348 Tri-Power Build gone wrong / Follow New Rebuild

'37-4D

'37-4D

Well Known Member
Don Jacks said:
Nothing to worry about here.That smoke is from the fuel mixture being rich at acceleration.This is caused by the accelerator pumps being engaged at the same time.This can be fixed by fooling with the pump squirter size or accelerator pump travel.No more than it's puffing,leave it alone.
Click to expand...
Yes that's what the guy said.
 
1964SuperStocker

1964SuperStocker

Well Known Member
Supporting Member 3
Outside of a simple break in I hate to say the numbers aren't worth much. If you don't know what your air/fuel mix is like at any point in a pull (in relation to timing) then it could be anything. I witnessed 3 weeks ago a guy pull up his race car to a chassis dyno, hooked up oxygen sensor and checked timing. Carb was rich and timing had to be adjusted and they added a better air cleaner base plate and for $250 the dyno tune found 57hp. This guy had run this car all season and took 3rd in points and if he would have had that extra 57hp my guess is he would have a bigger pay check and trophy to show for it.
 
'37-4D

'37-4D

Well Known Member
1964SuperStocker said:
Outside of a simple break in I hate to say the numbers aren't worth much. If you don't know what your air/fuel mix is like at any point in a pull (in relation to timing) then it could be anything. I witnessed 3 weeks ago a guy pull up his race car to a chassis dyno, hooked up oxygen sensor and checked timing. Carb was rich and timing had to be adjusted and they added a better air cleaner base plate and for $250 the dyno tune found 57hp. This guy had run this car all season and took 3rd in points and if he would have had that extra 57hp my guess is he would have a bigger pay check and trophy to show for it.
Click to expand...
:good
 
  • Like
Reactions: Tim
1964SuperStocker

1964SuperStocker

Well Known Member
Supporting Member 3
We all love these motors for their looks more than performance and reliability. They can be made to perform and be reliable but its not as cheap and easy as a sbc or bbc. If you were driving my wagon it may not seem like much power but my wagon will be close to 5000lbs when I finish putting it together. Your car doesn't weight much so you will have way more power to weight ratio than most cars out there. Pretty exciting and with a proper tune I bet you pull more power. Especially because you have good valves, good springs, camshaft and pistons. Get an oxygen sensor on those headers and adjust your carbs/timing accordingly on a chassis dyno and I'm certain you will squeeze more out of it.
 
'37-4D

'37-4D

Well Known Member
1964SuperStocker said:
We all love these motors for their looks more than performance and reliability. They can be made to perform and be reliable but its not as cheap and easy as a sbc or bbc. If you were driving my wagon it may not seem like much power but my wagon will be close to 5000lbs when I finish putting it together. Your car doesn't weight much so you will have way more power to weight ratio than most cars out there. Pretty exciting and with a proper tune I bet you pull more power. Especially because you have good valves, good springs, camshaft and pistons. Get an oxygen sensor on those headers and adjust your carbs/timing accordingly on a chassis dyno and I'm certain you will squeeze more out of it.
Click to expand...
In my close traditional Hot Rod circle, there is a lot of resistance to chassis dyno. Simply put they just don't like it :dunno2. And then there are all the discrepancies that come with, see article given to me by a veteran rodder. I am therefore reluctant and wonder if it's really worth it. I definitely do want my carbs to be jetted + tuned to their full potential, and I'd rather take my chances with my guy who specializes in Carbs (especially Rochesters conversions + rebuilds) and let him have a go. He is currently putting together a 3x2 setup for me for a sbc motor for another project. Rebuilding the outer carbs to work progressive. By the time I get it back it is built, tuned, tested and ready to plug in. I spoke with him this morning and funny enough he is currently working on a 348 3x2 setup for a client. This most likely won't happen until spring.

https://www.hotrod.com/articles/hrdp-0405-chassis-dyno-guide/
 
'37-4D

'37-4D

Well Known Member
I have good friends. Motor back in!!!

0eXQdyb.jpg
TLLnmzU.jpg
l4IkjDy.jpg
PWfkaKJ.jpg
GUprnGh.jpg
2f7gqd9.jpg
xKmMhqx.jpg
hka1u3J.jpg
 
1964SuperStocker

1964SuperStocker

Well Known Member
Supporting Member 3
'37-4D said:
In my close traditional Hot Rod circle, there is a lot of resistance to chassis dyno. Simply put they just don't like it :dunno2. And then there are all the discrepancies that come with, see article given to me by a veteran rodder. I am therefore reluctant and wonder if it's really worth it. I definitely do want my carbs to be jetted + tuned to their full potential, and I'd rather take my chances with my guy who specializes in Carbs (especially Rochesters conversions + rebuilds) and let him have a go. He is currently putting together a 3x2 setup for me for a sbc motor for another project. Rebuilding the outer carbs to work progressive. By the time I get it back it is built, tuned, tested and ready to plug in. I spoke with him this morning and funny enough he is currently working on a 348 3x2 setup for a client. This most likely won't happen until spring.

https://www.hotrod.com/articles/hrdp-0405-chassis-dyno-guide/
Click to expand...
Fun fact. You have a direct comparison which you could specifically compare your engine dyno and your chassis dyno against each other. Should you choose to do a chassis dyno then you would know the exact amount of drag your drive train creates (useful information). More importantly in your specific situation a chassis dyno is a real world power situation where any adjustment can been seen quickly. I would say using an engine dyno exclusively is for people who like to say big numbers but are to scared to talk about what they engine will actually put to the ground in their specific car. All you want to know is what kind of gain can be had. Take your set up now before your buddy does his magic on it and see what can be found on a chassis dyno. Basically the car I saw 3 weeks ago in the Chassis dyno started out with a base line. Then they found an extra 57hp for $250 with taxes. Finding/Getting that kind of hp for $250 is unheard of because you can't bolt anything on the engine for that price and come up with those kinds of numbers. Another thing is, your tri-power carb guy is going to charge you more than $250 to do some magic but is he going to do his magic and then throw this engine on a dyno to prove he actually improved anything? He might vastly improve your bottom end response but kill your top end performance. Are you ready to accept whatever results he creates because unless he uses the same dyno you pulled the motor off of and does his magic on the carbs then you can only guess what results he has created. If you aren't going to get a couple oxygen sensors mounted on your headers and run this engine knowing your actual air/fuel mix then you are simply throwing money at a perceived problem without specifically knowing the results making anyone touching your tri-power set up a complete waste of money and time. You dyno'd with an incomplete baseline due to no oxygen sensors and now it runs pretty good but you are going to put more money towards it with no oxygen sensors and no engine dyno? I would stop chasing hp ghosts and get some sensor bungs welded to the bottom side of those headers and get that engine back on the dyno if the engine performance is actually an issue in your mind. It will save you more money, time (and most importantly piece of mind that it is specifically performing at its best) by not putting that engine back in the car. Unless there is a time issue for a show you have to attend this winter or something. Good luck, I just hope you don't get stuck chasing more power because without specifically knowing your air/fuel ratio then nothing else matters. Nothing.
 
'37-4D

'37-4D

Well Known Member
1964SuperStocker said:
Fun fact. You have a direct comparison which you could specifically compare your engine dyno and your chassis dyno against each other. Should you choose to do a chassis dyno then you would know the exact amount of drag your drive train creates (useful information). More importantly in your specific situation a chassis dyno is a real world power situation where any adjustment can been seen quickly. I would say using an engine dyno exclusively is for people who like to say big numbers but are to scared to talk about what they engine will actually put to the ground in their specific car. All you want to know is what kind of gain can be had. Take your set up now before your buddy does his magic on it and see what can be found on a chassis dyno. Basically the car I saw 3 weeks ago in the Chassis dyno started out with a base line. Then they found an extra 57hp for $250 with taxes. Finding/Getting that kind of hp for $250 is unheard of because you can't bolt anything on the engine for that price and come up with those kinds of numbers. Another thing is, your tri-power carb guy is going to charge you more than $250 to do some magic but is he going to do his magic and then throw this engine on a dyno to prove he actually improved anything? He might vastly improve your bottom end response but kill your top end performance. Are you ready to accept whatever results he creates because unless he uses the same dyno you pulled the motor off of and does his magic on the carbs then you can only guess what results he has created. If you aren't going to get a couple oxygen sensors mounted on your headers and run this engine knowing your actual air/fuel mix then you are simply throwing money at a perceived problem without specifically knowing the results making anyone touching your tri-power set up a complete waste of money and time. You dyno'd with an incomplete baseline due to no oxygen sensors and now it runs pretty good but you are going to put more money towards it with no oxygen sensors and no engine dyno? I would stop chasing hp ghosts and get some sensor bungs welded to the bottom side of those headers and get that engine back on the dyno if the engine performance is actually an issue in your mind. It will save you more money, time (and most importantly piece of mind that it is specifically performing at its best) by not putting that engine back in the car. Unless there is a time issue for a show you have to attend this winter or something. Good luck, I just hope you don't get stuck chasing more power because without specifically knowing your air/fuel ratio then nothing else matters. Nothing.
Click to expand...

What you are saying here makes complete sense to me. I was given a trusted contact today that can chassis dyno my truck for around that price here in Canadian dollar. Will hook up oxygen sensor an throw an AFR meter in the dump pipe. I hope I just repeated my phone conversation properly haha. I'm highly considering it. Says he can most likely discover something on the first pull. He's close to where I live too which is a bonus!!
 
DonSSDD

DonSSDD

Well Known Member
Supporting Member 2
Even if you don’t find a lot more hp, getting your 348 running as efficiently as possible via the dyno tuning is worth having. Running lean or rich, getting carbs and timing right, will be worth it.

The more hp you find will typically be at higher rpm, worth doing if a racer for sure, but having it start easy and run good in the usable rpm range is what you’ll appreciate most on this truck.

Hope you’ll have it out on the road today, good luck. It’s an eye catcher.
 
You must log in or register to reply here.
Top