New Dyno Tune

[702GT]

After finishing up my little project this past weekend, I got the car tuned today. I'm very pleased with the results, although there are a few things left in the tune that still need to be cleaned up.

Some issues that came up was the car was pulling ass-tons of timing right around 3k-3.5k rpms or so. The tuner eliminated detonation as the cause and went after the VCT as the root of the problem. He was correct. He tuned for the cam limiters at 20 degrees and the car didn't pull any timing the next pass, so he continued building on the top end, to the final result of 360rwhp/320rwtq.

The bottom end of the power band is a different story, and he's going to have to do more tuning. From idle to almost 4k/rpm the car feels like mush. Lots of stumble/hesitation and I think even backfire. We thought we had it down when I left the dyno shop, but after driving it on the street for a bit it came back. I'm also not sure where my torque went, lol. I would have thought between the 4.10's and the long tubes I would have picked up some better torque, hell even the FRPP intake manifold I figured would've done a little. But I got everything all up top, and my bottom end feels like jello. From idle to 3k/rpm's my car couldn't get out of its own way, LOL. From 4k+ it's insane. It pulls and pulls and pulls all the way to 6700. We set the limiter to 6500 though, cuz I'm a puss and still making car payments, heh. Very happy with the top end, not pleased with the bottom at all. But there's more tuning to be done.

Recently added:
FRPP Intake Manifold
GT500 TB w/BBR adapter plate
Pypes LT headers w/O/R X

Just wondering if that GT500 TB isn't hurting my bottom end more than helping. I didn't expect any worthwhile gains from it, but I didn't think it would hurt it. Not sure, we'll hafta see what comes from the next tunes.

 

[JeremyH]

Lets see...
Cams, shifts power band to the right, check
frpp manifold, shifts power band to the right, check

Nature of the beast man. Not the best cam for your setup, you could use some stiffer springs and more lift as well.

The stumbling down low is def tune related though.

 

[702GT]

Yeah, it's all part of the centri blower plan. If it wasn't for the hesitation and stumbling, I think it would be alright. Already got an email back from my tuner, we're going to hit it again friday evening.

13 more payments, then the centri build starts... I need boooooost.

 

[wht67]

Current Mods: JLT, Pypes O/R X & MMS, Comp NSR II & Limiters, Steeda CMPD, Hurst Shifter, PHP Shift Brace, VMW Catch-Can, FRPP K Springs, Dyno Tuned

Please enlighten me: why limiters with NSR cams?

 

[JeremyH]

Please enlighten me: why limiters with NSR cams?

Why ask why, really no reason to have them, they are not required.

I have vsr cams and installed comp limiters as well even though they aren't required.

During wot the cam is never advanced more than 20 degrees anyway so i figured they cant hurt and went ahead and put them in. Maybe its less wear and tear on the cam phasers lol

 

[702GT]

Please enlighten me: why limiters with NSR cams?

MUTHA' THUMPR™ - Very rough idle, biggest cam for stock heads. Great power above 4900 rpm. Compatible with stock valve springs, benefits from converter & gears, requires cam phaser upgrade & custom tuning.

http://www.compperformancegroupstor...oduct_Code=127020&Category_Code=FRD3VCKThumpr

I didn't really understand VCT or the S197 platform very well when I first started modding the car, and I didn't have this forum or really any forum as a resource, and didn't know anyone with cams in their S197's. When I bought them, this is what Comp's own website says. I even called them asking why a cam that doesn't require upgraded springs would require an "upgraded" phaser. They said there have been incidents with PTV contact, and it's more of a disclaimer so people can't say "WTF comp, you never said these cams required a limiter!" I figured at the time, better safe than sorry. Besides, I got the cams and phaser limiters on sale from *gasp* rpmoutlet for $780 shipped, compared to what other vendors were offering at the time, rpmoutlet was a smokin deal. Didn't have any problems with them either, they shipped within a day or 2 and arrived a week after I ordered them in perfect condition. If I bought the cams now, I would know better. If I hadn't sold my stock cams/limiters, I would put the stock limiters back in.

It is what it is my friend.

 

[JeremyH]

MUTHA' THUMPR™ - Very rough idle, biggest cam for stock heads. Great power above 4900 rpm. Compatible with stock valve springs, benefits from converter & gears, requires cam phaser upgrade & custom tuning.

http://www.compperformancegroupstor...oduct_Code=127020&Category_Code=FRD3VCKThumpr

I didn't really understand VCT or the S197 platform very well when I first started modding the car, and I didn't have this forum or really any forum as a resource, and didn't know anyone with cams in their S197's. When I bought them, this is what Comp's own website says. I even called them asking why a cam that doesn't require upgraded springs would require an "upgraded" phaser. They said there have been incidents with PTV contact, and it's more of a disclaimer so people can't say "WTF comp, you never said these cams required a limiter!" I figured at the time, better safe than sorry. Besides, I got the cams and phaser limiters on sale from *gasp* rpmoutlet for $780 shipped, compared to what other vendors were offering at the time, rpmoutlet was a smokin deal. Didn't have any problems with them either, they shipped within a day or 2 and arrived a week after I ordered them in perfect condition. If I bought the cams now, I would know better. If I hadn't sold my stock cams/limiters, I would put the stock limiters back in.

It is what it is my friend.

Ahh, you dont have true xfi nsr cams then, you have noise makers. The agreesive lobe design to give you the lope is why they require cam phasers, you would see a nice power gain switching to an xfi stage 2 nsr cam.

 

[702GT]

Ahh, you dont have true xfi nsr cams then, you have noise makers. The agreesive lobe design to give you the lope is why they require cam phasers, you would see a nice power gain switching to an xfi stage 2 nsr cam.

Yup, but I'm not switching cams anytime soon. I like the Mutha Thumpr's, and these noise makers hurt some feelings around town lately, especially at idle

In related news, the car was back on the dyno today to attend to my bottom end issues. My tuner cleaned up the bottom end by 95% to my guesstimation. There's just one spot around 3k/rpm that has a little backfire, and while I'm very satisfied with the end results of today's session, my tuner isn't. He's very ambitious, and refuses to leave it at good enough. Brings warm and fuzzy feelings to my heart that a tuner is giving my car so much attention. My previous tuner... was less enthusiastic to trouble-shoot anything in my tune.

While we didn't make any WOT pulls, I think it's safe to say I'm putting down more than 320rwtq as of now, the difference between wednesday and today is night and day. Drivability was all he was focused on today, and that, as I said, is 95% perfect. He's making some calls monday to find out more information on why he's having such a hard time getting that 3k/rpm range dialed in. He had to pump a shit-ton of timing into the low-end to get it to not backfire and hesitate. We're talking 33 degrees of timing at 3k/rpm and non-WOT. We were thinking that perhaps the Phaser Limiters were not installed correctly, but those limiters have been in the car for over a year and a half with 0 issues. It wasn't until the recent additions went on that my bottom end took a dump. Apparently, without the CMP's, and with all the added airflow that's opened up, I need assloads more timing to drive the car under normal conditions. At WOT, it's not an issue. Is it possible to have incorrectly installed Phaser Limiters and not know it? I remember doing them myself, they aren't exactly a complicated piece of hardware lol. It'll be interesting to see what he digs up. He wants to add more timing to that specific rpm range to see if it rids the bottom end of that backfire all together, but he doesn't think that much timing should be neccessary, since I'm already over 30 degrees of timing. For now, the car is running great under normal and WOT conditions, but he's determined to dial it in 100%. Love that guy's ambition. It's rare.

 

[JeremyH]

You would throw a code if something was installed wrong on the phaser.

Looks like he is taking care of it!

 

[cdutchess78]

just to let you know. i installed a bbk throttle body,followed by,cams,followed by frrp manifold.i had it dynoed after cam install and then after manifold.it picked up hp every time but actually dropped 5 on torque when i installed the manifold.along with that, i was able to go to a different tuner and use their dyno and when i did that the guy removed my throttle body as i was having some idle issues.that cleared it right up and netted me 2 hp.lol.

 

[702GT]

just to let you know. i installed a bbk throttle body,followed by,cams,followed by frrp manifold.i had it dynoed after cam install and then after manifold.it picked up hp every time but actually dropped 5 on torque when i installed the manifold.along with that, i was able to go to a different tuner and use their dyno and when i did that the guy removed my throttle body as i was having some idle issues.that cleared it right up and netted me 2 hp.lol.

Car idles and drives normal now, plus I have low-end like I never had before. There's just 1 spot in the 3k/rpm range that's buggin, and he's all over it.

 

[cdutchess78]

good to hear man!

 

[3vs197]

had it dynoed after cam install and then after manifold

what was the before and after numbers with the manifold?

 

[deputyperk]

i say that combo of frpp manifold and catless lt might be helping with lack of low end

 

[702GT]

i say that combo of frpp manifold and catless lt might be helping with lack of low end

As I stated later in the thread, my tuner has been fine-tuning everything under 4k/rpm, including partial throttle issues. As of the latest tune today, the car is damn near perfect all the way around, and way more low-end than I was expecting him to recover. After the final tune is cut, I'm going to get another dyno pass in just to see what the final result was in torque gains compared to the 320 I started off with. I should have E/T numbers before then.