Need more Vroom from my 350

[walker]

I don't know who might remember my SBC saga but in the end I put in a GM crate 350 into my '67 LWB C-10, out of desperation. It has a performer intake, edelbrock 600cfm, stock exhaust manifolds, mallory HEI. It was running poorly as of late and I looked into it tonight and found that my advance wasn't advancing. I got the advance working, and advancing to what I would guess is about thirty something BTDC, it started pinging so I retarded it a little. It left me wanting a little more horsepower though.
So here is my question, what are the steps I can take to get the power. I have considered going to a TBI set up for easier starts, more power, better economy. Don't get me wrong I am not trying to get 30 mpg, while burning rubber, or anything like that, but 14 mpg would be nice, and fuel economy is not a huge concern for me. But I would like to hear some more options. I would love to have a blower motor but don't think that fits in to my life right now. I have a pair of dart heads left from my last engine, only have a couple hundred miles on them(long story). They are a 196intake 160exhaust 76ccintake, to the best of my recollection. Would it make sence to install these heads? I am not sure what type of heads the GM crate 350's come with, although I can't imagine that they are anything but smoggers, so I don't know if this is a good option or not. Also, the TH400 has a stock converter in it. It has such a low stall speed that I have difficulty in breaking the tires loose, even though I have 4.11's in the rear. The exhaust system has been replaced with a dual pipe system with turbo mufflers, from one of the vendors.
If anyone has some good options for me I would love to hear them. Thanks, Andy.

[SweetandLong68]

Yeah, if you timing is off it will kill the power big time.

Also...What cam does this engine have in it? Cam and heads is where the power is at.

lata
CHRIS

[breeh]

Get a big block

[SweetandLong68]

Or just put the BIG SHOT on it

lata
CHRIS

[walker]

The cam is the stock GM unit as well. After I blew up my rodded engine I bought the bone stock GM crate job to put in her, as I needed an engine fast so I could commute to work. I don't need it to commute anymore though. I am also not looking to replace the engine, just modify it. I was happy with the previous engine that had 2.02 fuelies, big cam, high compression, etc, until I developed a crack in one of the heads. I pulled it apart, put on those dart heads, ran it only to find out I had a crack in the block too
I guess I would like some of that power back. I also miss some of the niceties of the FI on my 94 silverado that I sold to drive my '67.
So, it looks like a new cam, and slap the dart heads on? Any cam recommendations would be nice. I don't need a huge cam, as I am not trying to win down at the strip or any thing, just racing between streelights.
Also, any recommendations on my converter?

[724wdcopper]

is your crate engine a perimeter bolt valve cover or center bolt (88-up)? the old style crate motors only have i think 8.1 to 1 comp ratio. to bump it without changing pistons, small chamber heads are required. might look into that, first.

[walker]

It is the older style 350 with the perimeter bolt valve covers.

[Bowtie67]

The stock GM crate motors are not performers by any means, without going for broke and trying to get some power out of this motor some simple things can be done to boost performance and fuel economy.

first thing is Headers!!
You can hit a junkyard up and get a set of used Vortec heads or spend a few and by new, there not gonna raise compression but they will folw a lot better than those heads you currently have. You'll also have to change the intake.

To really perk the engine you need to put a descent set of heads on that will have a small combuston chamber like 64cc, the vortecs are 76cc, changing out to 64cc will get you about a 1.2 compression increase, witch equates to about 4hp per cylinder, add to the fact of a descent set of heads like darts torquers, Edlebrock RPM, TFS and some other quality heads will also increase performance anywhere from 20 - 50hp. The stock crate motors where usually 8.5cr which would bump compression up to about 9.6 then your next step is picking a good cam without overdoing it and killing yur gas milage. The stock cam in these motors are not going to perform. The comp XE268 with above mentioned heads with the raised CR and headers should yeild 375 - 400hp..Go with a roller cam and get even more out of it. I would also recomend the aspect of also replacing the performer intake to the airgap rpm or then go to a fuel injection setup, a MPFI will out do a TBI setup in performance and fuel economy.

Adding a Fuel Injection may give you a benefit over the carb on your current setup but I think it would be minimal.

[stea]

Walker, check this link http://www.chevyasylum.com/chp/goodwrench1-1.html, great article on what to do with the basic crate motor

[gr8scott51]

Can I recommend you have a local shop hook it up to their diagnostics machine? It was the best $300 I spent, getting my valves adjusted just right and my carb rejetted and timing reset. All things that I have done for years with timing light and feeler gages, and thought I had right to start with. Another simple (inexpensive) power gain would be a spacer plate between the carb and intake.

[walker]

That is great, the article on the crate 350 sounds about like what I need to do. Maybe I'll take those heads apart and see about porting them before I put them on. Add a cam, and it sounds like I'll be where I would like to be. Any recommendations for the stall speed of a converter for that th400?

[dinnut]

call a company that does torque converters or a cam company and talk to them about what cam you are going to use and which torque converter to use with it. the xe268 was the cam i was looking at but do not have the time right now to change the cam out in my truck... its actually what cam josh recomended i use. i think i might go with a 2000 or 2500 rpm stall converter.... is this too big? anybody now?

[Zonaman]

Looks like you have about the same set up as I do. I was getting about 12 mpg till I replaced my TH350 with the 700r4. now I'm getting about 14. Never touched the timing or carb. At present gas prices that worth about $300.00. Not much difference in power though.

[bubbastrick]

To really perk the engine you need to put a descent set of heads on that will have a small combuston chamber like 64cc, the vortecs are 76cc

Just one correction, the Vortec heads are ~64cc not 76cc.