IMSA Racecar resoration:The rebirth of the Seyfert/Buist Fiero (Page 7/10) IMSA GT OCT 17, 07:41 PM quote Originally posted by Dave Deerson: The Palistini kits come with cylinders with 9 or 11in stroke. I went with the 11in as I wanted to be able to get under the car to work on it as opposed to just getting the wheels off. The kit as seen was $2200 as opposed to $5 to 7k for a "real" system from AP . The difference is in the hardware.This kit is geared toward the grassroots club racer and not someone who is going to run the 24h of Daytona or Le Mans. The fittings are the "push lock" industrial/truck airbrake type with poly tubing,not the more expensive aircraft fittings and braided steel/teflon high pressure tubing. After a full season, I can't complain about them as they have performed well so far. My only comment would be that I would have liked a larger bore cylinder so my operating pressure could be lower. I need to run around 375psi of nitrogen to lift my car with a heavier car needing more. This is just how it is even with the AP systems although there is a new company with large bore cylinders (4in I think) marketed toward Corvette guys so they can lift their car with shop line pressure( around 150psi),but I'm not sure of the name of the company. Wow, 375lbs of nitrogen. There goes the air compressor idea kwagner OCT 18, 09:48 AM Those jacks look mighty handy You say you used them a season without issues... got any (racing) video? Dave Deerson OCT 18, 09:59 AM I'd love to say I have some in car footage...but I'll get to that later. By the time I got a camera in the car at the last event(Watkins Glen), I had other issues that derailed those plans( a fault of mine that I have to get over as in the end I could have salvaged the weekend and captured some video). There's always next season.......... Dave Deerson OCT 18, 05:51 PM On to the transaxle department........ As I said before, I would love to have been able to put a Hewland DGB into the car,but ar near $15k for a trans(yes even used it's that expansive!) I just couldn"t justify the cost for the use that I really had intended the car for. So even though in comparison it's less expensive to use the 930 box, it's still way more money that I have ever had in just a transmission for any car I have built or raced. Add up the numbers......$2400 for a good used box,$1500 for a limited slip diff,$4000 for new gear ratios/dog change conversion(YES $4000 Porsche ratios are approx. $900 PER ratio), and add up the costs of HD c/v joints, special 300m alloy axles and you can see why it is very expensive to play in this arena! That is why any perceived problem from the box necessitated a teardown of it just to be absolutely certain there was no damage done. here's the box out and on the stand.... stripped down... Here is the before...Note the stock style syncros between the gears And here are the new ratios and the drive dogs on the gears and the corresponding dog rings instead instead of syncro sliders... If you look at them closely, you may be able to see the size difference between the old ratios and new with first to the right in the pic. Along with the new gears I added a trans oil pump and cooler to keep the gearbox temps in check. Last season the temps were just a little too high for my liking. The cooler I used was an ex-NASCAR EBAY deal for a nice water to oil heat exchanger that goes in the coolant line to the engine. That way the trans gets pre warmed and kept at the same temp as the engine- the best situation. So once these upgrades were on the car, off to the track we went...........To much frustration and aggravation,and a little bit of fun, each time out was 3 steps forward and 2 steps back. As one set of issues were delt with, new ones came along with the new found speed.One of the sources of returning issues were the engine mounts. Since the early planning stages of this car I had designed it around the Chevy LS series engine. The motor is light, small in external dimensions,and powerful-yet not overstressed so as to run reliably on pump gas to keep running costs in check. However, I was warned not to solid mount the engine as the non-damped vibrations would skew the signals to/from the knock sensors. So I designed the engine mounts with a very hard poly bushing. This did not work out so well in practice as even though it seemed that there was no motion from the engine on the dyno, out on track it was another story. As the drivetrain loaded and unloaded, I could feel this through the gear change lever( I use a very solid rod style shift linkage such as used on small formula cars) and it prevented me from being able to shift without the clutch. In fact at one test day, a downshift from 4th to 3rd( moving the linkage forward) coupled with the decelerating drivetrain( rotating forward also) caused both the shift fork to be forced out of adjustment on it's shift shaft and the shift pivot fork inside the trans to bend! This resulted in the trans repeatedly popping out of 3rd!! NOT something to take likely in a trans with gears as expensive as these!!!! Well, it turns out the EFI system I use had options to turn the knock sensors on or off and mine were never even enabled from the beginning! So we tuned the car with a conservative ignition map to retain the use of pump gas, fabricated solid engine mount bushings, positive shift linkage stops and had the problem solved finally. I was now able to upshift smoothly without the clutch and did not notice any negative vibrations as a result other than some extra tingling in my back as the engine revved above 6k. Next.........more on how it's not that easy to build a car from scratch and just go fast without development,refinement and seat time,seat time,seat time!!.........................did I say scratch???? Jefrysuko OCT 18, 05:59 PM quote Originally posted by Dave Deerson: did I say scratch???? You've got me cringing! kwagner NOV 13, 04:55 PM Updates? Dave Deerson NOV 13, 05:12 PM This weekend,I promise!........................I've been very busy the last few weeks with our last race weekend of the season and work at both the shop and home. kwagner NOV 14, 08:51 AM Still racing in the middle of November? Is that just because of the nice weather or is that how long the schedule normally goes? Dave Deerson NOV 17, 04:36 PM With a rare free moment, here's the latest: Yes,we race into November. Our (NASA Northeast/PDA) last event was Oct 30,31 and Nov 1 at New Jersey Motorsport Park where I brought out my old reliable Spec Miata. Alot of fun even though it was cold,rainy and dreary! But to the Fiero.......Well, nothing risked,nothing gained! Noone can accuse me of building a trailer queen,that's for sure!! as I now have scuffed her up not once, but twice!! Both times had possibilities of being complete disasters, but luckily (it was pure luck,not driving skill) only relatively minor cosmetic damage resulted. The first incident was at Pocono at the North Course where I spun off at high speed due to the throttle sticking wide open! A pebble(believe it or not) of the perfect size as any larger it would not have gotten in where it did and any smaller and it would have fallen out, got wedged in the throttle shaft and return spring on the LS1 throttle body. Thia all happened so fast, that I never processed what was going on as I went from "driving mode" to "saving mode" in the blink of an eye! As I spun off the track into the dirt/grass/rocks at high speed backwards, the front airdam got caught on the grass as the car bounced. This ripped the airdam completely off and into 3 pieces,but also took part of the left front fender with it. Escaping with only some 'glasswork to do, I wrote this off as a fluke accident. A little fiberglass, filler and paint and the car didn't look like anything had happened. So on up to Watkins Glen,my favorite track,looking forward to great weather and 3 days of on track fun. Well the second day,Sat. I overstepped my bounds a little. I must admit that up until now I have been very naive in thinking that I had a handle on this car. The reality is that the car is still very much untested and settled in that I have less than 10 full,trouble free days total on the track with . Many days were partial ones due to gremlins and new car issues. To try to think that I could hammer out fast laps at a place like the Glen with a trial setup on the car( spring/shock rates were an educated guess using notes from Jack Ondrack's Huffaker car) and limited seat time was a recipe for disaster. I am very upset with myself for not taking my normal systematic approach to stepping up the speed as I become settled into the car. I have now figured that the spring rates were way too stiff and made the car very twitchy at speed. This was not too apparent at places like Pocono,NJMP, or Monticello as they are not not as fast and flowing as the Glen. So on my 3rd or 4th lap of the 2nd session on Sat, I was coming up through the "esses" in 3rd gear at 6k rpm with is somewhere near 125-130mph, was of the line by about half a car width(no big deal really) as I came past the last flag station where the track bends to the right as it opens onto the backstretch. There is a bump there(never paid much attention to it in all my years there in slower,less horsepower cars) that if hit just right,while on the power would upset the car. With the Fiero having such as small wheelbase and very low polar-moment of inertia, this upset was all it took to get the car sideways in half a heartbeat! As it happend, I knew I was in for a ride as nothing good ever happens at that part of the track when you loose it. Cars usually pinball off the Armco from left to right,shedding parts! I locked up the tires to stop the rotation and slid backwards at well over 100mph for what seemed like forever!! I wish there was 10 feet more of grass between the track surface and the Armco,because I just couldn't scrub off enough speed before I went into it. Since I was on grass the tires stopped squealing and engine was stalled so it was quiet enough as I hit to hear the sound of fiberglass crunching and cracking!! The damage report is that again,only cosmetic, not structural damage resulted. I was VERY lucky again as I very well could have written off the car right there!! The rear of the quarter is smashed, and the rear center bumper is cracked . I do have a spare new right rear quarter panel,but it would be less work to repair this one than to remount and fit the new one. So I pulled a partial mold from the spare quarter panel to layup a repair section. The rear of the quarter panel was very crushed and most of the body lines were very lost,so a repair section was in my mind the best option. That's all I have pics for at this point,although the repair section has been grafted onto the quarter panel,roughed in and ready for primer now. I will get some up to date pics posted soon!! The last pic shows the marks from the Armco!! kwagner NOV 17, 05:07 PM Egads! Quite an eventful season.