451 build questions

[AV1972SSP]

Ive been lurking on the boards for a while now and thought Id make a post about my winter project. Building a 451 for my 72 SSP. Im definately on a budget so keep that in mind when you see my component choices. Heres what im thinking

- 72 400 block .040 over
- Forged 440 crank and rods
- KB-280 pistons, zero deck, set for .040 quench
- 346 heads 86-88cc chamber, flow 250-260@ .600
- Lunati 60343 solid cam, 259/267 @ .050, .585/.600 lift
- 440 source 1.5 roller rockers
- M1 single plane intake
- 850 dp carb

Car will have 727 with 9.5 dynamic converter, 8 3/4 sure grip 4.10 gears, and probably a 275/60/15 drag radial.

I would like to get an honest 500HP and put my SSP in the mid to low 11's. My biggest concern is the cam was originally going to go with a mp 557 cam kind of like 383mans old 440, but i was also looking at the mp590. I think the lunati kind of splits the difference and its a more modern grind. Compression would be over 11:1 so i would run 93/110 mix, probably about 60/40 ratio. Im lucky that 3 stations within a couple miles have 110. let me know what you think. thanks

 

[Sweet5ltr]

Ive been lurking on the boards for a while now and thought Id make a post about my winter project. Building a 451 for my 72 SSP. Im definately on a budget so keep that in mind when you see my component choices. Heres what im thinking

- 72 400 block .040 over
- Forged 440 crank and rods
- KB-280 pistons, zero deck, set for .040 quench
- 346 heads 86-88cc chamber, flow 250-260@ .600
- Lunati 60343 solid cam, 259/267 @ .050, .585/.600 lift
- 440 source 1.5 roller rockers
- M1 single plane intake
- 850 dp carb

Car will have 727 with 9.5 dynamic converter, 8 3/4 sure grip 4.10 gears, and probably a 275/60/15 drag radial.

I would like to get an honest 500HP and put my SSP in the mid to low 11's. My biggest concern is the cam was originally going to go with a mp 557 cam kind of like 383mans old 440, but i was also looking at the mp590. I think the lunati kind of splits the difference and its a more modern grind. Compression would be over 11:1 so i would run 93/110 mix, probably about 60/40 ratio. Im lucky that 3 stations within a couple miles have 110. let me know what you think. thanks

E85 would be my choice. 110 gets mighty expensive, and with 11:1 you'll be using it often. The .590MP is a completely different animal, the mopar grinds have 'slow' ramp rates in comparison to the modern grinds. If you want reliability and performance, they are the ticket. Ditch those roller rockers, get yourself a mint set of Ductile Irons if you want a rocker that will last. Cheap rockers and high rate, high lift camshafts don't mix.

 

[IQ52]

I like it, I like it a whole bunch. I don't get it though, why do you say it would be over 11:1? You using a .020 head gasket? Seems to me it's very near a straight pump gas engine. So mixing a little 110 if you can get it, not a bad idea.

 

[bigblock]

Put on some Ed or 440 Source alum heads. BTW you will have a 456 CID if bored .040. 500 HP is no problem so the cam does NOT have to be radical.

 

[Redhorse719]

I like it, put it together you can make upgrades as the cash flow improves. X2 on the rockers. Oh, welcome to FBBO.

 

[AV1972SSP]

E-85 might be an option if need be. what ET are you running with your combo Sweet5ltr ?

I like it, I like it a whole bunch. I don't get it though, why do you say it would be over 11:1? You using a .020 head gasket? Seems to me it's very near a straight pump gas engine. So mixing a little 110 if you can get it, not a bad idea.

No. felpro .039, pistons have 4.4cc? quench pad. piston at zero deck. If its less and runs on straight 93 wont bother me a bit.

 

[Budnicks]

Cylinder heads are probably the most important part, wedge heads are not that good from the factory, probably the biggest choke point of the build, you need a good set of professionally ported heads, with a properly matched set of valves/seats, performance valve job, valve springs, retainers, locks & seal, properly assembled... good luck sounds like a decent start... a heavy car, needs good power, to run deep into the 11's.... I would suggest lightening the car where ever possible... IQ52 knows his stuff, he could hook you up...

 

[IQ52]

E-85 might be an option if need be. what ET are you running with your combo Sweet5ltr ?



No. felpro .039, pistons have 4.4cc? quench pad. piston at zero deck. If its less and runs on straight 93 wont bother me a bit.

Sure it has a quench pad but it also has valve relief pockets, effectively giving you a 0cc piston. Says so right in the catalog, KB280 0cc. Now KB 251 is -4.4cc

You said you're using the 440 rods, so use the 0cc KB280, 400 rods use the KB251.

 

[AV1972SSP]

Sure it has a quench pad but it also has valve relief pockets, effectively giving you a 0cc piston. Says so right in the catalog, KB280 0cc. Now KB 251 is -4.4cc

You said you're using the 440 rods, so use the 0cc KB280, 400 rods use the KB251.

OK now i see lol I was looking at the kb251 info. kb-280 says 10.4 with 88cc. Ill definatley be one the lookout for a set of iron rockers. Better heads will come down the road. My 346's still have decent valves and guides and it wont be my first rodeo with a grinder, shouldnt be hard to get 250cfm out of them. I shouldn't have more than a couple hundred into them. I really appreciate the input guys!

 

[747mopar]

I like it but then again I just built one for my car so I'm a little partial. I also used the KB pistons but in a milder build (501" lift) with ported 452 heads "snappy motor".