logan1 Posted February 4, 2013 Share Posted February 4, 2013 (edited) Ok so I'm upgrading my SBC 350 a lil bit and had a few questions: First my car is a 1970 240Z with suspension is GC coilovers with tokico blue shocks and upgraded 1" sway bars in the front and as soon as i get the brackets welded a 7/8" in the back. I am running a built T5 out of a 1993 5.0 mustang connected to a R200 4:11 open diff. Wheels and tires are Rota RB's; 17x9 (-13 offset) front with 255/45/17 and 17x9.5 (-19 offset) rear with 275/40/17 tires. The car is 80% street and 20% autocross/strip. The car weighs in at about 2500lbs all included. I would like to have as aggressive a cam as possible while keeping it streetable. I am also looking to run power brakes but am willing to run a vacuum reserve is required. Chevy 5.7L SBC 355 4-Bolt main Block has been bored 40 over 882 heads (76cc chamber) Edelbrock RPM airgap intake Holley 600cfm carb New Comp 268H cam kit. flat top pistons Shorty Hugger Headers I am have currently bought the following parts to upgrade my motor: Patriot Freedom 23 degree Aluminum heads. (64cc chamber, 185cc runner, 2.02 intake and 1.60 exhaust, 0575 max lift) Edelbrock pereformer intake with JEGS liquid filled temp gauge MSD billet distributor MSD coil MSD plug wires Summit racing mutli spark ignition box with 5500rpm rev limiter. Aluminum water pump. I think i'll have around 9.75:1 compression with the new heads My Questions are: I would like to take full advantage of the new heads and i think a new cam will help me get a good bit more performance out of my motor. I have been looking at the cams listed below. Let me know your thoughts and if you know of any other cams that will gibe me better performance please suggest. Comp Cam 292H-10 292/292, Lift .501/.501, Chevy, COMP Cams Magnum Hydraulic Camshafts 12-213-3 - SummitRacing.com Comp Cam 286H286/286, Lift .490/.490, Chevy, COMP Cams Magnum Hydraulic Camshafts 12-326-4 - SummitRacing.com Comp Cam 305H 305/305, Lift .525/.525, http://http://www.summitracing.com/parts/cca-12-214-4/overview/make/chevrolet Edited February 4, 2013 by logan1 Quote Link to comment Share on other sites More sharing options...
Robftw Posted February 4, 2013 Share Posted February 4, 2013 You should probably 10.5 compression with those cams, if its mostly street / autox go for high low-mid hp/tq. Your car is limited to 5500 which makes all 3 of those cams useless, you're only getting half the potential out of them. The car will drive like crap on thw street until you reach the optimal rpm for each cam. Try for .460 to .480 lift and around .215 to .225 duration at .50 You'll enjoy it much more Quote Link to comment Share on other sites More sharing options...
Robftw Posted February 4, 2013 Share Posted February 4, 2013 Actually, now that I think of it.. I used to have an isky 280 mega cam. That was in my 355. I loved that thing, I had iron heads at the time 10:1 Here is the dyno, 700r4 transmission and a 2600 stall. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted February 4, 2013 Share Posted February 4, 2013 (edited) I have actually used the comp 292 cam in my camaro. I still have it actually. It has a nice lopey sound and makes good power. Power brakes will still work. I would use it on the street no problem. Bump your rev limiter to 6500 and shift at 6k if you like going fast. My comp ratio was 9.5:1. Edited February 4, 2013 by skirkland1980 Quote Link to comment Share on other sites More sharing options...
Pyro Posted February 6, 2013 Share Posted February 6, 2013 I ran the 292H with my 350 powered z (t5, 3.90 gear, 200cc dart iron eagle, long tube headers, rpm intake, 750 carb). Great cam but a rough idle. Once moving the cam was very streetable. Useable power from 3000 to 7000. Ran a between 117 to 120mph in the 1/4 mile around 11.7 et. Did a best of 10.7 at 135 with a 175hp shot n02. With block huggers, single 2.5" exhaust, old fuelie double hump heads, 292h cam, rpm intake, and 750, it ran 12.7 at 110 mph. So, it drop a full second in the 1/4 mile with better exhaust and heads. 12.3 with better exhaust then 11.7 with better heads, installed in that order. After your head swap, I think the block huggers and 600 cfm carb are your biggest hp killers. And the hp will be choked off even more with the bigger cam. The performer intake and 5500 rev limiter is not good for the bigger cams. I would stay with the rpm intake no matter what cam you use. I don't like air gaps, but like the regular rpm intake. Also get a holley 3310, 750 vacuum secondary. Last thing, a bigger cam will need 20 to 25 degree of ignition timing at idle and use zddp oil additive to keep the cam lobes happy. Quote Link to comment Share on other sites More sharing options...
logan1 Posted February 9, 2013 Author Share Posted February 9, 2013 thanx for all the good information guys. Looks like the 292H is the winner; I found thie video on youtube of a SBC 350 running the 292H cam and it sounds amazing. I just bought a Holley 4778-4 700CFM double pumper to go with my new setup. I also am planning to change the rev limiter to 7000rpm. Also now that i own a welder i am considering buying a cheap set of long tube headers of craigslist and modifying them to fit my 240z. Quote Link to comment Share on other sites More sharing options...
Pyro Posted February 9, 2013 Share Posted February 9, 2013 I used the Hooker Super Comps for sbc conversion for a z. I bought them 10 tens ago so not sure if you can still get them. The headers required a little modification to get into the car because the headers were not designed for the setback position (JTR position), plus the scatter shield for the clutch was in the way, and I also converted to 2-1/2" collector flangers for more ground clearance. I also seen some early 70's corvette headers that fit pretty close, but still require mods. I brought the Dart 200cc iron eagle heads and used the springs that came with the heads. The springs were a little stronger than the springs recommended by Compcam for the 292H. I believe Dart heads came with springs for a roller cam. Anyways, the 292H would float the valves at 7200 rpms and pull hard to 7000. However, my best et's were made with 6500 shift points even though I would swear the engine was still pulling very hard past 6500. I have a 5" Autometer tach so I'm pretty sure about the RPMs. Good luck with your cam! Quote Link to comment Share on other sites More sharing options...
Mikelly Posted February 10, 2013 Share Posted February 10, 2013 I have a set of those headers PYRO mentions above I'd gladly sell you. I bought them for JNJracecars and didn't use them. They're ceramic coated, but you could cut them as needed and reweld them. Let me know. Mike Quote Link to comment Share on other sites More sharing options...
logan1 Posted February 11, 2013 Author Share Posted February 11, 2013 I have a set of those headers PYRO mentions above I'd gladly sell you. I bought them for JNJracecars and didn't use them. They're ceramic coated, but you could cut them as needed and reweld them. Let me know. Mike PM me a price with shipping to Broken arrow, Oklahoma 74012. Quote Link to comment Share on other sites More sharing options...
Mikelly Posted February 11, 2013 Share Posted February 11, 2013 You got a PM... Just let me know... Can go out this week, and I take Paypal. Mike Quote Link to comment Share on other sites More sharing options...
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