351C Engine Strategy Consult

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72Q-code

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Location
Columbus Ohio
My Car
72 Q-code Mach 1, 351C 4 speed.

72 F Mach 1, 302 Automatic W/air.
OK,

Here comes another “what to do with the engine” thread, be forewarned:)

The engine came out of my car and went on the stand in late 2002. When I removed it the engine was running healthy, happy, other than some leaking valve stem seals. According to the previous owner it was rebuilt in the early 90’s (I have owned it since 95) and it has less than 10,000 miles on that rebuild. I planned this to be a winter freshen up the engine bay, then go right back in spring of 2003. Fast forward to now, eight years later, and thanks to rust findings and having kids the engine is still on the stand.

The engine compartment itself is now ready, and I am turning attention to the engine. I power-washed the engine this weekend. Now I need to decide what to do next. Originally I planned on cleaning the block and heads with a wire wheel and painting them, and removing the covers, pan, and intake to media blast and do the same. Install new valve stem seals, reassemble, and drive.

Now I am beginning to wonder if that is my best option. As long as the engine has been idle, and since it is out already, should I dig in deeper? It has been sitting but in a climate controlled garage, should I worry about rust on the crank/cam/other places? I am not sure if I have one piece stainless exhaust valves, but I have read enough to know that if I do not I probably should. Should I go ahead and plan on disassembling the whole engine, have the block and heads hot tanked and checked at a machine shop and then reassemble? Perhaps I need to get the pan and intake off first to evaluate further…

My goals for this engine are a reliable street weekend cruiser with no need for big horsepower gains. It would be nice to keep the costs to a minimum, but if I should spend a little money now to save a bunch later I will. I can do the disassembly and reassembly myself (with a little help from my friends here if needed:). I also would really like to get this car back on the road soon. Early this summer would be ideal, it has just been WAYY too long.

To further complicate my decisions, I also have a nice set of (supposedly) rebuilt two barrel heads and an Edelbrock aluminum dual plane intake like this:

http://www.hawkinsspeedshop.com/year-end-blowout-sale/edelbrock-performer-intake-manifolds-intake-manifold-performer-dual-plane-aluminum-natural-square-bo.html

My original plans were to reinstall the last known running configuration of 4V heads and stock cast iron intake then swap to the other stuff later to see what net gains I saw. Now, am I better off just building it that way from the start? I have 3:50 gears (recently verified after thinking they were 3:91’s) and a 4 speed FWIW.

Right after removal circa 9/2002:

first_out.JPG

As it has sat on the stand since then:

eng.JPG

Thoughts?

~Jim

 
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If you are worried about it, I would just take the oil pan and the heads off and take a look at what your working with. The one piece valves are a very good idea, you can tell if you have one piece valves by looking at the valve keepers, originals have multiple grooves, one piece valves have a single groove usually. But then again, it doesn't sound like you plan on much high rpm action so the valves would probably be fine. My engine actually still has the original valves in it, despite constant abuse they have held up fine.

The 2v heads would more than likely make it produce less power, unless they are the high compression Aussie heads.

What I personally would do, is pop the oil pan off, inspect everything, clean up the engine, replace any seals and gaskets that need to be changed, then go from there adding some basic performance upgrades, edelbrock intake, carb, msd ignition etc.

 
I assume the engine turns freely with the plugs out and no water entered the engine when it was washed. If you have access to a leak down checker do a leak down check before any disassembly. This will tell you the general state of ring sealing and valve sealing. Sell the 2V heads and intake. The 2V builds more torque issue is way over played by those with heavy cars, 2.78 gears, and using parts that are not well matched to each other. You have a 3.50 gear which should work well. The valve issue is not about steel or stainless steel (although today many replacement valves are SS). It is the design of the valve keepers, single groove or three groove. The 3 groove design has too much slop, weakens the tip, and causes failure. Since it is out of the car, and you plan to buy new valves, I would at least pull the pan, intake, and heads and check everything rods, mains, cam, pump, and timing chain set. IF the cam is stock Ford 1972 CJ consider advancing the cam 4 degrees. The factory retarded the cam 4 degrees trying to meet emissions standards. This made the engine sluggish at lower RPMs. If you find significant scarring on the oil pump gears replace the pump with a standard volume pump. Never use a high volume pump with a stock capacity oil pan. It pumps too much oil into the valve covers and starves the rods and mains. IF you end up completely disassembling the engine, consider having oil restrictors installed to lessen the flow of oil to the lifters and consequently increasing the oil flow to the rods and mains (you can still use hydraulic lifters). The intake will support more power than you say you want, so use it, unless you want to change to a square bore carburetor (even then you could use and adaptor, but 70 and early 71 near square bore 4V intakes are cheap). If the 4300-D carb was working fine, use it with the stock intake and count yourself as being very lucky. If everything checks out OK you are only out the cost of the valves, a valve job, the gaskets and seals, and some time. And it bought you a lot of peace of mind. If it doesn't check out OK you saved yourself a lot of time, work, and brain damaging frustration by finding the problems now, before it is back in the car.

Good Luck,

Chuck

Forgot to say wipe down any surface to be painted with wax and grease remover, then again with a clean dry cloth. Then the paint will stick.

 
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If you are worried about it, I would just take the oil pan and the heads off and take a look at what your working with. The one piece valves are a very good idea, you can tell if you have one piece valves by looking at the valve keepers, originals have multiple grooves, one piece valves have a single groove usually. But then again, it doesn't sound like you plan on much high rpm action so the valves would probably be fine. My engine actually still has the original valves in it, despite constant abuse they have held up fine.

The 2v heads would more than likely make it produce less power, unless they are the high compression Aussie heads.

What I personally would do, is pop the oil pan off, inspect everything, clean up the engine, replace any seals and gaskets that need to be changed, then go from there adding some basic performance upgrades, edelbrock intake, carb, msd ignition etc.
+1 on the above

Add cam upgrade, straight up timing set and headers. Ditch the autolite carb.

 
Also I am pretty sure the Edelbrock intake can also be used on the 4 v heads. I have the Air gap and they only make it for 2v heads but when you read the description it says it can also be used on 4v heads. And my Air gap is on 4v closed chamber heads and it added 50hp to the dyno run.

 
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when I got my 72 351 it had been sitting for several years. the guy would start it, he said every month. well when I pulled apart I found the rod and main bearings very pitted and pealing.... did not look right to me. I took them to my mechanist and he told me it was from sitting so long to oil turns acidic. so with telling you my story, I would pull your bearing it may be worth you time. good luck!!

 
Also I am pretty sure the Edelbrock intake can also be used on the 4 v heads. I have the Air gap and they only make it for 2v heads but when you read the description it says it can also be used on 4v heads. And my Air gap is on 4v closed chamber heads and it added 50hp to the dyno run.
Yes I believe 2v intakes will fit on both style heads. The Air Gap intake is designed to work with their aluminum cylinder heads, which have 2v sized ports. The Air Gap intake is a real good intake though for both heads I would imagine.

The 4v edelbrock performer intake (not air gap) has ports/runners more suited to the ports on the regular 4v head.

Now the question is, on a 4v headed engine, would the regular Performer 4v intake or the 2v Air Gap intake make better power?

I'm betting on the Air Gap.



 
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All advice above is excellent. I can add nothing except that if you do nothing your engine is probably fine as it currently sits...but while it is out it is fine to tweak in the areas as mentioned above if you feel so inclined -or not. Either way no big deal.

 
Also I am pretty sure the Edelbrock intake can also be used on the 4 v heads. I have the Air gap and they only make it for 2v heads but when you read the description it says it can also be used on 4v heads. And my Air gap is on 4v closed chamber heads and it added 50hp to the dyno run.
Yes I believe 2v intakes will fit on both style heads. The Air Gap intake is designed to work with their aluminum cylinder heads, which have 2v sized ports. The Air Gap intake is a real good intake though for both heads I would imagine.

The 4v edelbrock performer intake (not air gap) has ports/runners more suited to the ports on the regular 4v head.

Now the question is, on a 4v headed engine, would the regular Performer 4v intake or the 2v Air Gap intake make better power?

I'm betting on the Air Gap.
I think you get more low end torque with the 2v air gap. As far as hp goes I am not sure. But as I said above I got a 50hp increase from stock closed chamber to Air gap. I have an article that I scanned from the engine masters mag that tests intakes I'll see if I can post it and if it's readable.

 
All,

Thanks for the advice so far. Regarding the leak down tester, I do not have one, but I will soon. I have a compression tester but never owned a leak down tester. After reading up about them, one needs to be in my arsenal. I actually have parts to build a good one thanks to my rather well stocked pneumatics bin thanks to my job...but that is another post. Here is a pretty decent page about building and using a leak down tester:

http://www.motorcycleproject.com/motorcycle/text/Leakdown.html

So the plan is to:

1) Pull the pan and look at a couple mains and ensure there is no rust or pitting.

2) Ensure the motor rotates freely with the plugs out.

3) Reinstall plugs and pan and do a leak down test.

...and go from there. I guess since the motor will be cold my leakage may be a bit higher, but I want to see consistency, right?

Regarding the carb and cam. I have rebuilt the 4300D once and it has really run like a charm ever since. It starts on the first turn, and my plugs have always read pretty darn good. Considering myself lucky!

Cam. No clue. The car came with two cams in boxes that were used. I think one is the stock Ford cam. I have no idea what is in it. I figure with some dial indicators and V blocks which I have I can do a reverse engineering effort on the cam. I have to admit I have not done this before, so if anyone has or knows of a good how to on this I am all ears.

The car does have an MSD Unilite distributor in it, which is nice. The coveted replacement dual points for the stock distributor that I paid through the nose for dropped a rub block less than 100 miles after I installed them. It took me half a day to set them up and balance them perfectly when I installed them. It took less than hour to drop in the Unilite and the car ran better immediately.

I like the stick with the 4v, cast intake and 4300D plan for now. The car ran plenty strong when I parked it. If I do decide to sell the intake and heads that is money I can dump right back into the car "guilt free". Also the cast iron exhaust manifolds will likely stay. I went down the header route on the 302, and the cast irons are back now on that car. I guess I am getting old…but the noise and leakage problems I had outweighed the HP gain for my needs.

Thanks, please keep the advice flowing.

~Jim

 
All,

Thanks for the advice so far. Regarding the leak down tester, I do not have one, but I will soon. I have a compression tester but never owned a leak down tester. After reading up about them, one needs to be in my arsenal. I actually have parts to build a good one thanks to my rather well stocked pneumatics bin thanks to my job...but that is another post. Here is a pretty decent page about building and using a leak down tester:

http://www.motorcycleproject.com/motorcycle/text/Leakdown.html

So the plan is to:

1) Pull the pan and look at a couple mains and ensure there is no rust or pitting.

2) Ensure the motor rotates freely with the plugs out.

3) Reinstall plugs and pan and do a leak down test.

...and go from there. I guess since the motor will be cold my leakage may be a bit higher, but I want to see consistency, right?

Regarding the carb and cam. I have rebuilt the 4300D once and it has really run like a charm ever since. It starts on the first turn, and my plugs have always read pretty darn good. Considering myself lucky!

Cam. No clue. The car came with two cams in boxes that were used. I think one is the stock Ford cam. I have no idea what is in it. I figure with some dial indicators and V blocks which I have I can do a reverse engineering effort on the cam. I have to admit I have not done this before, so if anyone has or knows of a good how to on this I am all ears.

The car does have an MSD Unilite distributor in it, which is nice. The coveted replacement dual points for the stock distributor that I paid through the nose for dropped a rub block less than 100 miles after I installed them. It took me half a day to set them up and balance them perfectly when I installed them. It took less than hour to drop in the Unilite and the car ran better immediately.

I like the stick with the 4v, cast intake and 4300D plan for now. The car ran plenty strong when I parked it. If I do decide to sell the intake and heads that is money I can dump right back into the car "guilt free". Also the cast iron exhaust manifolds will likely stay. I went down the header route on the 302, and the cast irons are back now on that car. I guess I am getting old…but the noise and leakage problems I had outweighed the HP gain for my needs.

Thanks, please keep the advice flowing.

~Jim

It sounds like you have a plan. Let me know if I can help.

Chuck

 
My advice is dont downgrade to 2V heads and that intake, you will lose power and resale value on your car. Remove intake and oilpan for inspections, and new gaskets/oil seals since they are probably old anyways.

If you see anything inside the lifter valley or crankcase like sludge or metal then its rebuild time if its all clean and shiny you may be ok to run

 
Again thanks.

I have 100% decided to stay with the 4V stuff. Other stuff will likely be sold. I recently realized my attic is better stocked than some speed shops, it's time to thin it out a bit! I hope to pull the pan and do some inspecting tonight. I'll post some pics if I do.

~Jim

 
The attic speed shop got my attention. What all do you have? There may be something I just gotta buy!

Chuck

 
The attic speed shop got my attention. What all do you have? There may be something I just gotta buy!

Chuck
For now a set of open chamber 2V heads, and a new Edelbrock 2V performer aluminum dual plane intake is all that I really want to part with.

I also have a set of 289 hipo heads with the Buddy Bar Shelby intake and valve covers, a pair of 427's, a low mileage 390 out of a 68 Torino...and on and on. Most of this stuff was in my dad's collection and my brother and I now own and will keep. Seeing all of the projects yet to be started, I am now aware that the 2V Cleveland stuff is just never going to see use by me, and should be put into the hands of someone that will.


OK, got the bottom end checked out, and I like what I see I think. the 4 bolt main caps were a pleasant discovery. I figured they should be there, but did not know for sure. I took some hopefully helpful pics. To me, this looks really clean. I puled the plugs and it rotates pretty easily with a ratchet. The bearings look to be not fully seated in yet? (I only pulled main cap #3) and the crank looks smooth.

Timing chain is double and metal gear. No sludge or metal to be found. I did not get to dig into the heads to check the vales. I want to do a leak down test first. So what do you guys think?

Just after pulling the pan for the first time on this engine. Yeay, 4 bolt mains!

engine_disassemble 004.jpg

Closer look at main caps:

engine_disassemble 005.jpg

Timing chain:

engine_disassemble 008.jpg

Bearing:

engine_disassemble 010.jpg

I have a bunch more pics that I put in an album on Flickr here:







~Jim

 
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It looks pretty good. Do you know what the dark colored "stuff" on the oil pan baffle is?

Chuck

 
It was a layer of *thick* oil (I cannot bring myslef to say sludge). It wiped off with a rag and did not have a gritty or metallic feel to it.

I drained the oil when I yanked the engine, and I think that was what collected on the flat of the baffle and sat there for the past 8 years.

I am surprised by the baffling and windage in the pan. I had figured on bead plasting the outside to paint it, but I have to admit I am now concerned with getting all of the abrasives out of the baffling if I do...

 
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