Greetings DeLorean friends, I know this is a long post, but that's how I roll (sometimes). I wanted to let everyone know that I drove AZ-D member Dave Watts' DeLorean on Sunday, April 5, 2009 and I am writing this as a review of what I experienced. Dave had just finished reassembling his engine and installed his new exhaust system and invited me and my wife (Sam) to take it for a spin. In the six mile drive that we did, I must say that I am very impressed. Altogether, Dave Watts has modified his engine to include: ? High Performance Cam Shafts (I call them "Don's Crazy Cams") developed by Don Steger from DeLorean Motor Company - California (formerly DeLorean Motor Center) A pair of high performance racing cams which are street legal, pass smog and gives 62 more horsepower to your DeLorean when used with a header-based exhaust system. (www.dmccal.com/102707hp_high_performance_cams.html <http://www.dmccal.com/102707hp_high_performance_cams.html> ) ? DeLorean Header-Based True-Dual Performance Exhaust System from John Hervey @ Special T Auto 304 Stainless Steel Headers, Stainless connecting tubes and clamps, One piece stainless steel gasket, 12 studs with stainless steel nuts and washers, Polished stainless steel Magnaflow Turbo mufflers, and Chrome tips you can cut to length and tack on. (www.specialtauto.com/delorean-parts/delorean-parts-kits.html <http://www.specialtauto.com/delorean-parts/delorean-parts-kits.html> ) ? Some head-work including porting and polishing, valves, and valve seats by Basko Engine Service, 743 N Golden Key St, Gilbert, AZ 85233, (480) 967-1956. Don's Crazy Cams - I know from conversations with Don Steger about the dynamometer testing that he has done, that the combination of these performance cams and a high-flow header-based exhaust system, that there is a 62 hp increase over stock. DeLoreans normally make about 100 hp to the wheels in stock form, so if the 62 hp gain claimed by the DMCCAL web site is measured at the wheels, then I can calculate engine output at the crank shaft based on the following formula: (162 x 130) / 100 = 210.6 210 hp!!! That is the same HP rating that the Island Twin Turbo Kit literature claims (I know because I have the literature)! Don's Crazy Cams make the idle a little rougher than normal, but allow the engine to breathe better which in my opinion adds character to the engine and the car overall. Having driven other DeLoreans with these performance cams I can say that the revs come easy, there is no feeling of the engine being choked with the engine really opening up to revs at around 3,500 rpm and up. According to Don Steger the redline is 1,000 rpm higher than stock. Dom Steger's High Performance Cam Shafts really inspire spirited driving. Pros: The engine breathes and revs much more freely than stock, strong aggressive idle, 62 HP gain when used in conjunction with a free flowing header-based exhaust. Cons: It is a little on the pricey side ($600 + core) when compared to cams for other makes, the slightly rough idle may make some owners think their car is not running right, not for use with forced induction. Conclusion: I love Don Steger's Crazy Cams (High Performance Cams part # 102707HP) and they are my recommendation for those wanting improved performance over stock, but want to avoid complete engine swaps or forced induction (turbochargers or superchargers). Note: When running Don's Crazy Cams, adjust your timing from 13 degrees to 20 degrees. Also Note: Don's Crazy Cams are not for use with forced induction (supercharger or turbo) because of cam lobe overlap changes, which creates blow-by. Hervey's Headers - I have been around many other DeLoreans with exhaust systems from other vendors as well as one-off custom systems both header-based and manifold-based, and as of this writing there are a few off-the-shelf DeLorean exhaust options currently available to the community: DeLorean Motor Company (DMC) (www.delorean.com/store/p-10337-stage-i-exhaustignition-upgrade.aspx <http://www.delorean.com/store/p-10337-stage-i-exhaustignition-upgrade.a\ spx> ) Stainless Exhaust Specialist (SES) (www.stainless-exhaust.com/pictures.htm <http://www.stainless-exhaust.com/pictures.htm> ) Special T Auto.com, Inc. (STA) (www.specialtauto.com/delorean-parts/delorean-parts-kits.html <http://www.specialtauto.com/delorean-parts/delorean-parts-kits.html> ) What do these off-the shelf header-based systems have in common? They are all available in stainless steel. What are their differences? ? DMC has long headers, SES & STA have short headers. ? DMC comes with catalytic converters, SES has the option of catalytic converters or flow-through pipes, and STA does not currently come with an option for catalytic converters (other than buying cats and making your own system from the headers). ? DMC & SES use flanges at connections, STA doesn't have flanges and requires clamps or welding. DMC & SES are cross-over exhaust ONLY, STA is optional for cross-over or for true-dual exhaust. ? The biggest difference that I found between the systems is the ones from DMC & SES will cost you about $2,200 plus shipping to purchase while STA is priced @ $995 + shipping in all stainless true-dual configuration. Hervey Header History - The Special T Auto - Header-Based True-Dual Performance Exhaust System, or the headers more specifically were originally developed in the 1980's and, as far as anyone can tell, are the first headers made available for the DeLorean. John Hervey of Special T Auto came across the original welding jig and started having headers made, initially in mid steel with ceramic coating, then transitioned to polished stainless steel. Keep in mind that John Hervey of Special T Auto has said that he does not want to be in the exhaust business, but is providing these headers and associated accessories as a means for owners to create their own custom exhaust systems on their own. Pros: Price, ease of assembly, finish quality, tucks nicely up and out of the way, can be installed at home without special tools or equipment, completeness of kit, sounds very aggressive. Cons: No O2 bung on left header collector, uses clamps instead of flanges, no option for cats to replace mufflers in True-Dual System, completeness of kit, sounds very aggressive. Yes, I know I said, "Completeness of kit" and "sounds very aggressive" in both Pros and Cons, but let me explain. Completeness of Kit - When Dave Watts ordered his kit he requested that a stainless O2 bung be installed (read "welded") to the driver's side header collector so he could install the system, be done, and not have to try to find someone to drill and weld it for him, it was not done and Dave will be running without the O2 sensor installed until he can find someone to weld a stainless O2 bung for him. Dave's kit also arrived without the exhaust tips. This is both good and bad in that the tips that come with the system are chrome and are welded or otherwise affixed somehow to the outlets of the stainless mufflers. Why not just extend the muffler outlet stainless pipe, slant cut it like a tip, and polish it!?! Stainless looks great when polished and would be an improvement over welding dissimilar metals together. Sounds Very Aggressive - I would describe the sound of the stock DeLorean exhaust to be similar to that of a high-powered sewing machine, a 130 HP sewing machine to be exact. When experiencing a Porsche or Ferrari (new or old) they each have distinct sounds, and in reality, the car stereo will only tend to distract from what is really important when behind the wheel of such visceral machines as older exotic sports cars. Unfortunately, this is not the case for the DeLorean. For a vehicle with fabulous style and handling to have such an anaemic engine and choking exhaust, it is almost an embarrassment. When at a car show, and either a DeTomaso Pantera or Lotus Esprit start up, people listen and swoon, then follow you to your DeLorean and wait for a glorious symphony of internal combustion, waiting, listening, then asking if there is something wrong with the engine, or worse, asking if there is a mouse hiding in the engine compartment. If you install the Special T Auto Header-Based True-Dual Performance Exhaust System, you will no longer be able to go unnoticed. This system is loud and aggressive, it is not mellow even at idle (thanks to Don's Crazy Cams), and people (both the general public and law enforcement) will hear you coming. There is a low frequency rumble and occasional spats and popping when letting off the gas (no catalytic converters), but when putting the pedal down, the aggressive rumble opens up to an almost breathiness, yet without the rasp of a Japanese Import, although it seems close in many ways when approaching 5,000 rpm. The good thing is that it sounds nothing like the stock DeLorean exhaust and at the other extreme it does not sound like the "Ricer" coffee can exhausts that are so common in small displacement (less than 4.0 liters) engines today. It sounds meaningful, serious, and playful, but not completely juvenile. I like it. Thumbs up!!! Verbose Conclusion: The system Dave Watts' installed in his DeLorean is the Special T Auto - Header-Based True-Dual Performance Exhaust System as is shown here (www.specialtauto.com/delorean-parts/images/header-kit-2.jpg <http://www.specialtauto.com/delorean-parts/images/header-kit-2.jpg> ). While it started as a standard request, Dave did request a change that was accepted and confirmed, but not implemented as mentioned above. I know that John Hervey is a very busy man and sometimes things get forgotten and besides, it's not like Dave can't get a bung welded locally. Anyway, the Special T Auto's True-Dual version application of these headers is probably not the exhaust for those wanting a quiet relaxing drive, but in the short six mile drive near Usery Park in East Mesa, I enjoyed the exhaust note quite a bit and I couldn't help, but wonder how I would feel after a drive to Flagstaff or Tucson and back. My wife said that somewhere between Stock Quiet and True-Dual Loud would be right for her. Perhaps it is a little too loud for long drives or sneaking through neighbourhoods late at night, but in my opinion it is fine for jaunts to local gatherings or for times when you just want to get out and drive. We'll see what Dave does with the restricted mileage of collector car insurance, it may inspire him to add some dynamat to his firewall or he may think it is fine. For those interested in something quieter and still affordable, the Special T Auto offers a Cross-Over muffler for use in the same familiar configuration used by DeLorean Motor Company and Stainless Exhaust Specialist, but will require fabrication for pipes, stock exhaust hangers, and possibly cats if needed for smog testing. Which system is right for you? That depends on what you are looking for. For Dave, he looked at all of the exhaust systems available and decided to go for the Hervey Headers because he wanted a system that has short headers, is a true-dual system eliminating the heat shield and engine mounted exhaust hangers, catalytic converters were not needed because he plans to have collector car insurance and will be exempt from emissions testing in Arizona and this system is ideal in that it eliminates the catalytic converters, he wanted something with a loud and aggressive sound, he also wanted the whole system in stainless steel, and didn't want to spend a huge amount of money. These are all very good reasons to install the Special T Auto Header-Based True-Dual Performance Exhaust System. Nutshell Conclusion: I like the headers with optional accessories that Special T Auto has come up with. It allows owners to design what they want based on their insurance or emissions restrictions. With Don's Crazy Cams and Hervey's Headers installed, the engine really opened-up and seemed to have no problem moving the car out of its own way. I found that the sound of the exhaust inspired me to put the pedal down even more and I really wanted to be thrown into my seat, but even with Don's Crazy Cams and Hervey's Headers making an estimated 210 HP *, it is still not at the magic 10:1 pounds:horsepower ratio that will provide that push in the seat of the pants. That being said, Special T Auto's Header-Based True-Dual Performance Exhaust System looks good, sounds great, and is affordably priced. * It did not feel like 210 HP, but the math** worked out that way. It felt more like 170 HP, but my sense of power may be off. Only the dyno knows! ** 100/130 = 162/x, x = 210.6 HP, Renault R30 UN1 gearbox has approximately 23% parasitic loss. Recommended Changes: 1. Stainless steel O2 sensor bung installed on the driver's side header collector out of the box. 2. More development as far as complete interchangeable accessory options for Hervey Headers (True-Dual w/ out Cats, True-Dual w/ Cats, Cross-Over w/ out Cats, Cross-Over w Cats, or my personal favorite True-Dual Headers, Cats, SuperTrapps for a tunable power/torque curve). 3. The headers currently point out left and right toward lower pontoons, and I would prefer them to be turned near or at the collector so that the collector outlet is aimed directly aft and aligned with the rear fascia exhaust cut-outs. 4. A headers-cats-tips accessory option would be nice for swap-out for people wanting True-Dual Exhaust, but need to pass emissions. 5. Consider standard three-bolt exhaust flanges for connections between headers and accessories. 6. Stainless steel tips. Ref: http://en.wikipedia.org/wiki/PRV_engine <http://en.wikipedia.org/wiki/PRV_engine> www.dmcnews.com/Resource/horsepower.html <http://www.dmcnews.com/Resource/horsepower.html> www.deloreans.co.uk/links/links.html <http://www.deloreans.co.uk/links/links.html> ADDENDUM: It has been two weeks since I posted the above to the AZ-D Yahoo Group. I have since ridden along with the car's owner Dave Watts on a moderately lengthy cruise and discussed the exhaust system with Dave Watts, John Hervey, and members of the AZ-D and I would like to add the following notes and points of conversation: 1. Prior to the cruise, Dave had the O2 bung installed on the "S" pipe between the headers and the mufflers. 2. Participants in the cruise made note of the exhaust tone and seemed impressed, remarking that it sounded great while cruising. 3. The lack of included exhaust hangers did present concerns while participating in the cruise as I had to fashion one from a wire clothes hanger to keep the passenger side muffler from swinging downward when hitting bumps in the road. 4. During the cruise, Dave agreed that the system, as it is, is too loud for him, but that John Hervey is also providing muffler inserts from Car Chemistry (www.carchemistry.com <http://www.carchemistry.com> ) that will provide sound deadening and some back pressure. 5. I discussed with Dave how a completely unrestricted exhaust is a performance benefit in forced induction applications, but is a detriment to low-end torque in naturally aspirated engines. 6. I told Dave Watts and John Hervey about my preference to have regular (non-collector) car insurance for daily driving and unrestricted mileage, but also pass emissions and still have True-Dual Exhaust (no heat shield, no engine mounted exhaust brackets), and that there is a need for tunable back pressure that will accommodate any variety of engine modifications. 7. I asked Dave to measure from the rear face of the bumper to the forward-most face of the muffler and the result was about 22.5". With that in mind as the available space for a new configuration, I determined that the same series of catalytic converter that I use on my custom turbo system is short enough to fit within the available space, (www.car-sound.com/02product/universal/mirror.asp <http://www.car-sound.com/02product/universal/mirror.asp> ) (this was simultaneously suggested by John Hervey while discussing a headers-cats-tips configuration). So that from 22.5" of available space ? a MagnaFlow Mirror Finish Performance Exhaust Catalytic Converters Part #'s: 54306 or 54306M (9" body, 13" Overall Length) = 9.5". With the remaining available space I determined that the only tunable muffler that will fit is the SuperTrapp Wavetech Part #: 456-2508 (www.supertrapp.com/product_sections/detail.asp?CatID=26&ItemID=456-2508 <http://www.supertrapp.com/product_sections/detail.asp?CatID=26&ItemID=4\ 56-2508> ). This SuperTrapp Wavetech has an 8" length and a 2.5" inlet, and is polished stainless steel. While I prefer the look of the SuperTrapp Polished S/C Elite series, the shortest of that model is 10" long and only has a 2.00" inlet. Using a SuperTrapp combines a muffler with an exhaust tip and eliminates the need for two separate components. While I would prefer a slant cut SuperTrapp, I can live with the Wavetech. 8. After discussing the addition of a Headers-Cats-SuperTrapps configuration for Hervey Headers, I noticed the addition of a link to the SuperTrapp Automotive section on www.specialtauto.com <http://www.specialtauto.com> ? (www.supertrapp.com/product_sections/auto/index.asp <http://www.supertrapp.com/product_sections/auto/index.asp> ). Re-evaluated Recommended Changes: 1. The headers currently point out left and right toward lower pontoons, and I would prefer them to be turned near or at the collector and as close to the rear cross-member as possible, so that the collector outlet is aimed directly aft and aligned with the rear fascia exhaust cut-outs. 2. More development as far as complete interchangeable accessory options for Hervey Headers - True-Dual w/ out Cats, True-Dual w/ Cats, Cross-Over w/ out Cats, Cross-Over w Cats, or my personal favorite True-Dual Headers, Cats, SuperTrapps for a tuneable power/torque curve. 3. Add pre-made "S" pipe options along with the headers. 4. Stainless steel O2 sensor bung pre-installed on the driver's side "S" pipe. 5. Include frame attached exhaust hangers. Sorry this review is so long, but there was a lot to make note of. Round up: The High Performance Cam Shafts (Don's Crazy Cams) from DeLorean Motor Company ? California, are a "Sure Thing" regardless of what exhaust you run. The Stainless Steel Headers and associated accessories from Special T Auto, are a great buy and allow for owner creativity when it comes to personalizing your exhaust, your engine performance, and your car. Whew!!! Ben Ferguson (Captain Hydrogen) Mesa, AZ VIN 6477 VIN 10365 www.az-d.org <http://www.az-d.org> [Non-text portions of this message have been removed] ------------------------------------ To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnewsYahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: mailto:dmcnews-digest@xxxxxxxxxxxxxxx mailto:dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/