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Discussion Starter · #381 ·
That's my point . You need torque.
You got no torque from gear because you got no gear so it's all engine torque and you only have 2 gears .
You need to use every ounce of engine torque you have .

You're saying that torque drops off fast after 5 grand therefore you think shifting sooner is better .

But By doing that and falling back to 3400 on the shift you are coming out of first and starting in second with quite a bit less torque and hp than is available to you. Thats why I'd think youd want to stay in 1st as long as possible because gear is what you lack .
When you are higher up in rpm you have rpm and hp is climbing on your side .

Look at the dyno .
Instead of starting out in second at 3400 and 565 torque and a measly 360 hp why not start out in second at 4 grand with 600 torque and your 450 hp at that point which will pull the big heavy load with no gear out of it's own way and get into the available horsepower versus running 1st gear to 360 hp .That way youd see close to max hp at then end of the show .
Just my 2 cents.
I could be wrong but I'd certainly try it .
Nothing to lose
Looking at the dyno sheet, I’d agree with you…but that’s not what my buttometer tells me at the moment. So, what would make the power fall off noticeably after 5300?

I’m going to pull the valve covers and inspect the valve stem tips to ensure I don’t have any valves floating, but I’m betting it’s fuel supply, and I’m not talking about the 750 cfm carb. Bumping up to 1/2” fuel line is probably a priority at the moment.

I have the RobMC pickup, I need to pick up a roll of 1/2 aluminum line, assuming it works with today’s garbage fuel.
 

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I don’t know if changing the fuel lines is going to net anything. My son and I ran 10’s with 3/8” line and a mechanical fuel pumps with composite rods.
My sons fuel pump was a autozone replacement pump!
Stock tank and pick up.
950 DP carb.
He dyno’d at 601/560.
 

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Discussion Starter · #383 ·
I don’t know if changing the fuel lines is going to net anything. My son and I ran 10’s with 3/8” line and a mechanical fuel pumps with composite rods.
My sons fuel pump was a autozone replacement pump!
Stock tank and pick up.
950 DP carb.
He dyno’d at 601/560.
Check his fuel lbs/hr, for comparison - above 5300, mine is >250 lbs/hr. Of course, the power was faltering above this rpm on the dyno, whether it was float or windage. From the weight and mph, I suspect I’m making much closer to 600 than dyno day showed.

First thing I need is a tach to verify at what rpm the fall off occurs, it’s possible the converter is slipping more than I think. If truly falling off after 5300, there must be an explanation. I trust my butt when it comes to knowing when to shift.
 

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Discussion Starter · #385 · (Edited)
Stock converters are “usually” pretty tight.
I’ll take a look for his sheet to see the lbs per hr. Are you using a stock steel fp rod?
Yes, but it’s not like I’m high rpm.

it might sound strange, but I didn’t notice it flattening out at the big end.
 

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Stock converters are “usually” pretty tight.
I’ll take a look for his sheet to see the lbs per hr. Are you using a stock steel fp rod?
Was it nosing over on the top end?
When tight or loose is referred to in reference to converters is that a reference as to slippage ?
Like
Tight = less slip
Loose = more slip ??
 

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Looking at the dyno sheet, I’d agree with you…but that’s not what my buttometer tells me at the moment. So, what would make the power fall off noticeably after 5300?

I’m going to pull the valve covers and inspect the valve stem tips to ensure I don’t have any valves floating, but I’m betting it’s fuel supply, and I’m not talking about the 750 cfm carb. Bumping up to 1/2” fuel line is probably a priority at the moment.

I have the RobMC pickup, I need to pick up a roll of 1/2 aluminum line, assuming it works with today’s garbage fuel.
That might be it man .
No tach .
You are guessing you are falling back to 3400 rpm but maybe you are indeed falling back to 3800 or 4 grand where torque is greater .
If that's the case then I think you're about all done here without changing somthing else.
You need a tach lol

And if you look at the dyno power isnt falling off at 5300 .
Power peaks at 6 grand .
Torque falls off at 52 like it allways does .

In first gear seat of pants will tell you that the rate of the engine torque pulling is falling off
At somewhere around 5 grand as it should/will BUT youve got the car moving at that point and your power is still increasing and you still have rpm and gear on your side .
Run that sucker up to 6300 while you've got gear and maximize the available hp.

Then when you shift your gonna get a pretry big drop in rpm because of the tall gear and BOOM ! Your right back in the biggest torque the engine makes when you lose gear on the shift . 11.999. Lol

Honestly with those cubes I'd have wanted to see atleast 650 torque especially in this scenario . Maybe that had to do with a budget restraint. IDK
 

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Yes. Tight less slip. Now large engines or ones that make a ton of torque will or can raise rpm of converter.
Thats what I thought .
More torque is more load.
Tall gear is more load.
More load = higher stall
 

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As mentioned, regular parts store Type F will work, and it will tighten up the converter, increase efficiency. You don't have any flash stall to speak of really, so making it transfer power better for even more mph gain may help, and would be the route I would take.
Did you adjust your engine oil level? In Mark's modified Moroso pan I have ran 5 quarts total with zero oil pressure issues. WIX 51061 filter.

If you don't have a lightweight fuel pump pushrod, you should have one. Howards composite #94475.

Without the aggressive launch, you need to make up time in making MPH. Takes power and efficiency to do that. Confirm carb throttle blades are 90 degrees to the throttle bores at full throttle, which may take some filing on the baseplate to allow the primary to do so, and bending of the link rod for the secondary.

What mufflers do you have, or did you post that already?
 

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Looking at the dyno sheet, I’d agree with you…but that’s not what my buttometer tells me at the moment. So, what would make the power fall off noticeably after 5300?

I’m going to pull the valve covers and inspect the valve stem tips to ensure I don’t have any valves floating, but I’m betting it’s fuel supply, and I’m not talking about the 750 cfm carb. Bumping up to 1/2” fuel line is probably a priority at the moment.

I have the RobMC pickup, I need to pick up a roll of 1/2 aluminum line, assuming it works with today’s garbage fuel.
Would be interesting to see if your combo would pickup with an 850 SV over the 750 version.
 

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Discussion Starter · #392 ·
That might be it man .
No tach .
You are guessing you are falling back to 3400 rpm but maybe you are indeed falling back to 3800 or 4 grand where torque is greater .
If that's the case then I think you're about all done here without changing somthing else.
You need a tach lol

And if you look at the dyno power isnt falling off at 5300 .
Power peaks at 6 grand .
Torque falls off at 52 like it allways does .

In first gear seat of pants will tell you that the rate of the engine torque pulling is falling off
At somewhere around 5 grand as it should/will BUT youve got the car moving at that point and your power is still increasing and you still have rpm and gear on your side .
Run that sucker up to 6300 while you've got gear and maximize the available hp.

Then when you shift your gonna get a pretry big drop in rpm because of the tall gear and BOOM ! Your right back in the biggest torque the engine makes when you lose gear on the shift . 11.999. Lol

Honestly with those cubes I'd have wanted to see atleast 650 torque especially in this scenario . Maybe that had to do with a budget restraint. IDK
I’ll put a tach in to sort it out.

I’d say any lack torque has to do with 2-1/8” dyno headers, self-ported heads, and cam ground for the smoother idle, than budget constraints. It’s not lacking much.
 

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Discussion Starter · #393 ·
As mentioned, regular parts store Type F will work, and it will tighten up the converter, increase efficiency. You don't have any flash stall to speak of really, so making it transfer power better for even more mph gain may help, and would be the route I would take.
Did you adjust your engine oil level? In Mark's modified Moroso pan I have ran 5 quarts total with zero oil pressure issues. WIX 51061 filter.

If you don't have a lightweight fuel pump pushrod, you should have one. Howards composite #94475.

Without the aggressive launch, you need to make up time in making MPH. Takes power and efficiency to do that. Confirm carb throttle blades are 90 degrees to the throttle bores at full throttle, which may take some filing on the baseplate to allow the primary to do so, and bending of the link rod for the secondary.

What mufflers do you have, or did you post that already?
I don’t really want to tighten up my converter any more, do I?

Engine oil is down to 6 qts. I’ll go back with 5.5 qts when I change it.

Thanks for the details on the fuel pump pushrod.

Throttle blades are good.

70 Series Flowmaster. 3”
 

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I’ll put a tach in to sort it out.

I’d say any lack torque has to do with 2-1/8” dyno headers, self-ported heads, and cam ground for the smoother idle, than budget constraints. It’s not lacking much.
What headers you got on it ?
 

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I don’t really want to tighten up my converter any more, do I?

Engine oil is down to 6 qts. I’ll go back with 5.5 qts when I change it.

Thanks for the details on the fuel pump pushrod.

Throttle blades are good.

70 Series Flowmaster. 3”
Would a tighter converter cause the rpm to drop less on the upshift ?
Looking at that torque curve I'd think youd want it to drop more not less
 

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From what I’ve “read” (I like to use quotes) lol you mufflers may be a restriction.
The times in my sig are with a full exhaust with reducing x pipe 3 down to 2.5” pipe to 2.5” ultra flows with 2.5” tailpipes behind wheel. We’re not fans of dropping exhaust to run it at the track.
We run them the way we run them on the street.
My sons Malibu has a full 3” x pipe,mufflers and tails. 1-7/8 headers
 

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Discussion Starter · #399 ·
So 1/8 smaller than what was used on the dyno .
Does smaller diameter header usually = more low torque ?
Yes.

I’d say that’s a pretty safe bet, however I’d defer to those with more dyno testing experience. I’ve always read that 1-7/8” primary tubes produce more low end torque than 2” tubes. I’d assume the same is true when considering 2-1/8” vs. 2”.
 

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Discussion Starter · #400 ·
From what I’ve “read” (I like to use quotes) lol you mufflers may be a restriction.
The times in my sig are with a full exhaust with reducing x pipe 3 down to 2.5” pipe to 2.5” ultra flows with 2.5” tailpipes behind wheel. We’re not fans of dropping exhaust to run it at the track.
We run them the way we run them on the street.
My sons Malibu has a full 3” x pipe,mufflers and tails. 1-7/8 headers
I’ve read the same when it comes to Flowmaster mufflers, but the 70 Series mufflers sound great, and this is a cruiser, not a race car. I’ve thought about going to 2.5” tailpipes, simply to save weight, but this Torque Tech system is a thing of beauty and I can’t imagine changing it.
 
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