I'm looking for some ideas on rebuiding a '75 chevy 350 for my '83 pickup. The truck has a camper on it and has a 4-speed trans with 4.56 gears, 16" wheeels. I need to know what cam, intake, headers, etc would work good with this (and maybe some that wouldn't!). Thanks.
As far as intake, I think the Edelbrock Performer is definitely the best for your application. Really helps off-idle power and throttle response, and will help on the top end a little as long as you don't want to rev past 5500 RPM, which you shouldn't with your setup.
DynoMax CeramCoat headers are great for you application. They are ceramic coated with 1-5/8" primary tubes. 1-5/8" are great for low-end torque, which I am assuming you will be wanting lot's of. Again, they are not the best above 5500, but for your truck they should be perfect. They are about $215 (already coated) or so through Summit or other performance outlets.
Cam selection is a little bit trickier. That really depends on exacly how you plan to drive truck. I have a personal preference for Comp Cams. I have a 268H in my '74 Corvette, and plan to install a Comp Cam in my '76 Suburban one of these days. You can call them and tell them what intake, headers, compression ratio, gears, tranny etc you have and they will tell you which cam they recommend.
I would stay away from the Edelbrock cams. The Performer cam is hardly an improvement over stock, and the Performer RPM cam makes very little power below about 3500 RPMs, although it makes good top-end power.
Remember, the low-end torque is what will get your truck around town easily. Trucks are generally not expected to rev past 4500 or 5000 RPMs, although with your 4-speed you can do just about whatever you want.
What heads do you have, and do you know what compression ratio you have, or want to have?
You can check my website to see info on my '74 Corvette 350 buildup, although it's a bit more than you will want for your truck (lopey idle, likes to rev).
I agree with all Jeff's advice,but you might want to go with the 260H Cam,it will idle better and work better at lower RPM's.If your willing to sacrific it a little,the 268H will come alive and outpower the 260 on the midrange and top end.The performer is a great intake for a truck.Your heads will more than likey work fine the the cam/intake setup.As you already know this thing will drink gas with 4.56 gears and no overdrive.
Doug Thorley's are nice, Ive had them on my big block for 6 years now and no problems. Lots of low and mid range torque and they beat manifolds for the high range. 14g, industrial chrome plating, thick flanges. They are like $400 though they are money well spent.
I agree with the guys here about the Thorley headers but I couldnt seem to justify there price. I just bolted a set of Hooker Competition headers on my 350 and was very suprosed by the results. I had always heard headers were made for top end but they will put a big kick in the bottom and mid rpm's. I believe the 125 I spent was the best dollars I have spent on my truck yet.
I've never had this engine apart and don't know whats wrong with it. Its got a Q-jet, and dual exhaust, thats about it. The symptoms are it just doesn't have any power. You'd think that with a V-8, 4-speed, and 4.56 gears (even with the weight) it would be able to maintain speed going up some of the Misouri hills at 55mph, but sadly this is a challenge. I only use it a few times a year and get by, but wow, it would be lots more fun to drive if it had a better performing engine. The cam could be worn out....I need to examine for this. I'd like to pull it and work on it this winter. I assume compression ratio is low since its a '75, and I'm not familiar with chevy heads that much to tell which ones they are. A 5,500 redline sounds about right since it already turns around 3,000rpm at 60mph (I love the sound of a small block winding up though!). The body on the truck is near perfect (no rust Arizona sheet metal that hasn't been used in the crummy weather here in Iowa) so I'd like to keep it for a long time.
Sorry about the grammatical error. I typed that at about 3:00 a.m. after a long night of studying. It was supposed to be suprised. Also how much did you pay for your Thorley headers cause I wanted some but all the prices I saw were ridiculosly (I dont even know if I spelled that right) high.
ahhh surprised.. I dont know why that word didnt click in my head.. but anyway I dont have thorley headers (yet) but a good friend of mine just got them a few months ago for his truck and i beleive they were in the high 3's, definately under $400.. i also remember him looking around quite a bit to find em that cheap.. but, like was already stated, they are very high quality with THICK flanges... one thing you dont want to deal with is a warped flange.. I had endless headaches with an old set of headers and thin flanges.
good luck, if I talk to my friend with the thorleys any time soon i'll ask him where he got them and how much he payed exactly..