Looking for more pep off the line

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Alecb said:
I'm a fan of the Engine Masters show, having a good tune is important for making power and optimizing an engine. I'm a novice at tuning but I'm doing my best to learn how to become better.
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Tune up and tuning for performance are entirely different. Tuning for performance goes above and beyond a standard tune up. I know by how you are responding that you already know that, I just wanted to reiterate. Performance tuning can mean the difference between a dead dog and a total tire melter. I can take a stone stock 318 two barrel and add gobs of power through performance tuning and not change one single "big" part.
 
Mattax said:
Hence the need to measure the timing vs rpm.

I hear ya though. Skipping that step and going blind into 4000 rpm plus at full load would be super risky.
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Let's bring this back to a strategy that I would recommend for this situation.
Limiting the advance shouldn't be needed because 3000+ rpm tuning should be put aside until the foundation is put on solid footing. That said, we know some people just can't resist their urge to floor it.... so this assumes Alecb, you have the patience and interest in solving first problems first.

First problems here are:
a. Some fault in charging system (that can be worked on with the current tune just as it is)

b. Idle and off-idle needs performance tuning and testing. (that can be worked on with the distributor as it is as long as that includes timing vs rpm measurements. Without those, then after making internal changes to the distributor you will be starting from scratch). You can drive it on the local streets, but avoid flooring it or high speed stuff.
 
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Alecb said:
My converter stall is 1600-2000, it's listed as street/strip. I do have a thermoquad I was considering rebuilding and putting on my engine, I believe it's 800 cfm.
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That is not a street strip or even a performance converter since many factory converters were in the 2000 - 2500 stall range.

There are big and small primary TQ carbs. If your primary is 1/5, that’s the big TQ, at 1.38, it’s the small TQ.
Alecb said:
I'm currently running manifolds, I have power steering on my car and it looks like it would be a big fight to get headers on there. Eventually, I would like to get a set of Doug's headers when the budget permits it. The summit cam I'm running was on sale which is partly why I bought it, I wasn't sure what to get as this is my first engine build so I stuck with something close to stock. Might have to go with a Comp XE268 or something later.
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Headers are a bit of a PIA no matter what brand or tube diameter. I’ve owned two 1973 Duster with P/S and both had headers and not a huge item to contend with. Actuality, it’s not even an issue at all.

I also wouldn’t use that cam so fast as the whole engine package is a balancing act and that cam should not be blindly thrown in.
Alecb said:
I appreciate your detailed write-up on tuning. That drillbit trick is genius, I would not have thought of that.
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It’s amazing who knows what here along with some really slick tricks.
RustyRatRod said:
I think they're getting you off track already. IMO, you should optimize what you HAVE. A camshaft change is not going to magically unlock 50HP down low. But good tuning might. I would wait on any big changes. But, it's not my money or car so do what you want with it and good luck.
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Correct! 50hp will never be seen. I’d bet $500 on 50 lbs or tq if he follows what I say to do and he only got half with a camshaft recommendation. ****! Name the guy to hold my $500 bucks for this bet.
 
I agree, there's a LOT of room for improvement with the converter. It's really not even up to par with a stock 340 converter. That said, there's a lot of room left in the tune, too. That's where I would start.
 
Food for thought on the LSA debate:

Shout out to Mike Jones 2!!

Mike did a cam for it was we totally went against the "norm." It was a 55 tool steel, less duration, more rocker, and way wider LSA...

Some folks I knew were worried about no torque, etc..
 
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There's room for improvement everywhere on any build. Best to start with the basics and tune what you have and when the limitations are found change parts but until then persevere with what you already have. A lot can be improved with just advance curve work (timing) and carb (fuel)

What spark plugs are you using and what gaps are they set at.
How do they look?
Does it hesitate or bog or run rough anywhere in the RPM range?
What fuel?

Forget about spending any money first make sure you have the basics ironed out (Air Fuel Ignition) before grabbing the wallet.
 
RustyRatRod said:
I agree, there's a LOT of room for improvement with the converter. It's really not even up to par with a stock 340 converter. That said, there's a lot of room left in the tune, too. That's where I would start.
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Hysteric said:
There's room for improvement everywhere on any build. Best to start with the basics and tune what you have and when the limitations are found change parts but until then persevere with what you already have.
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Hysteric said:
Forget about spending any money first make sure you have the basics ironed out (Air Fuel Ignition) before grabbing the wallet.
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Best advice and a plan for a direction that should be taken written above.
 
Saw a full bodied street car with a 318 weighing 3400 lbs at least run mid 12's with a low 60ft with only a 2500 converter and 3.23 gear. Did I mention the guy is a tuner......

Tune what you have it will only get better but it will take time.
 
When the cam was changed, wonder if the timing gears were "dot to dot". Could be the cam is retarded?
 
Hysteric said:
There's room for improvement everywhere on any build. Best to start with the basics and tune what you have and when the limitations are found change parts but until then persevere with what you already have. A lot can be improved with just advance curve work (timing) and carb (fuel)

What spark plugs are you using and what gaps are they set at.
How do they look?
Does it hesitate or bog or run rough anywhere in the RPM range?
What fuel?

Forget about spending any money first make sure you have the basics ironed out (Air Fuel Ignition) before grabbing the wallet.
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I'm using Champion sparkplugs, I believe I gapped them 0.035. Last time I looked they seemed to be burning normally, the porcelain was a dirty tan color. No real bogs or hesitations when driving, though the car is a little finicky when cold but that's normal right? I have 89 octane in the tank, but I live in California so our gas isn't the best.
 
Alecb said:
Yeah, I did the dot to dot when I put the engine together. Kinda wishing I had degreed the cam.
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Have you done a cranking compression test? Leakdown test?
 
Alecb said:
The best way I can describe it is I have to lay into the pedal to get going from a stop. Now I'm not looking for wheelies or a fast 60-foot on this car, I just think a V8 car should have some more pep. I am a novice when it comes to tuning so that is probably part of the issue.
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This sounds like it could be a trans issue. A 360 in that car should leap off the line when a fly farts on the gas pedal.
Maybe as simple as a kickdown or shift linkage adjustment
 
65TerrorCuda said:
This sounds like it could be a trans issue. A 360 in that car should leap off the line when a fly farts on the gas pedal.
Maybe as simple as a kickdown or shift linkage adjustment
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My transmission seems to shift fine, I could reset the kick down cable.
 
One of the very first things you should do is make sure that the throttle is opening all the way when you push it to the floor.
 
Alecb said:
I haven't, should I do that with this being a fresh rebuild? It probably has 65 miles on it.
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Your engine isn't fully broken in yet and yes I'd do a compression test doesn't hurt to know.
Did you breakin cam on 1st start ?

I'd make a list of things to check in a order that makes sense

eg.. start with, make sure carb goes full throttle, compression test, ignition, carb tuning etc..
 
Also make 100% SURE the brakes aren't dragging. 100%. Not 99%.
 
Just because your engine is fresh doesn't mean it's making good compression. It could have any number of problems. Do a compression test on all 8 cylinders and report back the numbers.

Stop talking about spark plug gap or spark plug brand that isn't getting you anything.

That converter isn't doing you any favors, especially combined with the cam.

You're giving up probably 20 ft lbs or more with the exhaust manifolds.

Do get the ignition wired correctly.

Watch this video: it gives a good breakdown of what can easily be achieved with a very mild 360 combo. This engine would have no off the line issues.
 
273 said:
Your engine isn't fully broken in yet and yes I'd do a compression test doesn't hurt to know.
Did you breakin cam on 1st start ?

I'd make a list of things to check in a order that makes sense

eg.. start with, make sure carb goes full throttle, compression test, ignition, carb tuning etc..
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I did break in the cam on the first start. I'll report back with compression numbers.
 
Mean416 said:
Just because your engine is fresh doesn't mean it's making good compression. It could have any number of problems. Do a compression test on all 8 cylinders and report back the numbers.

Stop talking about spark plug gap or spark plug brand that isn't getting you anything.

That converter isn't doing you any favors, especially combined with the cam.

You're giving up probably 20 ft lbs or more with the exhaust manifolds.

Do get the ignition wired correctly.

Watch this video: it gives a good breakdown of what can easily be achieved with a very mild 360 combo. This engine would have no off the line issues.
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Wow, that video has great information, I wish I had watched it before I dropped my 360 in the car. I don't like the manifolds, but they fit and I had them. I will upgrade to headers, most likely a set of Doug's since they look like they fit decent with power steering. The power steering box and having to run the headers through the steering linkage turned me away from the cheaper headers.
 
Alecb said:
Wow, that video has great information, I wish I had watched it before I dropped my 360 in the car. I don't like the manifolds, but they fit and I had them. I will upgrade to headers, most likely a set of Doug's since they look like they fit decent with power steering. The power steering box and having to run the headers through the steering linkage turned me away from the cheaper headers.
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The cheap Summit headers fit with power steering. Unless you're going to run your front end low and in the weeds, they will work fine. I've run several sets bent like those and the Hedmans and the only thing I had to do was take a pry bar and tweak the two tubes on either side off of the torsion bars, because they rattled against them. All the guys will run them down, but they work well as long as you sit at stock ride height with stock height tires.
 
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