350 build

[1980c10]

I should be going to pick up a parts truck tonight. It is a 84 2wd lwb  for $550. I looked at it yesterday, it has a '75 350-looks stock with a 4bbl q-jet, started right up and runs good. It is tucked away behind some cars and the bed was full of stuff so I gave him some time to clean it out and make sure it will go down the road. I will post some pics. btw the truck has power windows tilt wheel etc so maybe i will get some extra parts.

[1980c10]

Update. Got the parts truck home. The 350 runs good, plenty of leaks on the truck, smoked most of the way home from coolant and transmission fluid leaking. maybe I won't have to rebuild the q-jet. Also stoppped in a transmission shop today to ask about some bushings in the shifter for my sm465 and walked out with a rebuilt nv3500 5 speed for $400 . It was work they did for somebody that never picked it up. so add a little work to the project. Also I need to find a better machine shop to do the work as I heard some pretty bad things about the shop I was going to go with for the engine work.

[eventhorizon66]

maybe I won't have to rebuild the q-jet.

I wouldn't count on it.  Not if you want it to run its' best.  You should give that Cliff Ruggles book I posted earlier a read through.

[1980c10]

pulled it in the garage after burning off a tire about a 1/4 mile long-mine won't do that. looked at the q-jet and its dirty bit it does run great. I will rebuild it just to make sure.

[1980c10]

Update: This engine is most likely going to get vortech heads, also the engine should be out of the truck this weekend if all goes well and in the machine shop on monday, I need my garage back my other vehicles are ice covered plus they need some misc. work too and it is too cold outside.

[1980c10]

Update: Engine is out of the truck, disassembled and at the machine shop. I picked up a set of heads today casting #062 vortech 350, they are used; bought from craigslist and when I went to get them turned out it was a friend of mine from H.S. so I am a little more confident that they will be good, couldn't see any cracks anyway. Also picked up a nice set of tall billet aluminum valve covers for another $25 from him. so far the plan is to bore block as needed, flat top pistons. Balance rotating assembly, a little heavier springs for the valves, any recomendation on rocker arms for these heads? heard I need roller tip.
also looking for some opinions on this cam: http://www.summitracing.com/parts/CRO-00904/

[eventhorizon66]

Are you going to have the heads inspected, magnafluxed, etc.?

You do not need roller tip rockers.  They are just a performance enhancement as they reduce friction and valve side loading.  You do need to use self-guiding rockers if you retain the factory press in studs.  If you have your machine shop drill and tap for screw in studs, also have them machine for guide plate and then you should run regular rocker arms.

That's fairly typical mild street cam.  A Summit 1103 cam would be exactly the same for a lot less.  David Vizard recommends cams spec'd on a 108 LCA for a typical street performance 350.  He says that you are basically forfeiting torque everywhere in the powerband if you don't.  I've got no personal experience to back this up but he does apparently.

When I build my 350 up I'll go with some sort of Vortec head variant, about 10:1 CR, and a cam with about the following specs:

262/262 ADV DUR
218/218 DUR @ 0.050"
.493"/.462" Lift (with 1.6:1 intake and 1.5:1 exhaust rockers)
108° LCA
4° Advance

Based on his writings, I expect this combination to be very docile with good low-end, but still offer 420-430 ft-lb potential (with excellent tune and well thought out components of course).

http://www.amazon.com/David-Vizards-Build-Horsepower-Design/dp/1934709174/ref=sr_1_1?ie=UTF8&qid=1291608071&sr=8-1

http://www.amazon.com/Build-Chevy-Small-Blocks-Budget-Performance/dp/1932494847/ref=sr_1_2?ie=UTF8&qid=1291608071&sr=8-2

[eventhorizon66]

BTW here are some very nice cheap springs.  According to Chevy High Performance magazine, they are drop in for Vortec heads.  These are the same springs used in the ZZ4, ZZ383, and CT350/400 crate engines from GMPP.

Springs:
http://paceperformance.com/i-5136483-12495494-small-block-chevy-lt4-valve-spring-kit-used-on-1996-lt4-engines-zz4-fast-burn-385-crate-engines-16-springs-1-32-diameter.html

Retainers:
http://paceperformance.com/i-5135247-19171528-valve-spring-cap-kit-lt4.html

[1980c10]

Those are the exact springs, The cam would be through the machine shop if I give them the okay on it, I don't know their price yet but I'll mention the summit cam to them if it's much more since they are pretty much identical.
The heads will be tested. They will also get a 3 angle/radius valve job and the screw in studs and some polishing and maybe a small amount of porting on the exhaust side. btw The heads will be machined, assembled and installed on the block by the machine shop, that way I can't screw it up.
   
thanks

[1980c10]

update; cliffs high performance will not be able to complete the carb work until july or august. So I am going with this guy;http://bigsperformance.com/ he is a local guy that comes recommended by people I trust. At this point I am going to have him rebuild/modify the q-jet. however I have yet to bring him my cam specs and the carb, but i think it will work. If something isn't going to work with my current carb; I will probably go with a new holly modified/adjusted by him for my application. One nice thing about having this guy take care of it is that he will run the carb in his shop to test it and ball park the setting and then he will be able to fine tune it in my truck and being local I don't have to send it and If I have any issues I can drive to his shop to get it taken care of. He says he can do a little more with a holly but mpg will suffer, but he also says he can make this q-jet go.

[1980c10]

Another question: I currently have a cable driven speedometer and will be installing the nv3500. can i get a newer electronic oem speedometer-use it-and-if so-does the speed sensor send the signal to a computer or someting before it reaches the speedometer? If so the only other option I see is buying this http://www.gaugeguys.com/cablex.htm and i would rather not spend another 325 if there is a cheaper solution. Ides, thoughts, any one do this?

[1980c10]

^^^^Anyone???^^

[bobcooter]

Just a word of caution. When I was building my 350, the guy who did my machine work told me not to run the Vortec heads with flat top pistons. Too much compression and it eventually blow up. He builds a lot of racing engines so I took him at his word. I've heard other people say the same thing. I think if I already had the Vortec heads I may consider running a dished piston.

[1980c10]

 

Just a word of caution. When I was building my 350, the guy who did my machine work told me not to run the Vortec heads with flat top pistons. Too much compression and it eventually blow up. He builds a lot of racing engines so I took him at his word. I've heard other people say the same thing. I think if I already had the Vortec heads I may consider running a dished piston.

I am hoping for 9.5:1 ish.
I haven't actually calculated what it will be.
assuming;
the heads are 64cc
standard head gasket.. so .040
4.030 bore and 3.48 stroke
7cc valve relief??
the block wont be zero decked so .025??
These numbers calculate to 9.59:1
I am not too sure if I am correct with these numbers btw the block has never been machined. Does anyone think I am way off with these numbers?

[bobcooter]

I had a set of 882 heads and the flat top pistons. My machinest told me that would around 9.5 to 1 compression. The 882 heads are 76cc.