Share Posted June 12, 2012 Anyone in particular that you have in mind? I have two recommendations: http://bulletcams.com/...and http://www.flowtechinduction.com/ Happy Motoring Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted July 22, 2012 Share Posted July 22, 2012 (edited) vega ?? well what did you decide? you were given a lot of related info,? Edited July 22, 2012 by grumpyvette Quote Link to comment Share on other sites More sharing options...
rsicard Posted July 25, 2012 Share Posted July 25, 2012 Warning: Don't go to 0.060 over without sonic testing the cylinder bores for adequate thickness. If the lower portion of the cylinder walls is thinner than desired, consider HARD BLOCK at least half way up the cylinder jacket. The 327 will have a narrow power band from 4000 to 6000 RPM. You will need to shift like a mad bandit wearing out your right arm. Start out with a late model SBC Vortec Block and stroke to 383. Then you would have some GRUNT and plenty of torque for straight line and corner acceleration. Using a 327 is wasting money on an under performer racing car. Quote Link to comment Share on other sites More sharing options...
vega Posted July 26, 2012 Author Share Posted July 26, 2012 The block and crank are getting crack tested as we speak. I dropped the block off at the builder last thursday. when i know you will know. also... mr 383. I am not here for an argument but you are wrong and I really don't have enough time to tell you why. I just check my email now after 5 days. I don't got online much, I don't have time. Bigger is not always better, this is personal experience. Quote Link to comment Share on other sites More sharing options...
roger280zx Posted July 26, 2012 Share Posted July 26, 2012 327 is in no way too small for a 2500 lb car. Cam/head combo and gearing can acomplish things cu. in. alone cannot. I'm interested to see what cam you end up with. Also what heads are those? I like the fat numbers around .500, spec a cam that takes advantage of that and isn't too much for your 10.25:1 and you'll be happy. Quote Link to comment Share on other sites More sharing options...
rsicard Posted July 26, 2012 Share Posted July 26, 2012 Vega: Crack testing is one thing. Sonic testing is another. When your car finally gets to the track, you will find all the weaknesses. It will be a shame to spend all that good money and not get the performance you are seeking. Again you will be shifting like a mad bandit to keep the RPMs above 4000 and below 6000 in the corners and straightaways. These are the FACTS, not emotions. Quote Link to comment Share on other sites More sharing options...
luigi Posted July 26, 2012 Share Posted July 26, 2012 There are many things that set the powerband of an engine, & there is nothing that says a 327 has to have a narrow powerband. In the engine masters competition there was a 331 that hit the pump @2500 rpm with 381 lb/ft. Low number was 377 lb/ft all the way to 6500 rpm. That doesn't sound narrow to me. Get an engine analyzer program and play around. Beware that if you really are gonna try to get the last bit outta it, you're gonna may need real long tube headers or at least do some testing to see what your combo likes. Good luck. Lewis Quote Link to comment Share on other sites More sharing options...
rsicard Posted July 27, 2012 Share Posted July 27, 2012 Went to Comp Cams and downloaded engine analyzer program. Loaded the known parameters and the horsepower slope came out steeper than 45 degrees. It peaked at 6000 RPM. The Torque curve peaked at 4500 RPM. That substantiated the narrow power band of the 327 engine. Best to shift and keep the RPMs from 4000 to 4500 RPM to keep peak torque to the wheels. Quote Link to comment Share on other sites More sharing options...
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