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Wesman07

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Its a bit early to start a thread but I think good planing will be beneficial. If all goes well, we will be buying our first house this spring and I will finally have a garage again. I am trying my best to hold off on picking up an engine until we move because I don't like to move things twice.

This week I paid a visit to our local engine builder, M & S Engine Works in Sandpoint Idaho. I heard about them from another member on this site who said they hone with a torque plate. Small world. Very pleased with who I met and what I saw. I had no intentions of letting someone else put together the rotating assemble, but its sounds like that is the most practical way of doing things.

Ok so big picture. This motor will be going in truck that will be used like a truck. Reliability is the most important with longevity following behind. It also must pull a decent size trailer, so it will see long duration's of boost on occasions. The way I would like to address these demands is the same way I would like to tackle cost control... Stick to the original design intent as much as possible.

I want this motor to run off the lowest octane fuel available. Some of the gas stations in my area do not have octane options. It will also keep me from getting mad at my wife, if she was to forget lol. RPM will be limited to 4,500 in order to use the stock connecting rods. Valve lift will be kept under .450" and the cam lobe ramp will be relatively mild for valve train longevity and cost control. Pistons will likely be a custom forged set from Auto Tech, which is a relatively small price to pay for a big win in reliability.

As of now this is the plan, but I'm open to suggestions:

87-96 block (for knock sensing)
Honed with a torque plate (To keep blow by to a minimum)
Rods will get ARP bolts or equivalent (for the increase in RPM)
Forged pistons (7.8-8:1)
Carb head (for the camber volume) I am open to other ideas.
The Camshaft I am looking at is one of Howard's "stock lobe" grinds. 1hs206278 - 270@.006, 206@.05, .278 lift, 114LSA. That should be a 42.1% ramp. Stock is 30.9% and most aftermarket lobes are near 50% ramp
Spark/fuel/boost will be controlled by Holley HP, utilizing a TFI distributor.
An air to air intercooler will be used but I don't know what size
Turbo will be a BW s200 sx-e 70s75 twin scroll
The exhaust will be a divided stainless log style, with dual waste gates
I think this will be close to 500ft/lb, 300hp mark
 
Looks very good
Great choice on the turbocharger.
Any head porting and/or larger valves?
 
Its a tough call on the head. From what I can dig up, the carb head flows much better at low valve lifts and simply cleaning up the bowls does a good amount. I don't know if larger valves are worth it for the rpm it will see. As of now I am looking at roughly $1,000 for the bottom end work plus parts. What do you think the head will need? Valve material? seals? seats? Can i use a CG rated head?
 
The larger intake valve will offer more power after 3000 rpm.
If you need new valves anyway it is not much of an extra expense.
You should do exhaust valve seat inserts and possibly stellite exhaust valves since the engine will see extended periods of boost.
I like to use positive stop Viton valve stem seals
 
knock sensors...
how come I'm believing it was the later years had knock sensors.
I have not heard they installed them as early as 87.
 
sdiesel":jzm3p5f3 said:
knock sensors...
how come I'm believing it was the later years had knock sensors.
I have not heard they installed them as early as 87.

To my knowledge all fuel injection 300 came with knock sensors. Located above and behind the oil filter.
 
The knock sensor location is up and to the right of the blank fuel pump boss.

If you are doing sequential fuel injection would you consider a coil near plug ignition system?
 
Nothing against coil near plug. Is the pay off really worth the added expense? I would also have to rely on an additional sensor...

Ford ran sequential injection off the tfi in 96. What was wrong with that?
 
The PIP signal from the TFI distributor contains both the Ignition timing and cam sync information so no other sensor is needed to do sequential injection or sequential distributorless ignition. The Holley HP can decode the PIP signal.

The six (coil near) coils are triggered directly from the Holley HP meaning you don't have to supply anything else to complete the ignition system.
The goal is to eliminate the distributor cap and rotor which have been giving a lot of trouble lately in high energy ignition systems being used in higher mileage daily drivers.
It also eliminates the need for rotor phasing which cannot be done with the TFI distributor.
 
Sounds like a good idea. I’ll have to see how much the motor cost before I can make that call. It looks like $500 in coils.

Question on the bottom end. How low can we get the compression down with a custom piston on a stock rod? Is an efi style head out of the question?
 
The CD on a piston for a stock rod is 1.80" leaving plenty of room above the connecting rod for a deep dish.
The 300 carb head has around an 80 cc chamber if it is relieved needing a piston with a 30cc dish to get 8:1 at zero deck.

You can easily relieve an EFI head chamber out to 70 cc where the piston dish would be 40cc for 8:1
Here is what a 40cc dish looks like.
https://www.summitracing.com/parts/slp- ... /make/ford
 
Good to know. Does it make sense to set the motor up for an EQ head?

It “should” be an increase in fuel economy.
When Gramps JR head is available, it would be a direct swap.
 
Wesman07":3fcm68bg said:
Good to know. Does it make sense to set the motor up for an EQ head?
It “should” be an increase in fuel economy.
When Gramps JR head is available, it would be a direct swap.
Good question as you need to have a cylinder head before you can order pistons and also make manifolds.

If you are for sure going to eventually use the Gramp's JR head then you will need to use an EFI head in the short term to match the combustion chamber volume because of the piston dish volume.

The EQ heads that Gramps checked were coming in with 64cc chambers which is less than the Ford 68-69cc chambers.
One of the first JR heads had a completed chamber volume of 68cc.
If you purchase an assembled EQ head you will want to do some valve unshrouding and get the chamber volume up to 68cc.

The springs will also need to be changed to match the cam profile.

Is the combustion chamber modifications something you can do?
Any other thoughts?
 
I have no problem doing some hand work. Its the machines that I don't have. What I'm trying to do is keep this project reasonably priced.

So far I'm looking at:
$1,000 in machine work on the bottom end
about $1,000 in pistons and bearing
$2,000 for the Holley HP and wiring
over $1,000 in Turbo parts

I would like to pick up one of Gramps head in the future, but that would be way down to road for me. My machinist said the head is where it gets expensive, so I'm looking into alternatives. I need the torque. I would like the horsepower.

The ATK head looks like cheapest rebuilt head on the market. At $300, I cant imagine it is very good.

The EQ head is about $300 for casting/ $600 complete

I called Sage about their ramptech heads, they are about $700 complete


Does the EQ head come ready to assemble? Can i pick up the ch300b head, do some hand work to the chamber and bowl areas, then have seats installed?

Do you see another area I can cut costs? I can't imagine that putting a crank in myself and filing rings would save much.
 
After some thought I remembered that one of the problems with the stock EFI valves is that they are short and make it difficult to find a valve spring to work with such a short installed spring height.
You want an installed spring height close to 1.700"
The valves on a turbo engine are trying to close against pressure on both the intake and exhaust so you want good seat pressure but you don't need a lot of open pressure for rpms below 5000 rpm.

Having said that it would be far better to get the bare head instead of the assembled head and install seats and longer valves.
You would do you own bowl blending and chamber modifications.
Chamber work can be done first but you have to wait until the valve seats are done to do the bowl blending where you have to be very careful not to touch the 3 angles on the valve seat.
If you do the larger intake valve I believe you would not need an intake seat insert and would just cut the seat angles on the existing casting.

The work is usually done with a long nose die grinder and burrs and using an electric grinder with a foot pedal can make control easier.

Another though is if you are buying an EFI long block as your rebuildable core and the head checks out OK and is free of cracks, modify it for the project.
 
Questions:

1) What defines the installed spring height?

2) To increase seat pressure without increasing open pressure much, you would need to add pre-load. This typically makes coil bind happen sooner. Longer valves and springs should help that, correct?

3) I was under the impression that hardened valve seats were strongly recommended. Am I wrong?

4) If i went with an hardened seats, can't I remove a hair off the O.D. of an extra seat and use it for porting mock up? The idea is the good seats can be installed after porting.

Good idea on checking the stock head. Sounds like its a 50/50 shot, but do you think the factory casting will hold up?
 
To answer question 1 and 2
Yes a higher installed spring height gives more margin to spring bind but it also widens the selection of springs available to get the job done.
You can always shim the spring tighter to get the correct seat pressure if the retainer is high but you are stuck if the retainer is too low to use any of the catalog springs for the correct seat pressure.
You use the installed height spec of the spring to get your seat pressure and the spring rate determines the open pressure at full valve lift.
Then you make sure there is at least .060" clearance before coil bind at full valve lift.

Typically the street hydraulic cams for the 300 six call for a seat pressure around 110 to 115 lbs with an open pressure in the mid 200s.
When you look through the springs charts in the various catalogs you will see that spring pressures at 1.60" are very high and in most cases too high.
If you look at pressures at 1.70" instead there is a variety of springs that will work.
If the spring perch on the head is machined flat so you can use a double spring or a beehive spring then the possibilities increase again.
Most springs have a recommended installed height so they can meet the advertised valve lift without running into coil bind but you can vary from that to meet your needs.
Hope this helps answer "what determines installed height".

Question #4 is a good idea but you will still need to blend the permanent seat into the bowl area after it is installed.

Hardened seats is usually a concern with the smaller and hot exhaust valve.
The larger diameter intake valve puts less pressure on the seat and the intake valve rarely shows recession into the head.
It certainly doesn't hurt to have a hardened intake valve seat but the larger intake valve may not allow a larger seat pocket to be cut without running into the water jacket.
This would be a good discussion to have with your machinist.

If you find a good factory head they seem to hold up OK.
AFAIK no one has reported a failure on a good rebuilt head.
The only consideration is that a finished factory head will have more chamber volume than a JR head and the head swap would raise the compression.
 
Thank you for the explanation on valve springs. The theory’s seem like they correlate with what I know from suspensions, the lingo and the way they judge springs is just a little different.

I like how seat pressure and installed height is focused on. “Open pressure” is where I find spring selection a little misleading. Your description was good, I’m talking about advertising. In my eyes frequency is the important number and what should be listed on the charts. As you move to a steeper ramp lobe or spin it faster, you need a higher frequency (faster reacting) spring to stick with the cam lobe.... which is also a higher spring pressure. It’s just a round about way of saying the same thing.

You seem pretty certain that the intake valve needs to be bigger, even on a motor spinning to 4500rpm. I’ll take it. 1.84” sounds like that’s all I’ll need, correct?

For the exhaust side of things, I’ll have to go with a log style manifold. The turbo will need to be held tight to the block to keep clear of the wheel well. I’m hoping to be able to mount the turbo between cylinder 3 and 4, but I am not positive it is possible yet. I will need to fit a coil-over shock and possibly an external bypass shock in front of the heater box. I am trying to keep the shocks back on the control arm to cut down the effects of friction. Basically, from the frame rail up to the intake manifold split will be used. Here is what I’m thinking to use for the exhaust manifold https://www.aceraceparts.com/collection ... 6639663812

90 down off the head, 90 in on the ends, use T’s in between. Split the front 3 from the back 3. I will be running a reasonable sounding muffler. I’ve had good luck with the flow master 70 series.

How do you suggest I address the exhaust side? Valve size? Exhaust lobe duration?
 
Just to add to the spring conversation.
As you have already figured out, open spring pressure is seat pressure plus the (valve travel multiplied by the spring rate)
Max reciprocating valve frequency can be increased by spring pressure or by decreasing the reciprocating mass such as lighter components including beehive and conical springs which also use very small spring retainers.

Street hydraulic cams for the 300 six rarely need an open pressure to exceed 300 lbs.
If you move to solid lifter cam which typically has a more aggressive ramp rate then pressures on both seat and open will need to be increased.

On intake valve size; the 300 six having large 50 cu inch cylinders is choked by the small intake valve.
The stock head and stock cam show peak volumetric efficiency around 2000 rpm and many report a fast power drop after 3000 rpm.
If you look at the many 300 builds using big valve ported heads, they report large torque gains from off idle and significant tire turning torque from 1000 to 1200 rpm and that is using cams with much more duration than what you will need.
A 1.84" intake valve will do just fine.

We can discuss cam profile for your application later.

If it is possible turn the 90* elbows so they approach the main log in the direction of the exhaust flow.
Here is the Hooker turbo exhaust manifold as an example:
https://www.summitracing.com/parts/hok-8510hkr/
 
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