Another 400 build thread

[blackhand]

About this time last year I decided to replace the stock valve springs on my 400 with a set that better matches the cam. Well, plans change I guess and a year later the engine is still on the stand with much bigger things in store for it.

I've decided to go with new heads, rockers, cam and lifters, torque converter, headers, and exhaust. It's going to be a big project but I am well on my way and hope to finish things up by next spring. It has killed me to have the car off the road for a year already and it's going to be another long year without driving it, but I suppose that's all part of the hobby! Anything worth having is worth waiting for, as they say.

The engine ran well before being pulled, it only has about 40,000 miles on it. The car was running 14.6 in the quarter mile, not too shabby for a lowly smog motor. As you can see, it was mostly stock with a few bolt-ons.

With the engine out, it was a perfect time to get rid of the Chrysler Blue and spray a new coat of Hemi Orange. The blue paint was holding up OK, but it was chipping in some areas. I removed the loose paint with a wire brush, scrubbed it down with engine degreaser, gave it another scrubbing with warm water and dish soap, and finally rinsed it with plain water and used compressed air to dry it. I carefully masked all areas not receiving paint.

I applied about 5 or 6 very thin coats of Plastikote. I've heard nothing but good things about this paint and so far I am very pleased. It goes on thick and has a nice gloss, very sharp looking in my opinion.

After painting I decided to clean up all of the bolt holes on the engine. I went to my local Napa and picked up a selection of Grade 8 bolts. A few slices with a diamond wheel on my Dremel gave me some nice homemade thread chasers. They work beautifully. I chased all of the holes on the engine until I was able to thread a bolt all the way in and out using only my fingers. The threads feel very clean, no sticking points or anything like that.

 

[blackhand]

Now for the fun stuff:

I had originally planned on changing the valve springs and then port-matching the stock 452 heads to the Edelbrock Performer RPM intake manifold. While changing the springs I realized that the valve guides were a little loose. Rather than paying to have them fixed I decided to spend my money on a brand new set of 440source Stealth Heads instead. The heads look great, the casting in the ports is relatively clean and the bowls were cleaned up just a little bit by 440source. The ports and valves are massive compared to the stock 452s that they are replacing.

I chose all Hughes components for the camshaft and valvetrain. I will be using their Whiplash cam with 1.5 ratio cryo-treated aluminum roller rockers. They have modified the design of the rockers recently and I hope that they are as durable as the previous design (I'm sure they are).

I installed the cam with the dots on the gears aligned. After degreeing it in I found that it is within one degree of the recommended centerline, so no need to make use of the other keyways.

Hughes provides (for a refundable deposit) an adjustable checking lifter and pushrod. I set the plunger height on the lifter to match the race hydraulic lifters that I purchased from them and then adjusted the length on the pushrod to provide the greatest amount of lift as measured on the retainer. All I have to do is send the adjustable checking pushrod back to Hughes and they will make a custom set of pushrods to match it.

The rocker arm geometry seems pretty great right out of the box. Photos below are of the valve on the seat and at maximum lift. The scrub pattern is also shown in black ink on the valve tip.

 

[blackhand]

I will not be replacing any bottom end components at this time. I'll save that for a later date, after I recover from this investment. My plan for this build (for now) is to see what a stock 400 block and rotating assembly can do with decent heads and a well-matched cam. I have a feeling it will surprise a lot of people.

I also am anxious to see how well the Whiplash cam actually performs. I have heard a lot of good things about how it sounds, but pretty much nothing about how it performs. It's cool to have a nasty sounding engine, but I am much more concerned with my ETs. My stock, low-compression bottom end will be a great test mule for this cam.

 

[txstang84]

:blob: anxiously awaiting ETs! Looks pretty sweet-beautiful Barracuda btw

Wish I could send my brother your way for some help...he's up in Lake Stevens...

 

[bluenotefan]

Good stuff. I'm glad to see more 400's popping up on FABO. Hopefully I can gain some ideas about the direction to take mine. Nice looking Barracuda man. Keep us posted. :thumbup:

 

[blackhand]

anxiously awaiting ETs! Looks pretty sweet-beautiful Barracuda btw

Nice looking Barracuda man.

Thanks! It's my baby. Absolutely kills me to have it just sitting in the garage right now. I know it will be worthwhile when done though.

I'm glad to see more 400's popping up on FABO. Hopefully I can gain some ideas about the direction to take mine.

They pop up for sale quite often and are usually cheap as dirt. A lot of people write this engine off as a dog because it has low compression. This is true, but it also has 400 cubes! I'm very interested to see what the stock short-block will do with a good top end.

I'll definitely keep on posting as I make progress. Thanks for the words of encouragement!

 

[younggun2.0]

I think you are going to be very surprised how well it runs. I have a low compression 383 in my dart with some mild ported eddy heads and an m1 intake. I have a pretty big solid cam and it runs pretty damnable hard. Not been to the track yet but I think its a mid 11 sec car.

Its good to see another washington boy on here

 

[MTmopars]

Correct me if I am wrong, but aren't aluminum heads on a low compression motor a poor choice?? The thermal properties in effect lower the compression by reducing the heat.

"Aluminum heads dissipate (get rid of) heat much faster than iron heads. The rapid heat loss from the combustion chamber results in reduced combustion chamber pressures (heat equals pressure); similar to the effect that lowering the compression ratio which lowers cylinder pressure. When switching to aluminum heads you MUST raise the compression ratio to prevent a power loss."

"Aluminum heads will not automatically create more power than iron heads unless they flow more air and are installed on a higher compression ratio engine."

I was told by hughes over phone when discussing my 78 slogger 440 not to go with aluminum heads if not increasing compression by at least a point.

 

[william]

Correct me if I am wrong, but aren't aluminum heads on a low compression motor a poor choice?? The thermal properties in effect lower the compression by reducing the heat.

"Aluminum heads dissipate (get rid of) heat much faster than iron heads. The rapid heat loss from the combustion chamber results in reduced combustion chamber pressures (heat equals pressure); similar to the effect that lowering the compression ratio which lowers cylinder pressure. When switching to aluminum heads you MUST raise the compression ratio to prevent a power loss."

"Aluminum heads will not automatically create more power than iron heads unless they flow more air and are installed on a higher compression ratio engine."

I was told by hughes over phone when discussing my 78 slogger 440 not to go with aluminum heads if not increasing compression by at least a point.

I would say you're right but remember most if not all aluminum heads have smaller combustion chambers then the open chamber iron heads .Going from a set of 452 at 90 cc to 92 to the source heads at 80cc you will pick up the compression and flow better.

 

[younggun2.0]

I have a set of 84cc eddy heads on my car now. with my bore/gasket/ and installed height im at 8.98 static compression. my car still runs pretty hard.

 

[RustyRatRod]

Correct me if I am wrong......

You are.

 

[younggun2.0]

You are.

It is my understanding that the material of the head does not effect the compression rate at all. I believe that you are ABLE to get away with approx. 1 point more of compression with aluminum heads because they disipate heat faster and dont hold the heat like an iron head. when an iron head hold the heat it causes pre ignition or detonation.

correct me if im wrong. lol

 

[cdlbrown]

Pretty interesting read. "Iron vs. Aluminum Heads" at Car Craft Feb 2006
www.carcraft.com/techarticles/ccrp_0602_iron_versus_aluminum_cylinder_heads_test/index.html

 

[MTmopars]

You are.

My, aren't you charming. :violent1:

The quotes I posted were from a tech article on the Hughes Engines website. That is the reason I asked, and posted the quotes. I understand that the material does not effect static compression ratio.

More from Dave Hughes, "6. Power: Power depends on what you have to start with, or what else you plan to do to the engine. If you have low compression (9.5:1 or less) and are not going to change pistons or mill the heads to restore the cylinder pressure, save some money and go with the ported iron heads."

 

[blackhand]

Correct me if I am wrong, but aren't aluminum heads on a low compression motor a poor choice?? The thermal properties in effect lower the compression by reducing the heat.

I have no doubt that this is true, and to be honest I hadn't even considered it. I spent the whole morning thinking about this. It makes sense to me... it's not the compression per say that is reduced, it's the cylinder pressure during the power stroke, which torque and horsepower are 100% dependent on. If heat is dissipated more efficiently by aluminum heads, then chamber pressure will be reduced due to the lower temperatures. The question is, by how much?

In my case, I am replacing my old cheap Summit brand cam with a Hughes Whiplash cam, which is specifically designed to maximize dynamic compression, and therefor chamber pressure, on low-compression engines. I think that this cam alone will more than compensate for any loss due to increased thermal efficiency. Not to mention that the heads have a closed chamber and will increase the static compression ratio by about 0.7 points.

Still, all other factors equal, I would probably make more power with this combination of parts and a set of 915 heads ported to flow as well as the Stealth heads. But it makes no difference in the end because I only plan to run this setup for a year or two while I find another 400 block to build into a 470 stroker! When I finally get the bottom end done this thing will be about 10.5:1 and the engine would probably not be very happy with a set of 915s at that point.

Ain't bench racing fun?

 

[blackhand]

Its good to see another washington boy on here

Not to hijack my own thread, but Younggun, did I see your Dart at the Mopars Unlimited Spring Round up in Everett a couple of months ago?

 

[MTmopars]

I personally love the idea of a wicked 400. They never get any love.

 

[blackhand]

Update:

The adjustable checking pushrod and lifter were sent back to Hughes yesterday. I am very confident that the measurements are correct and I look forward to receiving a set of custom pushrods.

I really can't say how satisfying it is to know that these parts will fit together perfectly. I plan on running this engine up to 5,500 - 5,800 RPM. That's not particularly high but I've never really done the math until now and at that RPM the valves open 45 - 50 times per second! That's pretty amazing to me and it just underscores the need for quality valvetrain components that fit together perfectly.

 

[younggun2.0]

Not to hijack my own thread, but Younggun, did I see your Dart at the Mopars Unlimited Spring Round up in Everett a couple of months ago?

No. I just got my car running a few months ago. I live in Puyallup and with no glass in the car yet I stay local.

 

[RustyRatRod]

It is my understanding that the material of the head does not effect the compression rate at all. I believe that you are ABLE to get away with approx. 1 point more of compression with aluminum heads because they disipate heat faster and dont hold the heat like an iron head. when an iron head hold the heat it causes pre ignition or detonation.

correct me if im wrong. lol

I am not going to turn this into another aluminum VS iron head thread. I have been hammered for being "wrong" about it, so I am done with the argument. I am keeping my opinion on it to myself. If you want to discuss it through PM's I will be happy to.

 

[younggun2.0]

I am not going to turn this into another aluminum VS iron head thread. I have been hammered for being "wrong" about it, so I am done with the argument. I am keeping my opinion on it to myself. If you want to discuss it through PM's I will be happy to.

not that big a deal to me. I hate the pissing matches that go on too. I was just interested in the topic.

now lets see more pics of the 400 build.

 

[Abodybomber]

Nice detail work,subscribed.

 

[blackhand]

now lets see more pics of the 400 build.

Gladly:thumbup:

Here's a couple close-ups of the latest version of the Hughes rocker arms. There's a large groove machined into the top to direct oil down to the roller tip. The shafts have also evolved; the banana grooves are gone, replaced with what I would describe as a flat spot machined onto the bottom of the shaft where each rocker arm sits.

I am a little disappointed with their hold-down kit though. Each cylinder required six 0.030" spacers and four 0.015" spacers to get the rollers centered laterally over the valve tips. That's a total of eighty spacers for the whole engine! I really wish they had designed the hold-downs to be substantially wider so that not so many spacers are required. I have contacted them about this (thinking that maybe I was sent a set of small block hold-downs) but they insist that this is correct. But get this, the kit only comes with 50 spacers!! Yes, you have to order an extra set of spacers just to get these parts to work together even though they are designed for one another.

 

[younggun2.0]

One of these weekends you should come on down and bullshit and we can go for a ride in my rattle trap. Then you will know what to expect.

 

[william]

Gladly:thumbup:

Here's a couple close-ups of the latest version of the Hughes rocker arms. There's a large groove machined into the top to direct oil down to the roller tip. The shafts have also evolved; the banana grooves are gone, replaced with what I would describe as a flat spot machined onto the bottom of the shaft where each rocker arm sits.

I am a little disappointed with their hold-down kit though. Each cylinder required six 0.030" spacers and four 0.015" spacers to get the rollers centered laterally over the valve tips. That's a total of eighty spacers for the whole engine! I really wish they had designed the hold-downs to be substantially wider so that not so many spacers are required. I have contacted them about this (thinking that maybe I was sent a set of small block hold-downs) but they insist that this is correct. But get this, the kit only comes with 50 spacers!! Yes, you have to order an extra set of spacers just to get these parts to work together even though they are designed for one another.

I had the opposite problem with mine I had to grind the hold down to get enough clearance. I was running ez heads old style hughes with 1.6 rockers