Since I just purchased a set of these heads and intake to top our New R3 block, I was wondering just how much Naturally Aspirated power that people are really making with these? I know what they are capable of, but how much power or what is the most N/A power you guys have seen? Ours will be 4.155 bore with 3.79 stroke with 12.5-13:1 compression and an unknown cam so far. Solid roller however. Just curious.

Ryan will have some dyno numbers in a few more days. iam sure it's going to make good power how big are your heads? cnc?

hope this helps web page

Our heads are just as cast heads. Our cylinder head guy wanted them that way to start. It will be interesting to see how much power we can get out of this 411" engine. My buddy over at CP is goign to make the pistons for me. Brian at IMM has already built a 408" 360-2 CNC headed engine for a guy in Washington and it made almost 690 hp if Im not mistaken;.. on his DTS Dyno.

it was only 685 hp @7200 rpm, but i'll be happy to fudge and call it 690 . motor and trans are sitting in the car. hoping i can get it done for vegas.i'd post pics but i can't figure out how to make the pics fit

We have run 10.30@131+ at a little under 3500lbs 9" tyre, with 258@.050", 11.7:1 & 4150 carb
I think over 700 is achievable, with a well scienced build

I've only dynoed one -1 motor, it's #'s are attached. That was 451", 4.185"X4.10", 12.5:1, roller in mid 270's, 950HP, ICH manifold, 1 3/4 to 1 7/8 step headers. Had INDY's basic 245 non raised port CNC heads with just a valve job. 2.10"/1.65 valves. Keep in mind my old 428" 11:1 motor with W8 heads, Dominator & 280 @ .050" roller made 676HP on same dyno for some sort of power comparison dyno to dyno.

I'll be dynoing a very basic 416 next Monday with a set of 245's & Gilbertos should also be on dyno right after Christmas.

The 416 is 4.07" X 4.0", R3, SCAT 4340 crank, Eagle H's, Off shelf Ross dome pistons. 12.8:1... Cam is in 276/280 range .712"/.692"... ICH manifold, 1000 Race Demon converted to E85. This motor has the INDY Raised Port 245 CNC head with 2.15"/1.625" valves. No hand work, just our valve job & blending seats into chambers/bowls. I'll post #'s off of it Monday night if all goes well. Gonna try the 1000 Demon on E85 against a 1050 Quickfuel on Race gas, also going to try 3 sets of headers, a set of TTI's, a set of Custom TTI copies with smaller tubes, & my 2" W9 dyno headers.... Should give some interesting results, & will be first 245RP heads I've ran.

Gilberto's motor is much more "exotic" 449", 4.10" bore X 4.25" stroke X block. Alum rods, 14.2:1 Custom Diamonds, gas ports, .043 rings, vacuum pump, kicked out custom 12 QT oil pan, external oil pump, belt drive, Custom W2 T&D's, Big roller in the 280/288 range around .740", ICH manifold converted to 4500 flange... 1050 Dominator on race gas... His heads are 245 Raised Port CNC's with as much hand mods as I could do, almost 3" of cross section, 260 CC runners. 2.15"/1.60" valves.... heads flow 365 on my bench... Will be running it with my W9 dyno headers only. I dunno what it will make, but there's not too many more exotic INDY SB motors than that one running around out there. Pretty much no expense spared on that one, Aluminum hub ATI damper, Crank trigger, Weber belt drive, Stock Car products oil pump, custom Jeff Johnston ball bearing oil pan etc etc. Only things I could do to make it more radical would have been to use a siamese block with more bore size, pump bit more compression in it & maybe hair more cam. Short of doing a sheetemetal manifold etc..... But it "should" put up some big #'s. His Valiant being only 2500 lbs, it should go in the 8's pretty handily.

I prefer the 230 CNC Ovals for most motors under 420 inches, like the one Brian did (it has 230's on it, not -1's) They seem to work real well on the smaller CID stuff. That's why I'll be curious to see how the big RP head works on this basic 416 next Monday. (motor came to me assembled by another shop in NY with 7 dyno pulls on it & it was junk, so I did'nt pick the heads for it, otherwise it would have had Ovals on it)

My 408 with hand ported -1's made 530 at the tires and ran 6.30's @ 107 in a 3250 lb dart on motor. I also have a 418" pump gas motor with mildly hand ported -1's in a 3390lb Scamp and it went a best so far of a 6.55 @ 103 1/8th and a 10.37 @ 128 1/4 on that same pass. Motor is around 9.5 to 1 and runs on pump 93. It made 485 at the tires on a dynojet on motor. I have since gone to a set of 245 cnc raised ports I got from Ryan J for my 408. Im gonna dyno it once I get it back together and see if it makes any more power. Its now a 410" motor which is a little small for those heads but I have 2 systems on this car and run in a heads up class and its a pretty max effort type car. True stock suspension with 28x10.5s (motor is in a 86 mustang coupe with a glide) Ive been 5.50 @ 127 on a 225 (first stage) and just by bumping the 2nd kit went 132mph in the 1/8th. Car weighs 2950 with me in it and should go some 5.20's now on the sauce. Ran 6.19 @ 111 on motor before. Hoping for 5.90's now. We'll see.

I'm currently building my first all out race small block. 360-2 cnc ported heads, custom Bullet cam, Indy single plane, Quickfuel 850. Just ordered some stuff from Dram for a rotating assembly. 4.10 bore pistons (flat top) Diamonds, K1 light weight rods, and K1 4.00" crank. The compression will be lower than I initially wanted but it should still run hard at 2800lbs. Also just got my Hedman 1 7/8 headers today. I will have pics and e.t. when available.

my 436-2street motor makes 660hp according to the moroso slide method with only 11passes on it so far. now factor in drivetrain loss with 11%converter slip this motor would probably make bout 750hp on alot of dynos around here.im anxious to see Ryans dyno results just have to compare using the moroso slide method.

Ryan, how difficult was it to fit the 4.25 crank into the X block?? Were you using 2" pins?? Whose crank is it, shelf or custom??