New FE build BBM block and heads

[jkg2101]

I thought I would put together a posting about my FE build. I am putting this engine in a Kirkham cobra. This has been a long dream of mine. Maybe others will find this info interesting or even useful.

I have built several older cars for myself over the years (small block fords, small and big block chevys). I have come to several conclusions regarding my hobby cars:
1. If I want to race or be really fast, I’ll use a new corvette. Older cars are not as safe or capable in most cases
2. I like sound and feel. So good torque and lots of noise makes fun for me.
3. I like reliable. I don’t like when my MSD distributor failed at 1000 miles, or my electric fuel pump died after a year. I tend to keep things simple and reliable for more fun.


So I found Blair Patrick down in Tennessee. He is great to talk to and extremely knowledgeable. There are other good engine builders out there, and some on this forum, so no offense to others, but Blair worked well with me. He certainly has proven himself in the world of the FE.

I like assembling an engine. I can’t do the machine work. Blair assembled the short block and heads, and then I put it all together. Blair and I agreed on an iron block from BBM. I don’t want to spill over onto the painfully long thread about aluminum blocks, but I didn’t feel a need to use aluminum block to achieve my goals. I know the weight savings won’t be meaningful to me. Others can have their own opinions.

I wanted to keep the stroke small, to allow the engine to rev better. I will be equally happy on the street with 400 or 500 horsepower, and with less stroke, there is less stress on the rotating parts and maybe more revving. It is fun to rev an engine past 6000 rpm.

Stock stroke on a 427 is 3.78”. Scat and RPM don’t make forged cranks in that stroke. You can get a custom one done, but the price becomes much higher. So I went with RPM motorsports 3.98” stroke forged crank. Made offshore (in china I think), but machined nicely by Blair, who knows what to do to make this brand work in a new build. 4.25” bore for the pistons. Something like 450 cubes when done.

The original sideoilers came with solid non-roller lifters, which is an option, but seems smarter with modern oils to use roller lifters. I chose hydraulic roller lifters (the BBM block does have oiling to the lifters available, both through the pushrods and separate passages through the lifter bores). Blair recommended limited travel hydraulic roller lifters from Morel. Very expensive but beautiful pieces. They really do have limited travel to the plunger. I suspect they work like a solid once you get going, but don’t need to check valve lash too often.

When you set the "lash" with the rocker arm, if you go a full 3/4 of a turn, you will bottom out the plunger, so need to add less preload to these lifters than you might normally do for a hydraulic.

Blair came up with a custom cam for me. His trade secret I suspect.

For heads, I went with BBM aluminums, with limited port work by Blair. Some nice gains in power over stock iron heads here, although you could argue it is all overkill for a street car that weighs 2000 pounds. Aluminum heads may allow a little more compression on pump gas than an iron head, and probably better power at all rpm. You could say I am hypocritical for going with iron block but the aluminum heads, but I think there is a lot more bang-for-the-buck in heads vs. the block itself.

We put restrictors in the oil passage to the heads, to limit oil flow to the rockers. I also used solid pushrods to limit oil up top. I used 5/16” pushrods, the beefiest ones I could order, to minimize any interference with the pushrod tunnels in the intake. Edelbrock performer RPM intake because it is the easiest to find. Blair recommended port matching the intake to the heads, but I didn’t because this is probably overkill for my intended purpose (just my opinion).

I went with T&D roller rocker system. Not their super fancy race system but the less fancy system that does not require special machining of the head. Trust me, it is plenty fancy! Very nice setup and only a few bucks more than competitors. Just as beautiful as the lifters.

These are roller lifters, unlike stock, so need much less oil than stock rockers. Stock lifters and some aftermarket are bushings, not roller bearings. Bushings are probably adequate for most things, but need more oil than roller bearings.

The only trouble I had assembling the whole thing was with the rockers. On an FE, you have to tighten down the rockers against the valve springs. I used nice studs in the head, with custom washers and nuts from Blair. But I got a little too vigorous on one of them and pulled the threaded insert out of the aluminum head. I had to repair it, by drilling the threaded insert out of the head and replacing it with a bigger threaded insert. I can explain more if someone wants to discuss. That caused me a lot of stress for a couple days.

The bottom line, is that aluminum is more delicate than iron, and you have to be meticulous in technique of torqueing. You have to tighten the rocker studs evenly and very carefully, against a good bit of valvespring pressure.

I went with a moroso oil pan (road race version) and a nice melling oil pump with hardened shaft, blueprinted by Blair. The moroso pickup for the oil pump sits a little too far from the bottom of the pain when a windage tray is used, so I skipped the windage tray. Blair normally modifies the pickup arm to be closer to the bottom of the pain when he does the build using a windage tray.

When I oiled the engine prior to start-up, i was amazed at how quickly oil came up to the heads. On other engines, quite a bit of priming is needed to get the oil through the engine. On these FE's, they really do put a lot of oil to the heads, so much so that I can believe running at high rpm can empty the oil pan and drown the heads.

The stock FE's back in the day used special metal trays to direct oil back into the block. These trays won't fit with aftermarket rockers. Even with non-oiling pushrods and restrictors in the head passage on both sides, there is PLENTY of oil to the valvetrain.

Used a romac balancer – very nice piece. I prefer these made in australia units to the cheaper made in china ones from other brands. Romac makes a nice repro unit that includes a single bolt-on integral pulley, as the originals did. Using original distributor with dual points. Yes points are not modern but I’m doing it anyway. Points can fail, but I have been happy with them on other cars, and I hate how my MSD magnetic pickup in my Pantera failed out of nowhere with little use… I’m not the only one to have such a failure.

Just getting the engine in the car now. Should be stupendous once it actually starts!

[jkg2101]

Here are some pics of engine and the car ready to receive its heart!

[jkg2101]

just for fun, here is an image of the restrictor in the oil passage to the rockers, in the head. the big main hole is where the stud goes to mount the rocker shaft, and the small hole off to the side is where the restrictor is threaded in

[jkg2101]

here are a couple pics of the engine during assembly. i didnt really take enough photos to give a play-by-play

[Large Arbor]

Very nice looking build!

Phil

[bill37341]

You should have let Blair build a 7-800 hp monster for you. He is one of the best known builders in the FE world. Super nice guy.

[Dimis]

Well played Sir.
Nice choices all round.
I trust she'll serve you well and perform flawlessly

[SFSDFGT]

Looks fantastic!

[RodKnock]

Nice Kirkham. And I like the garage too. Clean!

[jkg2101]

thanks for the kind words

i was too cheap to buy those racedeck floor tiles. they just add up really quickly.

i have epoxy on the floor in the other parts of my garage, but in my car restoration area, i just bought some cheap black and white vinyl tiles from menards (I think) - self stick. they work well for a few years and then start to fall apart. i think the previous set i got from lowe's or home depot. they go about 6 years and then i throw them away and start over. they ran about $1 per foot last time around.

[RodKnock]

BTW, is that an Armando or Aviaid pan? Or maybe something else?

[jkg2101]

As much as I would have liked an original-style armando or aviad oil pan, i had to cut costs somewhere, so I got a moroso road race pan. it seems to have nice baffling and was much less expensive

also it sounds silly, but the original pans take several more quarts of oil, and that just means more expensive oil changes when the time comes.

yes, i am a penny pincher, which is not logical, since nothing on the car is really inexpensive!

bargains on this engine: distributor is an old unit I rebuilt, and added a steel gear, which I found in my dad's old collection of parts.

valve covers are swap meet finds for $50 - sandblasted and painted, also added baffles under the vents

timing cover, alternator brackets and alternator came out of my dad's collection of FE parts (he has built a half dozen over the last 30 years for various mustangs and even an R code galaxie!)

remaining purchases: carburetor (probably will go with 850 holley or quickfuel); starter (looking at RobbMC or powermaster)

[RodKnock]

All seems reasonable to me. You know what you want, you have a plan and you're firm in your decisions. That's great!

Could we here at CC interest you in some Weber carbs or an 8-stack EFI?

What KMP # is your Kirkham?

[jkg2101]

855

i did EFI on my pantera. i ended up with not the best system. It was 10 years ago. i know a lot about it if anyone has questions. although it offers interesting opportunities for knowledge and tweaking, after 3 years I removed it and added a 750 holley carb. It runs every bit as good as the EFI ever did.

Others have been more successful with EFI. I will admit that.

The challenge with EFI, in my opinion, when it is working, is that it is hard to set your goals. In other words, i can set the target AFR to 13.8 or whatever, but who says that is what is best for this particular engine? need time on a chassis dyno to really do it great. vary rpms and loads, and then you have to add in environment (intake air temps) and things to really be great. I am amazed at how much data a new car uses to optimize the fuel and ignition.

The big car companies have the resources to make EFI really work great. For me, the self tuning never was all that spectacular, and a lot of the same principles go into tuning a carb, which is less expensive. definitely i was discouraged because there were some technical problems with my system

bottom line was that i spent a lot of my driving time trying to tune the EFI instead of having fun. it was tough to finally admit defeat and switch to a carb

As far as webers, i thought about that a lot. Really would love to do one day. just they are super expensive. and then there is the theoretical issue that they actually may limit CFM on a big cube engine compared to a big carb. Lots of discussion on that topic on the pantera forum a bunch of years ago. i dont't know.

[Dimis]

Originally Posted by jkg2101

855

i did EFI on my pantera. i ended up with not the best system. It was 10 years ago. i know a lot about it if anyone has questions. although it offers interesting opportunities for knowledge and tweaking, after 3 years I removed it and added a 750 holley carb. It runs every bit as good as the EFI ever did.

Others have been more successful with EFI. I will admit that.

The challenge with EFI, in my opinion, when it is working, is that it is hard to set your goals. In other words, i can set the target AFR to 13.8 or whatever, but who says that is what is best for this particular engine? need time on a chassis dyno to really do it great. vary rpms and loads, and then you have to add in environment (intake air temps) and things to really be great. I am amazed at how much data a new car uses to optimize the fuel and ignition.

The big car companies have the resources to make EFI really work great. For me, the self tuning never was all that spectacular, and a lot of the same principles go into tuning a carb, which is less expensive. definitely i was discouraged because there were some technical problems with my system

bottom line was that i spent a lot of my driving time trying to tune the EFI instead of having fun. it was tough to finally admit defeat and switch to a carb

As far as webers, i thought about that a lot. Really would love to do one day. just they are super expensive. and then there is the theoretical issue that they actually may limit CFM on a big cube engine compared to a big carb. Lots of discussion on that topic on the pantera forum a bunch of years ago. i dont't know.

Dude, you're makin' a lot of sense.

I agree with you 100%, on the whole, these cars see such little driving that messing around with EFI is often not really worth the effort, or expense.

Don't get me wrong, I still often find I'm talking myself out of moving to an EFI. While the theory suggest I'll have a better engine package with the more precise fuel supply EFI provides blah, blah, the practical reality is the controlled leak of carbs suits equally well, without the headaches for my particular application.

As for webers, I'll admit I'm also tempted. However, yet to bite the bullet.
While the "theoretical issue" about limiting CFM on a big cube engine, may be true, I don't believe it matters.
We are unlikely to be driving our cars at that end of the RPM range where it would matter. ie: Top end, flat stick on a circle track.
We are more inclined to be driving it with varying, transient throttle inputs ie: low & mid RPM, and that is where webers IMHO would be advantageous to a single carb, even more so on a large cubed engine.
I've no data to back this up, but that is merely what I suspect I'd see.
Its all about combination and being fit for purpose.

[RodKnock]

Hey, I got a carb. There's something about the simplicity of a turkey pan and carb.

I mentioned the Webers and EFI as a tongue-in-cheek comment.

When was 855 delivered to you? I'm kinda curious how far along Kirkham is in building Cobras.

[jkg2101]

great minds think alike

i am pretty sure when I get my 289 cobra, i will build a small block with webers. that is really the car for it in my opinion!

It's good and bad that the cars I had on my walls back in my youth are now the hot collectibles (cobra, shelby mustang, ferrari testarossa)

The only one that hasnt completely gone crazy with price is the 70's era lotus esprit. unfortunately, when you learn about them, they are not much of a car for a performance-minded person. no offense to anyone who has one. i would still take one if someone handed it to me.

[Phx Mike]

Nice car and engine! I have #845 btw and got mine back in April. My 482 has a quick fuel 780 with vacuum secondaries and it seems just right for the engine. Great low end, good up at high rpm, crisp response, no flat spots, starts easy and no leaks anywhere. Just seems like a lot less hassle than sorting out the EFI.

[jkg2101]

some updates regarding the engine build

if anyone uses an RPM crankshaft in the future, be aware:

I know Blair had to do some work with the crankshaft to get the bearing sizes just right. i know he did a good job, but if anyone is thinking of using one of these in the future, keep in mind they are not plug-and-play

i found that out on my end. actually on both ends of the crank. Both where the flywheel attaches, and the balancer on the other side of the crank, the surfaces were machined with a tiny lip. just enough to completely keep the flywheel or balancer from going on at all. i had to use a flap wheel to lightly hone the inside of both the flywheel and the balancer, BUT the big helper was using a piece of sandpaper to take the tiny lip off the edge of the crank ends. then everything went on as supposed to (the flywheel just pushes on but the balancer needs an installation tool.)

i haven't put the pilot bushing in the end of the crank yet, but I can't wait. (that's me being sarcastic.) On previous aftermarket cranks (a Scat in a chevy), I had some trouble getting it in place. once in place, the pilot bushing somehow compressed just a bit, so the transmission input shaft bound up there. so when I started the car, it wouldn't go in gear because the trans was locked to the crank, regardless of what I did with the clutch. it took me 3 times in and out with the trans before I figured it out. that sucked, but at least it is easy to remove a muncie (light aluminum) from a 57 chevy (nothing but space all around). I hope I don't have to remove the trans from the cobra. looks like no fun.

on kirkham's assembly posting here a few years ago, notice how they had trouble getting the pilot bearing in the end of the aftermarket crank. For some reason, the hole is not milled correctly on many of these it seems. i'll let you know when i cross that bridge.

the moral of the story is aftermarket parts often have fitment issues. My last project was a completely stock Big block chevy with all original parts. everything fit nicely. EXCEPT for the one and only aftermarket piece - power steering pump bracket (the original broke) -

[lovehamr]

JKG, looks like this is going to be a great build! For what it's worth, it seems like I went through many of the same decision making issues that you are so take these for what they're worth.

Originally Posted by jkg2101

As much as I would have liked an original-style armando or aviad oil pan, i had to cut costs somewhere, so I got a moroso road race pan. it seems to have nice baffling and was much less expensive

I started out with the same pan, still have it on a shelf. If you're not going to be experiencing sustained lateral Gs it'll probably be fine. With mine, I'd start seeing the O/P gauge waver even on long freeway ramps. On actual road race courses it was totally unsatisfactory. I wound up picking up a used Aviad from Kirkham and never had another issue.

Originally Posted by jkg2101

bargains on this engine: distributor is an old unit I rebuilt, and added a steel gear, which I found in my dad's old collection of parts.)

I started out with a dual point dist with one pair of points backed off to trigger the MSD hidden under the dash. When I switched to a mag triggered unit that still looked vintage I couldn't believe how much it helped.

Originally Posted by jkg2101

valve covers are swap meet finds for $50 - sandblasted and painted, also added baffles under the vents) timing cover, alternator brackets and alternator came out of my dad's collection of FE parts (he has built a half dozen over the last 30 years for various mustangs and even an R code galaxie!))

All of those are great calls. I had lots of used stuff powder coated and that has worked great for me.

Originally Posted by jkg2101

remaining purchases: carburetor (probably will go with 850 holley or quickfuel); starter (looking at RobbMC or powermaster)

I started out with a 950 Demon which I'd run on a previous car and it's a great carb but with the Cobra it'd choke me out of the garage while idling and I always smelled like gas when I drove it. Then I switched to an FI unit that looks like a single 4 carb. I must admit that the learning curve was steep and the forums invaluable but once it was set up correctly my god it was like a different car! I could stand outside the car and start it cold, it wouldn't choke me out of the garage, it didn't smell at all while driving and mileage (not like I was really looking for it) nearly doubled.

Good luck man. I'm enjoying you build!

Steve