• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

'67 GTX Engine Setup Cam Combo

Zancat

Well-Known Member
Local time
10:23 AM
Joined
Feb 9, 2013
Messages
86
Reaction score
18
Location
San Diego (North County)
Hi All,

So I'm not real happy with the way our car is working. Had an engine built by a local race motor guy and here is what's going on:

Problems, won't idle in gear after it gets warm, at lights, etc. hard to start when warm. Just all around bad manners.
Engine temps seem reasonable (stock gauge only), but on the high side, not excessive, in traffic, lots of lights, etc. have a Griffin radiator, with shroud, with flex fan (i know) due to fitment with March pulley kit. Looking at the Jag clutch or making an adapter for a fix blade. I put a carb insulator plate on it and it helped quite a bit. I really think I am having a fuel heat issue, and an aggressive cam is making it harder to deal with.

Car is a street car with 727, 2400 stall.
9.5:1 CR
Original HP 440 block, steel crank, stock rods, 040 over, forged pistons
906 heads, hyd lifters, 1.6 roller rockers
Schneider 2964 cam - 244°/244° @ .050, 112° sep, .560/.560 lift
Eddy 650 AFB style - regulated @ 4.5PSI
Eddy CH4B (which is cracked, and I have off the car now)
Mopar electronic ignition (orange box)
Stock exhaust manifolds, with new exhaust, X tube, flowmasters, 2.5" to mufflers, 2-1/4" back from there

Requirement - I want the stock air cleaner to fit.

The Cam seems way too big for this setup to me. I am considering putting a stock intake on it, and while I have it this far apart putting a milder cam in the engine. I am also considering blocking off the heat riser (we are in so cal). We just want this car to run good and have fun cruising. I want it real drive-able for my wife, after all, it's her car. :)

Thoughts? Am I on the right track? My experience lies in off road fabrication, I'm not much of a V8 guy. I understand the mechanics, but have limited experience.

Zancat
 
that cam will never work with stock exhaust manifolds. with those 1.6 rockers there's probably close to .600 lift at the valve. hope that was thought about when the heads were built. without big valve port work the heads are only good for about .450"-.500" lift. carbs too small. no quench.
 
that cam will never work with stock exhaust manifolds. with those 1.6 rockers there's probably close to .600 lift at the valve. hope that was thought about when the heads were built. without big valve port work the heads are only good for about .450"-.500" lift. carbs too small. no quench.

So you thinking a 750CFM w/ ~.480 purple stick style?
 
So you thinking a 750CFM w/ ~.480 purple stick style?

The carb is small for your setup but should work well enough to run around town as your wife's car. The 650 avs gives good gas mileage when setup right and is responsive but doesn't like under hood heat, at all. The carb spacer was a good call. try setting your idle speed higher in neutral so that your idle rpm in gear is around 800 or so. May have to set it to 1000-1200 in park.
 
Good advice so far.

In addition............

What is the initial ignition timing you are using? With that cam it should be close to 20 degrees initial with a 36-38 degree total.

If you change cams try to get something with 8-10 degrees and no less than 6 degrees more exhaust duration than the intake. Certainly not the single pattern cam you have now. To keep from getting into detonation with your compression ratio and the no quench, large combustion chambers, I wouldn't use anything smaller than 230 degrees at .050" on the intake side.
 
Good advice so far.

In addition............

What is the initial ignition timing you are using? With that cam it should be close to 20 degrees initial with a 36-38 degree total.

If you change cams try to get something with 8-10 degrees and no less than 6 degrees more exhaust duration than the intake. Certainly not the single pattern cam you have now. To keep from getting into detonation with your compression ratio and the no quench, large combustion chambers, I wouldn't use anything smaller than 230 degrees at .050" on the intake side.

Pretty sure timing is 20 initial, and 34-36 total now

Looking at this cam:

Cam Style: Hydraulic flat tappet

Basic Operating RPM Range: Idle-5,800

Duration at 050 inch Lift: 228 int./241 exh.

Advertised Duration: 268 int./284 exh.

Valve Lift with Factory Rocker Arm Ratio: 0.450 int./0.458 exh. (with my 1.6 rockers this would be .480 / .489)

Lobe Separation (degrees): 115

Zancat
 
That cam on a 115 LSA is a factory HP cam. Good choice for a driver. Not sure how it will do with the 1.6 rockers but since you have them you may as well find out.

Your original cam is pretty crazy for the above described combo and it really needs to come out. 9.5:1 CR will be good for pump gas too
 
Follow up

So I just drove the car with the 115° LSA cam, very happy. It was worth the effort to get that other cam outa there. Smooth idle, works great with the 727. Torque is better, get a real nice 2nd gear scratch with 3:23's. :) Great manners. Wife will be able to drive and enjoy her car now.

Thanks for the help folks,

Zancat
 
Hi All,

So I'm not real happy with the way our car is working. Had an engine built by a local race motor guy and here is what's going on:

Problems, won't idle in gear after it gets warm, at lights, etc. hard to start when warm. Just all around bad manners.
Engine temps seem reasonable (stock gauge only), but on the high side, not excessive, in traffic, lots of lights, etc. have a Griffin radiator, with shroud, with flex fan (i know) due to fitment with March pulley kit. Looking at the Jag clutch or making an adapter for a fix blade. I put a carb insulator plate on it and it helped quite a bit. I really think I am having a fuel heat issue, and an aggressive cam is making it harder to deal with.

Car is a street car with 727, 2400 stall.
9.5:1 CR
Original HP 440 block, steel crank, stock rods, 040 over, forged pistons
906 heads, hyd lifters, 1.6 roller rockers
Schneider 2964 cam - 244°/244° @ .050, 112° sep, .560/.560 lift
Eddy 650 AFB style - regulated @ 4.5PSI
Eddy CH4B (which is cracked, and I have off the car now)
Mopar electronic ignition (orange box)
Stock exhaust manifolds, with new exhaust, X tube, flowmasters, 2.5" to mufflers, 2-1/4" back from there

Requirement - I want the stock air cleaner to fit.

The Cam seems way too big for this setup to me. I am considering putting a stock intake on it, and while I have it this far apart putting a milder cam in the engine. I am also considering blocking off the heat riser (we are in so cal). We just want this car to run good and have fun cruising. I want it real drive-able for my wife, after all, it's her car. :)

Thoughts? Am I on the right track? My experience lies in off road fabrication, I'm not much of a V8 guy. I understand the mechanics, but have limited experience.

Zancat


Im sure the wide centerline 'seemed' good when the thought of stock manifolds would be used.
The exhaust pipes are too small , carb is small, didn't need 1.6 from the sound of it... and doesn't make sense along with the small stock exhaust/manifolds. You can weld up that aluminum intake as a fix...but an rpm would be better.
Should have had me build it, but as far as i know we don't know each other...

BUT,,,,, 'IF' you went into that build half in and half out....it's kinda your fault.
You need to trust your builder, after finding the right one, and not second guess or chince out.
I have no idea how it actually worked out...but reading the combo screams to me that something forked the direction of the build.

- - - Updated - - -

So I just drove the car with the 115° LSA cam, very happy. It was worth the effort to get that other cam outa there. Smooth idle, works great with the 727. Torque is better, get a real nice 2nd gear scratch with 3:23's. :) Great manners. Wife will be able to drive and enjoy her car now.

Thanks for the help folks,

Zancat

Like i was saying in the first response i had and it's proved in this quote above...3.23 gears!!! not the right gear for what you had, even the cam you have now the 650 carb is small.
 
Auto Transport Service
Back
Top