Jimiboy wrote:It is an matching nr car with 340 engine, torqflite 727 and 8 3/4 rear end with 3.23 gear...
Its running fine
but, as always there are things that needs to be fixed, or that i want to change...
I have some problems with finding specs for the engine restoration. The only thing i know is that the engine is built up with forged pistons and another cam than original. plus headders... and a Holley 650 on the original intake manifold... i also think that i have cylinder heads from an 360(?)
I am curios about wich type of cam i should pic if i want to get some more power
and i am also curios about wich type of converter i should choose and if it is necessary to switch the gear in the rear axle???
Camshaft: I would call it
The main choise when you build an engine....Most of us want to build dual duty cars, i.e. street/strip-cars. The most important consideration is how much of the low rpm torque you are willing to sacrifice?
If you ask me, one of the main advantages with a V8 engine is that you get a lot of low rpm torque compared to most non turbocharged four-bangers for instance. Jump on the throttle and you get a lot of neck-snapping acceleration even at low rpm:s.
I don´t want to loose all of these pro:s myself if I would choose an aggresive cam profile. Yes, I can sacrifice a little but not all of it. How do you want your car to act on the street? How do you intend to use your car? I hope you get the picture.
Thanks to Mother Mopars wide diameter lifters (on ALL mopar engines, right?, I am not 100% sure) you can use camshafts with an agressive cam lobe, that is a very sticky cam. Hughes Engines (they have a very informative web site) sell such cams for instance. Some of the guys seems to like them and others don´t. My recommendations are that if you choose between a milder and a wilder cam, I would recommend you to choolse the milder cam. Why? I guess it happens quite frequently that people end up with too much camshaft. I think it happens more frequently than the other way around. Another recommendation is that you choose a cam with "a little more lift/a little less duration" compared to a cam with "a little less lift/a little more duration" (two similar camshafts). You with get more streetable power (more hp at lower rpm) that way.
How would I do? I think I would start from scratch with a bare block and build a stroker small-block for instance. If you sell your engine (if its not a number match of course), you will probably get a good start capital. Just a suggestion...
One last thing: It is a good idea to examinate your existing cam. To measure how muh it lifts is quite easy if you measure on the rockers. It may give you a hint about what profile your cam has. To get information about the duration is a bit trickier though.
Converter: Most of the guys here seems to be using converters with a stall speed of about 3000 rpm, so I suggest that you opt for something similar. The main consideration is to NOT choose a converter with a stall-speed higher than of your intake/camshaft-combo....
Gear ratio: To choose a 3.91:1 ratio will give better acceleration if you can get all the torque down to the pavement. On the other hand it will give your car annoying high rpm:s on the highway (unless you use an overdrive or a five-speed of course) and you will get low milage. 3.55:1 is the best compromise if you ask me. They seem to be quite hard to acquire though (quite rare and expensive...).
Good luck!
Btw: Try to use the search feature of this Message Board. I am sure you will get a lot of information that way.
Cheers
Chris
by Jimiboy » 04 Jan 2006 16:53 
(Thanks Roland for the tip =)
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