straight six head conversion project

[Green77c10]

So I bought my '77 chevy stepside, c10 2wd and my biggest complaint about the vehicle is the integral cylinder head. It makes a lot of stuff on that engine harder to get too, take twice as long, and not to mention, NO AFTERMARKET PARTS. Now being a 19 year old male that loves to tinker, modify, and make things better in general, that will not do. So I started shopping the junk yards to try and find parts to change it to the standard, earlier style head. After about a month of looking I found a 76 with a cylinder head in good shape, and a header for it to boot! But no intake. I finally rounded up an intake manifold last week, and I'm getting itchy to start. I got my pay pal pending to get the new power steering brackets that will fit it, thanks to Redden05.

The heads off getting resurfaced, and the header is with one of my buddies who is going to do a little work on it (a couple minor dents, and sandblasting). I should have taken pics for a good before and after comparison.

I'm not the most mechanical person, and I'm young and inexperienced so it should make for a fun time. I'll keep this thread updated with pics and such of the project.

[ton*loc]

what else you getting done to the head ?


you planning on any power adders ?

[Green77c10]

I was thinking about it, but cant really justify the money in my financial situation of just graduated and moved away from the parents about a year ago. So nothing in the head. I'm not going super crazy with this engine, at least not soon. I do plan on a nice intake and a Holley 390 within about the next year and a half sometime though.

[Green77c10]

Its my daily driver, so I don't want too much.

[87Lowrider]

Good year - how bout some pics!!!

Ken

[ton*loc]

wors are you sure the 390 is enuff ?

[Green77c10]

i think it will be, its what clifford and a local six cylinder hot rod shop recommend for that engine, at least to start. Like I said, its for street use. If I was racing I'd save up to get the triple side draught webers

[D13]

390 is more than enough for a stock 250. A 500 is the limit and that is only because of the vacuum secondaries. 390 on a water heated Clifford is supposed to be the best combo for street driveability.

[Green77c10]

Ok, I got some pics to put up.

The truck:



The Engine:

[ca180]

I'm starting to wish I had given up my six.... It's amazing that when you're young you think that bigger engines are better... Only now do I realize that the six was cool...

[Mr79C10]

Green77c10, I have the same motor. But mine did not come with P/S Im adding one but I was wondering if you could post a pic of your alternator location. Your P/S pump is located where my Alt is.


Much Thanks

[Green77c10]

yea, ill try to get a pic up of the alt in the next couple days

[Green77c10]

UPDATE: Got the cylinder head back from the machine shop today, and they cleaned the old oil all off of it, but id like to clean it up more, such as inside the actual exhaust and intake ports, and im hoping someone has some tips on that or just the standard brakleen and stiff brush?

Also, it has some kind of build up on some of the valves, thats pretty hard packed on there. once again, some tips on how to clean it up?

[manimal]

you sent it to a machine shop and they didnt CLEAN it!? The build up is probably on the exhaust valves and can be removed with a wire wheel,but you have to disassemble the head....You may want to take the head back to them for a valve job. Around here it is like 75-90 bones. Good luck. And BTW nice looking truck.
-Lance

[Green77c10]

Sorry guys, I started this thread a long time ago and then put the project on hold for far too long, due to mainly my financial irresponsibility and LOTS of things coming up. Its time for an update! I decided to do more than just convert the head, but build it up as well! Build outline is as follows:

Cylinder head: Took it back to the machine shop to get new and bigger valves put in! 1.84 intake, no modification to the exhaust. This was reccomended to me by my machinist, because he said this will give it a lot of low to mid range torque, as opposed to the 1.94's which are so popular but are mainly for higher rpms and a lot hotter builds, according to him anyway. It took him a lot longer than he had planned to do the job, so he gave me a free upgrade to the SBC style umbrella seal Stainless exhaust valves, upgraded springs and some extra machining in case I ever want to throw a huge cam in it. Pics of the head coming soon!

Intake: Stock intake for now, though I am shopping for a used Offy for a good price!

Exhaust: I have a header for it, apart from the manifold the stock exhaust doesnt seem too restrictive, except for the muffler and tailpipe. That will change to a Flowmaster 40 and a wider tailpipe.

Cam: Still trying to decide between two low end towing/rv cams, still need to buy that part. last expensive piece I need to get started!

Carb: This is the part that will be experimental, as I have only talked to maybe one person who has done this with a straight six. I pulled a large bolt pattern Rochester 2 barrel off of a 78 Monte Carlo's 3.8 v6, that will be rebuilt, adapted, and have linkage fabricated for. If I've done my research correct, it should flow at about 325 CFM.

This build was planned with the help of the machinist I went to, who helped his father build several of these sixes, who raced them and has a few trophy's in the shop. he had one that ran 9's. He assured me that the combo of these valves, the right cam, and a good 2 barrel would make this a pretty hot street engine with a ton of low to mid range power, but certainly not lacking in the high rpm range. Should be fun.

[Green77c10]

Just a quick note, Im not planning on using the factory intake permanently, just to get it driving or until I can find an offy to put on. I know the 1bbl manifold will inhibit the 2bbl carb a little.