Firevette

Its 222/230 .509/.528 w/1.5 rockers. 112 LSA

I'll be running 1.6's @ .543/.563

I wanted a little more RPM/power/rough idle than the hotcam.

Anyone using it now or previously?

General impressions? Street manners? Idle? Anyone dyno with it?

I'll be running it with a miniram, afr 195's, and a ZZ4 shortblock.

tpi 421 vette

I have used that cam in alot of motors. I have used it in several 383's, and even in a 421. It's a nice streetable cam, makes good power. I made 416rwhp in the 421 with it. The 421 was also a AFR 195 miniram motor. It's a little more aggresive in a 383 or 350, but works well. I think if you want real good street manners, and throttle response, you will be happy with it. And it will pass emissions if that is a concern.

Firevette

Thanks for the info.

I dont really need great street manners, just streetable. This is going to be a weekend driver/car show/friday night dragstrip car/fun toy. I am planning on taking it to BG though.

I really wanted to run the GM 847 but crane says it peaks around 6,800 rpm. I really wanted something with a max of 6,500 so I don't grenade the ZZ shortblock on the first night out. Thus the 846, because I havent found a lot in between the two.

96GS#007

846 at idle in my LT4...

GREGGPENN

Wow... That sounds smoother than a lot of HOTCAM's posted here!

GREGGPENN

What did you think about 268 or 280XFI cams? Too much lift for the springs? With 195's, I wanted to get above .550"

Firevette

Its my impression that they are ground on a 113 LSA, and people have not been happy with the power they have been putting down. Ive also heard that beacause of the reduced overlap they idle rather mildly, which is fine......but if im going through all this trouble I want to know there is a cam in it.


As for the springs, I dont think its too much. I would just have to swap back to 1.5 rockers....but im no guru. I have heard of some f-body guys having spring problems with the XFI grinds...

Firevette

I found this video in a search for the GM 846. What RPM was the idle set at? Was it in a 350 LT4? Do you still have it for sale?

Ive seen a lot of hotcams that sound huge before a good tune, and mellow as can be after. My ZZ4 is curently in my monte carlo with a holley DP. I have it idleing around 650 RPM...It sounds like a monster.

GREGGPENN

Did you get the base springs or an upgrade? I got an upgrade to higher tension springs. But, I'm now considering less radically ramped cams -- since XFI ramps are only worth 10-20hp (in my case). Also gotta wonder how much longevity is gained.....

FWIW: CC will let you specify how any cam is built. For no extra charge, you could specify any LSA/ICL you want. So, you could pick 110-111LSA and adjust ICL for where you want power. (later = higher, so maybe 111ish? 109 is standard ICL -- which is also considered 4-degree advanced). I believe wait for custom cams are 2-3wks.

That would provide you with the option to get more lift -- holding everything else about the same. Depending on your exhaust system, it might get you 10 or more hp at higher rpms -- and take more advantage of the 195's extra flow capabilities.

As you elude..., the 113LSA + 109ICL would create a flatter hp curve. This makes is idle better, be more responsive off idle, and produce more vacuum. Surprisingly, it can help at higher rpms too (not mid-rpms). What you want to do would create more mid-range power, lower vacuum, and yes, create a rougher idle.

reoch999

So THAT'S why you needed that happy hooker from the for sale section... FWIW, sounds like a good combination to an amateur like me. I opted for the CC503 (more aggressive ramp profiles with less overall duration) for my stock bottom end LT1, somewhat similar cams and sounds like a somewhat similar setup. You'll probably have an advantage though with those AFR 195s.

Firevette

I have the standard springs. I dont have the specs in front of me, but they are supposed to be good to .600

It was my understanding that anything with an LSA less than 112 would be difficult to tune? I wont be tuning myself, it will be a custom mailorder for now. (pcm for less or similar) Maybe a dyno tune later.

Firevette

GREGGPENN

I've heard 110LSA as the border. 113 can't be THAT bad (on an XFI) if 112 is "the limit"! (BTW: 2 degrees per 1 LSA) Anyway, several people have suggested 111LSA for me.

Regarding springs....AFR considers base springs good to .600" lift as you say, but they don't recommend them for all cams with less than .600" lift! If I were you, I'd narrow my choice to 2 or 3 cams, then call the AFR tech line. Relay the specs and see which (if any) they recommend on the base springs.

Even though the XFI cams lift less than 600, they recommended the spring upgrade to insure valve control with those ramp rates. And, according to what I see, there are really lots of cams with similar slopes.

Longevity was one of my goals. I don't want to install a bunch of mods designed to last 20-30k miles. And, according to AFR, that goal eliminates a lot of choices. IOW, they consider many head/cam mods as having that type of longevity.

Maybe milder cams like the hotcam aren't so bad after all!

gp

rickneworleansla

I just got this yesterday for my LT1 along with all my other parts. It is a custom cam from LE. Why settle for a shelf cam when you can pick the specs you want. I told him what I was looking for in power, sound, street manners, etc., along with all the mods I have. I had it on front my door in less than a week. PCMFORLESS is emailing the tune.


226/234 565/565 109 LSA

383vett

I ran that cam for years in a 383 with a SuperRam. It was a very good street/strip cam. Good idle and good power. Car was in the low 11's. You'll be happy with it.

Firevette

I talked with AFR today. They said the 846 shouldn't be a problem, well under the limits for the springs.

LE?

GREGGPENN

LE = Lloyd Elliot

Lloyd recommended either his 218/222 or 222/226 cam -- using a production 350 bottom end. Both assumed good headers and exhaust -- which means little split is required.

That 226/234 cam + AFR 195's + MR can make a ton of power, especially from 5k to nearly 7k rpms. Is that where you really want it? Plus, that extra power above 6k rpms comes at a cost of "bleeding" hp down low. Just what extra duration does.....

The simulation I have run showed a smaller cam peaking at 6.7k rpms. By reducing my original choice, I gain more low-range power without giving up much below 6k rpms. Smaller LSA also helped with mid-range power.

I will also add that my "guy's" recommendation was also smaller than Lloyd's. Without installing both cams recommended, I don't know who's right.

There is an optimum cam for the rpm range, intake, block, and heads you're using. What steps have you taken to determine that range?

Or is your whole goal to get a nasty idle? Maybe you should ask if CCams can adjust a "Thumper" cam to get enough LSA for your ECM? Or... just skip the tune!

gp

Firevette

Always wondered who that was.

No, not really. Id like it to peak from 6-6.5k rpm



Intresting.

Afr said I should be making good power up to 6.5k, I have the "street" eliminators #1040. Gmpp says the 846 should make peak hp around 6.2k. The M/R should pull well in that range, after the tpi would normally drop off.

Hardly. I want to get the most power out of it that I can. If it comes with a nice sound, thats an added bonus.


Im still learning as I go, not that I haven't done any of this before. #1 FI is new to me. Everything ive ever built has been carbed. #2 a lot of tech info goes in to choosing aftermarket components. Im used to the "taking the die grinder to some heads" way of making HP, so I still have much to learn. I guess you could say im oldschool and low tech.

Thanks for the info, looking forward to your reply.

rickneworleansla

I got the springs cheaper by ordering through him also.

96GS#007

The idle was set to 875rpm vs stock of 700. I also tweaked the closed throttle spark advance. I no longer have the cam available, it was sold.