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Scott Kelly's Website comments

Thanks for all your comments Scott. Thanks for taking to the time to help us and answering questions.

On our exhaust thread, the stock elbow is the biggest restriction. I was going to reply to save the money for a nice 3" downpipe.lol Most of us have them but are only made by one gentlemen for the public now. I noticed a big difference when I installed mine. Performance, spool up and response was added for sure.

On these cars, I have learned to free up the restrictions... and little by little they all add up!

Thanks for all your comments Scott. Good luck with your project!

Joe
 
Hi Guys,
Sorry for not getting back sooner but the project Viper has burned up more of my time than I was expecting.
First let me respond to the recent PMs.
Jan,
On the TTA Registry I would recommend a format similar to the registry for my Ferrari GTE. They publish a registry and a quarterly newsletter for $40 per year. The registry goes by serial number and keeps track of any time the car was for sale, attended and event, has any special features, and the name and state of the current owner. This may be a lot of work for the 1555 cars but would help build the heritage of the cars. The newsletter has more of things like articles on famous owners, coverage of events that the cars participated in, arrangements for events like TTA dinners at events like the Woodward dream cruise.
michbc3,
On Diffs, the diff will hold up fine for a stock car with street tires. For over 500 lbs ft of torque I would change to a Dana 44 LSD. We used these in the TTA HO and the Twin Turbo to get them to live. I also slipped the diff clutches with one of the test TTAs at the drag strip while launching at 3 lbs boost with slicks.
All of these cars should have their fluid changed by now and I personally use M1 synthetic in everything.
On Fuel Systems, you are in the right direction, determine the target then design the system with the formula. Build in about 15-20% extra capacity to be same on boost spikes.
On Meth Injection, I just removed an Alchycontrol system from the Viper I am working on and it looks like a good system, however the installation was poor in this case and the car will only be using about 7.5 psi. Also, this car is not drag raced.
On your modifications, with the power you will be making please consider 1) a six point roll cage to increase torsional rigidity when launching 2) a driveshaft safety loop 3) Dana 44 LSD 4) a stronger driveshaft and u-joints.
My last comment…..Do you really want to modify this car to this extent or leave it stock and by a faster, durability tested, engineered car like a Viper or Z-06?
The PAS Inc. Website,
I added a section for the TTA HO and TTA Tidbits on to the site. I will also be starting to work on the Syclone side of things soon.
Here are a couple photos of the Viper engine. The owner was embarrassed at every event since the car would die often and be trailered home. What I found was what typically happens to a nice guy that wants a custom car that gets talked into “upgrades” by someone who reads too many magazines. I will post before and after photos on the site under current projects soon. This car has had 3 engines in it with 33k miles. After breaking the engine the second time, the “mechanic” talked the owner into putting a newer engine in the car. In order to put this engine in he proceeded to hack the car up to make parts fit. We have 240 hours and $11,000 in parts to get it correct so far. If that wasn’t enough, the “mechanic” also bored and stroked the 8.3 liter engine to 9.0 liters along with a Paxton supercharger. The boost was low because the pulley ratios were incorrect to get 9 liters of air at 7.5 psi into the engine. We have redesigned the entire fuel system, ignition system and reworked the supercharger system along with Paxton. I now need to reprogram the ECU (AEM) to run correctly now which should take another 100 hours.
There is so much work in this car to make it safe and reliable that I am now part owner of it to save the owner a massive bill.
On Rich VanToff’s cars, the convertible is as it was the last time I drove it. The black emissions car was in bad shape when Rich got it and it needed the restoration it was given. The burgundy car was in good shape when it was sold from PAS but I cannot vouch for it since. Just as the antique Ferraris I work on as a hobby, whether you want to or not, most cars must be restored after 20 years so I am ok with what Rich has done with the cars.
On the engines, we at Prototype Automotive did both engines. They are called “display engines” and the brochure engine was used for just the brochure. We had to build in a hurry due to a tight timeline for the photo shoot. It is actually one of the 20k durability engines that was in either the black or the other flame red car. The coated tube and turbo cover are aluminum sprayed and Greg Palm and I had samples made to see if there were any benefits. They looked the best so they ended up on the brochure engine. The second “cutaway” display engine was used at the Detroit, Chicago and other auto shows and some of the emblems were left over samples. Look closely at them next time you see a photo.
For the record, there are only 3 original test cars left. The black one Rich has and the flame red one that a friend owns (ex prototype employee) were used for Durability and emissions use among other things.
The flame red one that Rich owns with the digital dash was called the “Shop Queen” and was owned by Triad/PAS. That car stayed at the Triad shop in Troy, MI and was used ONLY to fit prototype parts and production samples to verify dimensional accuracy. I modified the harness to fit the 3.8 Turbo. For those who care, I met my Wife under the hood of this car as she wrote the Owner’s Manual Supplement for your cars! Unfortunately she was told to use this car for making line drawings and it was not accurate for that at the time. Because of the crazy hours I was working the only time I could meet her to work on the manual was on a Sunday. We finished the final review on the way to the Columbus Ohio IMSA race where Prototype had several Trans Am entered. We won first and second in that race. I will cover more of that on the website as well.
Have a good day and I will try to get more up on the site soon. I am going forward with recreating PAS at this point and am planning to have a facility in the second quarter of next year.
Scott
Viper Engine
 
Jan,
On the TTA Registry I would recommend a format similar to the registry for my Ferrari GTE. They publish a registry and a quarterly newsletter for $40 per year. The registry goes by serial number and keeps track of any time the car was for sale, attended and event, has any special features, and the name and state of the current owner. This may be a lot of work for the 1555 cars but would help build the heritage of the cars. The newsletter has more of things like articles on famous owners, coverage of events that the cars participated in, arrangements for events like TTA dinners at events like the Woodward dream cruise.

Scott, once I got the list of information from you to work from I'll have to see what's doable given time and resources. I still like to do this but provide more value to all of us in the end per my PM.

Best Regards,

Jan
 
Posted by PAS1: "My last comment…..Do you really want to modify this car to this extent or leave it stock and buy a faster, durability tested, engineered car like a Viper or Z-06?"

Hi Scott - I think that I have the right car for my purposes: 99% street, 1% dragstrip (to gather data on my modifications). My TTA is already modified to a large extent. I believe that eventually I should have no problem matching or beating a factory stock Viper or Z-06 Vette in a straight line - and maybe even some of the modified ones. I have no road racing ambition. So with a $20K investment, lots of study, strong parts, wrenching and experience, I hope to have some fun knocking off a few $100K car owners whose comprehensive technical knowledge can typically be summed up as "getting a big fat bank loan". Some see it as the American way for the common man to use his ingenuity to knock a Prince off of his high horse every once in a while.
 
Along those same lines, my car was purchased for $4500, didn't run, and needed(needs) restoration beyond anyone's ability to making it concorse worthy. So, yes I'm going to modify it.

In my opinion, unless it's stored in a museum, it's not doing anyone any good if it's not being driven.
 
PAS1 wrote: "On your modifications, with the power you will be making please consider 1) a six point roll cage to increase torsional rigidity when launching 2) a driveshaft safety loop 3) Dana 44 LSD 4) a stronger driveshaft and u-joints.

Hi Scott - Noted. Although I'm pretty good with engines, I know very little about differentials. So I'm going to need some help.

Are you saying that a Dana 44 LSD carrier would fit inside the factory TTA housing? If not, does somebody make a new Dana 44 setup that would be a "bolt in" on a TTA? I know that some of the Firehawks came with the 44, but obviously finding a used one in good shape would be a needle in a hay stack since any modified Firebird owner would want one.

Though my existing 200-4R was beefed up by the previous owner of my car, I'm going to have another transmission purpose-built. There's a good racing transmission guy in Flint, MI that I know. So I'll be browsing the junkyards next summer to try to locate a good case.

Bob
 
Along those same lines, my car was purchased for $4500, didn't run, and needed(needs) restoration beyond anyone's ability to making it concorse worthy. So, yes I'm going to modify it.

In my opinion, unless it's stored in a museum, it's not doing anyone any good if it's not being driven.

TTA579/Scott - Do you have to pass emissions out there? Perhaps you're not putting it on the street. Here in VA I have to pass emissions ONE more time this coming April, then I'll be exempt from further testing. I've passed before and my engine is now in better shape than ever, so I'm pretty confident that I'll make it. If for some reason it doesn't pass, I can always store it for 2 years (not in a museum of course) and mess around with my old Corvette for a change. :yes: Don't get the wrong idea. It's not a $100K car...
 
Strange Engineering offers a "bolt in" Dana 44 for F-body cars. It requires a slightly shorter drive shaft.

For transmissions there are a number of performance 200R4 transmission people. CPT Transmissions here in California looks promising.

Yes, I have to pass emissions, which I haven't (too much unspent fuel, and an EVAP leak). I understand the point in storing a car, things come up, life happens. Not driving a car simply because it is special however, I disagree with that concept.

There's a museum here in LA, the Automotive Driving Museum, and all the exhibits are working models, and they offer rides on Sundays. My kind of museum.
 
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Strange Engineering offers a "bolt in" Dana 44 for F-body cars. It requires a slightly shorter drive shaft.

TNX! A few questions that you might know: Will our TTA brakes fit on it? Does it have the right bracketry for the track bar and torque arm? Can I get a 3.27 gear? I figured that a stronger custom driveshaft was in my future anyway so that's not an issue.

Bob
 
I don't know the specifics about Strange's products. I've wondered about the brakes and wheel offsets myself.

Moser and Currie also build rear ends that can be used on 3rd gen F-bodies, but I know less about them.
 
I didn't see any Dana 44's on Strange's website - only Dana 60's. Edit - I just checked, and the Dana 44 for sale is sold already.
 
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You're right, my mistake. I don't know the difference between the 60 and the 44.

I'll be inquiring about the Strange 12-bolt myself.
 
I went with a bolt in strange 9 inch with 32 spline axles an tru lock diff with 3.55 gears hth with a custom dennys drive shaft
 
I have a strange Dana 60 it works great and easy install. I got the brake package so I didn't have to mess with all that.
 
I don't know the difference between the 60 and the 44.

Dana 44 has 8.5" ring gear and the Dana S60 is 9.75" ring gear. where the 44 is weaker is the pinion diameter.The Dana 60 is probably the toughest aftermarket rear end for the 3rd and 4th gen cars. But it has it's drawbacks, much like the Ford 9" it is a bit of a H.P. hog and heavier.

But if you're making big H.P. who cares?
 
I have a Dana 44 from one of the firehawk race teams. It was a backup rear and just made a few laps to test it. Its in my 92 Formula Firehawk clone.
I have a moser aluminum center chunk 9" ford in my 89 Formula 350. Its loud, gears whine, leaks and it vibrates (put stock rear in and it goes away) but it sees major abuse so I deal with it.

The dana 60 takes 13rwhp more than the ford 9" and the 9" takes 3-4 rwhp more than a stock 7.5-7.625 10bolt in 3rd gen cars.
GM High Tech did a story on them a few years ago. My numbers may be off a bit but I was suprised about the ford not being that bad and the Dana sucking the most power.

I also would like some info on the Dana LSD in the 9bolt housing. I highly doubt it would work but if it did there would be a lot of jeeps without diff guts !!
 
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My understanding of the Ford vs. the dana 60 comparison is that your numbers are reversed. Because of the 9" pinion engaging lower on the ring gear than the Dana it is more of a horspower hog. And I think I read about this on Strange engineering's website and it was compared to GM's 12 bolt.

What I'd really like to see is somebody start making a 3rd/4th gen axle using Ford 8.8 center section.
 
Nope, I used to believe the Ford pinion myth also. Now a 9" over a stock rear, yes it takes more power but 3-5rwhp isnt bad compaired to the dana60. That DANA 60 is a freakin' monster. I guess I need to test my Dana 44 !!!
I'm with ya on the 8.8 rear. A few guys have even done it.
Yes my original numbers are a bit off but here is the test GM Hightech did.

Full story.
http://www.gmhightechperformance.com/tech/0804gmhtp_strange_s60_moser_m9_rearends/viewall.html

Comparative Results
So far, we've discussed numerous differences between the two packages featured in this story (one of them being the state of completion each axle assembly is shipped in). But we also decided to do a bit more detective work to compare and contrast the two kits even further. Though by no means an apples-to-apples comparison-remember, each of these companies offers several different rear-axle assembly packages compatible with 4th-gen F-bodies-we'd like to give you, the readers, as much information as possible in hopes of steering you in the direction of the "right" axle assembly for your application.​

First off, there is the issue of mass. Though aftermarket axle assemblies are far stronger than the F-body's stock 10-bolt, the added meat required to support this strength does incur a weight penalty. More weight to drag around means reduced acceleration; plus, an axle assembly is unsprung weight, so a more massive one will affect suspension behavior. With that in mind, we decided to weigh the stock rear and compare it to the Strange and Moser units. With all rears at the same stage of assembly-no brakes and no fluid, torque arm variations not factored in-the breakdown is as follows (keep in mind that these are dry weights, so differing fluid capacities can factor in to actual running weight):​


TABLE OF REAR-AXLE ASSEMBLY WEIGHTS:
Rear Dry WeightChange from
StockGM 10-bolt....154.6 lb-
Strange S60 .........222.8 lb+68.2 lb
Moser M9..............205.6 lb+51.0 lb A aluminum center chunk will free up 20-30lbs and a spool a bit more.​

Secondly, one thing you may not think of with regard to added mass is that it can also come into play in power loss. More massive axles and gears require more energy to get up to speed, adversely affecting rear wheel horsepower. Other factors, like internal friction, play in as well, of course. This friction may be attributable to bearing properties, along with axle fluid viscosity and flow behavior, and can also be influenced by geometric concerns like the diameter of the ring gear (which is intertwined with the properties of how the ring-and-pinion mesh). Though the physics involved may merit a full-blown engineering discussion in a future issue, for now we decided to do before-and-after testing of both of these project cars on TTP's Dynojet for a quick comparison. Our results are:​


TABLE OF REAR-WHEEL HORSEPOWER/TORQUE CHANGES:
Car Rear Old HP/TQ RearNew HP/TQ%
LossJensen Camaro Stock...3.42...412.5/390.0
Strange S60 ....................3.73...397.9/376.0 3.5/3.6%loss
Werner Trans Am Stock......3.42...441.2/432.3
Moser M9.........................3.70...436.6/428.6 1.0/0.9%loss​

We're quoting the new and old axle ratios because a numerically higher rear-axle ratio necessarily reduces measured rear wheel horsepower on a dynamometer (again, for reasons that would best be described in a no-holds-barred engineering analysis). But you can see that the gear ratios used in both of our new rears were virtually identical, so this factor can pretty much be taken as a constant in comparing the percent loss difference between the two axle assemblies (though before and after dynoing on different days probably should not, even with our use of SAE correction factors).​

A final note on the M9 is in order because of its fully adjustable torque arm system. Readers should be aware of what a well-constructed piece this is, and think about the fact that it was included in the price of our M9 assembly. Once installed, we adjusted this system to provide the Moser-recommended 1 degree of downward pinion angle (compared to the driveshaft angle) before hitting the dyno, and while no track testing of any sort has been done thus far, the system has performed admirably on the street, with the exception that some extra engine and road noise is now transmitted into the passenger compartment (thanks to the solid rod end connection between the torque arm and the transmission crossmember). We're confident this unit will help us put down some sick 60-foot times when the time comes to hit the strip. The system feels like it would perform admirably on a road course as well (the latter assessment is, of course, a bit subjective).​

As to his new S60, Jensen is enjoying it very much. While it needed a quick Panhard adjustment to center the rear, and does transmit some gear noise into the cockpit, he's impressed with the ease of installation and can't wait for Raceway Park to open back up to finally do some high-rpm clutch dumps!​
 
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thanks for some facts ... I hear zero noise from gears in my 9 inch ... i went 9 inch because i want to leave on a trans brake.... stock i heard alot of drive train noise hard to describe but a weird noise ? just mine ?
 
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thanks for some facts ... I hear zero noise from gears in my 9 inch ... i went 9 inch because i want to leave on a trans brake.... stock i heard alot of drive train noise hard to describe but a weird noise ? just mine ?

I have the same noise. I think it is the posi. Mine has done it since purchased.

Makes me think they were all noisy after a few miles on the road.
 
I have rodended rear control arms and they do transfer a lot of road noise into the car, which is fine. I have replaced everything (gears, bearings, diff) in my M9 with diff parts. Except the axle bearings which I have to replace with the same brand every 5-10k miles at 70 bux each. They are a junk ballbearing type made by the green bearing company for the military. They are designed to fail so they have to be replaced. Nice 4 a war vehicle huh?
I have a older 9" from moser and they have since switched their axle bearing design but I have to buy new axles to get them. I will sometime and I hope the noise and goofy problems take a hike.
 
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Hi Guys,
I finally had the Viper on the road after 450 Hours worth of work and $11,000 worth of parts. We “Unhacked” the car the best we could but did not go through the engine. I still needed to calibrate the AEM ECU and fabricate a driveshaft safety loop, front shock tower brace and install a scatter shield.
Unfortunately, it turns out that these cars have a problem with Power Steering Fluid caps that come off without warning. What happens next is that the P/S fluid sprays onto the driver’s side headers and sometimes ignites.
Well that’s what happened on Friday while the owner was taking his stepdaughter for a ride. After a blast on a local expressway they came to a stop sign on the off-ramp. The owner saw fluid on the windshield, smelled something unusual and the car started on fire. They got out of the car then the car and all the work burned to the ground.
The note I hope you guys take from this is that I had a discussion with the owner about a 900 HP car being a race car and should have all the same safety equipment. For $600 or so we could have put in a fire system (which you see on the TTA HO on the website) and saved the car and potentially their lives.
While I would rather you guys leave your cars stock (except for high milers or too far modified to restore), if you are going to modify your cars PLEASE do not get cheap on safety!
Now to the PMs:
TTOP350: The black car that you read about in that magazine (CarCraft.Sept 1989 issue page 21) was a prototype car known as Firefox. This was the first version of the car and while it was fun the second version we did was a dark green ’91 TA with a TPI 383 stoker engine with a 6 speed and a Corvette IRS. Greg Palm is now doing custom wood products and is on board to assist with the PAS projects in the future. I don’t know what happened to Greg Anderson but he ran engine Dyno’s with me and did some calibration work.
The 6-speed crossmember that you would like to have was not a firehawk part, we modified one of our stock TTA crossmembers for the Firefox, the Twin Turbo and the TTA HO. The tooling for it is long gone and GM never had it.
Also on your other PM, I don’t know who did anything with the Firehawk cars but there are several tube bending companies that will scan your stock lines and make new ones. PM michbc3 as I talked to him about making lines and he is pursuing it.
TTA579: Scott, I have put a bunch of photos of the COI building on the Website. PAS actually had 5 buildings. Thanks for your offer to take a current photo. If you have time it would be cool if you could post one on this thread. The engineering building was located in Troy, Michigan (Triad), our powertrain development building was in Farmington Hills, Michigan (Prototype Automotive Services), the TTA assembly plant was a rented building in the City of Industry, California, The Syclone assembly plant was a rented building in Shreevsport, Louisianna and finally the Typhoon, Sonoma GT and the NGV Truck were assembled in Auburn Hills, Michigan.
My business card on the landing page of the website is a scan of one from when I was at any one of three that would be at depending on what needed to be done. Crazy times!
Vetttta: Bruce, the service manual supplement for the TTA is accurate to what is on your cars as I was in charge of putting it together. Since I also designed the wiring harnesses I can assure you that someone put a resister in you coolant temp sender to simulate a lower temp to the ECM and maybe make more power. There is a diode in the fan relay circuit at the fan timer that prevents feedback from making the fans run eratically and there is a resister in the jumper harness at the map sensor to correct the accuracy of the boost gauge. If you find anything else it is not stock.
Now that the Viper is gone I will be spending more time to get pictures and stories on the website. The Syclone/Typhoon guys want their due as well. I have been in touch with the owner of the Twin Turbo Trans Am and the third prototype TTA and they are providing photos for you guys to see. I still have to go the GMs Museum to see if there are any more prototypes we built still there.
I hope you all had a great Thanksgiving and get lots of parts and tools for Christmas!
Scott
 
backSeat_89_turbo_Trans_Am.jpg
 
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