blk3rdgen91

I know this has been discussed but many people are scared of this cam or just think its too much. I have a forged 355 lt1 ported stock heads 1.65 roller rockers...bringing my cam to .604 and .599 lift and intake duration @ 242 exhaust .248 and 1 3/4 dougs long tube headers
Now heard this cam can peak after 7000 rpms which for the optispark would be a problem..I need real world figures here from people who have ran or seen this cam ran. What top end set up would make awsome figures, I know that my heads are definetly holding me back but i have to say that this car has ***** with the set up it is now. please post your .02

1963SS

I've never ran the XFI 292 but I have used the XFI 280 a whole bunch on 383's. The lobes are a bit of a PITA to control and it makes a little noise but it screams on the big end and makes real good power down low. Works great with a 3000 stall converter.

You're going to want a great flowing set of heads to use that cam on a 355. Why do you want to go so big? The number one mistake that many people make is to over cam an engine and driveability suffers. You can make just as much power with a lesser cam and have better manners. A milder cam designed for your engine would be faster too. IMHO.

blk3rdgen91

semper fi gunny...yea i understand that the smaller caml could produce more power with the top end i have now , but who has ran this with its full potential no one that i have seen so far...Have the cam in there already and was running into this dilema of bigger cam vs smaller cam what are my potentials with this monstrocity of a cam?

96capricemgr

iTrader: (1)

The peak power rpm depends in part on supporting parts like headers, heads, and intake, valvetrain. Those 1.65s might make it a little difficult to control and have you peak low because of it. Some guys have it peak down around 6500, if you dig through old posts by fergymoto you will find he had it on a stock shortblock with Lingenfelter heads and the pcm ran out of rpm at 7000 and it had not peaked. The Lingenfelter heads worked great and let the cam keep pulling and making more power.

License2Ill

iTrader: (1)

Peaking lower wouldnt be such a bad thing in this case.
Anyone have some power figures tho. It is a monster. But so should output be in the right combo...even in a 355.

joelster

It seems like i've typed this out 100 times in the past month. I have that cam in my stock shortblock 350 with mildly worked TFS195 heads. The heads flow around 255-260cfm, nothing special. I also ran a single plane intake which helps up top. The car pulled real strong from 5000-6500, then fell off a tiny bit. I shifted all day long at 68-6900. With some better heads i'm sure I would have needed to go over 7k. I ran an 11.11 at 121.65 at 3100lbs in 1250ft da.

License2Ill

iTrader: (1)

Wow a tenth from 10's.
U think those AFR 227's could do better?

96capricemgr

iTrader: (1)

For comparison here you have another car with ported gm heads and intake with a 228 intake cam actually going 10s at 3800lbs.
https://ls1tech.com/forums/lt1-lt4-m...1-119-7-a.html
Yes Cecil in december is awesome weather BUT there is also a 700lbs weight difference which IMO is a bigger deal.

joelster

LOL, awwwwwww taking a shot at me? Should I feel bad that an Impala SS went faster than my 350? I don't, not one bit, there's always someone faster. My 350 engine isn't an all-out max effort deal. Pat happens to be a cool dude, unlike yourself. If I had to do it again, I would have went with a better head like an AFR 195 or the TFS 21 degree deal.

Want me to pick on your car now? LMAO, I could be here all day. You should bring your tri-colored taxi down to the shootout and show me up.

Not sure what your comparison has to do with the OP's thread and the questions he asked. What is the thread title again? Oh yeah, what heads to go with an XFI292 cam. He wanted real world results from someone who runs this cam. That's exactly what I posted.

Puck

iTrader: (17)

Fair comparison? I'm sure those 200cc CNC'd heads flow ~255 like his TFS's did too huh? . You can't mention the 700lb weight difference without also mentioning the 40cfm cylinder head difference.

As impressive as Pats car is, it has nothing to do with this thread or anything posted in it.

Those are way too big for an RPM limited 350, but some AFR 195s would have picked up some for sure.

nitrous2fast

iTrader: (2)

If staying with that cam... no matter what head you decide to use, i would suggest a steep rear gear to keep you higher in the rpm band.

xtreme2001

i have this cam in a 383 sbc and it has run a 7.04 @99mph in the 1/8th with a 1.47 60 ft in a 94 z28....the engne is going in an s10 now....the heads are cast iron world products sportsman 2's with 1.6 rocker

96capricemgr

iTrader: (1)

The above post was simply a statement about how you don't need the biggest shelf cam Comp offers to go fast. People too often look at results without context.
Far as "flow numbers" way to benchrace, let's look at it as "touched up" aftermarket heads and converted intake compared to GM castings.

Far as what heads would work, if ported GM heads can get that result with 14 degrees less duration.......................................... ...

BIGCAT7274

We run that cam with Afr210's. The 227 would be better.

joelster

Yeah no kidding, but he already OWNS this particular camshaft.
All you do is benchrace. Show up at the shootout. Tell us at the shootout how fast and amazing your own car is and how inferior our cars are. Tell me why Pat Gish's car is almost 7 TENTHS faster than your own car with the same topend? Or am I taking his performance out of context as far as how well setup his car is?

On Pat's car yes, on your car no, lol.

SS RRR

iTrader: (2)

Here's a fun fact: Statistically your old stock block setup blows away your new setup.

joelster

100% true. I also had 4 years to tweak it from 12.4's to 11.1's.

I'm pretty sure with a few years with my new engine it will be running a lot better. Nobody runs good out of the box. It takes time.

forgedlt4

i had that cam on a 383 with home ported LT4 heads. full weight, 6 speed. 1.7 60 foot.


ran a 12.0 at 115.

it might have ran slightly faster, but i ran out of gear just before the end of the track.

BIGCAT7274

aww come on. you mean you have to work at to get these things to run like they do. by the way some of these guys post all you have to do is slap a cam in it and get a mail order tune and your all set to run tens.

SS RRR

iTrader: (2)

You aren't as dumb as I thought.