Low numbers?? I think its the converter???

**02Sweet** · 08-09-2010, 05:02 PM

Car is a 2002 Z28
Mods:
Ebay headers
3" duals, xpipe, 1 chamber cherry bombs
Edelbrock Pro Flo XT
90 MM TB
85mm gm maf
241 heads
242 244-610 612 112 lsa
Yank PT4000
3.42 10 bolt

What do you guys thing final numbers were
347 HP
302 TQ

**LSXZ28** · 08-11-2010, 04:31 PM

I would say that converter isn't gonna make big numbers... but I would question the tuning because of the power going down from 5700 to 6200 and then back up again. If it isn't in the tune, something is making it lose power there... And why was the run cut off before it even peaked? That cam was still makin power...

**Mr. Luos** · 08-11-2010, 05:15 PM

What was the A/F?

My first thought looking at the graph is the tune as well.

**02Sweet** · 08-11-2010, 05:47 PM

I don't know about the tune but while driving my wideband goes from 12-14 range.

I emailed yank and they asked me to break stall it. I told them I got to 3800 rpms before the tires went. There reply was its acting like a 4800 or higher. No matter what I have to start there.

About the drop off in rpms I asked him not to spin it any higher after I saw the low hp numbers.

**AKA Speedy** · 08-12-2010, 08:18 AM

Originally Posted by 02Sweet

I don't know about the tune but while driving my wideband goes from 12-14 range.

I emailed yank and they asked me to break stall it. I told them I got to 3800 rpms before the tires went. There reply was its acting like a 4800 or higher. No matter what I have to start there.

About the drop off in rpms I asked him not to spin it any higher after I saw the low hp numbers.

I would assume with your cam and TB you should be putting down more. Its gotta be the tune.

I have patriot stage 1.5 heads, a 224/224 .563/.563 114 LSA Cam, factory TB, Flowtech LT's, factory stall, 2.5 in. TD's w/ flowmaster super 44's and I put down 370 rwhp.

...On a DYNOJET

**m1a2d3** · 08-13-2010, 02:57 AM

was the converter looked ? 4000 thats a big stall if its a daily driver. numbers seem a little low.

**02Sweet** · 08-13-2010, 04:23 AM

Originally Posted by m1a2d3

was the converter looked ? 4000 thats a big stall if its a daily driver. numbers seem a little low.

d/d?

I could d/d but I wouldn't want too. That is what my magical VTAC!!! is for.

My thing is where the graph starts. The rpms seem way too high

**allbaugh_04** · 08-13-2010, 04:33 AM

Ok those are REALLY low. Almost what I made on a mustang dyno and I don't have nearly the mods you do.

I'm not liking the graph either.

Is this locked or unlocked? Either something is wrong or some bad tuning.

How does the car actually feel driving WOT?

It is 92 degrees but it shouldn't make THAT big of a difference.

**02Sweet** · 08-13-2010, 04:55 AM

Originally Posted by allbaugh_04

Ok those are REALLY low. Almost what I made on a mustang dyno and I don't have nearly the mods you do.

I'm not liking the graph either.

Is this locked or unlocked? Either something is wrong or some bad tuning.

How does the car actually feel driving WOT?

It is 92 degrees but it shouldn't make THAT big of a difference.

Converter was unlocked. Car pulls under WOT but Doesn't feel strong to me. The converter feels like its slipping 3500+ to go up a small hill.

**allbaugh_04** · 08-13-2010, 10:07 AM

Maybe your transmission is slipping.

My buddy has the same converter as you and put down 380rwhp locked. Cam, intake, headers exhaust.

His transmission was slipping and put down like 350rwhp. Got a performabuilt and got 380+

**Hi-Po** · 08-13-2010, 10:20 AM

At 5700 RPM's the power actually drops, and then rises again. That doesnt make sense.

Tune.

**Frost** · 08-14-2010, 05:32 PM

that's unlocked, so it hurts numbers. Why not locked for tuning?

Everyone jumping on the tuning wagon is always common, and the majority of the time it's in the setup. As was said, that big cam was still making power...

**LSXZ28** · 08-14-2010, 05:53 PM

I agree that it very well could be the setup. The biggest reason I said possibly the tune - look at the graph - the really horrible looking first pull was made to over 6k rpm... what kind of tuner pulls a car that is off that much to over 6k rpm? I know that by the time I get that high, the tune is nearly on...

**Frost** · 08-14-2010, 07:42 PM

If you look at the numbers, it almost looks like a dead/misfiring cylinder

347 HP
302 TQ

If you take those numbers and divide by 7 and then multiplying by 8 (to see what would be if this were the case):

396.6 HP
345.1 TQ

Just speculation.

**02Sweet** · 08-15-2010, 04:58 PM

Originally Posted by Frost

If you look at the numbers, it almost looks like a dead/misfiring cylinder

347 HP
302 TQ

If you take those numbers and divide by 7 and then multiplying by 8 (to see what would be if this were the case):

396.6 HP
345.1 TQ

Just speculation.

Makes sense to me frost. I have no idea but I do know the converter is slipping like crazy right now.

About the misfire part. That makes me wonder I have never had the flashing ses light.

About the combo some people have said. What are your thoughts to tweak/change/upgrade? I am curious to see what others have to say.

**0rion** · 08-15-2010, 05:58 PM

I agree that your numbers aren't great and I'd like to see what the AFR was on the dyno pulls but look at what your chart was doing when he let out of it at the end.....it was still climbing. That big ole cam is gonna want to be spun real hard to make numbers. One of the reasons I'm not a big fan of those huge cams.....just not practical for anywhere except the drag strip and being spun to 7000+ rpms.

**02Sweet** · 08-16-2010, 02:11 AM

Originally Posted by 0rion

I agree that your numbers aren't great and I'd like to see what the AFR was on the dyno pulls but look at what your chart was doing when he let out of it at the end.....it was still climbing. That big ole cam is gonna want to be spun real hard to make numbers. One of the reasons I'm not a big fan of those huge cams.....just not practical for anywhere except the drag strip and being spun to 7000+ rpms.

Yeah the cam loves the high r's. That is where I want most of my power.

**Frost** · 08-16-2010, 01:04 PM

Originally Posted by 02Sweet

Makes sense to me frost. I have no idea but I do know the converter is slipping like crazy right now.

About the misfire part. That makes me wonder I have never had the flashing ses light.

About the combo some people have said. What are your thoughts to tweak/change/upgrade? I am curious to see what others have to say.

All of your misfire tables should be totally disabled with that setup.

As soon as the OEM converter and cam left, so did any type of reliable PCM misfire detection. Your tuner should know if that was the case though (a misfiring cylinder I mean).

**02Sweet** · 08-16-2010, 04:13 PM

Originally Posted by Frost

All of your misfire tables should be totally disabled with that setup.

As soon as the OEM converter and cam left, so did any type of reliable PCM misfire detection. Your tuner should know if that was the case though (a misfiring cylinder I mean).

I emailed him and he confirmed there was no signs of a misfire. I am shipping the converter out tomorrow to Yank to get a freshup. I should know if that is the problem soon

On a side note is there anything I should upgrade/replace while I have the trans out that I probably forgot.