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Peter Guldan Peter Guldan is offline
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Join Date: Apr 2004
Location: Memphis
Posts: 130
Howdy Juice,

Just back myself from latitude 12degrees 10 minutes N myself (still trying to figure out how someone could fully exercise a PWR EFI 930 on Curacao) but anywho, long winded response/clarification forthwith....

Can make no claims on their accomplishments. As you'll note under the Pat Williams Racing Homepage link at my site in the sig below, I don’t work for PWR (to rigorous a work schedule for me this late in my career), rather, Pat and I are very good longtime friends, I do all his website/content and am at his shop regularly. With that, let me answer to pm’s in a similar vein with the following: This complete shop access, 32 years of driving/working on 911/930’s and 20 years of doing high end restorations on machines well into the realm of “collectability” and far beyond the level 911 turbo’s may ever achieve gives one a different perspective that I hope may benefit the younger enthusiasts here and is thus my sole objective for being on this board.

We all own a machine that can be hugely expensive to restore/modify that’s worth relatively little at the end so lacking high resale to justify pain encountered along the way, what’s left is essentially entertainment value. Some fulfill that entertainment value with long term projects and I’m with them on that, this machine meandered over a 12 year period to completion, so in good conscience, I can’t/don’t post on those … but would hope they ‘d limit any collateral engine damage along the way as our quality original parts are increasingly NLA.

On the other hand, for the chap who simply wants to get the best “bang” (figuratively, not literally) for his buck as quickly as possible and to then just get in and drive, be it track or street, the above referenced exposure/experience may provide some benefit to someone in his 20’s/30’s for which pulling the trigger on a low/mid five figure check is a sacrifice he’d like to endure one time and not in multiples in “hopes” of getting it right at some point. And that’s where my unbridled enthusiasm comes in for what PWR”s doing and thus any posts related to the topics y’all are discussing. For all athletes, there’s a point where the pontificating ends and the rubber meets the road and it couldn’t be more demonstrative in our case: PCA endurance racing. Positively the best affirmation your stuff works and will last, the latter an absolute mantra for PWR as best exemplified by the 3.4 TT GT 1 that won Daytona Oktoberfest on its original season and a half motor with over 60 race hours on it!


OK, nuff of that. Earlier question regarding a Carrera manifold vs ITB’s: PWR built and campaigned 2 identical 2.61 TT’s in GT 3 in 07, this one with a Carrera manifold (CM) and one with ITB’s. Hours of dyno and year’s racing provided valuable data. Though a Carrera (CM) manifold provided all the head room necessary on the 2.1TT, with somewhat similar torque build as ITB’s it ran into a wall at 7,100 at this displacement leaving about 9k on the table - so vital to making a small performance indexed motor competitive. Actually this ceiling was not a bad thing, the H&R boys objective was to be a rule changer for PCA (achieved), they set the all time PCA track record at VIR for any class and this high end power trail off actually worked as a subtle governor because as you can see here at Mid Ohio, they absolutely take no prisoners on the track with those touching red bars on the AIM meaning redline exceeded. That driving style would never work with ITB’s; they become such an unbridled accelerometer at high rev’s compared to a CM, you’re at rocker breaking rev’s almost before you can shift. So, when PCA changed the rules bumping them to GT 2, mindful of this manifold’s difficulty with high velocity gas management, PWR built them a 3.0 TT to fatten the low end torque curve and they picked up right where they left off as anyone who was at Road Atlanta in April saw.

To close out the subject, as ITB users know, 6 shaft/linkage setups are preferred for accuracy/longevity but they are very spendy. PMO has developed a very nice reasonably priced set of twin common shaft manifolds for EFI use here. Here’s a pic while it was being wired/plumbed up and a distributor built to suit a ref signal pickup. Pat’s completed his first speed/density map for this set on a 2.7litre NA motor and now begun an alph/N map on the same setup to suit pressure-differential challenged overlapped cam motors that can’t provide enough resolution for a good open loop street motor map. I’ll post some more pics/video soon. With some light mod’s, these might provide a more economical starting point for a street oriented turbo motor.


__________________
Cheerio,
Peter

1950 Vincent Rapide - A Red Rapide Experience -
Old 01-14-2010, 11:41 AM
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