To Much Cam?

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72plymouthscamp

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My combo is a 318 .040 over kb167 zero deck mildly ported 302 heads milled .025 the chambers are cc'ing at 58 purple .508 292adv. 108CL cam wieand stealth intake holley 670 carb mech. fuel pump 3000 stall converter 727tf 8 1/4 rear 2.94 sg. Im being told its to much cam and im starting to agree, so I was thinking of a lunati 268 cam. Thoughts anyone????
 
Try the timing I suggested first, it's basically free and make a bigger bushing.

A 268H is a decent cam.
 
From the onset is does sound like to much for the small cube engine. Cool sounding cams quickly become a pain in the A$$ after you drive a while.
 
I built a 70 340 4sd Duster many years ago and I used the 484/284 Purple cam installed at 104 and though it sounded great it was not so much fun after driving it for a while.
 
Not the best cam for a daily driver, but that combo would work much better with a set of 4.10 gears :-D
 
Well its not a daily driver more like sat. nite get in trouble type thing for me maybe drive it to work once in a while.
 
Yes its a bit much.But a 268 cam would be better and that wont be enough stall with that 292 cam also.
 
Well I went with what the guy at the trans shop suggested and he is diehard mopar guy has a real nice 7.5 sec lebaron.
 
I almost spit out my coffee when i seen this :sad3:
You build a perfect combination and then want to change the cam???
Your running no gear in your car with a 292 adv.duration cam and think maby it has too much cam.#-o
When you put gear in your car your going to think that you put a new motor in and it's a big block.
You sound like you want to have a fast car and thats what you have but you took the heart out of it with 2.94's.
What size tire you running???????
I would not run any less gear then 4.30's
Let's put it this way:
Thats like building a stroker small block and putting 273 iron manifolds on the motor and then saying i sould have build a smaller motor because it run's like a bag of rocks.
You sould video tape the car the way it takes off now and the way it is after the gear change.
YOUR ALL SET \\\\\\\\\\\\\\\\\\\ GEARS AND SLICKS CAUSE YOUR GONNA NEED EM :laughing:
 
Hey t67 I have a 26 in tall tire and its about 9 in wide and i know the gearing is an issue among other things like timing
 
You might try the gear in it first before you change out the cam. It`ll probably drive like a different car with the higher gear.
 
What company made your convertor???
Sounds like it's a little tight.(lower stall then it sould be)
The carbs pump shots are too lean or too rich.
If the car falls on it's face it's too rich.
If the car stutters and then die's it's to lean.
What size pump nozzles do you have front\rear
and whats your total timing at?
It's not making the power it sould, so the stall speed on the convertor won't be what it sould also.
If you never changed the power valve then thats part of the problem too.
try this:
Put in a 3.5 power valve
front pump shot 35
rear pump shot 40
red cams for pumps
69 front jet
78 rear jet
36 total timing
four hole spacer \\ one inch if you have hood clearance 1/2 inch if you do not
3924 autolite plug or a plug of the same heat range
LET ME KNOW WHAT YOU HAVE NOW FOR ALL THESE.
WITH NO GEAR IT WILL BE VERY TEMPERAMENTAL.
 
Its just a stock holley 670 street avenger carb I did change out the jets but cannot remeber to what. I mean at idle when you give it some foot its real snappy rpms jump up nice, when its in gear is when the problem starts. NO BALLS
 
Whats the size of the power valve
and whats your total timing??
 
The power valve is whatever it came with not sure, the timing is unknow at this point. I thought it was around 34* but im thinking its way more than that. I have been talking to crackedback in private and he is really opening my eyes to the timing issue I am having. I will keep posting my progress as the days go by. Im sining off for the night now.....
 
It's all in your carb and timing as with any tune.
This is true if all else is good \\ correct plugs for your compresion \\ a good ignition system ie:wires\cap\rotor ect...
How does your car run on the highway above 3000 rpm's????
 
Stock 670 Holley's had a 6.5 pv so I'm sure that needs dropped down to at least a 4.5 but you need to run a vacuum check in gear to determine what it needs. It should be about 2 inches lower than idle vacuum in gear. As stated earlier a real big problem is gears too. Since the converter is rated at 3k and is only stalling 2300 that tells me your engine isn't making much low end torque. Remember the higher the torque output the higher the stall will be. So even if you put lower gears in it it probably won't stall any more. Did you degree in the cam when you installed it? What is the timing curve? i.e. how much initial and total timing are you running and when is the total all in by? With a cam that big you need a lot of initial timing with the total all in by 2500-2700. If not it won't have any guts down low.

Sorry to be repetitive about the timing. I didn't notice the post where you said you had talked to Rob about it until after I posted this.
 
I have a xe274 im trying to sell used no more then 200miles lobes are all great if you decide to get another cam
 
I think that you should keep the purple shaft. Here's why; youve got KB 167 pistons set at 0 deck. most likely a .040 gasket and 58cc chambers in the 302 castings. When you calculate it out it comes out to over 10.25:1 compression. the "dynamic" pressure might be too much if you go to the smaller cam. (cranking pressure) Do you want to use pump gas? Race gas?
The bigger cam will bleed off some pressure and help out the 302 castings which need to be ported as much as possible. Although with the swirl design you can get away with a little extra compression. A good street engine can get away with about 7.5:1 or maybe 8:1 of DYNAMIC compression. I believe you would be over 8:1 on the dynamic with the 268 cam. (I believe the intake closes at 60 degrees ABDC with the 268 cam)THis is all calculated by the closing point of the intake valve (plus other things) in relationship to the piston after it comes to the bottom of the intake stroke /starting into the comp. stroke. (I think 160 to maybe 170 wpuld be a safe limit of cranking pressure on a gauge). Get a compression gauge and see how much cranking pressure you have.
I look at it this way; big cams need compression and high compression needs a bigger cam. Lower compression needs a small cam.
Ideal situation if you wanted to use the smaller cam would be J heads (70 cc). The mopar factory high stall convertor stalls at about 1800~. A very mild B&M convertor would work with your setup, maybe a 2800 and yes some good gears. 3.91 would be ok in a light car.
This is all just my opinion. Getting the "combo" right is the most important thing. You must look at all variables and everything must work together.
 
OK acually it is a 318 .040 over compressed gasket thickness is .028 gasket bore is 4.060, zero deck 5cc valve relief on the piston, 58cc head chamber, intake side of the head is gasket matched ( as much as I could ) exhaust side is gasket matched and some bowl work done there aswell. I think its more of a timing/gear isue now just from hearing what the majority is saying. I know its low dynamic compression until the rpms come up. Obviously because the cam dosnt start making power until 2800 rpm and like I said in a previous post it sucks from go but if your rollin at 30 and give all the foot you can she goes. I will try all of suggestions I have been given, after all this is a tech support site in a sense thank you to all..............
 
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