LastPewterZ

iTrader: (1)

My point exactly^^

LastPewterZ

iTrader: (1)

Ya, I know, I didn't know what to think when I found that out. It's got the LS6 intake though and so the heads shouldn't be making a HUGE difference, right?

STRIPSTAR

iTrader: (4)

with mystery heads you may have an underlying issue there. I would get some good dual valve springs also - they are cheap.

PewterScreaminMach

iTrader: (7)

You could always pickup a set of used, low mile 241 castings for a couple hundred bucks at the most. Then redyno and see if that was the issue. It might be some work but it would be cheap in terms of parts. Just a thought. Good luck with it.

brad8266

iTrader: (23)

From that graph, the TQ looks OK until after max TQ. After max TQ it seems to drop off at too high of a rate, its a pretty steep slop after peak TQ, that is why the peak HP is not high. TQ up to 5K doesnt look too bad.

LastPewterZ

iTrader: (1)

It still should respond to mods the same as any other 98-2000 with an LS6 intake swap. My friend has a 98 vette with a TSP 228R cam with an LS6 intake swap and a couple less mods than me and made 390 rwhp. Not to mention it's got over 100k on the clock, so wtf it can't just be the heads.

PewterScreaminMach

iTrader: (7)

Not to be a dick or anything, but it CAN just be the heads. I'm not saying it necessarily is, as I agree it's not the most likely scenario, but the fact is you have a set of heads on there that are not only worse that the stock heads, but you have no idea where they came from. At some point, someone swapped lower quality heads onto that car. What if something was wrong with them, so someone sold them to a previous owner telling them that they were some kind of aftermarket head. If the previous owner didn't know much, he might have bought it and had a friend help him with the install.

Again, I'm not saying this is definitely the case or is even very likely, but it is not an impossibility. We've all seen stranger things happen. Take into consideration the fact that you gained 42 rwhp with just a cam swap. That in itself is not on the low end of gains I've seen, although they of course can be much higher. Just trying to help.

Patrick G

iTrader: (14)

You make it sound like 853 heads are junk. LOL. For your information, the 853 heads have the same port size and configuration and use the same valves as the 241s. Only the casting process is different. If there is a flow difference between the 853s and the 241s, then it's only 2-3 cfm, hardly anything worth swapping heads over. This is why you see as many 1999-2000 F-bodies making big power cam-only as you do 2001-2002s. If the intake, cam and headers are the same, the earlier heads will lay the big power down too.

I would recommend looking into other issues. A compression test will tell if the cam is installed wrong and a leak down test will confirm if the motor's healthy.

PewterScreaminMach

iTrader: (7)

I may not have been clear, so I apologize. I wasn't suggesting that he was seeing low numbers because he had 853 heads. I was suggesting that if all else fails, consider why someone would have swapped 853 heads, a (technically) slightly INFERIOR, not SUPERIOR, head for the application, onto a car that came with 241 heads. I was suggesting that perhaps something is wrong with them, or that this might suggest something else wrong with the car, since they are obviously not stock and I can't see why someone would in their right mind put them on the car unless, say, they were converting it back to original.

Which brings up an idea: was this car stock when you bought it? Perhaps it wasn't always stock. Perhaps someone picked these heads up cheap off of someone so they could remove their aftermarket heads and sell those separately. Everyone knows that you can sell a bone stock car for more than a modded one, with the possible exception of maybe some show cars and race cars.

Again, not trying to diss the 853s , just trying to find out why someone might put them on that car and suggesting that perhaps it's worth investigating if other options don't find the problem. I definitely don't know enough about heads to suggest technical advice on WHY these particular 853s MAY be a problem. I'll leave that to Patrick G.

LastPewterZ

iTrader: (1)

I'm gonna go ahead and do a leakdown and compression test and start there. I still don't think it has anything to do with the heads due to the fact that it made good numbers with these heads on a lid and catback setup. (321rwhp/333rwtq) And it was on the same dyno.

PewterScreaminMach

iTrader: (7)

Sounds good. You're probably 100% correct. I was just trying to come up with anything I could think of since you seemed pretty frustrated with it.

Let us know how it goes!

LastPewterZ

iTrader: (1)

Thanks for all of the helps guys, at least I know where to start It truly is frustrating

ScreaminRedZ

iTrader: (3)

Some cars just make more power than others. There are reasons, but it's not always one single thing causing it. I bought my cam used from a friend. He had a 99 SS and it made 367. I put it in my 02 Z28 and it made 420 on the same dyno. We have different brand headers and cat-backs and mine has an LS6 intake, but those are the only major differences. Not really enough to warrant a 53 hp jump from one car to the next in my opinion, but it's there none the less.

ls1chris

WEll i have a very similar setup as this and was also disapointed with hp it put down on the dyno mine did 365 hp with 347 Tq with a 1998 ls1 with Stock 806 headswith prc dual springs and 7.4 pushrods,Lt headers.410gear and BBk intake .But I wouldnt get to caught up with Numbers after all a dyno is just a tuning tool take it to the track see what she runs.So far with my mods and Being a baby about launching at the track ive ran 12.30s at 114 mph and 7.94 in the eight But i think its capable of some 12.20s easy with better launch if not bette So i was pleased with this.And im sure with some better heads the car will Hp more That seems to be my problem but It still runs great and for a full weight car drivin every day i couldnt ask for more and theirs alot left in it.So Dont get to caught up on Numbers imo

ScreaminRedZ

iTrader: (3)

Damn, 12.30's at 114 is a great time for that power level!

LastPewterZ

iTrader: (1)

Well that's encouraging, thanks man

bad6as

iTrader: (17)

i dont know about that my 3.90 gear 346 rwhp car traps 112

ls1chris

theirs more left in my car thaugh guys im mean im leaving alot on the table not being able to Launch hard due to the stock rear but still i was pleased with the results

PewterScreaminMach

iTrader: (7)

1) What is your ET? You make no mention of it, so I'm assuming worse than a 12.3. And 12.3 at 113 with 365rwhp IS a good time for that power level.

2) You're racing in Maryland, and I hear nothing but great numbers from down there, so that's probably helping you out a lot.

3) You only have about 20rwhp less and you're trapping 112, so why wouldn't his trap speed be considered good?

bad6as

iTrader: (17)

he has a 232/234 cam and traps 113

thats not right he should have another 3-5mph