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-   -   400 Engine Build (https://forums.maxperformanceinc.com/forums/showthread.php?t=776139)

Cliff R 06-26-2015 10:40 AM

400 Engine Build
 
Moving along nicely with our 400 (412cid) engine build. I'll be putting some pics up over the next few days.

The engine has Eagle rods, Icon Flat tops, std/std "N" crank, and topped with #46 heads from a 1969 428. Compression ratio is 10.65 to 1, and will be tuned for and run on pump gas only.

The heads are well prepared, screw in studs and 2.11/1.77 valves, around 240 cfm. We're using a "coated" (Ion-Bond) Crower 60919 cam, ICL at 108.5, and Rhoads V-Max lifters and Harland Sharp 1.65 rocker arms.

It's going into my Ventura for run-in and a couple track outings, then headed for a 67 GTO 4 speed car with 4.30 gears. Should be quite a ride!......Cliff

77 TRASHCAN 06-26-2015 10:52 AM

Alrighty!!!
Been waiting on this one, for a while!!!

locomotivebreath 06-26-2015 10:59 AM

U guys going to run headers ?

Skip Fix 06-26-2015 12:23 PM

Cliff when I swapped the 400 in my car in place of a 455 it felt like a dog until it got more convertor and more gear. So your butt meter will feel down without the bottom end grunt.

Sounds like a good stick car motor.

t money 06-26-2015 12:28 PM

I look forward to read about this engine. Can I ask what intake and carb or is that a dum question

Motor Daddy 06-26-2015 12:29 PM

Quote:

Originally Posted by Cliff R (Post 5423756)
Moving along nicely with our 400 (412cid) engine build. I'll be putting some pics up over the next few days.

The engine has Eagle rods, Icon Flat tops, std/std "N" crank, and topped with #46 heads from a 1969 428. Compression ratio is 10.65 to 1, and will be tuned for and run on pump gas only.

The heads are well prepared, screw in studs and 2.11/1.77 valves, around 240 cfm. We're using a "coated" (Ion-Bond) Crower 60919 cam, ICL at 108.5, and Rhoads V-Max lifters and Harland Sharp 1.65 rocker arms.

It's going into my Ventura for run-in and a couple track outings, then headed for a 67 GTO 4 speed car with 4.30 gears. Should be quite a ride!......Cliff

It better run faster than 110.68 in the 1/4 at 3860 lbs race weight! It better! ;)

http://i1281.photobucket.com/albums/...ps70df9497.jpg

Skip Fix 06-26-2015 12:53 PM

"It better run faster than 110.68 in the 1/4 at 3860 lbs race weight! It better! "

That will be a good task for a 400 that has a fairly mild cam.

Cliff R 06-26-2015 12:56 PM

My car isn't set up well for this sort of power, but it should run into the 12's without much effort. We'll get some track numbers on it sometime next month.

The engine is being built specifically for the manual transmission/4.30 gear ratio deal, so will fair a lot better in that application than in my car with a tight 10" converter and 3.42 gears. As Skip mentioned, it will probably "feel" like a dog compared to the 455 it's replacing, which will only get me motivated more to get the 455 back in place.

I would add that there really isn't anything wrong with the 455, still holds 60psi hot over 2500rpms, and 25-30psi at idle, not using much oil, and making same power as it did when installed.

I want to do a couple of things to it, which include new rod bearings, timing set, and check things out. Also going to replace the PRW rockers with Crower Enduro's, and a new set of valve springs for sure. It's been on pump gas for quite a few years at 11 to 1 compression, so I'm curious to see how the internals are holding up?.......Cliff

Motor Daddy 06-26-2015 01:00 PM

Quote:

Originally Posted by Skip Fix (Post 5423808)
That will be a good task for a 400 that has a fairly mild cam.

If the heads flow 240 that is 1 more CFM than mine flowed. ;)

Motor Daddy 06-26-2015 01:05 PM

Quote:

Originally Posted by Cliff R (Post 5423809)
My car isn't set up well for this sort of power, but it should run into the 12's without much effort. We'll get some track numbers on it sometime next month.Cliff

Your car is set up to put the power to the pavement very efficiently. Looking forward to the first run's time slip. :)

68azbird 06-26-2015 01:28 PM

1 Attachment(s)
400 with Unported heads around 10:1 compression factory HFT.

77 TRASHCAN 06-26-2015 01:53 PM

It'll definitely be an attention getter at the local Dairy Queen :)

Cliff's 3.42 gear may not be enough for that 400.
Looking forward to seeing how it does in HIS car w/ 3.42 gear and automatic, drive-abilty wise, and performance wise...

Motor Daddy 06-26-2015 01:56 PM

I had the 3.42 too!! Like I said, it better!! :) :)

Cliff R 06-26-2015 02:08 PM

This engine will run well and drive fine in my car, because we have 10.65 to 1 compression in the engine, and Rhoads lifters. This will make for a nice idle quality, and plenty of low end power, with the "real" power coming in just about where my converter stalls at.

With the 3.42's it will have it's tongue hanging out a bit thru the 60', but pull like gangbusters on the rest of the run. It takes 450hp for my car to run 12.0's, 494hp for 11.60's, 514hp for 11.50's, and 550hp to go low 11's.

This engine should make a little over 1hp/cid, so it's got enough for some 12 second runs if the moon, stars and everything else line up right for us!.....Cliff

Motor Daddy 06-26-2015 02:16 PM

Quote:

Originally Posted by Cliff R (Post 5423837)
This engine will run well and drive fine in my car, because we have 10.65 to 1 compression in the engine, and Rhoads lifters. This will make for a nice idle quality, and plenty of low end power, with the "real" power coming in just about where my converter stalls at.

With the 3.42's it will have it's tongue hanging out a bit thru the 60', but pull like gangbusters on the rest of the run. It takes 450hp for my car to run 12.0's, 494hp for 11.60's, 514hp for 11.50's, and 550hp to go low 11's.

This engine should make a little over 1hp/cid, so it's got enough for some 12 second runs if the moon, stars and everything else line up right for us!.....Cliff

Lots of compression too! Way more than my 9.33 weak lunged little 400 had (all cast.) :)

Motor Daddy 06-26-2015 02:18 PM

...but that 041 probably likes more, right? Like every other engine likes more compression?

Motor Daddy 06-26-2015 02:20 PM

...and those cast pistons looked like they were at the bottom of a well in that cylinder at TDC... Not like yours that sit at the top of the well, eh? :)

Motor Daddy 06-26-2015 03:46 PM

Mine was a Crower cam too!! 60... sump'n or nuther..., just like you're's, Cliff!! :D

Skip Fix 06-26-2015 03:56 PM

68azbird weight? Which factory cam?

Not too many factory non ported head factory cam cars ran or run 12.00s @110 especially weighing in 3800-3900. Making 450 HP for Cliffs car(I'll bet a little lighter than 3850lbs) to run 12s not too many 400cis making 400-450hp on a conservative dyno or mph to go with it,especially with stock heads and a factory stock cam, unless we are talking NHRA "stock" cam or even NHRA Stock "non ported heads"). Heck the RAIV motors were rated at 370 HP, gross HP no accessories and they flowed better than D port heads and had the biggest factory cam.

Racing the NMCAs stock classes from Dallas to Atlanta for 4 years and lots of PSN events I sure did not see them. Steve Coombs car was in a different class than mine and a click faster with his 400 but not sure he was even 12.00s back then maybe he'll chime in.

Cliff R 06-26-2015 03:56 PM

MD, the rule of thumb for compression vs cam choice is one full point for every 10 degrees. So if I build a 400 at 9.5 to 1 compression that's got a cam in it around 220 intake/230 exhaust (for example), that makes it really happy everyplace, I need to go up about 10 degrees with the same engine if I build it at 10.5 to 1 compression.

This will create about the same dynamic compression, vacuum at idle speed, and off idle power/street manners. Low speed power will be close between those engines, however, the higher compression engine with the bigger cam will start leaving the lower compression engine in the dust out about 3500rpm's or so, and absolutely KILL it in upper mid-range and top end power, extending the power and shift points by at least 500rpms, if not a bit more if I've topped the engine with really good flowing heads. To sort of see how that deal works, take a look at the thread I started on cams for 455 builds and compare the dyno charts between the two roller cams used in that build. The same logic applies here, but in this case we're using higher compression with a pretty "hefty" camshaft.

What folks fail to realize with these things, is that octane requirements are pretty equal between the two engine examples mentioned above, and past peak torque, or max VE, the events simply happen too quickly to see enough rise in dynamic compression to require any additional octane. So our higher compression 400 build here will not be any more octane sensitive than a 9.5 to 1 400 build with a smaller cam in it.

I'm probably being a bit conservative with my power rating on this engine. That last 400 I dyno'd with untouched big valve heads at 10 to 1 compression made 424hp/465tq with a smaller 228/234/112LSA cam, and a 400 with unported KRE heads and this same cam will make 450hp without breaking a sweat......Cliff


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