Get or look into some Nitto Nt555R Drag radials 275.40.17 they are the most amazing tires that I have ever owned. Also, they handle and stick on corners like you would not beleve. If your sitting at a stop like and you nail it, they hook reall well. I had traction problems all the way through the end of third gear and now, it feels like a differnet car. I had never experianced the feel of that in my car.

 

What's the lifespan of a Drag Radial?

 

I don't want to go OT for you Paul, but, if you were to do a search under Special Tool, you would see he has traction issues with his 2.5L. I've been in the car with him, with 275s on the back, temps about 65-75, boost about 21/23, 3rd gear, and would spun the wheels bad. Another person with traction problems is Joe, known as "Defastest951" who has a 3.0L 951 built by Powerhaus. Here are the specs when it was first built too. Joe's 951 3.0L Car.

With my old car, I "only" had 265s on the back and had bad traction issues too. I recall several times running at 18PSI making only 460 RWHP, air temps exceeding 80+, in 3rd gear at 65 MPH and my car made the tires do a full burnout, not a spin or a chirp. At a minimum, with that car of yours for the street, even with very modest boost, I'd get 295s on the back. Trust me, you'll need them when that car is tuned right and broken in too. The track set-up is even a different story too. I am doing extensive research into both applications as we speak. I'm looking at custom wheels made by two different companies. Anyway, sorry to go OT pal.

 

These drag radials are good for close to 15 to 18k. you do not need custom weels or anything like that they cost around $150 each and I have a 2.5 with a over 400whp at 23psi and Im telling you guys you gota try out these things. like I said before, they are the best handling tire I have ever owend to a point that the car can understeer in some situations, thats how stable the rear end is. And as far as accleration they rock, and no you do not need to do a burn out to get them to work properly. if your drag racing and you want to at that point. check them out on their web site.

 

So what are the other tires you have owned? Let us know what you are comparing them too.

 

Hmm, are you sure those are drag radials? What brand and model? Usually DR's in a decent size are pretty expensive. At one point I had BF Goodrich Gforce t/a DR's in 275/35/18 on my 911 at 430whp. I think they were around ~$200-250 a piece. They were gripy enough that I'd just barely spin through second, and would grip in all other gears. Just FYI but DR's don't last very long. They have very soft rubber compounds, and regular street driving will wear them out pretty quick. I think I got something like ~4-5k of realistic life out of them driving on the street with the occasional spirited run, and after that they were pretty much bald. They grip hard, and even on damp surfaces, however they handle like complete @ss compared to any decent performance street tire (Falken 615's, S02's, Pilot Sports, etc). DR's have very soft sidewalls which does not work well for handling. My 911 felt a bit "floaty" on the highway because of this. If you are used to crappy econo tires, I'm sure any DR's are going to feel light years better.

Well, I took a look online at the Nt555r's. Here's Nitto's Link and here's the link to the BFG's I had Link

It looks like the Nt555r's aren't really a true DOT legal DR in the same sense of the word. BFG's like the one's in the link above are more along the lines of what a street DR is like. It appears like the 555r's are more of an R compound then an actual drag radial. Either way, from what I hear from friends, the 555r's seem to be pretty decent, and I'd be willing to bet that they'd definitely handle better then the BFG's.

 

PIC and VIDs YET

 

I have had pilot sports and other high end street tires and all I can say is I have not had a tire that grips like this on corners and going stright. Im not trying to sell these things just giving you my opinion on them that is all. i think they only come in 275.40.17 and they are the 555R tires also, they say extreme drag on the side wall. As far as cost, they are pretty cheap and dont cost that much.

 

Back on to the program. First, Happy New Year to all of you guys. I hope you had a safe and wonderful New Year. Anyway in your post above, if the chips you installed are 2.5L, aren't you concerned even at this stage with the timing? I would think that the timing in a 2.5 chip is very different than in a 3.0L+? If they are different, which I "believe" they are (don't quote me) wouldn't you be a bit apprehensive about trying to get a good map, let alone the chance of the hurting something with running different boost levels?

 

The chip installed, in theory is almost a "safe mode" 16-18 psi for this engine. Due to the 3.2 design in theory the optimum for this engine would run an ignition map with more advance due to the increased area for the flame front to cover. Even though the ignition map isnt advanced as far is would be optimal it of course isnt retarded to a point which is dangerous either.

Paul should be getting a dedicated map shortley, which will release much more power and hopefully clear up one of the few problems with Paul's car, which is the first few moments when its cold started it runs a little rough (and rich)

Your right though... the ignition maps are very far from ideal at the moment, not to mention the fuel could be optimised a little at high rpm, along with everything being setup to run 3.0 bar of fuel pressure rather than the 2.5 its running at the moment.

 

Thanks for clarifying those things. So, are you at liberty to say what the plan of action is? Paul mentioned he was going to look into a lot of Vitesse items, is this still true and when? If so, what EMS things are you planning on getting? The Vitesse MAF and custom chip-boardset?

 

Paul is keen on the Vitesse MAF... He is also keen on a dedicated map for his car.

The worry is, a chip tuner is going to be uneasy messing around with the maps when VR MAF has its own engine load/airflow code in the chip...

I need to get in touch with John at VR and have a chat to him about what he can offer, as the ideal solution it would seem would be a VR-MAF, with a map that he thinks would see us in the right ball park, and then ideally a version of VRLiveEdit but for the VR-MAF, so we can then go on a rolling road and fine tune it a little and continue developing things further without bouncing rom images back and forth across the atlantic to and from JV just because we want to try out a "what if" alteration with the mapping.... But I dont think this is available (VR-LiveEdit for VR-MAF)... (

There are fundamental flaws in the other MAF's on the market at the moment, which makes us steer clear at the moment or at least makes me have concerns.... But so far with what I have seen of the VR item, it seems like the proper way of doing things.... If only there was VRLiveEdit for the MAF version of the prom!!!

 

So Paul is keen on Vitesse? Glad to see that mate! And yes, get in contact with John too, he is a great guy to work with and his MAF and chips are by far the best on the market. Now I could be mistaken, but I was under the impression that if you use his MAF, using the VRLiveEdit would be going backwards? I could be totally wrong on that, so get in contact with him and let him clarify.

But let me say this about John and his products. I have used just about every product he offers, and to me, they are by far the best! I was just posting in another thread my experiences with his MAF and custom chipset-board. With John's chips, right out of the box you will find that his A/F is 95 - 98% on the money, and I'm not kidding at all. If you want to use a Piggyback and get it better, you can tweak it some more. But I was astonished at how close to perfect it was for me after we just plugged it in. I bought his SMT6 software, and Special Tool and I did a few datalogs while driving the car. We also used the Zetronix ZT-2 to view all the variables too. That is an amazing tool I might add. Then, we tweaked it a bit more and got it even better!! And I'm sure you know this already too, but with his chips, the A/F ratio will remain perfect regardless of what PSI Paul runs. No more of having to retune it for hours and hours for different boost levels. Anyway, I hope this clarified things a bit fot you? As I said, I may be wrong about the VRLiveEdit, so ask John.

Cheers

 

All we really need to be able to do is have a VR-MAF and some way of altering the ignition and fuel mapping ourselves without having to dig around with a hex editor... Is this what the piggyback does? it allows ignition and fuel trimming of the maps?

I will get in touch with John tomorow once I have had another look on his site to get an idea of his products... I think its the way to go, either that or stand alone.. But it would be nice to stick with the motronic and I expect Paul would probably like to save a few bucks over a stand alone as well!

 

I am not even going to touch this one. Contact John for the specifics of his products, that would be best. But you now know my personal experience with my other 3.0L and his products.

And a EMS for Paul? Honestly, from what I understand how Paul plans to use the car, that would be overkill. John's EMS stuff sound to me like the ideal answer for Paul's application. Reach out to John, and let us know what happens. And hey, tell Paul to get his butt on Rennlist and post once in a while, and to give us some more pics too!