Guest V8Z Posted September 1, 2006 Share Posted September 1, 2006 Hello all.... I have a 1972 240z with a 350 5 speed and though pretty fast....it could be better!! The motor is a 350 part # 10067353 with 2000 miles on it. The specs. say 290hp and 305 torque. I want to put a roller cam, lifters, and rockers set up on and a set of aluminum heads. This motor has dished pistons which gives it a low compression. The heads I was thinking of going with are the ZZ4 GM heads part# 12556463. They are 58cc camber. Is the smaller the cc camber mean my compression will go up? Also, what is the diffrence in 1.6 and 1.5 roller lifters? I want the power to increase but I don't want a bad idel. I want it to stay as factory sounding as possible. So do you have any good cam suggestion with the ZZ4 heads? Or should I go with a diffrent head all together? I can buy a ZZ4 cam new fairly cheap of ebay, would that be a good cam for this set up? My target horsepower is around 400. Can it be done in the direction I'm going? I don't have the money to buy the same part over and over till I get it right so Any help would be great!! Thanks guys. Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted September 1, 2006 Share Posted September 1, 2006 400Hp isn't going to have a stock idle. Those are good heads, think about going with a small hydraulic roller like the zz4 cam. The heads will bump up the compression abit too. You might reach close to the 400HP mark but that depends on intake, exhaust, tune, etc. Grumpy probably has some cam recommendations, PM him directly, I'm sure he'll have a host of info for you. You must mean the 1.6 rockers in relation to 1.5's. Worth a few ponies and alittle bit of TQ, nothing to write home about though. Roller rockers do aid in longetivity of valve guides though. Something to think about for a daily driver. Quote Link to comment Share on other sites More sharing options...
Guest V8Z Posted September 1, 2006 Share Posted September 1, 2006 I guess more info would be helpful..... EPS Performance intake, Holley avenger 670 cfm carb. Shorty headers and 2 1/2 in. dual exhaust. The 1.5 and 1.6 I was asking about was for the roller lifters. I was thinking about calling a cam tech line like pro comp cams and telling him my engine specs and seeing what he may suggest. Quote Link to comment Share on other sites More sharing options...
280zwitha383 Posted September 1, 2006 Share Posted September 1, 2006 Engine Name: 350 LM1 Horsepower: 249 HP @ 5,000 RPM Torque: 304 Ft/Lbs @ 3,500 RPM Compression Ratio: 8.50 to 1 Block: 4 – Bolt, 2 Piece Rear Seal, 4.000” Bore Crankshaft: Cast Nodular 3.480” Stroke Heads: Cast Iron, 76cc Valves: 1.940” / 1.500” Camshaft lift: 0.390” / 0.410” Hydraulic Duration @ 0.050”: 195° / 202° 249hp leaves much to be desired out of a 350. 304 ft/lbs is pretty weak too. You definitely want to get smaller combustion chambers to raise the compression probably 1 point (9.5:1) on an iron head. It's generally accepted that you can run 1 more point of compression with an aluminum head. You have a lot to gain starting off with a 76cc head. You will have to do the homework as far as how much which combustion chamber will do what unless someone else is kind enough to look it up for you. - As far as the rocker arms, the 1.5 and 1.6 is referring to the ratio that the rocker arm increases the lift of the cam. Say the cam has .200 lift, a 1.5:1 rocker arm will make the lift .300 at the valve. The 1.6:1 will give you .320 - My friend has the same engine and I have always tried to get him to turbocharge it or supercharge it because the compression is there and turbocharging it on your own would be somewhat comparable (pricewise) to new aluminum heads and cam. Just a thought. - Regardless, almost any modification will give you a lopey idle which is nothing to be ashamed of. Quote Link to comment Share on other sites More sharing options...
Guest V8Z Posted September 1, 2006 Share Posted September 1, 2006 I think I still want to go with the heads and cam route, but just for some good reading who has a good turbo set up for a SBC? Also anyone suggest a good set of heads to use on a stock 350? What could get me the most from my engine. Thanks Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted September 1, 2006 Share Posted September 1, 2006 The best flowing stock GM low compression heads are the 882 castings, worked they make pretty good power. For high compression heads the vortec's for iron and the 18 degree heads for aluminum. Dart iron eagle platinum heads are good cast heads, AFR aluminum's are king of the hill. If your going turbo, you won't need any heads as 700Hp is attainable from a stock engine with appropriate boost, intercooling and tune, on pump gas. Turbo setup, don't know, HP performance out of Roswell, NM makes some kick butt systems capable of 8 second passes, single turbo, intercooled, nice! Quote Link to comment Share on other sites More sharing options...
Guest V8Z Posted September 2, 2006 Share Posted September 2, 2006 I have been looking at many types of aluminum heads on the net and with my dished pistons is it better for me to have a smaller combustion camber? The average is a 64cc chamber, the zz4 heads have a 58cc chamber. Dart offers a custom set that are 49cc chambers. I am thinking that I am 8.5:1 compression now so as I go smaller with the cc my compression will go up. Is that seem right to you? Is that also a good thing? Thanks Quote Link to comment Share on other sites More sharing options...
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