Need some advice

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Tool505

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Got my car up and rolling and feels pretty slow. It's running good and smooth but I expected more. Tell me if you see anything wrong with the combo and I'll also upload my cam sheet.

Magnum 360
Eq heads drilled for la intake ( believe they are 1.92/1.6)
1.5 roller rockers
Hydraulic roller cam
Kb 107 flat top Pistons
Eagle rods
Stock crank
Rpm airgap intake
Edelbrock 650
Edelbrock fuel pump ( mech )
323 rear end with 3 speed man. Trans
Headers
2.5 exhaust
Orange box ignition
Summit street distributor
 

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Tool 505,

Oh Man.

Your going to need some Gears with that Camshaft.

With 3.23's as your Cogs,

That's like listening to 'Communication Breakdown' with the Volume set at '1'.

And that 3-Speed Manual sure isn't helping matters either.
 
Yeah that's what everyone was leaning towards last time justwanted to throw in my cam sheet for reference this time. Right now she goes down the hwy pretty good at 75. I'll have to check rpm. If I could still go 60 on the hwy with not rapping it up to high Id be happy . Is that feasible with 3.91 rear and would I still have enough top end for a quarter mile pass
 
How does it do when you punch it at about a hundred? I had a car once with 2.88's and a three speed. I went into high at about a hundred and it did real well.
 
Tool505 said:
Yeah that's what everyone was leaning towards last time justwanted to throw in my cam sheet for reference this time. Right now she goes down the hwy pretty good at 75. I'll have to check rpm. If I could still go 60 on the hwy with not rapping it up to high Id be happy . Is that feasible with 3.91 rear and would I still have enough top end for a quarter mile pass
Click to expand...

Tool 505,

What is the size of your Rear Tires.
 
235/60/15, haven't had it up to 100 yet. She's perky but doesn't feel alive. I cam drop the clutch in first at a roll and she will light em up and go sideways but falls just isn't as quick as I expected
 
Tool505 said:
235/60/15, haven't had it up to 100 yet. She's perky but doesn't feel alive. I cam drop the clutch in first at a roll and she will light em up and go sideways but falls just isn't as quick as I expected
Click to expand...

Tool 505,

One more question.

Which 3-Speed Manual Transmission is in there ....

Could it be with the Gear Ratio's of
1st ....... 2.55
2nd ...... 1.49
3rd ....... 1.00
 
The 3 speed is OK at best. Worry about that later.
Install a set of gears. The 3.91's mentioned should be good.
Everything else is in the tune of the engine. The set up looks good for a nice street car.

I'm not really a fan of the Orange box. I like the Chrome or FBO box. Recheck and curve your distributor. Make sure your carb is well tuned. Primary and secondary.
 
With a starter gear of 3.23x 2.55=8.24, yours will for sure be soft on take off. But from 2800/25mph or so,if the rest of the combo is well tuned, it should be getting it on. EDIT By well tuned,we are talking firstly, the ig timing, then the carb, and lastly the cam timing.The rest of the combo looks pretty good.
That combo,if sharp EDIT (well-tuned) will like a starter gear of around 9.5 to10: if lazy will want 11 or more. The 10:1 is a 3.09x3.23,or a 2.66x 3.55. The 11:1 is a 3.09x3.55, or a 2.66x4.10
From here it becomes an exercise of expectations.
The very first thing I would do is a compression test.
If the pressure is way up there,its gonna get expensive. If its in the basement, a simple cam swap can work wonders.
I have a similar engine-combo.
I had a 292/509Mopar cam for a while (very similar to your cam). Made a bunch of power when revved past 5500.Sounded fantastic. Scared passengers.It was too big for street.I sold it.
The next cam I swapped in was a [email protected] cam would pull an 8/1(2.66x2.94s) starter gear no problem, and smoke 275s. Now I had torque, right where I needed it. The only thing I miss about that big 292cam is the rumpity-rumpity.But this 223* cam dropped 2 lobes, so;
Currently I have a 232@050. This is a bit lazier out the gate, requiring a 10/1 minimum starter gear,So,I bought a GV and use an 11/1 starter gear which is 3.09x3.55. The GV reduces the 3.55s to 2.77,for highway cruising.I kinda miss that 223cam.Boy that 3.09Direct 4th gearset is hard to top with a GearVendor behind it.
Static compression ratio is a usefull number, no doubt, but cylinder pressure is a much better indicator.

So on to measuring the cylinder pressure.
 
Your trannie has a very tall 1-2 step and the rear is low, so the engine has to have a very wide RPM range in terms of percentage RPM range (not max-min RPM's, but max/min RPM's). You won't have that wide RPM with this long cam duration.

You'll always be suboptimum with the 3 speed manual so another option is a 4 speed to reduce the % gear change steps in the gears and does not demand as wide a % RPM range. You might end up pretty good with that, a shorter cam duration for sure, and (IMO) a gear in the 3.55 range to keep the RPM's down at 75 MPH on the highway. For me personally, the 3.91 would be too high revving for the highway. (And, of course, an auto trans has the feature of not needing as wide a % RPM range with even just a mildly higher stall TC.)

Do you know your advance curve numbers? Is this car/engine mainly for the street?
 
Not a single question about the timing until post #12?

Initial and total setting, with no vac advance attached?

Tire is only ~26" tall.
 
crackedback said:
Not a single question about the timing until post #12?

Initial and total setting, with no vac advance attached?

Tire is only ~26" tall.
Click to expand...

Again,

You're assuming the OP has no clue on Timing.

He stated that the car is running both 'good and smooth'. And that at
75 MPH the engine is cranking fine.

He just expected 'more' from the Engine.
 
^^post #12, nm9
All the starter gear ratios I mentioned in post#10, are 4-gear ratios, and the reason is per post #12.

Some of us clued into the 3-gear handicap right off.
That cam could make peak power at well past 5500, probably nearer to 5800. but lets take 5600 for sake of arguement . And lets apply this to the 1-2 shift only.With a 3-gear stick, it will want to be shifted at around 6800 or more , to drop in at 3975. Thats a short-shifted powerband requirement of 2825.I dont think they make an LSA wide enough to get out of that hole,in any kind of hurry with 323s.
If it had a 4-gear in it, it could be outshifted at 6500, and drop in at 4680(266low),presenting a well centered powerband of just 1820. Which will work with the 107 LSA
But since most guys are gonna short-shift at 6000 or 6200, that puts the drop-in around 3500.Can you spell SLUGGISH.
No timing in the world will wake that up.
 
So if it pulls off the bottom dead rich because the timing is a mile off, that won't matter? No stacking issues... Got it.

Don't forget the distance you lose on every gear shift.

Good luck with this one.
 
AJ/FormS said:
^^post #12, nm9
All the starter gear ratios I mentioned in post#10, are 4-gear ratios, and the reason is per post #12.

Some of us clued into the 3-gear handicap right off.
That cam could make peak power at well past 5500, probably nearer to 5800. but lets take 5600 for sake of arguement . And lets apply this to the 1-2 shift only.With a 3-gear stick, it will want to be shifted at around 6800 or more , to drop in at 3975. Thats a short-shifted powerband requirement of 2825.I dont think they make an LSA wide enough to get out of that hole,in any kind of hurry with 323s.
If it had a 4-gear in it, it could be outshifted at 6500, and drop in at 4680(266low),presenting a well centered powerband of just 1820. Which will work with the 107 LSA
But since most guys are gonna short-shift at 6000 or 6200, that puts the drop-in around 3500.Can you spell SLUGGISH.
No timing in the world will wake that up.
Click to expand...

This ^^^^ is good information.........:burnout:

That 'Comp-Cams' #HR-107 has an Overlap of 91*, and with an
early Intake opening.

That is a generous Overlap, so the 'Idle' should be a bit rough.

You need some Gears.
'Moser Engineering' makes a set of 3.73 Gears {489 Case > 8 3/4" Ring - 1 3/4" Pinion}, and that would allow that Camshaft to WORK much better,
and not destroy highway driving.
 
Sounds like gears and double checking timing is the key. What would you suggest for initial and total timing
 
As much initial as it will take without kicking back the starter when engine is up to temp. Total on sbm is any where from 32-38, but most end up around 34 or so. Need to have all timing in between 2000-3000, get it in as fast as possible without pinging. This is all done with out vacuum advance also. That can be tuned in after initial and total is done. My 340 is at 18 initial with 34 total, all in at 2800rpm, no vacum advance.
 
I am about 98% completed with a similar drivetrain replacement. Private message sent.
 
I'm pretty certain it was an oversight. We all know we should not run a cam like that on worn out stock valve springs.
 
gtsdude said:
As much initial as it will take without kicking back the starter when engine is up to temp. Total on sbm is any where from 32-38, but most end up around 34 or so. Need to have all timing in between 2000-3000, get it in as fast as possible without pinging. This is all done with out vacuum advance also. That can be tuned in after initial and total is done. My 340 is at 18 initial with 34 total, all in at 2800rpm, no vacum advance.
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More Good Information Above ^^^^^........:burnout:.
 
Alright I got some 3.91s put in her, she definitely woke up but I want more. What would be my best bet for my next power adder





Tool505 said:
Got my car up and rolling and feels pretty slow. It's running good and smooth but I expected more. Tell me if you see anything wrong with the combo and I'll also upload my cam sheet.

Magnum 360
Eq heads drilled for la intake ( believe they are 1.92/1.6)
1.5 roller rockers
Hydraulic roller cam
Kb 107 flat top Pistons
Eagle rods
Stock crank
Rpm airgap intake
Edelbrock 650
Edelbrock fuel pump ( mech )
323 rear end with 3 speed man. Trans
Headers
2.5 exhaust
Orange box ignition
Summit street distributor
Click to expand...
 
2.02 ported heads
Better cam, more lift
(Choose duration to fit the RPM needs,
Choose lift based on head flow,
Lift the valve as much as the head can handle before flow stalls)
750 Holley 4 corner idle
Port match intake to heads
4 (or 5) speed transmission
Multi sparking ignition/Chrome box/FBO ignition box
Open plug gap to .050-.055 or until it misses
 
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