[Garry Sr]

I had to bail from the race section, they had me surrounded by wide-ports, pro-ports,monster cams, things I haven't even dreamed about yet... and then there was the cages...

....so anyway, what do you guys think?
Block:70 400 35 over
Crank: Eagle 4.25
Rods: Eagle 6.8 H-beams
Pistons: Mahle flat tops (power pack)
Cam: Comp cams 51-226-4 H-Flat tappet
adv. Dur: 294/306
Lift with 1.65: .570/.575
Heads: Edebrock 61519 out of the box 72cc CNC
Intake: Victor with 4150 flange
Carb: Holley 850

Compression wise I should be sitting at roughly 11.2 to 1

I'm thinking this combo should pull an easy 500HP. Am I being overly optimistic or am I selling myself short?
__________________

[rexs73gto]

The 1 you have right now should have you in the 500HP range at somewhere in the higher rpm area of about 5500-6000. Thats ok for a 400 even with the longer stroke. The only thing you need to do now is make sure you have good oiling to the bottom end so you don't lose all the oil out of the pan & then don't leave any oil to keep the pressure up. I would go to a bigger pan , more quanity of oil to make sure you always keep enough down there. The only thing you didn't mention is wheather or not you have 4 bolt mains or not ? Plus I can only assume that the pistons are forged ? I would also like to see you use the new 1 piece Viton seal that Butler is selling. I have one right now for my new build & it looks to be a great seal. It's not much more then the original Viton seal only about $ 8.00 more but sure is a good looking piece.

[Garry Sr]

The short block's already assembled and I used the rope seal, wish me luck. The block is drilled for 4 but only had 2 bolt caps. The pump is a Melling 54D-S and I just ordered a Moroso 7qt pan. The pistons are forged and coated flat tops with two eyebrows.

[AG]

What is the duration at 0.050" of the cam?

[Cliff R]

It will fall out of a tree and make at LEAST 500hp/540tq.

We build a 455 a few years back with the 87cc E-heads and non porting anyplace, Crower 60919 cam (RAIV clone), 1.6 Crower rocker arms, 467cid, and made 505hp/551tq. Installed in a street driven 71 FB with 3.90 gears and 10" Continental converter it ran 11.50's over 118 mph on DOT's and driven to the track, race weight was 3900lbs w/driver......Cliff

[74Grandville]

XE294 250/256 @.050

http://www.compcams.com/Company/CC/c...csid=1206&sb=2

[rtanner]

good combo stay w it exactly as is, then tune it tweak it put a couple hundred [passes on it and it will be fast fast

[Garry Sr]

Every part I listed is either here or on the way other than the rockers, pushrods, and I need a new carb. She's going together.

[Skip Fix]

Look at my pump gas 455 int he 78-"only" a 0.030 455 not a 4.25 stroke 296/304 239./247 @ 0.050 UD HFT TorkerII Holley 850.

[Garry Sr]

The Skip is in but he didn't post a link..... get you're **** together man.

[rexs73gto]

Garry, I know theres a lot of guys who don't really care for the RAIV cam wheather it be a Crane or a Crower Or lunadi grind but I like it. It makes good power for my use which is mostly in town driving as I run a 3:73 rear gear which while I'm driving keeps it right in the sweet spot most of time. Yes ther are some cams out there that may be a better choise but at this point I havn't herd any one say which one that is. There are so many cams on the market that I don't see any body using any one cam as the cam of choise yet. The RAIV still seems to be the go to grind for a lot of guys building street Pontiacs. Plus the guys building for both street & strip. I think Mac did his homework when he designed that cam.

[Cliff R]

Like the RAIV cam or not on the dyno it made more power than a Comp XTQ lobed flat cam with 240/248/112 specs, even thought the Comp cam had 10 degrees MORE duration at .050", and .060" more lift.

The dyno testing was done back to back on my last 455. We removed the Comp cam and installed a custom ground hydraulic roller cam with .361" lobes, and 230/242/112 specs. It made 3 more HP than the RAIV grind and 4 more ft lbs torque. Even with the custom ground HR cam peak power fell from 5600rpms back to 5400rpm's.

This clearly shows not only how good the RAIV cam is, but that we cam mimic a very well chose HR cam by adding Rhoad's lifter and high ratio rockers to it.

Vacuum at idle with the HR cam was 13.5", and 12" with the RAIV cam, so HR cams really do get it done well with a little less seat timing and not as much overlap.

The 240/248/112 Comp flat cam made 14" vacuum at idle, and peak HP fell clear back to 5200rpm's.

We re-installed the engine in my car and did some track runs and compared numbers. Since the runs were not "back to back", and not exactly the same weather I had to average the numbers.

The car picked up a solid tenth and 2mph with the HR cam vs the RAIV grind. Best ever run in good air with both cams were 11.64 @ 116 for the RAIV, and 11.52 @ 118mph for the custom ground HR cam.

Even though it is often considered a somewhat "outdated" design, the RAIV cam is a very good choice for a 455 engine build with moderate compression on pump gas. With the RAIV cam in place I could run any grade of pump gas without any detonation issues anyplace. With the HR cam the engine required at least 92 octane, so the slightly smaller cam with less overlap did increase dynamic compression some and build more cylinder pressure to a point where higher octane fuel was required.....FWIW.....Cliff

[shaker455]

Originally Posted by Garry Sr

I had to bail from the race section, they had me surrounded by wide-ports, pro-ports,monster cams, things I haven't even dreamed about yet... and then there was the cages...

....so anyway, what do you guys think?
Block:70 400 35 over
Crank: Eagle 4.25
Rods: Eagle 6.8 H-beams
Pistons: Mahle flat tops (power pack)
Cam: Comp cams 51-226-4 H-Flat tappet
adv. Dur: 294/306
Lift with 1.65: .570/.575
Heads: Edebrock 61519 out of the box 72cc CNC
Intake: Victor with 4150 flange
Carb: Holley 850

Compression wise I should be sitting at roughly 11.2 to 1

I'm thinking this combo should pull an easy 500HP. Am I being overly optimistic or am I selling myself short?
__________________

You should be right in the ballpark.

[hectore3]

Originally Posted by shaker455

You should be right in the ballpark.

Im thinking the same.

[hectore3]

What are you doing for oil control and ignition?

[Skip Fix]

I'll bet 525-550hp with the CR. Mine dynoed 525 but based on mph is closer to 550-570 depending on calculator. I'm an Ultradyne cam fan. 78s pump gas motor has one from Harold when he was at Lunati. I had it ground on a 112 LS. 1.8 rockers intake/1.72 HS on the exhaust.
Bullet has their lobes now also-where I got the roller for the 409/470. 251/251 again a 112 LS. Butler used to handle them as his go to cams when UD was still going.

[Garry Sr]

Appreciate the input guys. I'd like to get the engine dyno'd but I was over budget as soon as I thought about building it. 500 works for me as a min. 550 would make me smile a little bigger. The car still needs a ton of other work but I'm over the high-dollar hump.

[Garry Sr]

Originally Posted by hectore3

What are you doing for oil control and ignition?

I'll be drilling & shimming the stock windage tray and for now I'll be running an aftermarket H.E.I.

When I start spraying the engine I'll probably want to go MSD.

[rexs73gto]

Gerry, I know your working on a budget but there is 1 thing you may want to get & it's not that expensive. Just for the the sake of safty you may want to pull your stork main bolts & install a set of ARP main studs. You won't have to change any thing to put them in & by using the main studs you will give your bottom end about 50% more clamping power then the reg. main bolts. Studs just because they are holding the mains down just by the way they are put in give you a better clamp load. I used the 4 blot main studs from ARP when I built this engine & I have to say just from they way they go on makes me fell more secure. I know it's to late fro you to go with the 4 bolt mains as you would have to pull your engine all apart again to have it line honed when you added the 4 bolt but if you would have had it done in the begaining it would have been well worth the money expesically on a 455 with the big 3:25 crank. But the weak point is gnerally not in the cranks on a Pontiac engine but it's always better to have the extra safty of the 4 bolts on them anyway. But if you follow along with the ideas you've been given here you'll have an engine that will be right where you want it to be. As I said before I like the RAIV cam from Crane & have used it on my last 3 engines & they all ran great. I had it in 2 455's & 1 .60 over 400. Like I said Mac knew what he was doing when he designed that cam for Pontiac for the 400, little did he know that how great it would work with the 455's. Of course I'm sure he played with it in the SD to, it just wouldn't pass emissions proberly.

[Garry Sr]

Originally Posted by rexs73gto

Gerry, I know your working on a budget but there is 1 thing you may want to get & it's not that expensive. Just for the the sake of safty you may want to pull your stork main bolts & install a set of ARP main studs. You won't have to change any thing to put them in & by using the main studs you will give your bottom end about 50% more clamping power then the reg. main bolts. Studs just because they are holding the mains down just by the way they are put in give you a better clamp load. I used the 4 blot main studs from ARP when I built this engine & I have to say just from they way they go on makes me fell more secure. I know it's to late fro you to go with the 4 bolt mains as you would have to pull your engine all apart again to have it line honed when you added the 4 bolt but if you would have had it done in the begaining it would have been well worth the money expesically on a 455 with the big 3:25 crank. But the weak point is gnerally not in the cranks on a Pontiac engine but it's always better to have the extra safty of the 4 bolts on them anyway. But if you follow along with the ideas you've been given here you'll have an engine that will be right where you want it to be. As I said before I like the RAIV cam from Crane & have used it on my last 3 engines & they all ran great. I had it in 2 455's & 1 .60 over 400. Like I said Mac knew what he was doing when he designed that cam for Pontiac for the 400, little did he know that how great it would work with the 455's. Of course I'm sure he played with it in the SD to, it just wouldn't pass emissions proberly.

I've actually been thinking about tearing the block back down Rex, I think it's more of a idle hands thing than anything else.