[D70]

Hey All,

Received my block back from the shop a little bit ago, and if anyone had a moment to desktop dyno my combo for me, would be appreciated!

Here is some info off the of paperwork, hopefully this is enough info:
- 454 90's 4bolt crate block + .30 over
- Heads: AFR 305cc cast CNC / Milled to 116CC
- R+R Cam Bearings
- Federal Mogul Speed Pro Lifters
- Crane Cam Hyd Roller (139011)
- Cam Spec: 226.587 / 112LC. 1.7 / EX 234.575 1.6
- 1.60 HiTech Stainless Rockers (Ex8 In8 1.73
- Speed Pro Rings (R9904.030)
- SRP Pistons (212135) 119cc 10.1 Compression
- Push Rods 3/8
- Holley 750DP
- Edelbrock RPM AirGap (7562)
- Hooker Headers / 3'inch to Flow 40' series.
- MSD 6AL

If thats not enough info let me know, I have to contact the shop about paperwork tomorrow anyway, somethings on it don't make sense / can't read the writing.

Thanks!

 

[GRN69CHV]

I plugged the numbers in real quick. Don't have the 305 air flow data, but do have the 315 data loaded. Don't know how the 315 data would apply to the smaller bore as I think the AFR data is published on a 4.5" bore, so flow would be reduced a little. However it works out, only a dyno session will reveal for sure. I came up with 580HP using the 315's. For comparison, the GMPP (ZZ502 heads) 290CC intake runners with the same cam post numbers in the 545HP range. Big difference would be if you used a cam that took advantage of the high lift flow. The AFR's (from what I have read) work well when the lift gets into the .600 - .700 range. I would have a hard time believing that Crane hyd roller would produce much over 500HP in anything less than 500CI, regardless of the heads - just not a very big cam. Going back to the article that Chevy high perf did on the 454HO motor, that cam only made about 470HP with a warmed over set of GM rec ports. Whether the swap to set of AFR's is good for 100+HP is the question - I don't have any first hand experience with them. Whatever the hard number is, it will probably have great off throttle response, a very mild idle quality and I would think it should have a useable RPM range of about 2000 - 6000. Very similiar to my motor.

Good luck.

 

[mr 4 speed]

580 HP from a 226/234 duration hydraulic roller?

 

[cmt454]

580 HP from a 226/234 duration hydraulic roller?

I agree with that question. There is no way!

 

[onovakind67]

I've seen dyno tests of 365" SBC's making in excess of 600 hp with cams in the 235° @ .050" range. Add 90 cubes to this and I don't see much of a problem. We built a 540" motor for a customer last year that made over 700 hp using a 234°/242° HR cam. Here's a quote from Joe Sherman:

"My plan is all based on my experience. I've researched the relationship between port size, flow numbers, and horsepower. I'm shooting for intake flow of about 320 cfm at .600-inch lift, and exhaust flow is targeted at 230 cfm at .600-inch lift. I normally coax about 2.3 hp per cfm in race engines, and if I can come very close to that target with this 365-inch package, I'll win the Challenge. This engine has potential to 675 hp, but that number would require too much camshaft for the way you're testing these engines. So, I'll run a cam with about .590-inch lift with about 236 degrees at .050. I want the engine to peak between 6,300-6,400 rpm, and I'll play with the combination until I get it the way I want it."

 

[D70]

Hey All,

Thank-You very much for the info! So its safe to say, off the top without a dyno you would say about about the 500hp mark or so, because of cam selection etc... ?

In selecting a cam, I was going for something a bit mild, as this car will only see the track once or twice, so I didn't want anything to radical (at the moment). The 500hp mark was something I was hoping for, with this engine setup, 700r / 12bolt, I was hoping to put atleast 300-400hp to the rear wheels.

Later on after the car is back togeather, and if needed the cam would be the first swap before any 'chargers, for sure!

Two big projects down! Just need to paint the car now, and assemble!

First big project:
http://www.chevelles.com/forums/showthread.php?t=99112

 

[TW]

This is exactly the same cam I ran in my 502 except mine had the step nose for a Gen VI (cam pn 168731). This cam is very strong in the low to mid range, but will not rev. I ended up turning an [email protected] in the 1/4, but that was with traction issues and the fact that I ran out of steam (valve float) at least 100' or more before the 1320' mark. I think if I had 3.42 or 3.55 gears, instead of 3.73's, it would have done slightly better. The cam idles with a little rumble to it and pulled about 14-15" of vacuum (in the 502). Your heads should flow better than mine, so your results may be different. Throttle response is unreal......at any rpm. It really is a decent street cam.

I pulled the cam out and installed a Lunati solid roller (251/[email protected]).

 

[GRN69CHV]

If you read my entire response you will see that I said, I don't see how that size cam will support much over 500HP, but the unknown factor is - just what are the heads capable of and just what effect does these have in making HP. Also keep in mind, this is about a 10.25/1 motor. Keep in mind, a 226/234, .587/.610 hyd roller is the equivalent of about a 234/242, .607/.630 solid roller. The unknown is just how well the heads actually flow on a smaller bore. I have seen some dyno infor from Mike Lewis for combos that run AFR's and they are typically always in the 600HP range. As I stated earlier, this is just a sim program, calibrated to a baseline 454HO motor and then adjusted for the individual components as added in (ie - heads, CR and cam). Did this real fast on the way out of the door this AM and did not check all of the inout data which I will do later this evening and then post back.

EDITED 4:26PM.

Looked up a recent post by Mike Lewis for a 489 (4.280 x 4.25) with AFR 315's, 9.8/1CR and a Comp 242/248, .540/.560 hyd roller. He posted 620HP at 5900, 610FTLB Tor @ 4600. I am always skeptical regarding the sim programs, but given only a 29CI deficit and 16* less cam timing, but more lift, the 40 HP difference between the 460 (sim) motor with AFR 315's and the 489 motor Mike actually dynoed with AFR 315's, well, for a sim program, that's bad. Heck, it was recently posted that a ZZ454 with the stock 211/230, .510/.540 cam was actually dynoed at 490 (think that's the number) by Sallee Chevrolet. Add in more cam, compression and a lot more head is 90 more HP really that far off target?

 

[orange2]

can i ask y a smaller hydro roller is equal to a bigger solid roller? Seems to me a smaller solid roller would out perform a bigger hydro?

 

[TW]

Orange2, from what I understand is that because of the required lash setting of the solid roller it works out to roughly 8° less duration at the valve than the quoted 0.050" numbers. The solid roller theoretically makes more HP due to more aggressive ramps even if the cam durations were identical.

Tom

 

[Yellow68SS]

Orange2, from what I understand is that because of the required lash setting of the solid roller it works out to roughly 8° less duration at the valve than the quoted 0.050" numbers. The solid roller theoretically makes more HP due to more aggressive ramps even if the cam durations were identical.

Tom

But the lash is taken all up by .050 lift. and the Advertised duration is rated at .020 which also has taken up the lash.

Not sure about this just what i think from looking at the numbers.

 

[GRN69CHV]

Only going by what I have been told (or at least, thought I was told). The lift difference is correct because solids are always quoted based on gross lobe lift X rocker ratio, not net after lash. As far as the duration at .050 lift, this is also measured at lobe lift, so for a given .050 duration a hyd cam would expect to have the lifter moved .050 and also opened the valve by the same amount X the rocker ratio [BBC = .050 x 1.7 = .085], but a solid with .020 lash would still move the lifter .050 but the effect at the valve is only [.030 x 1.7 = .051], you lose the first .020 of lifter movement due to lash.

Hopefully this makes sense. Cams are measured at lifter movement, not valve movement. Regardless of what the lifter sees, flow deosn't occur until the valve moves.

 

[orange2]

yea i guess it does make sense. I had just always heard that a hydro acts 10 degrees of duration bigger (compared to a solid roller) Just never thought about the lift and the lash. I guess I kind of wondered why the hrdo roller never seem to have as much lift, this explains it.

 

[TW]

GRN69CHV is correct. The numbers for a solid roller are measured at the lobe (or lifter) and do not take into account the lash.

Tom