My 383's crappy dyno results...

[rfoll]

The Lunati cam is in the car because it came in the 383. The engine was someone else's eBay purchase that was never installed. It turned out to be as much of a nightmare as the 350 that came in the car. The "Scat rods" in the 383 turned out to be from a 305. Trying to get the engine in the car for the summer meant some aspects of the engine build had to be compromised. Trying to keep this from spiraling out of control meant a new cam wasn't in the cards.

[77cruiser]

My biggest gripe from camshaft manufacturers is when they include an "rpm range" for a specific cam....like they know which heads are on the engine, exactly how many cubes it is, what the flow numbers are, etc. They need to leave that line off the description.

I love it when they do it. It makes it easier for me to sell my cams.

Nothing makes my competition look dumber, then a catalog listing cams for 262" to 400" SB chevys, and stating the RPM band would be the same.

Looking at one right now.
SB Chevy, 262-400
4,200-8,200 RPM
Good all around mid-range power
263/273 @.050"
.640"/645" Lift
112 LSA

In a 400", that cam would be done by 7,600
In a 283", that cam wouldn't start running until 6,000rpm.

Or if it has 180cc port heads or 235cc port heads.

[Walter R. Malik]

[quote="rfoll"]The Lunati cam is in the car because it came in the 383. The engine was someone else's eBay purchase that was never installed. It turned out to be as much of a nightmare as the 350 that came in the car. The "Scat rods" in the 383 turned out to be from a 305. Trying to get the engine in the car for the summer meant some aspects of the engine build had to be compromised. Trying to keep this from spiraling out of control meant a new cam wasn't in the cards.[/quot].

THEN ... if the owner wasn't willing to buy those needed parts to make it a viable combination, you or him should have no complaints what-so-ever about the way it runs.

He got exactly what he paid for.

[67RS502]

My 383 with a 224/224 cam ran 10.70s in my Camaro, not that its the right cam. I'm just showing you how far off your cam is.
Then you have a vacuum sec. carb, meaning the secondaries wont be open until high rpm.
We've all seen cars with 1" airfilters or junk exhaust and owner wonder why it doesn't run.
You need to get some tires and take it to the track. Tune it, and find all the things holding the engine/performance back.
Most of the time its induction, exhaust, fuel systems and traction. You could stick a 500hp engine in a car that has issues and that engine looses 100-150hp from the dyno to the car.
In reality track performance is what matters, unless you just want to brag about dyno #s.

[rfoll]

The Lunati cam is in the car because it came in the 383. The engine was someone else's eBay purchase that was never installed. It turned out to be as much of a nightmare as the 350 that came in the car. The "Scat rods" in the 383 turned out to be from a 305. Trying to get the engine in the car for the summer meant some aspects of the engine build had to be compromised. Trying to keep this from spiraling out of control meant a new cam wasn't in the cards.[/quot].

THEN ... if the owner wasn't willing to buy those needed parts to make it a viable combination, you or him should have no complaints what-so-ever about the way it runs.

He got exactly what he paid for.

The current issue is a desire for more low end torque. If I had known beforehand that he wanted a stump puller, I would have advised another cam and a lower compression ratio.

[cjperformance]

Yep cant agree more with the suggestions re manifold and convertor swap , OR, smaller cam , either will transform that car.
If opting for a smaller cam, Id even say go smaller cam AND sell the airgap and fit an EPS.

[Crews69]

Wow, well done; we need a plaque to award for the most complete driveline build specs EVER!

Haha thanks. I actually just copied and pasted my notepad page in which I keep and update most of my cars details.

[Crews69]

TMI. I'd run a 3500 to 4000 stall converter.

Isn't that a bit much for the street? All I wanna do is drive this to the beach on sunny days. I mean I want it faster than the modern minivan lol. But I want it driveable with good low end grunt. High rpm power isn't as important to me. I'll never really use it.

[Crews69]

What's with the squiggly lines on the dyno sheet?

Is it where the wheels were spinning on the rollers?

It's a bit worthless like that?

Yeah I was wondering the same thing... They had the car For two weeks. And ran it on the dyno multiple times. But I was only given this one sheet.

[Crews69]

With a street car ...one has to remember that Wide Open Throttle power has little to do with "drive around" part throttle power and response.
I suspect you are now feeling that phenomena first hand.
Yes! I am most certainly feeling that phenomena. It's choppy under about 2400 rpm. Soon as you get above that it runs great. seems like it just loves the higher rpms.
A 2,400 RPM stall torque converter is not high enough or the cam is to big; (they do not MATCH one another when using that size cylinder head).
I don't even really know how a stall converter is supposed to feel to be honest. It's not like I can just power brake it and it waits to get to that rpm until it engages right? I have noticed that when I ratchet shift down into second while driving. Then give it gas. It feels like neutral until exactly 2400 then engages.

EDIT: If it was mine I would choose to put a smaller, better suited cam in it.

Wouldn't changing the converter be easier? Or would a larger converter not be good for the street? My intake is glued down like a SOB lol. Cam change is gonna be a pain.

[Crews69]

Put a victor Jr on it, and it'll pick up a bunch of power above 5,500rpm.
If you want to stick with the Performer, drop the cam duration down to around 230, so the cam will match the manifold.

I would like to use this car on the street and highway only. No need for power up high I'll never really use it. Eventually I will build and install an LS based engine. And finish upgrading the chassis which will be geared towards a pro touring design. Not a drag car. So whatever I do to this 383 is really just wasted money. But it's gonna get me by for now. So I don't want to spend a grand on a roller cam. I need to find a good flat tappet hyd. Cam that will match the rest of my setup "heads, bottom end, tranny and converter" and give me more power than my wife's minivan But be good for the street and highway.

[MadBill]

... My intake is glued down like a SOB lol. Cam change is gonna be a pain.

If you don't mind reusing the same lifters, buy/build a bunch of cheap 'magnets on a stick' to hold them all up while you slide out the cam.

[David Vizard]

My biggest gripe from camshaft manufacturers is when they include an "rpm range" for a specific cam....like they know which heads are on the engine, exactly how many cubes it is, what the flow numbers are, etc. They need to leave that line off the description.

I love it when they do it. It makes it easier for me to sell my cams.

Nothing makes my competition look dumber, then a catalog listing cams for 262" to 400" SB chevys, and stating the RPM band would be the same.

Looking at one right now.
SB Chevy, 262-400
4,200-8,200 RPM
Good all around mid-range power
263/273 @.050"
.640"/645" Lift
112 LSA

In a 400", that cam would be done by 7,600
In a 283", that cam wouldn't start running until 6,000rpm.

Mikey,

With you 100% on this one. I don't know who most of the cam companies get to do their catalogs but I am sure it's not a cam expert. If I was a little more harsh on the speed industry I would have to say there is a great expose story here.
DV

[superpursuit]

... My intake is glued down like a SOB lol. Cam change is gonna be a pain.

If you don't mind reusing the same lifters, buy/build a bunch of cheap 'magnets on a stick' to hold them all up while you slide out the cam.

Madbill. Looks like you have mistaken his cam for a hydraulic roller. His cam is actually a flat tappet hydraulic. Re using these lifters on a new cam would be a disaster.

[Crews69]

... My intake is glued down like a SOB lol. Cam change is gonna be a pain.

If you don't mind reusing the same lifters, buy/build a bunch of cheap 'magnets on a stick' to hold them all up while you slide out the cam.

that is genius lol.
Would I need to change my pushrods or rocker arms? They are all brand new comp magnum roller 1.5's and new comp pushrods.