I want to change cylinder heads and cam in my 1986 305 from a Chevy van (casting number 10046164). My knowledge is limited regarding Chevy smallblock but I have an idea that includes http://www.summitracing.com/parts/EDL-5089/ and http://www.summitracing.com/parts/CCA-SK12-238-2/ . I plan to use four dual throttle and Megasquirt EFI Controller.

What do you think? Is this a mistake? Will the
compression ratio be wrong? And what about the valve clearance?

(hope You understand my Google-english)

 

First, welcome to TGO! Second, I believe you mis-typed the casting number of your heads. I think the last 3 digits will be 416. Please check. Way wrong heads. If you must buy heads, buy these: http://www.summitracing.com/parts/TFS-30300001/

 

Thanks!

Engine casting number : 10046164
Heads casting number : 14014416

Because of valve clearance?

The engine, which I have on the floor in my garage, the seller say is a replacement engine to a Chevy van. I read on Internet that 305 1986 have compression ratio of 9.3:1.
- have all 305 from this year 9,3:1?
- which compression ratio can be appropriate with the cam above?

 

Get a 350.

 

 

Easy in America, maybe not so easy in Sweden. Worth the cost of shipping? Probably better to do a 334 stroker, or take the plunge for something even better than a 350.

 

Look, first of all, you can't fit 2.02" intake valves in a 305, even bored 0.060" over. Second, those 185 cc intake ports will kill the 305 until 4000 RPM. Third, you really want at least 10:1 compression, but those 64cc chambers will put you under 9:1. You can have the TFS 56 cc heads decked 0.030" to get to 10:1 with FelPro 1094s. If you must have Edelbrock heads, it must be their E-Tec 170 heads, and because of the low compression, you'll need a milder cam and boost from a turbo.

 

185cc runners seem like a bit overkill and a recipe for failure behind a 305... unless you want to turn 7,000 RPM lol.

 

Thanks, seems to be a good advise!

I don't need to have Edelbrock, most important are that the engine works well.

 

What do you think about this combination?
http://www.summitracing.com/parts/TFS-30300002/
http://www.summitracing.com/parts/FEL-1094/
http://www.summitracing.com/parts/CCA-SK12-242-2/
http://www.summitracing.com/parts/PRO-66907/

Mistake?

 

Mistake? Depends. A cam like that, in a 305, will never see 20 MPG, will never pass an emissions test, will never fail to alert everyone around that you have a nasty camshaft swapped in, and will want a lot of gear. The given RPM ranges for all SBC cams are assuming a 350. Since you have a 305, you'd want to go with the next milder cam to get that RPM range. If the car is an automatic, you'll also need a looser torque converter.

 

Are You sure?

 

There are some things the magazines don't tell you. Like the fact that in-car vacuum is never as good as on-dyno, whether Q-Jet or Holley or EFI. And them calling it a good idle isn't the same as saying it's a stealthy idle, which it isn't. Car guys like them think Nascar V8s have a good idle sound, too. 13" is NOT good idle vacuum. 19" is good. 15" is the practical minimum for stock EFI, unless you want to invest huge money in custom tuning. We've discussed that 'Hate Me" 305 build before, in depth, in more than one thread. It's not a daily-driver build, period.

 

Driveability is a topic that's largely subjective.. for example I feel my solid roller 248/252 @ .050 cam with 9" of vacuum is perfectly driveable and I love driving it, other people would HATE it because of the shitty idle quality and poor brakes and it doesn't wanna start right away when it's cold.

To each his own I suppose.

Bottom line choose whatever you want. If you want more performance at the expense of driveability then that 224/230 will work for you provided you can find a GOOD tuner or if you're willing to carb it. If you want an easier time of things comp has a 218/224 as well but with decent heads you'll be leaving top end power on the table.

 

Thanks "Atilla the Fun" and "urbanhunter44" for interesting posts.

I have a manual gearbox, emissions is no problem and I have no stock EFI.
And I like some rough idle!

Is it possible to use 1.6 rocker arms together with CS XE262H-10 and TFS-30300002? Or can it be a problem with pushrod clearance for example? Otherwise maybe 1.6 rocker arms and CS XE262H-10 could be a good compromise?

 

Sounds like it has better drivability than most new cars, can't even tell they're running lol.

If you can take off without spinning the tires, it runs without having to do anything special while driving, and you enjoy it, it has good drivability.

 

Yeah that won't be an issue. The TFS heads show their maximum valve lift at 0.540, that cam lifts .462/.469. With flat top pistons, a stock deck and no grinding on the heads you should have plenty of room to spare.

Although I always, ALWAYS say check your piston-to-valve clearance. You can use some clay on the piston, bolt down your head and rotate the valve train. Pull off the head and check the clay for indentations.

 

Hello again!
I've heard bad things about Proform aluminum roller rocker arms. Can anyone recommend good 1,6 aluminum arms that do not cost a fortune?
What do you think about these? http://www.summitracing.com/parts/CCA-17002-16/

 

Why do you want 1.6 ratio rockers?

 

They give a little more hp than 1.5 ratio, but with sustained idle. Or?

 

It is not enough of a gain to make it worth while. It's patch work fix for a cam you should have had in the first place and really doesn't work that well. The bore size of a 305 shouts the intake valve which is more of a issue and saying that isn't a knock against building a 305. I am thinking that is why 305's respond so well to turbo's because it helps overcome that.

 

They screw with the valvetrain geometry. If you're starting with a new cam it's better to just pick the right cam to begin with. If you really want higher lifts and the same duration you'd be well served to swap over to roller cam conversion. And THAT will fit any 350 you get later on.

 

I did not know. When magazines builds Chevy smallblock and run them in dyno they often change to 1.6 ratio rocker arm. As I understand, with good results. Therefore, I thought it was a good idea.

 

I agree with internal. Go with the cam that suits you and just run the 1.5 rockers. With the 1.6's they push farther and then you start to have to worry about valve to piston clearance and the other valve train components. Just MHO.

 

Its not a bad idea... but it just compromises the valvetrain geometry. You'll find that depending on your heads you end up with you may not have the valvesprings or clearance to run that much more lift anyway. The 1.6 rockers also move the pushrods, and can sometimes cause issues of interference. The 1.6 ratio rockers also put more stress on the tappets and cam and with todays oils I dont know that it's a good long term idea. For roller cams this wont matter so much, but you will need stronger valve springs. Generally 1.6 ratio rockers are for people who have a nice engine built already, but need a little more power, but dont feel like going through the trouble of changing the cam. They're a band-aid for not enough camshaft.

Since you're building it now, you just buy the camshaft with the specs you want and use 1.5 rockers.

 

You're not trying to scare the OP are you? My 66GMC has a 305 (good deal on a short block from a big rebuilder that went out of business), 2bbl, 416 heads, a summit 1102 cam (similar to the OPs) and eyebrow flat tops. It idles pretty good. It lopes a little, but I idled it down a little to exaggerate that. What's killing me right now is the powerglide, but it's completely acceptable on the street. Even with the PG, tall tires and gears, it takes off from a light fine. It's not race, but it's fun. It'll be allot more fun with a 700r4 though.

 

Now that is pretty.Nice job!!.