408 stroker build sheets

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DJVCUDA said:
I'm in the middle of building a small block stroker - I have a stock set of Eddy heads I was going to put on there -

The short story is that the guides needed to be resized, the intake valves needed to be re-ground ( 4 were out of round by over 1.5 thou) and the exhaust were a little better.

THere was also shavings abound in the water passages.

Could I have bolted them on? Yes

will it run better now that I spent 150 bux to have them gone through? YES!
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It might keep on running also. All it takes is 1 valve to stick open and not close fast and then the piston strikes it and kaboom, there goes the engine. Never just bolt on a set of Eddy heads out of the box, never. If you drive the car long and hard enough something bad is likely to happen.

Engine builders know all about those sticking valve guilds, its not the 7,000 rpm that did the engine in, more likely it was a valve guild that was too tight and the valve hung open a faction of a second too long
 
There is always some junk in the water passages, never can get them 100% clean. An old trick was to use shaving cream, in each water opening you shoot some shaving cream in just before bolting the heads on, this way no dust/dirt wil fall out while placing the head on for the last time. Shaving cream just fades away in the cooling system once you fill the rad.
 
They pretty much covered it... You don not use lift range or seat pressure to determine a valve spring's compatibility. You use the pressure/inch and the installed height, among other things. No mass produced head (and some not-mass produced..) will have average valve job quality. I want to make sure I am on the top end of quality, not the ones that blow the curve, so to speak. Guides are tight, seats are out of round, valves themselves are out of round... It's a fact of life. As for the cam... Hydraulics are fine, but the fast rate of lift ones need a lot of spring, and generally can't pull the same rpms. A solid flat tappet, assembled properly, will not need any more than seasonal checking and will make more torque, more horsepower, and maintain both over a flatter power curve, than any hydraulic. So for a street car, and someone who has the knowledge and initiative to do the basic maintenance, the solid is the way to go every time. Also bear in mind, the heads should be assembled with the outer springs only when they are corrected... The inners will need to be installed when the heads are hot-re-torqued and after the cam is broken in.
 
the converter is pretty wicked as it is, so im good there. 4000 flash, footbraking to 3000. I'll probably get the heads gone through while the block work is being done. im gonna raid junkyards this weekend and see what 360's they have to offer. i have a buddy with a 73 360 block also that i might grab. I just want this one to do what the crate junker should have done. exactly why i dont mind an aggressive cam, all i have to do it limp it 6 miles to the track and home. it already ran 12.00's so i know its capable, just need to start building it!
 
i suppose i will.lol...adding $$$ to this build every day...good thing i get my parts at cost
 
Guitar Jones said:
All of the performance aluminum heads need work to perform to their potential.
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I'll second that. My edelbrock heads had significant runout in the seats, so I got a Hughes 5 angle valve job on them, and back cut the valves.

I ported them myself, following the recipe Steve Dulcich laid out over several MP and Car Craft articles. Pushrod pinch and exhaust port size are the major restrictions. A 408 has 48+ more cubes than what these heads were designed for.

I use a Hughes 218/228/112 0.565"/0.565" hydraulic roller cam, comp 918 beehive springs, Hughes 1.6:1 rockers. Eagle crank & I-beam rods. KB pistons. Total Seal rings. Performer RPM airgap intake.

I was hoping for 450hp/500ftlb at the crank. I was inspired by a series of torque monster 400cid builds in the magazines a few years ago. I ran 12.70's @ 107 with 727 trans and 2.76 gears. pretty torquey motor.
 
LXguy said:
Put 360 parts on a 408 and you'll run 360 ETs.


Everybody likes to choke their strokers with parts intended for much smaller engines and ends up running numbers they could have gotten from a ring and bearing rebuild on a 340/360.
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There is a world of truth in these two comments :prayer: - and I'm guilty of doing both.

Dyno2000 shows a 75 HP improvement using ported Eddie heads (285cfm peak) over my ported cast 587s.(245 cm peak)
 
johnnymac2k6 said:
Anyone want to give up a 408/410 parts list? something that has worked very well and put down some nice numbers.

i was running a crate 408 that made 380HP and 460 Ft lbs.... i always considered this to be fairly low, but my car being set up with a great converter it still ran 12.00's. the cam was very mild in my opinion only being the 484 lift purple cam. long story short it was a complete nightmare since day one, and it went back for a full refund....
so anyways...here's my plan as of now.

edelbrock aluminum heads (already better than the iron magnums my old one had)
rpm airgap intake.
408 forged rotating assy
http://www.summitracing.com/search/...onnecting-Rod-Beam-Style/I-beam/?Ns=Price|Asc
going with a roller rocker setup though.
one of these..750 double pumper that i may have to upgrade to an 800 kit.

and im open to cam suggestions. im currently looking at a comp hydraulic cam
http://www.summitracing.com/parts/CCA-CL20-229-4/
my converter can footbrake up to 3000, flashes at 4..those numbers look perfect for me. my last junker liked to shift at 5500...im hoping to get more RPM out of this one.
i've built engines before and since the drop in and go engine was a failure im doing it right this time...myself

anyways how much better can i look to do than the previous 380/470 with this setup. 450hp/500ft lbs too much to shoot for?
basically want a race engine that i can drive 6 miles to the track and back home, and still run in the 11's..if not the tens. CR around 10.0 for pump gas

let me know what you guys think!
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This is the exact reason we did this article! http://www.carcraft.com/techarticles/ccrp_1006_small_block_mopar_stroker_dyno_test/index.html

And this same engine with a 950HP carb made 500HP. Then with the same combo, just changing the cam to a solid FT (251-260 on a 108lca) and porting the pushrod pinch area of the heads made 521HP and 527TQ.

Plus we have done a hyd. roller version for Cannucky on here that made 519HP at 5400rpm! TQ was 520's also.

Brian
 
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