Navy David SS

iTrader: (13)

A month ago put in new PP Stage II heads and TSP 231/237.

No problem with install. No smoke, no miss-fires. Put in all new EWP, plugs, TR coil relocation, etc, etc.

1st dyno #s: 413RWHP and 380+RWTQ. Some minor start up surge and was only running 26 degrees of timing and running a little rich.

Had the surge problem resolved by tuner. Bumped timing up to 29 degrees. Leaned out the top end just a bit. Added catch-can. THIS WAS THE ONLY CHANGES.

Went to re-dyno (track is not open yet and I got bored ).

New #: 374RWHP and 360 RWTQ (I was so pissed I did even want the sheets).

Per A-tap both dyno's the same: no KR, no miss-fires, O2's were rich (.915 to .950). Timing was at 29 degrees as programmed. I tried even the old 412RWHP program. Nothing. Still got only 371-375 - six dyno pulls.

Checked catch-can connection. Nothing seemed to be "leaking".

Again nothing really was changed from 1st to 2nd dyno session except catch-can. I did notice on the A-tap that the SLP 85MM MAF did not get the same "air flow" as the first session. The A/F on the dyno showed 13.1 - 13.5. The A-tap showed .915-.950. A-tap and dyno A/F usually show both either lean or rich. But not this time.

Now (finally) the question???? What could the problem be? Vaccum leak some where? MAF dead? I have a new MAF on order. For some reason is the cath-can the problem (I have checked and re-checked the fittings and PCV position). The SS seems to be running just fine. Just low on HP.

I have the entire bolt-on stuff. All mods are at my shitty web-site.

HELP

David

plumbr

I'd start with a leak down test, make sure the compression is there. Check the simple stuff plugs, wires etc..... Good luck keep us informed

SSEUL8R

sounds like your tuner may have totally screwed up

Navy David SS

iTrader: (13)

Thanks for the replies

What could have changed setting in the drive-way that a leak down would be needed? After the 1st dyno (with no problems pulling 413rwph) the SS basically sat in the drive way, with only a few start up. Spark-plugs fouling - wouldn't this give me some type of miss? None off all the runs.

My tuner is one of the best on this board. Not that. (I also put back in the original untouched program that I ran for the 413rwph pulls).

What would happen if their was a vaccum leak? If the MAF just decided to stop working right? I just completely re-connected the catch-can; have a new MAF arriving on Tuesday. Sh*t,

Help!!!

David

Scalpel

iTrader: (4)

Nothing was changed on the car so I doubt you have a vacuum leak.

I assume you dyno'd on the same dyno as before?

Navy David SS

iTrader: (13)

Yep. Almost same weather conditions. -- The only reason on the vacuum leak would be - DID I Screw-up on the catch-can - don't see how but who knows .

Thanks

David

gomer

iTrader: (13)

I run a catch can on my car and it didn't hurt my dyno numbers any what so ever. I really think you should get a stock MAF from someone and try that on your car. Ask Jason at TSP what he thinks about the 85mm MAF's I seem to recall him throwing one in the garbage

Scalpel

iTrader: (4)

I seriously doubt that it's your problem. Even if you left the PCV disconnected you wouldn't lose near 40 RWHP.

I doubt it's the MAF either.

Navy David SS

iTrader: (13)

Thanks guy. But something is robbing me of the HP ??????

Gomer/Cannibal - what MAF are you guys running? I have "read" that the stock MAF can handle up to 450 rwph. I have a wet TNT nitrous system. On a small 100 shot it is over 500 rwhp. Would the stock MAF still be OK? -- I do have my stock one laying around.

Thanks

David

Jason99T/A

iTrader: (21)

I would do a leak down on the motor, just to see if possibly the valvejob went away,etc. Was the power down everywhere?

Jason

gomer

iTrader: (13)

I'm running a stock MAF with the screens out. I had a stock ported MAF on, but Jason from TSP made me take it off and replace it with a stock descreened unit. That REALLY helped the midrange power of it and fixed the driveablity issues I had. Stick the stocker on, that would be the cheapest thing to try.

Jason99T/A

iTrader: (21)

I also agree... stock MAF is plenty for 99.9% of the setups out there.

Navy David SS

iTrader: (13)

Jason99T/A -- I'll have that done since a couple of guys suggested it. But what would have done that just setting the drive-way?

Gomer - I'll break out the stock MAF.

I'll head back to the dyno with a handful of suggestion and possible solutions.

This whole thing makes no sense.

david

Jason99T/A

iTrader: (21)

David, how many miles did you put on the car between dyno sessions? I do agree, that is very weird if there were hardly any miles put on the car.

Does your car smoke at all on start-up?

Jason

gomer

iTrader: (13)

Keep us updated, it would also pay to do a plug change.. just to be safe. I change the plugs in my car everytime I change the oil. I know that is a little crazy, but heck.. they don't cost that much. I'd stick some fresh TR6's with a .038 gap in that thing before I went back.

Navy David SS

iTrader: (13)

Jason, no real miles on the SS as it is not really streetable due to the exhaust (or lack of). The cops would really love my *** out on the street. I'd make their monthly quota in one stop.

Gomer - I have 3-4 extra brand new sets of TR6's just waiting to go in. I agree with ya on changing them often.

It really sucks to be stuck in South Dakota when most of the racers and tuners are down South - well maybe a few out East, West and in Chicago, but definately not here in South Dakota.

Thanks again guys.

David

Larry

iTrader: (4)

.915-.950 is a pretty wide span. I had the same problem until I re-torqued my intake bolts. I was getting a leak around the intake to head apparently confusing the computer and causing one bank to go way rich. Both 02s should be about the same. For some reason my bolts loosened. Yours may have done the same.

goober35

iTrader: (1)

Same Dyno???

Navy David SS

iTrader: (13)

Larry. That is one of the things I did check. My front 2 on each side were a "tad" loose. Why is it that the front ones will loosen up? This is not the 1st time that I had to re-torque the front ones -- on both the LS1 and LS6 intake. Not sure that caused the 40 hp loss but you never know.

Jason. There is no smoke what so ever on start up, letting off, or otherwise. I just changed the oil from the brake-in to Mobile 1. Went through 10-15 mild engine warm ups prior and since 1st and 2nd dyno.

Gomer. I just ran (well walked actually) to SS pulled 2 plugs on each side. All were normal I guess - light brown, no oil, no extra gas on them.

Wish they had a little man fishing for the little "smiles" you can add -- that is what I am doing - just fishing for some answers.

Thanks to everyone

David

Navy David SS

iTrader: (13)

Goober35 .. yep same dyno - almost same weather - 40's and light spratic rain..

David