From:Tim Roller>magnum318@bewellnet.com
>Great update on the Holloway "Super " TB, and I commend you on such great
weather and testing conditions and the testing results. I feel I can't
recommend any feedback, because I don't know what you have done to the
engine as aftermarket parts or is it just stock, and only the 2 TB's used as
a testing procedure. From what I can see, if your truck motor is basically
stock and only maybe headers, and exhaust work done, the reworked stock TB
would fill in the needs for most of us. If you have extensive
valve-train(1.7's), cam, headers, Jet or Mopar Performance Computer firing
the injectors then from what I see is a serious lean condition on the upper
end of the mid-range to the rev limiter and maybe a new mapping of the
computer module is in order to take care of this to prolong the injector
discharge or just a more agressive injectors--maybe around 22 or 24 Pounds
per Hr. That 700 cfm is overkill for a mild stock engine--just like putting
on a bigger carburator. Looks good, but it's not necessary and performance
will be seriously affected.
-----Original Message-----
From: Bridges, Bruce <bbridges@alarismed.com>
To: 'dakota-truck@buffnet.net' <dakota-truck@buffnet.net>
Date: Monday, October 05, 1998 11:44 AM
Subject: DML: R/T Big throttle body track testing (loong)
>DML,
>I tried out the 700+cfm Holloway stage II throttle body at the track
>Saturday. Got some interesting results. The conditions: 75deg F, 70%
>humidity, 29.99 Atmospheric pressure.
>
>I started with the Stage I TB (see pics on the DML) this TB has stock
>butterflys was unshrouded and "cleaned up". disconnected the battery for 5
>min, reconnected and lined up: (note final mph are off due to track
>"problems"...
>Run 1, Stage 1 TB:
> R/T .628
>60ft: 2.319
>330ft: 6.395
>1/8ET: 9.801
>1/8 mph: 71.69
>1/4 ET: 15.32
>Mph 89.87
>Run2, Stage 1 TB:
> R/T .833
>60ft: 2.216
>330ft: 6.282
>1/8ET: 9.684
>1/8mph: 71.74
>1/4 ET: 15.209
>Mph 89.72
>all runs: transmission in drive. ended the test of the stage I since the
>track was getting crowded and the Big TB was calling my name!
>Run 3: Stage 2 TB
> R/T .617
>60ft: 2.304 (lots of tire spin)
>330ft: 6.404
>1/8ET: 9.832
>1/8 mph: 71.19
>1/4 ET: 15.409
>Mph 88.89
>Run4: Stage 2 TB
> R/T .759
>60ft: 2.275
>330ft: 6.362
>1/8ET: 9.781
>1/4 ET: 15.348
>Mph 89.04
>Run5 Stage 2 TB:
> R/T .753
>60ft: 2.302
>330ft: 6.379
>1/8ET: 9.782
>1/8mph: 71.77
>1/4 ET: 15.305
>Mph 89.77
>Run6 Stage 2 TB, Manually shifted
>R/T .674
>60ft: 2.213
>330ft: 6.363
>1/8ET: 9.817 (hit the rev limiter 2-3shift, ouch)
>1/8mph: 70.83
>1/4ET: 15.410
>1/4 Mph: 88.92
> hit the rev limiter on 2-3shift (manually) kinda slowed me down...hits
like
>a ton of bricks.
>Note the run6 60 ft time vs the run 2 60ft time. Extra wheel spin and
still
>the same time!!!
>My impressions:
>The R/T loved the Stage I TB combined with the exhaust mods and JETII
>module. It felt like it would go faster as the computer "caught on" to the
>combo. A great combo for the street cruiser thats wants snappier
>performance from their R/T for minimum bucks. I think my combo of mods has
>scrubbed around .5-.6 seconds in E/T from the stock config. The Stage II
>TB presents some mysteries/opportunities. On the track, it felt "softer"
in
>the mid range but pulled hard to redline after about 2500rpms. I had a
>significant problem with traction with the stage II TB as well but not with
>the stage I BUT my 60ft times (2.216 stageI vs. 2.213 stageII are
>equivalent! More grunt at the botom from the bigger TB, go figure?). Its
>hard to tell about the traction problem since the track had "aged" over the
>afternoon and probably had gotten more slippery since the first run. I
>didnt see the 14s I was hoping for, nor huge improvements from the big
TB...
>BUT On the drive home, I noticed a definite surge at WOT at freeway+
speeds.
>I continued driving putting about 2 more drivecycles on the truck. At that
>point I felt that I am getting to 90mph from 65 mph faster than ever, but
>after "extended" WOT at 3K + rpm I get the surge. This says to me that Im
>too lean at the top end. The R/T never surged with the stage I TB. Hmmm
>Frank suggested removing the JET chip to see if the WOT gets better. Ill
do
>that this afternoon. Sounds like more mods are needed... New comp mapping?
>Bigger injectors? Ill keep the list posted on what those might be as we
>get further along in the development process... Any suggestions to make
the
>big TB work?
>BKB
>
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