302 Z28/SBC combos

[Skip FIx]

A buddy is building a 69 Z28 and wants to keep it a 302. Steel crank decent rods, camel hump heads, factory intake.Probaby get some headers.Any body have cam suggestions other than factory they have used? Wants to sound like factory solid but pull to 7000. Small street solid roller would even be OK.

 

[MRHP]

I was going to run a -182 cam in a 302 I was going to build.

 

[Don Jacks]

Skip,I think that a Lunati flat tappet#30120740 would be a good choice for a 302 with a 4 speed,and4.11 gears.

 

[1958 delivery]

I kind of think that if you're building a clone/or restoring a real Z28 and sticking with a 302 that it would be best to stay with a factory blueprint cam otherwise build a bigger engine for better results

 

[models916]

I ran the GM HiPo service cam and the brown springs in my 68 302. Going to need a 4:56 gear to drive it around though. Just getting started at 7,000.

 

[chevymusclecars]

The original cam ran great if were over 3500 RPM, below that it is somewhat sluggish. I'm sure there are better cams that would give you a similar idle.

Bill

 

[303Radar]

You can always reach out to a cam builder and get a custom grind. I think all the cam companies have an online questionnaire which can be filled out to get a cam which will precisely meet specific needs.

 

[DonSSDD]

You probably need or have one of these for the 302?

http://www.hemmings.com/parts/item/5712.html?refer=news

I thought 409 or vette stuff was expensive.

Don

 

[chevymusclecars]

Typical Hemmings advertiser, that intake was an option. The car came standard with a high rise and Holley.

Bill

 

[303Radar]

Over $30,000 for only the intake and carb? Holy
I thought 348/409 items were pricey!

 

[1961BelAir427]

The Offy crossram is nearly identical to the GM one used on the 302's. I could be wrong, but I think Offenhauser built them for GM only with the GM casting #, snowflake, etc. in place of Offy's logo and part number. Again I could be wrong and don't want to spread misinformation, but after looking at detailed pictures of GM crossrams and comparing them to the Offy that I had (now belongs to TomK) I think they are the same casting.
From what I remember the crossram was an option and would come in the trunk ..... and that they did the same thing with factory optioned headers. Again, could be wrong as I'm no Z28 expert for sure.

 

[Skip FIx]

We'll contact the cam guys, but just didn't know if any of you all had a good one you've used.

 

[RED65]

So at $33,800, I still need to pay him for shipping?

 

[1958 delivery]

So at $33,800, I still need to pay him for shipping?

FOR THAT MONEY I WOULD HAVE A PRETTY NAKED GIRL DELIVER TO YOUR DOOR WITH EXTRAS INCLUDED.

 

[1958 delivery]

The Offy crossram is nearly identical to the GM one used on the 302's. I could be wrong, but I think Offenhauser built them for GM only with the GM casting #, snowflake, etc. in place of Offy's logo and part number. Again I could be wrong and don't want to spread misinformation, but after looking at detailed pictures of GM crossrams and comparing them to the Offy that I had (now belongs to TomK) I think they are the same casting.
From what I remember the crossram was an option and would come in the trunk ..... and that they did the same thing with factory optioned headers. Again, could be wrong as I'm no Z28 expert for sure.

The "snowflake" was a Winters Foundry trademark.

 

[HemiChallenger71]

The "camel hump" heads are a restriction. A solid roller would be great. Run rocker girdles if he wants to spin 7000+ often. I would think something in the 235-245 range intake duration @ .050 and 250ish on the exhaust. Keep it under .600 lift, with slightly less lift on the exhaust. Use 1.5 rockers. Basically the smallest solid roller you can find. I would prefer a 112-114 lobe separation, they might only grind it on a 108-110. Something early intake opening, say 105 to help with the low end power a bit but still run hard up top. Maybe even get a fully adjustable cam gear to play with the intake opening. On an engine that small it will make a difference.

Thats my .02 and along the lines of what I would do. I would also make it a 14-1 motor on E-85, but thats me.

 

[Skip FIx]

I saw and ad for a company that mills the ends of DART heads to look like camel humps and others.

http://www.castheads.com/disguise_work.php

 

[HemiChallenger71]

Stick shift car:

Yikes skip! 1K to make a cylinder head look factory? I'll pass.

 

[models916]

What kind of gear in the Z? I ran a 4:56 with F60 tires on my 68 back in the day. Best thing to do to that 302 is 3.75 crank. Nobody will ever see it. Might add a hundred HP. Otherwise you still have a small engine that has to rev. to get the power up.

 

[1961BelAir427]

I agree with Mike. No one would ever know if you were to build it with more stroke. Even if it were just a small change to 3.25" (327) it would help out in the torque and driveability department. You could make it look period correct or even 100% restored on the outside...down to numbers matching block/heads and still have more cubic inches and power. The ONLY reason Chevy built them with a 4" bore & 3" stroke was the rules for the race series.