400 Small Block Build. 500+ HP

[Winston Wolf]

I decided to take some pictures while I do a head and cam swap on my 400. Hopefully this will help some of the guys with less experience gain a bit of insight.

 

This could possibly be done with the engine in the car, but I also needed to do some work on my transmission pump and torque converter, so it is easiest to pull the engine in my situation.

 

I don't have a lift, so it's up on the jack stands for me....

 

 

 

Starting disassembly, remove shroud, fan, etc, unhook everything.

 

 

Engine teardown. Trick Twisted Wedge heads and Performer RPM intake off. Pistons exposed.

 

 

This engine was gone through last year, .040 over Mahle piston kit connected to 6" Eagle Rods and a forged Eagle Crank. I really like the Mahle stuff, as the pistons are light and uses tight rings. You can pick up 7-10 HP using these pistons. I didn't need to do anything with the pistons/crank at this time, so it makes for a fairly quick update.

 

The cam was removed and the new cam installed. The new cam is a solid roller Lunati model. My cam is a standard base circle, so I needed to pay special attention to cam/rod clearance. If there had been interference, I would have needed to change to a small base circle cam, which is usually a special order item. Fortunately I didn't have any issues with the Eagle rods.

 

Here is the cam in, timing chain on and cover.

 

 

Degreeing a camshaft is a must for any performance setup.

I found that the cam was off by 4-1/2 degrees (retarded) when installed with the dots aligned.

 

 

I changed out from a gear drive to a chain drive, mostly because of 2 things. The old Pete Jackson drive I had in the car has bushings for changing the cam timing. I must have lost the bushings and they pretty much can't be found anymore, this would limit me to only 1 position for cam timing. Probably not an option. 2ndly, I wanted something that would allow me to change the cam timing without engine disassembly. In come Cloyes with their Hex-Adjust roller timing set and the Quick Button cover. Could I have used the Pete Jackson gear setup with my new roller cam? Yes, it has a cam button (which is needed for any roller cam), but I was nervous using the stock cover, as the stamped steel is a bit too flexible for my liking. Plus the Cloyes uses a bearing against the block instead of a bushing, which I like. A flat tappet cam holds cam into the engine because of a taper cut into the lobes. Not the case on a roller. That is why you need a cam button. This cover has the button built in and it is adjustable from the outside. With a standard cover, you need to install and uninstall the cover to check the clearances, somewhat of a pain.

 

 

Here are the heads, notice the 400 steam holes that had to be drilled...

 

 

Checking the valve to piston clearance. To do this you place some playdough or clay ontop of the piston, install the heads (cam must be degreed in first), lifters, pushrods, and rockers. Set them to zero lash. Always use a solid lifter to check this, as the hydraulics will compress as you turn over the engine. Mine is solid to begin with, so not worries for me.

 

 

The valves make indentations in the clay, which you can then measure to get your clearance. I usually do this without the head gasket on. My gasket has a .038 compressed thickness, so I can just add this in. With the 2.08/1.60 valves and .600 lift cam, I had plenty of clearance using these Mahle -5cc relief pistons.

 

 

Here is a shot of the crank scraper. It is used to "scrape" the oil off the crankshaft as it spins around. This can add a few HP.

 

 

Heads on and torqued down. Next step is to check for proper pushrod length. I ended up with 8.050 pushrods. These had to be ordered, so I will be at a stopping point for a couple days. That's ok, as it gives me time to do the transmission mods and get some of the pullys and brakets cleaned up with a fresh coat of paint.

 

 

More to come.....

 

 

[Winston Wolf]

Here is a shot of the crank scraper. It is used to "scrape" the oil off the crankshaft as it spins around. This can add a few HP.

 

 

Heads on and torqued down. Next step is to check for proper pushrod length. I ended up with 8.050 pushrods. These had to be ordered, so I will be at a stopping point for a couple days. That's ok, as it gives me time to do the transmission mods and get some of the pullys and brakets cleaned up with a fresh coat of paint.

 

 

More to come.....

[Ian]

Looking good! I would love to get a set of Aluminum heads

[72MC]

Interested to know what rocker arms(ratio, full roller, etc) and type of lifter(roller, flat tappet, retro fitted, etc) you're using in order to use a 8.05 push rods.

 

By the way, looks good. Have built three engines myself and have throughly enjoy the builds. Thanks - Dave

[TN454Monte]

Great looking set of pictures, thanks!

[Winston Wolf]

Interested to know what rocker arms(ratio, full roller, etc) and type of lifter(roller, flat tappet, retro fitted, etc) you're using in order to use a 8.05 push rods.

 

By the way, looks good. Have built three engines myself and have throughly enjoy the builds. Thanks - Dave

 

I am using retrofit solid rollers, Lunati pn 72403

Comp cams Ultra Pro Magnum 1.52 roller rockers, pn 1604-16

 

I think the odd pushrod length is from 2 factors: block was decked, but not to zero. Valves are a bit longer than normal, AFR uses either +.050 or +.100, I don't remember. But the installed height of the springs is 1.950" with the big 1.59" diam for the solid roller.

 

I use an adjustable pushrod to check the length, pattern is dead nuts centered with a nice pattern on the valve.

[72MC]

Thanks for the info Winston. I have a couple of those adjustable pushrod checkers. They are a nice tool.

 

The reason I asked was my setup is Jegs/Canfield aluminum heads with 1.52 Comp pro magnum full roller rockers and Comp retrofit roller hydraulic lifters and my pushrod length was 7.300, which is less than the 7.800 stock length. This surprised me at the time but the geometry doesn't lie.

[Winston Wolf]

Well, Back at it tonight...

 

Here is my fuel pushrod. Brass tipped because of the billet camshaft. I am also going to run a special Lunati gear on my distributor.

 

 

Fresh coat of ceramic paint on the headers.

 

 

Here's how to double check valvetrain geometry. First mark the valve tip with a sharpie

 

 

Install lifters, pushrods, and rocker arms. Adjust to zero lash, then rotate the engine.

 

 

Then you can see the witness marks on the valves. Note how they are centered on the valve tip. I would have liked a little tighter pattern (narrower) but this is as good as it gets with my setup. Still, perfectly acceptable.

 

 

Below you can see how to adjust the valves. This cam calls for a .016 lash setting hot. Since I am setting these cold for innitial startup, I set them at .012" which should be just about right. I will readjust them hot once the engine is back in the car.

 

 

High flow thermostat, 160 deg is what I like to run in a 400 SBC. This one also has bypass holes so there is alway some coolant able to flow.

 

 

Here you can see the new Edelbrock high volume water pump. Engine is masked and ready for paint.

 

 

Painted up. I like the sleeper look, so I painted everything to look stock. Should be ready to pop back into the car Friday night.

 

[Winston Wolf]

Also, Here is a picture of why I needed to pull the pump out of the transmission. I am using a lockup converter with heavy duty clutches so I can lock at full throttle. The lockup works by dumping pressure that engages the clutch. The tube I drilled and added connects the port that is drained to the inlet of the pump. This will allow a suction to evacuate the oil quickly and give me rapid lockup once I hit the switch. I also removed the check valve from the input shift to help a harder clutch engagement.

 

[Monte7071]

Looking good nice work.

[wallaby]

I love working out all that detail stuff. It sure is looking good.

My only comment is about the initial valve adjustment. A cold lash should be larger than the hot lash. When things get hot they expand and the clearances will reduce. You said you were going to re-adjust them later, so no big deal. it's close enough to get her running!

Press on! I'm excited for you.

[Winston Wolf]

I love working out all that detail stuff. It sure is looking good.

My only comment is about the initial valve adjustment. A cold lash should be larger than the hot lash. When things get hot they expand and the clearances will reduce. You said you were going to re-adjust them later, so no big deal. it's close enough to get her running!

Press on! I'm excited for you.

 

Thanks for the comment, you are partially right on the lash. One thing people often overlook is the fact that aluminum expands at a rate greater than iron. With this aluminum headed engine, the heads will expand more than the pushrods and rest of the valvetrain. This increases the distance from rocker tip to cam lobe more than in an all iron setup (when hot)To adjust for this you need to subtract from the hot lash setting when setting them cold. All this is out the window with Hydraulic Lifters of course.

 

Here are a couple pages that explain it better than I can.....

 

Cold Lash on Speedtalk Crane Cams Lash Setting.

[Donny vestal]

Looking good nice work.

i just rebuilt my 400 a couple weeks ago with a rebuilt 350 turbo all stock.what year is that 400.i see its got 3 freeze plugs.

[Winston Wolf]

Thats a G 10 70 block.

 

July 10th, 1970...... Not too many of these 4 bolts beauties left.

[jpnewlin]

Sounds like you know your stuff.

Its looking good.

[Winston Wolf]

Engine is back in. Installed a .035 thicker flywheel from Huges. I was getting some very slight rounding of the torque converter mounting holes in the stock flywheel. This engine uses a 350 balancer and flywheel. I don't really care for the external balancing of factory 400's, so when I put in the steel crank years back, I used an internally balanced one. (along with a Fluidamper balancer as you can see)

 

Had to do some modifying of the trans pan. With the new lock up tube I now need to run a AC Delco filter for a 700-R4. The cheap chinese ones you get at Autozone or Oreily will actually cavitate when you get into the big HP stuff. Problem is that the filter uses a bigger neck and is alot thicker. I needed to grind off the posts in my Huges deep pan and use a different oring setup to seal in the filter. That slowed tonights progress a bit.

 

[Ian]

Looks good in there!

[Winston Wolf]

Here is a shot of the new converter and thicker flywheel

 

 

 

A different material for the distributor gear is needed with some of the roller cams. This is called "Everwear", basically a nitrided gear so it doesn't wear out on the billet steel camshaft. You can also see the Mallory breakerless iginition I run. I like things to look stock, this is the original distributor that I have modified. You can see the carboning of the rotor, I replaced both the rotor and cap.

 

 

 

Here we are right before initial startup.

 

 

After a small break in run time, and adjusting the timing, all seems well. With a roller cam you don't really need to break them in like a flat tappet. It sounded like I may have already blown a header gasket, so today I will swap that out and hot set the valves. I did notice that it now pulls much more vacuum at idle, 12" at 1000 vs 9-10 with the flat cam. It does seem to idle smoother also, with the old 292 magnum cam it would shutter and lope like a race car.

 

I have dyno time scheduled for Thursday, so I will be able to overlay old vs new and see just what kind of results my efforts were worth......

 

[Winston Wolf]

Took the car out and put some miles on it. It does have more power. I can't stop the tires from spinning until 3rd gear now. (I'm talking going 30 in 2nd and flooring it and it spins; not from a dead stop) Sounds pretty mean while driving the car. Looks like my B&M lock up unit burned out though. I'll have to get a new one of those.... The new converter lockup is like a 5th gear. It hits hard just like a shift when it engages. Jetting looks to be pretty good, about what it was with the other setup. Seems to be leaking oil out the rear of the pan. I decided to try a 1 pc rubber gasket, I guess it didn't work like I had hoped...

 

Here is a video of it running.

 

[BAMC1369]

I have a 72 400sbc engine code 330817. If i ship you my stock engine about how much would you charge me do do every thing you just did?

 

 

[Winston Wolf]

I have a 72 400sbc engine code 330817. If i ship you my stock engine about how much would you charge me do do every thing you just did?

 

 

pm'd

[TN454Monte]

Nice work, the car sounds great!

[Winston Wolf]

Well, made it into the dyno today. Looks like I have some more work to do... Here's a couple pics of the car, then I'll get into the results.

 

 

 

 

First run was horrible. I have no idea what is going on. Here it is against a run last year. Made MUCH LESS.

RunFile 003 is from last year, RunFile 001 is today

 

I was shocked to say the least. Checked timing, 34 deg, jetting was dead nuts. No idea what the issue is. Next run we locked the converter in 3rd. Then 3rd run it was locked and I leaned it out one stage. See below.

 

 

As you guys know I did change out my converter from the Bowtieoverdrives 2400 stall to the Precision Industries 3500 stall. Last year I did not lock the converter during pulls. I think there may be an issue with my converter????

 

Here is a comparison to last year's setup vs the new heads, cam, carb and converter. I was expecting a lot more and am a bit disappointed at how the power curve still drops off after 6300, even with this solid roller cam.

 

 

We had to cut the runs short today. I blew the themostat gasket and it was spraying water on the last run. See vid below

 

 

 

 

I'm looking to you guys for any suggestions and opinions. I'm stumped at this point.

 

 

[Jared Richey]

Take it back to the track and see what it does now. I got to say I'm stumped also as for as the dyno results.

 

 

[wallaby]

It took me a while, but I can follow it. The last graph shows it pretty nice. It looks like you gained about 20 hp across the board; the two hp curves are almost identical with one being just a bit higher on the scale.

The Torque is doing a similar pattern; just about the same as before but about 25 lbft better across the board. The big difference is you gained a BUNCH of torque around 4000 and below. It looks like nearly 100 lbft! That's a difference you can feel in the seat of your pants for sure.

I expect the roller cam is giving you the better bottom end torque with it's quicker valve openings.