You could build your line out of stainless with a shorter hose, then do the same for the PCV.
348 Tri-Power Build gone wrong / Follow New Rebuild
- Thread starter '37-4D
- Start date
Yes you booth need and want that line.It appears to be a ported source for the vac.advance.A cleaner option as a winter project would be to source a hollow carb mounting stud from Show Cars and install it on the rt.rear of the rear carb.Then you can make a short hose from the stud to the advance and plug that port and lose that not so pretty cooper line.
'37-4D
Well Known Member
@Don Jacks Is this what you are referring to?
Is it as simple as removing one of the current rear carb studs and replace with this one then plug the rubber hose?
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'37-4D
Well Known Member
Alright!!!! she's all dyno'ed and good to go!!!!
Here is what I have to say prior to delivering the numbers:
This is an early '58 348 casting 872 block with 333 heads. She has the factory intake with 3 Rochester 2bbl carbs small base.
Now I've been told that a single 4bbl carb is the way to go to get the most out of these work horses, this from Carl McQuillen. Somewhere around 350 hp with that setup and upwards of that in torque if it was applied to my motor.
Also aside from the restrictive intake, I have exhausts that have been blocked for noise, evacuating through dumps at the rear of the cab. That takes away 10 hp as per dyno results.
So here it is: She made 288 hp and 327 ft/lbs torque. I expected more!!! @Don Jacks , we followed the recipe
However, what IS MOST IMPORTANT to me is reliability, dependability and the aesthetics of the tri setup, so beauty over power.
I think it's plenty for what I need it for. Won't be racing this thing, and I do want to drive it...a lot
Here are some pics and videos of the session. Had it booked for the day, performed 8 runs I believe. We tested open headers and closed through the rear dumps.
Overall, I am happy everything went well. I'll be happier once she's back were she belongs and drives without any issues!!
Here is what I have to say prior to delivering the numbers:
This is an early '58 348 casting 872 block with 333 heads. She has the factory intake with 3 Rochester 2bbl carbs small base.
Now I've been told that a single 4bbl carb is the way to go to get the most out of these work horses, this from Carl McQuillen. Somewhere around 350 hp with that setup and upwards of that in torque if it was applied to my motor.
Also aside from the restrictive intake, I have exhausts that have been blocked for noise, evacuating through dumps at the rear of the cab. That takes away 10 hp as per dyno results.
So here it is: She made 288 hp and 327 ft/lbs torque. I expected more!!! @Don Jacks , we followed the recipe
However, what IS MOST IMPORTANT to me is reliability, dependability and the aesthetics of the tri setup, so beauty over power.
I think it's plenty for what I need it for. Won't be racing this thing, and I do want to drive it...a lot
Here are some pics and videos of the session. Had it booked for the day, performed 8 runs I believe. We tested open headers and closed through the rear dumps.
Overall, I am happy everything went well. I'll be happier once she's back were she belongs and drives without any issues!!
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Tri-power intakes are much like #379 heads, just not performers but both of them look so cool!
Being an iron head engine, I wonder if the water temp was up to 185 to 195 degrees would make more power.
'37-4D
Well Known Member
Being an iron head engine, I wonder if the water temp was up to 185 to 195 degrees would make more power.
It will make aa little more after it's fully broken in.It's less than I thought it would be.I don't know how much if any bowl work was done when they went to the next size up valves either.Compared to what he had this thing's going to feel like a rocket..
'37-4D
Well Known Member
This from SuperChevydotcom:
"The first of the new Turbo Thrust 348 engines produced 250 horsepower. It had a Rochester 4GC four-barrel carburetor and pumped out 355 lb-ft of torque at 2,800 rpm. The second was a Super Turbo Thrust 348. It had three two-barrel carburetors and produced 280 horsepower at 4,800 rpm with 355 lb-ft of torque at 3,200 rpm."
I'm not sure if this is due to the fact that I have the earlier of the '58 blocks
"The first of the new Turbo Thrust 348 engines produced 250 horsepower. It had a Rochester 4GC four-barrel carburetor and pumped out 355 lb-ft of torque at 2,800 rpm. The second was a Super Turbo Thrust 348. It had three two-barrel carburetors and produced 280 horsepower at 4,800 rpm with 355 lb-ft of torque at 3,200 rpm."
I'm not sure if this is due to the fact that I have the earlier of the '58 blocks
'37-4D
Well Known Member
'37-4D
Well Known Member
I wasn't there in person. The shop guys went. Curious, what makes you think they didn't monitor the air fuel ratio?
If you don't mind please elaborating on where this is going for this newb to better understand LOL.
Do you think the carbs could be tuned better?
'37-4D
Well Known Member
I spoke with the dyno guys and they did not have Rochester jets to dial the carbs right in. Also they couldn't use their AFR meter because of my exhausts. I'll have to take it to a chassis dyno guy that can throw one in the dumps to get a reading. I am also due to see a carb guy that specializes in Rochester carbs. Not sure if I just made any sense
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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.