Dave C

If you have a TT you want as little backpressure as poss, no backpressure would be ideal. No restrictions = maximised gas flow = faster turbo spool If you have an N/A then the correct amount of backpressure is essential, due to the exhaust gas scavenging effect. Removing all backpressure from an N/A would make it loud but the performance would more than likely be awful. We have spent a long time researching the characteristics of exhaust backpressure on the N/A recently, using an in house Dyno and many different pipe lengths. The results were very noticeable The only reason to maintain backpressure on a TT is to protect the turbo oil seal. If you have a low mileage healthy engine then the chances are you will be ok de-catting. If you de-cat and the seals go, then they were on the way out anyway. Like anything on the Z its just a matter of time.

Just get the Nismo ones, you can pick them up for not much more than the ones in question

Keep your cat pipes and your cat back system separate. This gives you flexibility in the future may you require to repair or replace a section. If your worried about the tubs seals then just add a cat back system for now and maybe a pair of cat pipes with built in "sports cats". Although these offer improved flow characteristics over standard cats, they also provide a certain degree of BP. The BP vs Tubs seals theory is only really apparent with standard tubs/seals. If you have after market tubs then there is a good chance your seals have been upgraded.

Thanks Gio for that, I have had a glance through and can see both sides of the story. Like most things the real test is the consumer, it they are happy with the results then that’s good enough for me. Ferrari and Lambo owners using them does give me confidence, regardless of scientific results. Its the same old argument...........Recircs or atmospheric dump valves, auto or manual, black or red.... There will never be a true answer. Have to admit, until I attended the classic car show the other day I too were sceptical.

Its no gimmick, thousands of classic car owners use them. I was at a show the other day and seen them fitted to Lambo's, Ferrari's and a Shelby Cobra. Speaking to these guys they have used them for a while and swear by them. There were 4 TT Zs with them fitted, everyone with the same result. Apart from performance increase most owners noticed the MPG increase more than anything. The manufactures give a 5000mile money back guarantee, you don’t like the effects of the Cat within 5k and you get a full money back refund. Have just ordered one for me pops 928s4, as since 4 star was removed from the pumps he has not used the car once. :cry: Oh and of course our Zs, will be running them when they arrive. Please note for older cars. Although the fuel cats raise the octane of standard unleaded fuel to that near leaded 4 star, you still need to add lead for engines running soft compound valves/seats. This does not included the Z32 as stated before, is built to run without additional lead added. Try one out, within 5000 miles you should of made your money

It will raise your octane by anything upto 5-6 points, you will prob not notice any performance difference running at 1 Bar, but you will get more MPG. If you want a fuel cat, dont use Optimax as it will be overkill. The idea of the fuel cat is to save you money on more expensive higher octane fuel. If you want one iam putting an order in Wednesday, just give us a bell ;) PS..Do u still want the rad

Words of wisdom ;)

The Z runs on HDHO unleaded fuel only, the engine was designed that way. Forgetting about the cats “the lead will indeed destroy them”, LRP contains no lead, as this was replaced with other chemicals, it still contains that vital valve lubrication required by older engines. With the Z having hardened valves, no lead or LR is required. Leaded petrol did indeed have a higher octane level of 98-100 compared to un-leaded petrol, due to Shells Optimax being launched the octane levels are now very close. I have copied this info to give you some idea where we are up to regarding today’s octane levels Unleaded Fuel Types Octane Rating Unleaded ULP(also known as Regular Unleaded) 91 Octane Premium Unleaded 95 Octane BP UltimateShell Higher Octane Fuel Shell Optimax Mobil Higher Octane Fuel called Synergy 8000 98 Octane What are the benefits of using higher octane fuel? According to fuel companies, some of the benefits of using higher octane fuels can be: - improved engine responsiveness - better fuel economy - greater fuel efficiency - cleaner engine - better driveability - lower emissions and therefore a cleaner environment NOTE: Higher octane fuels contain cleaning agents that are said to assist the removal of carbon deposits in a car’s engine and protect it against corrosion, allowing the engine to function better. Why dont you just use 95 ron unleaded with a "Fuel Cat". It will lower the emissions, higher the octane level to that of Optimax and give you better MPG at a fraction of the Optimax cost. You will also be able to boost fully without the dreaded knock knock sound found when using low octane fuel. The Fuel Cat last around 60k mile's so just think of the fuel price savings you will make. For your car they cost around £65-75 depending where you purchase it from.

Please understand that “fellow members” generally offer several similar products, budget and premium or alike. It is up to the consumer to decide what he/she really wants. If 2 similar products differ greatly in price, it is usually down to quality and brand. Not everyone can afford the premium brands so make do with lesser products. As long as the consumer is not misled in anyway, everyone’s a winner :)

Yes this often happens when someone is trying to be helpful, the guy seems to know what he is talking about. He is not benefiting from supplying this information, so unless he works for “Carbing” this information should be treated with some value. You do get what you pay for, well most of the time. You want high performance? You pay high prices.

We ran our car "shown in pic" on the rollers that day with and without the new pipes. The power increases for $$$ were excellent. These guys really know how to build systems. Its a shame you dont live closer as I could give you a free session on the dyno after your pipes are fitted. I will call u as soon as production begins.

Almost there bud, here are some sneak previews I took whilst visiting. Jigs done ready for production :bow: Mowgs....I have not forgot

Count us in, should have more cars this time ;)

Wez was good to meet u and the other guys. Was indeed a great day, I have loads of pics and a video of the convoy driving through Mac. Will compile them and bring them with me next Saturday. I am thinking of having a stall at tat , as iam currently in discussion with Keith about becoming the clubs supplier for aftermarket parts :hyper:. Give us a shout in the week. :D

Untill I get my new ones, Iam running a front n rear courtesy strut brace with a rear Ladder bar also. The car feels solid and the back end wobble has gone.

cont....

The QV is my fav car of all time, how bout this one 9k km from new V12 500bhp for only 45k.

Cusco do a very nice set, front and back. Will post a pic when they arrive :dance:

Will see you there :dance:

Pete, good to meet you at Phils the other day Phil can sort everything from engine rebuilds to full resprays, he uses a top local company for his bodywork. He also builds nice exhaust, as fitted to the "Petrol mobile" PS..Give us a buzz asap about Sunday

Wez there should be 3 or 4 Zs arriving with us on 29th, we are meeting some others around junction 19, should be a good day

Sorry James and thanks for the Tip :)

As explained to viniboy, the workshop manual is not our property by all means but the extra content is. I have also told Viniboy that there is a PD copy of the actual manual on the 300 site. I have ask Viniboy not to distribute our CD freely. Thats all so dont get excited

Only Auto's left

As usual we will be bringing the Conzult and a few bits n bobs. Any special request/requirements please contact us ASAP, to avoid disappointment ;) Thanks