72 Q code cj engine rebuild

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chefabg123321

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My Car
1973 Q Code vert
previous post about my engine being filled with sludge. I have decided to go a head with a engine rebuild. I had many good suggestions from a lot of you but wanted to confirm what I'm doing going forward, as this is the first time I have done this.

5000 dollar budget

I'd like to keep this close to stock,but I like a little pep. This is a cruiser for the beach, not a race car. Questions:

1) i'm thinking about upgrading the cam, thought about using 71 cobra jet specs for a little extra. Any thoughts?

2) do I really need Hardened valve seats? I use premium gas.

3) maybe I should add a new intake? Of course I will keep the old stock intake in case I sell the car in the future. But maybe this is not necessary as I am not a racer.

4) definitely need a new carburetor, any suggestions. I currently have a Holly double pumper at 800 CFM.this came on the car when I bought it.

5)will upgrade to one piece valves. And match lifters and springs to cam

6) performance kit

http://www.summitracing.com/parts/fem-csmhp732-310/overview/make/ford

Will add valves and springs to this

7) add new roller rocker arms

8) resize rod ends

9) machine crank

Anything I missed?

 
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For the cam I would go through a cam catalog, like Comp Cams, and match a cam to your intended use, gearing, intake, and exhaust.

Yes, hardened valve seats are necessitated by the lack of lead in the gasoline, not grade of gasoline.

For your intended use, a new intake will likely only provide minimal improvements.

I believe 800 cfm is oversized for your build. I would consider fuel injection, the FiTech isn't that much more than the combined cost of a new carburetor and intake.

Yes on 1 piece valves.

I couldn't open the link.

Yes on 7 & 8.

9 depends on the crank condition.

 
Are you going to be putting the parts together or are you going to have the machine shop that does the work do it for you?

If you are going to assemble the parts then you should be able to come in under 5K.

Find a local machine shop that has been in business for awhile and has a good reputation and take them your parts - they will check for cracks, measure everything and tell you what you need and do not need for a minimal charge.

Heads will get hardened seats and new guides. Have the shop assemble them with your new springs and valves if your decide to get new valves. $1500.00 max for parts and labor.

The shop can recondition the rods with new ARP nuts/bolts, bore the block if needed, install new pistons on the rods and install new cam bearings in the block should be no more than $1000.00 in labor. You are not a racer so cast pistons and iron rings will serve your needs well and are cheap.

Keep the cam specs mild and toward low rpm performance - stock specs or close to stock.

Even very sludged up 351C engines often do not need to be bored over stock. The fact that your pistons popped out without a lot of pounding means there was not much of a ridge ring at the top. ie there was very little wear in the cylinders.

More important than single grove valves and keepers is replacing the rod bolts and nuts with ARP's.

It is an urban myth that the 2 piece valves will loose their heads "just because".

What happened was that Ford increased the strength of the rod bolts on the 351C 4V / Boss / and CJ engines but kept using the original rod nut. A nut that is prone to loosing its threads. So, the nut strips, the cap comes loose, the piston can now move up higher than normal and hits the valve. The valve stem bends and or snaps - lots of bad noises happen next. Valve gets the blame.

I have never had a 2 piece valve fail - even on full blown race engines. Nothing wrong with replacing them - they are cheap enough now a days so why not. (Just be sure to upgrade the rod bolts and nuts.)

So for around 2500 in machine shop cost and another 750.00 in parts you will have a complete long block less Carb/headers/distributor.

Headers are 300.00

Distributor - reuse your stock one and add a pertonix module - 100.00

Carb - 650 to 750 vac secondary holley - 450.00

another 300.00 for an intake.

You should be at $4400.00 ready to run.

Keep us posted!

- Paul of MO

 
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Are you going to be putting the parts together or are you going to have the machine shop that does the work do it for you?

I'm not able to do the work on this. Car is at my mechanics and he will drop off engine. This will add cost. I have done my homework on TEC here in West palm beach...they are a VERY highly recommend machine shop.
 
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Are you going to be putting the parts together or are you going to have the machine shop that does the work do it for you?

I'm not able to do the work on this. Car is at my mechanics and he will drop off engine. This will add cost. I have done my homework on TEC here in West palm beach...they are a VERY highly recommend machine shop.
Small World! I used to live in West Palm - Just have Kovacks build the whole thing for you. He will do it right. Problem solved.

Is his shop still in the sketchier part of town?

- Paul of Mo
 
Are you going to be putting the parts together or are you going to have the machine shop that does the work do it for you?

I'm not able to do the work on this. Car is at my mechanics and he will drop off engine. This will add cost. I have done my homework on TEC here in West palm beach...they are a VERY highly recommend machine shop.
Small World! I used to live in West Palm - Just have Kovacks build the whole thing for you. He will do it right. Problem solved.

Is his shop still in the sketchier part of town?

- Paul of Mo
Kovacks or TEC? Most of the good shops here are in sketchy areas !



Are you going to be putting the parts together or are you going to have the machine shop that does the work do it for you?

I'm not able to do the work on this. Car is at my mechanics and he will drop off engine. This will add cost. I have done my homework on TEC here in West palm beach...they are a VERY highly recommend machine shop.
Small World! I used to live in West Palm - Just have Kovacks build the whole thing for you. He will do it right. Problem solved.

Is his shop still in the sketchier part of town?

- Paul of Mo
Whoops! You meant Mike Kovacs of TEC! Right? Unfortunately I already have Rick from Ricks Rods involved, so he's pulled the engine and it's getting over to TEC today. I'll have Rick get the engine back in and finish the Carb and intake
 
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Paul had lots of great advice for sure.

I just wanted to comment on the use of the high octane fuel. The use of a higher than needed octane will add heat to the engine and not much else. If you do not spark knock on 85 octane without methanol I would use it. I was engineering manager at the largest lawn equipment manufacturer in the U.S. owned by Husqvarna. I also did lots of work with John Deere on everything from lawn equipment to their largest tractors. They both did lots of testing in the lab on fuel and the effects of different octanes. I have seen turbos glowing red for days. They both found that using a higher octane fuel actually hurts the life of an engine due to the higher burn temp of the higher octane. If you do not need the higher octane then do not use it.

I am a little torn on the hardened seats. Yes they are better but are they needed? When you put the insert in the heat dissipation from the seat to the head is not as good a just the head being the seat. Yes the seat is made from material to stand the higher heat to offset that. I have a 1956 Ford Club Sedan 292, 4-V 3 speed overdrive. It has just over 100,000 miles on it and was a one owner car. I did all the mechanic work on the car for the original owners that were neighbors and bought the car from them. They only used Pure White Gas in the car. Pure was the first to have unleaded gas since maybe in the 50's.

This car never had the heads off of it and ran fine when put in the barn to rest, lol. It was ran hard they would go to Key West for a 3 day weekend driving from N.C. and would run over 100 most of the way. The car would do 70 in 1st. gear in overdrive. So it was ran hard and valves had no issues with unleaded then.

I guess for peace of mind you can install but it is just another possible point of failure if they don't get the bore dia. right for the insert and shrink them in correctly. They can come out.

Just more food for thought. Sounds like you are going to have a great engine.

Another point I might make is if you use Forged Pistons you need to let the engine warm up longer before putting a load on it to prevent getting cracks in the skirts. Cast Pistons use less clearance and are less prone to cracks but will not stand up to the punishment of racing as good as forged.

Also I did not see in your list to balance the rotating assembly from front pulley to driveshaft. This will add life and be really smooth running. It should not be a great expense.

David

David

 
The kit you linked at Summit has a 2V intake set. Is that what you need? It also states estimated compression ratio with a 55cc chamber???????? There are no OEM 351C heads with a chamber that small. If your machine shop is familiar with 351C performance engines, let them help with parts selection. If they are not, find a performance machine shop that is. If they do not have deck plates for a 351C to use for boring and honing the bores, find a shop that does. Good parts can not make up for mediocre machine work. You do not want to use the 1973 dished piston and resulting compression ratio of 8.0:1.

Look for a flat top piston. Beware of different "compression distances" from different manufacturers, it changes compression significantly. Be aware Ford varied block deck heights to alter compression to "meet emissions". You do not want to end up with a piston that is way down the bore. It decreases compression and increases the chances of detonation. Aim for a "near zero deck" that puts the top of the piston no more than .010 down the bore when the piston is at TDC. With a 76cc chamber and a .041 head gasket this should yield an approximate static compression ratio of 9.15:1. This will allow the use of a camshaft with enough duration and resulting overlap to make use of the 4V heads.

Lunati has two factory style cams for 351C 4V. Either one would work, be easy on the valve train, and allow the use of OEM sled style rockers if you want to do that. If you want roller rockers, the Scorpions are good quality and value. I'm sure others make factory style cams as well. Talk to Lunati, Schneider, Bullet, Comp, even Elgin Industries if the budget gets tight.

The 4V heads do not need a lot of duration and resulting overlap but, they do like significant lift to utilize the flow potential of the head.

The Hooker Comp header works well, fits well, and is not crazy expensive.

The Edelbrock air gap intake would be a good choice. As would a 70-71 factory 4v intake if the budget is tight (the primaries need to be slightly enlarged with a sanding roll to match the secondaries).

Consider a Quick Fuel 750 vacuum secondary street carburetor.

Have a distributor shop recurve the distributor to 20 degrees mechanical advance, all in by 3000 RPM. Limit any vacuum advance to 10 degrees, set initial to 16 degrees.

Good luck with the build. Let us know how it turns out. Chuck

 
The kit you linked at Summit has a 2V intake set. Is that what you need?

sorry..thats the type of kit I would use to keep costs down...per another members instructions. Obviously would need 4v gaskets etc... And machine shop would match all this stuff based on the work and measurements they get paid to do!! I hope!


My first inclination :

headers:

http://www.jegs.com/i/Hooker-Headers/520/6915/10002/-1

Intake

http://www.summitracing.com/parts/edl-7564?seid=srese1&gclid=Cj0KEQiA-4i0BRCaudDcrrnDi6kBEiQAZSh5fwkPwLS4z242IR2llUye50ZYOoK452Fj96IMCxzK4wkaAnPc8P8HAQke:

Carb:

http://www.amazon.com/dp/B00A1GFXVO?tag=viglink22300-20
 
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The kit you linked at Summit has a 2V intake set. Is that what you need?

sorry..thats the type of kit I would use to keep costs down...per another members instructions. Obviously would need 4v gaskets etc... And machine shop would match all this stuff based on the work and measurements they get paid to do!! I hope!


My first inclination :

headers:

http://www.jegs.com/i/Hooker-Headers/520/6915/10002/-1

Intake

http://www.summitracing.com/parts/edl-7564?seid=srese1&gclid=Cj0KEQiA-4i0BRCaudDcrrnDi6kBEiQAZSh5fwkPwLS4z242IR2llUye50ZYOoK452Fj96IMCxzK4wkaAnPc8P8HAQke:

Carb:

http://www.amazon.com/dp/B00A1GFXVO?tag=viglink22300-20

The parts you have listed are fine.

For the rest of the hard parts I would just let Mike get them for you. He knows what he is doing and knows what he likes when assembling a long block.

- Paul of Mo


I have used this ebay vendor for the last 3 engines I have put together and have no complaints.

All parts are name brand and he will swap out items if requested.

http://www.ebay.com/itm/Ford-351C-1970-73-Engine-Kit-pistons-gaskets-rings-bearings-Se-Habla-Espanol-/151352325402?hash=item233d4d351a:g:btAAAOSwEK9Tv9xA&vxp=mtr

I would swap out the HV oil pump for a standard one - other than that this is about as complete as you can get.

- Paul of MO
 
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The parts you have listed are fine.

For the rest of the hard parts I would just let Mike get them for you. He knows what he is doing and knows what he likes when assembling a long block.

-

- Paul of MO
Thanks Paul! Thats exactly what Ill do !!



The kit you linked at Summit has a 2V intake set. Is that what you need?

sorry..thats the type of kit I would use to keep costs down...per another members instructions. Obviously would need 4v gaskets etc... And machine shop would match all this stuff based on the work and measurements they get paid to do!! I hope!


My first inclination :

headers:

http://www.jegs.com/i/Hooker-Headers/520/6915/10002/-1

Intake

http://www.summitracing.com/parts/edl-7564?seid=srese1&gclid=Cj0KEQiA-4i0BRCaudDcrrnDi6kBEiQAZSh5fwkPwLS4z242IR2llUye50ZYOoK452Fj96IMCxzK4wkaAnPc8P8HAQke:

Carb:

http://www.amazon.com/dp/B00A1GFXVO?tag=viglink22300-20

The parts you have listed are fine.

For the rest of the hard parts I would just let Mike get them for you. He knows what he is doing and knows what he likes when assembling a long block.

- Paul of Mo


I have used this ebay vendor for the last 3 engines I have put together and have no complaints.

All parts are name brand and he will swap out items if requested.

http://www.ebay.com/itm/Ford-351C-1970-73-Engine-Kit-pistons-gaskets-rings-bearings-Se-Habla-Espanol-/151352325402?hash=item233d4d351a:g:btAAAOSwEK9Tv9xA&vxp=mtr

I would swap out the HV oil pump for a standard one - other than that this is about as complete as you can get.

- Paul of MO
Do i need to supply my mechanic with any additional parts for these?

Looks like the intake requires bolts??

Gaskets for everything?
 
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