Tell me where I am going wrong.

Tell me where I am going wrong.

Joined: September 13th, 2007, 7:49 pm

February 10th, 2012, 7:54 pm #1

I need some help IDing where I need to make a change. here is what I have,
1973 Mach 1 full body car just as it came new,full interior etc...AC,PS,PDB,etc.....351 CJ, now running closed chamber 4V's stainless one peice valves,guide plates,Crane roller rockers,Comp valve springs,locks, etc...NO porting.
The cam is a Comp 270 Magnum hydrolic 270dur. 519 lift(?) I will have to dig up the spec sheet. Installed straight up.Double roller timing chain.I just bought a SFI harmonic balancer for the Cleveland, a Pioneer and my timing marks seem to be off. When I throw the timing light on it the light is firing way off of my pointer.The car will not run below about 20 degrees initial, so I am back to timing by feel.I have to mix my gas, premium 93 and 110 race.
The pistons are the old TRW forged flat tops .030, Federal rings file fit. stock rods, crank,balanced etc...
Intake is an Offy dual plane 360,Holley 770 Street avenger vacum secondary.(I am limited on the intake due to using a factory ram ait system,must keep)
Using a Mallory unilite vacum advance distributor, no CD box.
Hooker super comp headers.(headers open at the track)
C6 trans with the factory CJ converter.
4:22 gears,limited slip 9",running 28x9x15 slicks.Also running a set of Cal Tracs,no traction issues.
Now I am almost embarased to tell you the rest after reading what you guys are getting out of your cars and trucks. I am only running consistent 8.70s, with a best 1/8th mile of 8.67 in good cool air.My best 60' has and is about a 2.03, at 80mph. The car pulls good up to about 5,000 and just starts nosing over.It will pull to 6,000 but it feels like it is starving.I really think it is probably my cam is all wrong.The car sounds great on the street and has a real nice loppy idle,drivability and throttle respons is very good.
Any Ideas and or suggestions.
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Joined: December 16th, 2003, 1:59 am

February 10th, 2012, 8:06 pm #2

i can see gains to be had in the cam & intake dept's

there are other intakes that will work with your Ram Air, the Offy's aren't very highly regarded for more than mild street

and yeah the cam should be wound out about there. more cam may want a little more than the CJ converter though

th combo chase is on

there'll be phantoms, there'll be fires on the road... and the white man dancing
Last edited by tinman351 on February 11th, 2012, 6:59 am, edited 1 time in total.
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Joined: May 20th, 2005, 4:48 pm

February 10th, 2012, 8:07 pm #3

I need some help IDing where I need to make a change. here is what I have,
1973 Mach 1 full body car just as it came new,full interior etc...AC,PS,PDB,etc.....351 CJ, now running closed chamber 4V's stainless one peice valves,guide plates,Crane roller rockers,Comp valve springs,locks, etc...NO porting.
The cam is a Comp 270 Magnum hydrolic 270dur. 519 lift(?) I will have to dig up the spec sheet. Installed straight up.Double roller timing chain.I just bought a SFI harmonic balancer for the Cleveland, a Pioneer and my timing marks seem to be off. When I throw the timing light on it the light is firing way off of my pointer.The car will not run below about 20 degrees initial, so I am back to timing by feel.I have to mix my gas, premium 93 and 110 race.
The pistons are the old TRW forged flat tops .030, Federal rings file fit. stock rods, crank,balanced etc...
Intake is an Offy dual plane 360,Holley 770 Street avenger vacum secondary.(I am limited on the intake due to using a factory ram ait system,must keep)
Using a Mallory unilite vacum advance distributor, no CD box.
Hooker super comp headers.(headers open at the track)
C6 trans with the factory CJ converter.
4:22 gears,limited slip 9",running 28x9x15 slicks.Also running a set of Cal Tracs,no traction issues.
Now I am almost embarased to tell you the rest after reading what you guys are getting out of your cars and trucks. I am only running consistent 8.70s, with a best 1/8th mile of 8.67 in good cool air.My best 60' has and is about a 2.03, at 80mph. The car pulls good up to about 5,000 and just starts nosing over.It will pull to 6,000 but it feels like it is starving.I really think it is probably my cam is all wrong.The car sounds great on the street and has a real nice loppy idle,drivability and throttle respons is very good.
Any Ideas and or suggestions.
1. Make sure the timing marks on the balancer are right. It's possible that you got a Windsor balancer and the timing marks won't be correct. Do you know how to check true TDC with a piston stop? I would start here first, as timing by ear can really hurt an engine. I built a 428FE for a guy. His buddy "timed it by ear" and it turned out that it had about 60 degrees of total mechanical advance in it...not good.

2. Just a shot in the dark....but when you put the timing light on the plug wire, are you sure it's #1 cylinder? I've seen some guys put the lead on the wrong wire by accident and then see that the marks/timing are off.

3. What are you calling straight up? Did you just install the timing chain dot to dot? If so, that's not straight up, it's just installing the chain dot to dot. Straight up means that the LSA is equal to the ICL. So even if you installed it dot to dot on the timing set, the cam could still have 4° advance built into it...

4. A 270H hydraulic cam isn't going to be a barn burner, but it should pull to around 5500 or so. How are your valve springs? Were they replaced with the cam? Do you think that it's a possibility they are getting weak?

I'm not sure where you are or what altitude you're at, so I'm just basically going off of the symptoms that you described: timing is off, and engine is nosing over at 5000. One big thing you mentioned is that it won't run under 20 degrees initial, so I would make sure that the timing light lead is on the front plug wire on the passenger side first. If that's good, then I would get a piston stop, some masking tape, and a sharpee, and find true TDC...

Brent Lykins
B2 Motorsports, LLC






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Joined: September 13th, 2007, 7:49 pm

February 10th, 2012, 8:18 pm #4

Bret you are right about the straight up comment, dot to dot on the timing.I am using the #1 plug wire as you say. I to feel that I may have receveived a Windsor balancer in a Cleveland box. I need to verify top dead center. I was told how to do it using a stop many years ago but have since forgoton.
I am in East Texas so I usually have good air.
You are right about the max RPM being 5500.
The springs are the correct match for the cam.The engine has about 6,000 mile on it.
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Joined: January 10th, 2002, 5:53 pm

February 10th, 2012, 8:23 pm #5

I need some help IDing where I need to make a change. here is what I have,
1973 Mach 1 full body car just as it came new,full interior etc...AC,PS,PDB,etc.....351 CJ, now running closed chamber 4V's stainless one peice valves,guide plates,Crane roller rockers,Comp valve springs,locks, etc...NO porting.
The cam is a Comp 270 Magnum hydrolic 270dur. 519 lift(?) I will have to dig up the spec sheet. Installed straight up.Double roller timing chain.I just bought a SFI harmonic balancer for the Cleveland, a Pioneer and my timing marks seem to be off. When I throw the timing light on it the light is firing way off of my pointer.The car will not run below about 20 degrees initial, so I am back to timing by feel.I have to mix my gas, premium 93 and 110 race.
The pistons are the old TRW forged flat tops .030, Federal rings file fit. stock rods, crank,balanced etc...
Intake is an Offy dual plane 360,Holley 770 Street avenger vacum secondary.(I am limited on the intake due to using a factory ram ait system,must keep)
Using a Mallory unilite vacum advance distributor, no CD box.
Hooker super comp headers.(headers open at the track)
C6 trans with the factory CJ converter.
4:22 gears,limited slip 9",running 28x9x15 slicks.Also running a set of Cal Tracs,no traction issues.
Now I am almost embarased to tell you the rest after reading what you guys are getting out of your cars and trucks. I am only running consistent 8.70s, with a best 1/8th mile of 8.67 in good cool air.My best 60' has and is about a 2.03, at 80mph. The car pulls good up to about 5,000 and just starts nosing over.It will pull to 6,000 but it feels like it is starving.I really think it is probably my cam is all wrong.The car sounds great on the street and has a real nice loppy idle,drivability and throttle respons is very good.
Any Ideas and or suggestions.
If you have to run 20 lead with closed heads, something is out of whack with the cam timing, etc or your balancer marks are not dialed in. Also, you should not have to mix 93 and 110 IMHO. You didn't state your compression, if you had it apart you should have those figures (deck clearance, chamber size, etc).

Dot for Dot on a 351C - there is a good chance it is off. I have yet to put a cam in a 351C without having to use a 9 way FRPP timing chain to get it dialed in. And once you locate TDC, you have to mount and check the timing marks - almost always they will be off some.

http://www.atlanticspeed.com/productcar ... tegory=298
The cam is fairly small for the application. Something more like this, with a better converter:
http://www.atlanticspeed.com/productcar ... tegory=298

Your car weighs a ton, comparatively. 80 mph is about 280 RWHP in a 3600 lb car.

A factory converter is at least 1000 rpm too tight for any performance combo IMHO.

If you are running the stock fuel system from the tank, the tank outlet may well limit your fuel delivery. The smaller Ford tank pickups will run a 351C out of fuel around 5200. Been there, fixed that.

>I am in East Texas so I usually have good air.
Unless the humidity is through the roof LOL!

1967 Falcon 4 door 351C-4V
1970 Mustang 351C-2V
http://raceabilene.com/kelly/hotrod
Owner built, owner abused.
Last edited by Falcon67 on February 10th, 2012, 8:27 pm, edited 1 time in total.
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Joined: May 20th, 2005, 4:48 pm

February 10th, 2012, 8:27 pm #6

Bret you are right about the straight up comment, dot to dot on the timing.I am using the #1 plug wire as you say. I to feel that I may have receveived a Windsor balancer in a Cleveland box. I need to verify top dead center. I was told how to do it using a stop many years ago but have since forgoton.
I am in East Texas so I usually have good air.
You are right about the max RPM being 5500.
The springs are the correct match for the cam.The engine has about 6,000 mile on it.
If you have a piston stop that goes in the spark plug hole, it's easy to check it.

Pull all the plugs out of the engine so that it's easy to turn over by hand.

Put your piston stop in the #1 plug hole.

Wrap a piece of masking tape around your harmonic balancer.

Turn the engine over slowly by hand in the normal direction until the piston hits the stop. Make a mark on the masking tape where the timing pointer points at that instant.

Turn the engine over slowly in the other direction until the piston hits the stop. Again, make a mark on the masking tape where the pointer points.

TDC should be exactly half way between those two marks that you made....which should be 0 on your balancer.

Brent Lykins
B2 Motorsports, LLC






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Joined: February 13th, 2006, 4:59 am

February 10th, 2012, 10:34 pm #7

I've seen some of the distributors that have not be recurved you had to run initial timing way up only to get to high up top( causing the nose over). Has yours been curved? If so it definatly sounds like cam timing.
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Joined: May 20th, 2005, 4:48 pm

February 10th, 2012, 10:39 pm #8

....It's certainly best to know where the cam timing is set, but a lot of guys shy away from advanced cam timing because they want the engines to pull harder up top. Sometimes it works like that, sometimes it doesn't, and I've seen a lot of races won with engines running a 98° ICL with a 108° LSA, turning 8800 at the trap.

There's a generalization that says that advanced cam timing absolutely makes the engine a dog up high, when it's usually lack of head flow, cam specs jacked up, no spring pressure, timing off, etc.

Brent Lykins
B2 Motorsports, LLC






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Joined: September 13th, 2007, 7:49 pm

February 10th, 2012, 10:49 pm #9

If you have to run 20 lead with closed heads, something is out of whack with the cam timing, etc or your balancer marks are not dialed in. Also, you should not have to mix 93 and 110 IMHO. You didn't state your compression, if you had it apart you should have those figures (deck clearance, chamber size, etc).

Dot for Dot on a 351C - there is a good chance it is off. I have yet to put a cam in a 351C without having to use a 9 way FRPP timing chain to get it dialed in. And once you locate TDC, you have to mount and check the timing marks - almost always they will be off some.

http://www.atlanticspeed.com/productcar ... tegory=298
The cam is fairly small for the application. Something more like this, with a better converter:
http://www.atlanticspeed.com/productcar ... tegory=298

Your car weighs a ton, comparatively. 80 mph is about 280 RWHP in a 3600 lb car.

A factory converter is at least 1000 rpm too tight for any performance combo IMHO.

If you are running the stock fuel system from the tank, the tank outlet may well limit your fuel delivery. The smaller Ford tank pickups will run a 351C out of fuel around 5200. Been there, fixed that.

>I am in East Texas so I usually have good air.
Unless the humidity is through the roof LOL!

1967 Falcon 4 door 351C-4V
1970 Mustang 351C-2V
http://raceabilene.com/kelly/hotrod
Owner built, owner abused.
Thanks Bret for the info on the way to verify TDC. When you started to desribe how it came back to me.

My fuel outlet on the tank is the factory 3/8 pickup, with no sock( use a good filter). I have a Holley Blue pump at the tank, with a Holley mechanical up front.

I do realize that I need another converter also. I am wanting to convert to a 4R70W for the overdrive and the close ratio gear set.That should be worth a bit better 60' and maybe a couple of 10th's. That is when I plan to get a better convertor.

I am at the point where I am going to pull the engine and pull it down for inspection, and maybe some more machine work etc...better attention to the details.I just through this one together in my garage, because I was not going to race it any more,yea right!I have been racing since 1970, never serious just for fun.Now that I am older I seem to be going more and more. I bought this car new thats is why I am stuck with such a heavy car and am restricted in some areas such as intake selection.

I am torn as to whether to invest in a roller cam or just stick with a flat tappet hydrolic / solid cam.

Should I look at more head work / porting?

I guess I should state my goals. I would really like to knock off a second of ET, some solid 7.50's and still be able to drive this car on a cruise night. I want to uphold the Clevelands honor,not gettin it done right now.

I know a strocker would be the ticket, but I just don't see it in my budget right know.
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Joined: May 20th, 2005, 4:48 pm

February 10th, 2012, 10:55 pm #10

...will put more of a damper on the bottom end performance as you'll need to spin the engine up a little higher to make the horsepower. The rearend gears that you have definitely put you in a better position though, since they will help with the engine being lazy on the bottom.

If it were me, I'd invest in some good port work (not necessarily making the ports bigger, but optimizing the shape and flow) and run a solid cam. Whether or not you go flat or roller will be based on the budget, but keep in mind that a solid roller will need a little more maintenance, more inspection intervals, and a change in valve springs, etc.

I spend more time helping guys try to ride the fence with their engine builds than anything else. Very few guys call in wanting an engine to go get groceries. Another small percentage want a full race motor. The majority of the guys want something in between. That's perfectly fine as long as you recognize you have to make compromises. You can't have an engine that idles like a factory car, gets excellent gas mileage, has gobs of power down low for cruising down now, but makes power at 7500 rpm...it's all a give or take.

Brent Lykins
B2 Motorsports, LLC






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