destroyerSS

iTrader: (2)

got my tune yesterday and my final #'s were lower than i had hoped for. Totals are 415HP & 375 tq with mods in sig. I spoke with NOGO & Sean at EASTSIDE and they think it has alot to do with my headers{MACS} because on my dyno sheet you sould see it building power but then at around 5700 it just flatens off and stay's the same to 7000rpm BTW I would like to thanks the guys at EASTSIDE for the great service and to NOGO for having to put up with my million ?'s all day.Your effort is greatly appretiated. Scott and sean it was nice to meet both of you as well. KOOK's will be ordered monday I HOPE!!!!

KGSloan

man, that sucks to hear. i know you were wanting more.

what did the car dyno cam only?

that setup should definetly peak above 5700rpms. hopefully it is just the headers causing the low numbers. it is hard to believe that the headers are really gonna give you 35 more rwhp, but maybe.

do you have a cutout in your exhaust? i've seen y-pipes eat up 20+rwhp before. cutouts in the y-pipe might be something to consider.

Benjamin Russick

iTrader: (1)

I don't think it's the MACs...they usually shine at the top of the RPM band. Did you cut the ball-flanges off and use a better collector? Are the rockers installed correctly (no flame, just asking)? Are you taking the GMAF calibration out of the equation? That does seem low...especially in torque. Good luck!

offaxis

iTrader: (19)

415 hp at 5700 shows major potential . Now we just have to figure out why it flatened out. That cam should peak at 6400-6600 and pulled strong through 7 grand. I just saw a postwhere a guy picked up 15 hp switching from macs to a long tube header on a h/c car. Maby also try to check your fuel pressure uptop and possibly the rocker geometry. I had a friend with a trex / and heads that made 445 hp at 5700 the flattened out. Well 2 days later he had a colapsed lifter and messed up cam because of poor valvetrain geometry.

Just figured I would mention it.

offaxis

iTrader: (19)

Can ya post the dyno sheet?

thanks

Also take that crap maf off your car. Its well known to be junk and can defintly through things off

destroyerSS

iTrader: (2)

i'm confident that the valve train is set up good!! as far as the GMAF i would think that my A/F ratio would be all over the place but it was smooth. How much would the mass air hurt since it's only a 75mm? Probably not much!! I do not think it's a air into the engine problem.

PREDATOR-Z

Did you ever sort out your shimming on the Comp"R" s ?/
MAC's actually do better that LT's on top, it is down low where the LT's fair better. I doubt that the LT's will give you the extra 35 horses over Macs but it would be nice if they did.

SPANKY LS1

iTrader: (24)

I think you are seeing a "real" dyno number, not a dyno queen # IMO. Sorry to say it, more people have hit 415/375 like you and me than have hit 475/435 like a couple. I think your numbers are a little low, but as stated above, I wouldn't get your hopes up in the header swap, you'll probably see less than 5-7 peak IMO. I have seen Macs on several 450+ rwhp cars, and doubt they are hurting you signifigantly. I would make sure that the preload and valvetrain geometry is good.

Good luck, Shawn

JS

iTrader: (4)

I'd have to agree with Spanky...
All this dyno number BS,I dont believe any of it for a minute..

Why is it when someone else tunes or tries these setups they are down 10 20 30 40 RW,I'll tell ya why because its BS.I've been to alot of shops and one thing I can tell u,ESP's dyno is perfect and realistic.

Those guys just dont fudge or play games---->There HONEST about #....

I would look at the geometry of the valvetrain just for S&G but I wouldnt waste money on headers.

SPANKY LS1

iTrader: (24)

Yeah, I actually SOLD my last setup because I was disappointed by my low (compared to other, similarly modded cars) dyno, and it was ~8 months before I drove my car again. 415rwhp is a STOUT setup, enjoy it, run it at the track, don't get caught up in the whole internet dyno bragging rights thing, it'll drive you crazy.

Shawn

offaxis

iTrader: (19)

I personally wouldnt be happy with my combo if peak power came at 5700 rpms with a cam that should peak 800 rpms higher no matter what the numbers are. I think there is definitly a problem But then again what the hell do i know. Is the cam installed correctly? Not talking **** but it does happen. Are you running the comp r lifters?
Just trying to help

BTW Eastsides dyno is about 10hp lower than the dyno`s on long island here. Thats why I post my numbers from there.

destroyerSS

iTrader: (2)

I was told that if my preload was not right we would see a drop off. What upsets me is that the way it starts building power it looks like it should go to 430-440 HP

foff667

iTrader: (2)

yah id have to say if your peaking at 5700 there is something wrong...mine and pretty much everyone else that owns this cam peaks at 6200-6400rpms. Heres my graph

destroyerSS

iTrader: (2)

My power is peaking around 6200rpm but the problem is that from 5700-6200 rpm's there is only a 10 or so hp gain then at 6700 it start to go down alittle

Bryan Wilkinson

iTrader: (1)

I am curious as to why you went with a bigger TB and intake. It was not required You are not moving enough air to overtake the stock throttle body and intake. The stock injectors also had enough fuel to power your modifications. I am also curious as to the rest of your cam specs. Did you get a big enough cam for the LSX intake to improve your power range. There are several reviews out there now in Hot Rod Mag, and popular hot rodding, and Chevy Performance showing the gains with this intake, but it has to have a big enough cam. I agree and do not think the headers were the cause here. You are not bringing enough air into the engine for the headers to be a problem. If you are getting to 5700 RPM and then flatting out, it seems to me that the engine is either making all of the power that it can based on the amount of fuel and air you have coming into the system or you have something else that is not functioning properly.

In regards to the 7000RPM. If this is not a double spring setup on your valve train, you could be experiencing some valve float. If this is the stock valve springs or not a double valve spring you would be wise to keep it under 6500.


The comments listed here are an opinion in an effort to assist. This is not an attempt to start some flaming war or something.

Good Luck

destroyerSS

iTrader: (2)

Brian, My cam is TSP 231/237 598/595 112. injector were so my stock one's wouldn't have to run near max capacity. The LSX is a 78mm ported to 80mm not a 90 mm so it's not that much bigger. and the heads are a good flowing set from absolute speed 5.3L with 2.055 & 1.57 valve's with comp R lifters and comp 977 dual springs. I think the air and fuel parts are covered now it just removing them is were i think i have a problem.

JS

iTrader: (4)

If u peaked at 6200 and it carried flat to 6700 there is NOTHING wrong.My car has a little 224-580 cam and it peaked at 6100 and carried it to 6400.I was at 410 by 6100 and it stayed there until 6400.

FWIW,I shift at 6500 1 to 2 and 6400 2 to 3..

I think your fine,Look at the graph on this cam and u can see it hit 6300 and then falls off at 6500...

Your setup holds it longer so shift the car at 6700,thats where it falls off.

CHRISPY

LOL!!

That is PERFECTLY normal and actually a good thing.

10RWHP from 5700-6200rpm is good. Holding it to 6700 is VERY good.

Broad flat powerband is what you WANT!

I am not sure I understand what you are complaining about

foff667

iTrader: (2)

maybe its the raven catback

PREDATOR-Z

I agree, this is exactly what I'm trying to achieve. A flat curve till 6700 that allows me to stay at or above 400rwhp between shifts.
can I have your car??