Intake and Carb Swap
06-07-2015, 02:00 AM
#61
I omit the transmission costs because those are not the motor and are things I already planned on doing when money and time come around.
I agree with the part about the rod bolts, and really wish I had been more involved in the engine building process, because you are right this means engine disassembly which at that point you might as well do pistons and rods..hell even stroke it. I haven't heard of this compression ratio thing but it makes sense. I already knew valvetrain upgrades were needed like I said, obviously heads too.
I tried finding good reading on "needed CR for a given rpm" or the like and couldn't really find much. I would like to know how this is computed and why an engine with over 9:1 compression would not spin to 6k.
I think $6k is a good upper-end ballpark figure but I believe it can be done for less with what I have and the availability of parts. Not arguing nor am I interested in starting anything, I know I am a novice and do not hide that fact, especially with engine building. With a stock bottom end what's safe then? 5500? 5750?
I agree with the part about the rod bolts, and really wish I had been more involved in the engine building process, because you are right this means engine disassembly which at that point you might as well do pistons and rods..hell even stroke it. I haven't heard of this compression ratio thing but it makes sense. I already knew valvetrain upgrades were needed like I said, obviously heads too.
I tried finding good reading on "needed CR for a given rpm" or the like and couldn't really find much. I would like to know how this is computed and why an engine with over 9:1 compression would not spin to 6k.
I think $6k is a good upper-end ballpark figure but I believe it can be done for less with what I have and the availability of parts. Not arguing nor am I interested in starting anything, I know I am a novice and do not hide that fact, especially with engine building. With a stock bottom end what's safe then? 5500? 5750?
06-08-2015, 01:48 PM
#62
5th Gear Member
Join Date: Aug 2004
Location: ABQ, NM, USA
Posts: 2,593
Safe for how long?
Why the need for 6k rpm? Are you going racing?
Do your future cam, heads and shortblock all converge on that rpm?
It all comes down to the goals of the car and purpose. As the quest for more power goes up, so do the costs and breakages of those and collateral parts.
Why the need for 6k rpm? Are you going racing?
Do your future cam, heads and shortblock all converge on that rpm?
It all comes down to the goals of the car and purpose. As the quest for more power goes up, so do the costs and breakages of those and collateral parts.
06-08-2015, 05:06 PM
#63
I don't know how to answer the question about safe for how long. I imagine with upgraded rods/pistons/hardware, roller valvetrain, and good heads I could run 6000rpm MAX all day long. I really try to do my reading before sounding stupid, but as you all know every motor is different and just because one guy did it doesn't mean it will always work. I see many setups run to 5500 and quite a few to 6k, hence my questions...
Back on track to the intake/carb swap. I finally found a decent set of carb studs, got all my vacuum fittings and hose necessary for swap, and I am currently modifying the stock throttle cable bracket to work with the new carburetor. The carb body prevents the stock bracket from sitting where it needs to. So I am chopping off one side of the stock bracket, and adding a reinforcing tab/bracket that will be fastened to one of the unused intake bosses in the back of the intake. I just ordered an intake bolt kit too, in black.
I am spending time to color match small things...progess is progress...
Back on track to the intake/carb swap. I finally found a decent set of carb studs, got all my vacuum fittings and hose necessary for swap, and I am currently modifying the stock throttle cable bracket to work with the new carburetor. The carb body prevents the stock bracket from sitting where it needs to. So I am chopping off one side of the stock bracket, and adding a reinforcing tab/bracket that will be fastened to one of the unused intake bosses in the back of the intake. I just ordered an intake bolt kit too, in black.
I am spending time to color match small things...progess is progress...
06-09-2015, 02:38 AM
#64
4th Gear Member
Join Date: Nov 2013
Location: arizona
Posts: 1,398
where did you read that, thats ridiculous.
06-09-2015, 02:24 PM
#65
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if you spin cast pistons to 6 k very often, they may break . . if you spin stock rod nuts or bolts to 6k very often, they may break.
just because some people do that or do that with an unbalanced engine doesn't mean it is ok and that it wont blow up.
also, you need screw in rocker studs or pins in the stockers, if you install a bigger cam or stiffer springs.
you need to disassemble the engine to do the rods and pistons so you might as well do it right and rebuild it.
you need more compression if you have a 6 k engine.
you need 350 gears if you have a 6 k engine.
you need a high stall converter if you have a 6 k engine.
you should build your trans if you have a 6 k engine.
ok, im tired of typing now.
if you spin cast pistons to 6 k very often, they may break . . if you spin stock rod nuts or bolts to 6k very often, they may break.
just because some people do that or do that with an unbalanced engine doesn't mean it is ok and that it wont blow up.
also, you need screw in rocker studs or pins in the stockers, if you install a bigger cam or stiffer springs.
you need to disassemble the engine to do the rods and pistons so you might as well do it right and rebuild it.
you need more compression if you have a 6 k engine.
you need 350 gears if you have a 6 k engine.
you need a high stall converter if you have a 6 k engine.
you should build your trans if you have a 6 k engine.
ok, im tired of typing now.
06-09-2015, 08:28 PM
#66
4th Gear Member
Join Date: Nov 2013
Location: arizona
Posts: 1,398
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yes, i didnt want to write an essay as to why you "need" more compression . . in your case, you currently have 9:1 static compression and a mild cam so you might have around 7.5 dynamic compression . . in general, the bigger the cam you use, the less compression you will have due to the later closing time of the intake valve so if you put a cam in there that will rev your engine to 6000 rpm, your dynamic compression will likely be reduced so it needs to be corrected for you increasing your static compression . . this is why many cam mfgs have notations in their cam descriptions to use at least 9.5 or 10.5 compression with a particular cam etc.
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yes, i didnt want to write an essay as to why you "need" more compression . . in your case, you currently have 9:1 static compression and a mild cam so you might have around 7.5 dynamic compression . . in general, the bigger the cam you use, the less compression you will have due to the later closing time of the intake valve so if you put a cam in there that will rev your engine to 6000 rpm, your dynamic compression will likely be reduced so it needs to be corrected for you increasing your static compression . . this is why many cam mfgs have notations in their cam descriptions to use at least 9.5 or 10.5 compression with a particular cam etc.
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06-13-2015, 01:53 AM
#67
I am a first timer with setting up a new carburetor and intake system, so I of course don't have some parts I need. Soon I will be purchasing an adjustable throttle cable bracket. I though I could modify original, but soon realized the time spent is not worth it and the ones you buy look cool and adjust easily.
I also wasn't sure if I would need linkage accessories to setup the new carburetor. Well I am pretty sure I do now. The carb manual says that I need to hook a spring up to the carb kickdown lever which is for the kickdown rod. The movement relationship/ratio between the main throttle lever and the kickdown lever is not the same, and the spring is to ensure the rod is forward until it needs to move rearward.
I remove a screw which holds this kickdown lever to the main throttle lever, and then attach a spring to the lever which pulls the lever (and kickdown rod when attached) in the full forward position. Then this small lever is caught by the main throttle lever moving towards WOT which engages the kickdown rod in its max rearward position (downshift position). Sound right/make sense?
This is what I'm talking about:
http://www.summitracing.com/parts/sum-m08070/overview/
Little things like this I would have no way of knowing in advance...especially when the carburetor says it works with ford kickdown.
I also wasn't sure if I would need linkage accessories to setup the new carburetor. Well I am pretty sure I do now. The carb manual says that I need to hook a spring up to the carb kickdown lever which is for the kickdown rod. The movement relationship/ratio between the main throttle lever and the kickdown lever is not the same, and the spring is to ensure the rod is forward until it needs to move rearward.
I remove a screw which holds this kickdown lever to the main throttle lever, and then attach a spring to the lever which pulls the lever (and kickdown rod when attached) in the full forward position. Then this small lever is caught by the main throttle lever moving towards WOT which engages the kickdown rod in its max rearward position (downshift position). Sound right/make sense?
This is what I'm talking about:
http://www.summitracing.com/parts/sum-m08070/overview/
Little things like this I would have no way of knowing in advance...especially when the carburetor says it works with ford kickdown.
06-17-2015, 01:22 PM
#68
So I ordered a billet throttle linkage kit from AED. It mounted and the springs worked fine, however the throttle cable bracket was incorrect for my application. I looked at a few different sites, and I noticed none of the "Ford" type of throttle cables look like mine.
Mine looks like the square gm one that pressed into the mount with clips. When I look at stock 69' photos my cable is stock. Do I need to order one for a gm cable? I just wanted an adjustable throttle bracket with dual return springs and for my cable to just pop into the square hole.
What cable type do 69's use? Because it is apparently not "Ford style" and I would like to know what I need. I swear it looks like its gm style...
Mine looks like the square gm one that pressed into the mount with clips. When I look at stock 69' photos my cable is stock. Do I need to order one for a gm cable? I just wanted an adjustable throttle bracket with dual return springs and for my cable to just pop into the square hole.
What cable type do 69's use? Because it is apparently not "Ford style" and I would like to know what I need. I swear it looks like its gm style...
06-17-2015, 04:28 PM
#69
4th Gear Member
Join Date: Nov 2013
Location: arizona
Posts: 1,398
ok, im not sure what your question is . . you can buy the stock bracket for the original throttle cable . . it has a square hole in it for the square piece on the cable.
if you want to make an adjustable cable, you need to make an adjustable cable bracket.
if you want to make an adjustable cable, you need to make an adjustable cable bracket.
06-18-2015, 12:53 PM
#70
I want an adjustable throttle bracket setup with dual return springs. I ordered one from AED that fit, except that it didn't accept the 69's throttle cable. I have been reading and discovered that I actually need one for a gm style cable. The type that 69's have is apparently a gm style cable. AKA square snap-in style throttle cable. I will be returning what I have and ordering another.