preith

Here's the ITS results Unfortunately they don't have the car makes listed too. Looks like Chet won again, I'm assuming in a Z, which makes me think maybe the Z's days in ITS aren't as numbered as some say.

What aftermarket brand was it? I'm curious, I purchased mine from Victoria British. It's made by PPG. When I saw that, I didn't have any worries since it was from a reputable brand. How old was Mark's? With the age of these cars It wouldn't surprise me if it's been around for a while even if it is an aftermarket unit. I've owned 2 vehicles from Texas, both with the original glass, and were both pitted badly. One was a '77 Z, and the other, my current tow vehicle, '94 powerstroke Ford.

I find it much easier to listen to someone who is obviously very knowledgable, but is quick to state that they don't know everything. I was going to mention the same thing. I'll probably get some heat for this, but one of the reasons I chose to stay with the softer springs was because I'm using Illuminas and don't want to fork out dough for those AD's as of yet. $1600 is not a cheap proposition. I know, I know, stay out of racing if you don't want to spend money, but I think for now at least I've made the right choice. I need much more seat time before I start tweaking the suspension more; 5 race weekends just doesnt' cut it.

Hey Cary, thanks for the input. I guess I quickly forget to ask the z community "suspension expert" to join in on the conversation. According to your equation for DOT R's, with a nominal weight of 2150, this would put the spring rates betweeen about 270# and 375#, which very close to the two setups which katman refers to, interesting.

I really think part of your problem may lie with the difference in spring rates. Most setups I see don't vary more than 50 lbs, and yours are by 100. Also, I don't know what kind of struts you're using (illuminas??), but in the thread he mentions Illumina's don't react well to any spring rates over 275, and I've heard this elsewhere. But you say you've ran the car like that with the slicks, so who knows... If you do in fact have smaller diameter bars, I'd try the rates that he has on his car, or in other words increase your rear rates by 50#. As a stop-gap measure, you can slot the strut towers for camber adjustment.

A Corvette wrecked at Putnam, a fence post went through the car, then through the drivers seat and broke his shoulder blade. Could've been much worse... There are pics about 1/2 way down. http://www.nasaforums.com/viewtopic.php?t=6643

I don't have any real world V8 Zcar experience, but IMHO the Rover V8 just isn't worth it. The weight savings over a Chevy V8 with aluminum heads is minimal, the Rover doesn't have anywhere near the same amount of aftermarket parts, and the Chevy will be much more powerfull for less money. Also, It's been stated many times before that a Chevy small block with alum. heads is only slightly heavier than the L6, something like 50 lbs.

The spring rates issue really seems to be a can of worms. You don't hear it too much anymore, but especially in IT there was the east vs west coast set-ups. The east coast guys liked stiff spring rates, stiffer up front, with small bars, and the west coast the exact opposite. Here's a VERY good thread on the topic: http://zdriver.com/forum/showthread.php?t=6075 From what he's written, your numbers seem to be in the ballpark, even with the stiffer up front, but you might still want to try a slightly stiffer rear spring. Basically I have a west coast setup on my car, which I run 225/50/15 Kumhos on. I must have gotten lucky with the setup, because right out of the box it was pretty good, and it doesn't push much. I'm at the 250 front/275 rear numbers which he scoffs at, but it feels real good to me. I'm running a 1.125 front bar and a 7/8 rear. He mentioned chassis distortion, but my car is more like a production class chassis, which much more rigid than an IT car. It seems like the toe setting is critical on these cars. Right now I'm at about 1/32 in on the front, but many guys run a slight toe out, which he describes as well. Also, this will bake your noodle. I remember a discussion on HybridZ a while back about NOT running the same spring rates on all 4 corners. I was talking with a local autocrosser, Mike Tews, who also co-drives John Anderson's Z at the soloII nationals. This car is very competetive. If I remember correctly, he said they were using 300lb on all 4.

I don't seem to remember mine being 2", maybe an inch at best. I ended up cutting the end to a point, or a knife point, and putting as much surface area of the 1" sq tubing as possible on the rocker side, but yet still have enough area to form a T weld if that makes any sense. I did not use any plating to reinforce it on the floorboard side. All in all, I thought it was a pretty easy mod.

Man, I have GOT to get a digital camera! Unfortunately, I don't have any pics, but I think it's pretty self explanitory. I don't have any data or proof to back it up, but an old timer I used to hang out with, has tried both methods seperately (across the tunnel and to the rocker panels) said they both have the same affectiveness. So it was my guess that both isn't needed. It also makes for something else to get in the way during engine/trans removals and installations. I suppose it would be pretty easy to fab some kind of removable one if you really wanted both.

I actually haven't played much with camber. There was a very good link on Zdriver.com in the racing section which had a guy's setup on his IT car. I figured I would copy his as a starting point. The fronts are at about 3 degrees and the rear 2.5 degrees. This past summer was my first serious attempt at road racing and I really haven't played with the setup too much. I figured my car feel should get better first. I have the Arizona Zcar chromoly arms and tension rods (castor/radius), which utilize a clevis pin on the control arm and a rod end on the chassis side for a solid link. Right now the tie rod ends are actually stock units, but I plan on converting over to rod ends for that as well this winter (heh, your summer). I have the "bump steer" spacers as well. I've heard many guys complain of instability during hard braking if their bumpsteer isn't just right, but I haven't bothered trying to adjust anything and it's been rock solid. I think part of that may be because of rigidity, there is 1" square tubing connecting the tension rod mounts to the front corner of the rocker panels. This is an old trick and I can't take credit for it.

225/50/15's, and I don't know what compound. As far as I know there isn't any selection available.

From what I've read on the SCCA forums they are in somewhat limited supply, but nobody on that board has had any problems getting them. Per my 1st post, I'm really interested in buying a set but am a little apprehensive how they will react to road racing.

The V710's were discontinued temporarily due to sidewall failures, or something similar to that, but were reinstated in the spring of this year. If they've been discontinued again, it's news to me. Even with that blemish on the record, since then they've received rave reviews from the autocross crowd who say they're better than the Hoosiers.

I checked out Kumho's Austrailian site, and it looks like the ECSTA V700 sold here in the States. I have these and am very happy them. These are the only ones I've ever used and there are so many variables, but they seem to be comparable to what other guys are using. I'm contemplating purchasing a set of V710's, but have heard mixed results with the wheel to wheel guys. Some say they're really good for the first 10 laps, but then fade off quickly. The autocrossers really like them, which would confirm this in my mind.

My 8 gallon ATL sports cell will be for sale shortly. It's manufacture date is about 5 years old, but it's only actually been used a little over a year. Anyone who's interested PM or email me.

I realize this is an old post, but I just wanted to throw in my $.02. I have an 8 gallon cell, only do sprint races, and it's not large enough. Well there's BARELY enough fuel for a 1/2 hr session depending on the track. Part of my problem is the fuel pick-ups, I don't have a surge tank or enternal box to pick up every last drop, but after a session it has less than an inch in the bottom. In my club there are a few events which are 40 minutes and this being my first year, I've had to duck out early and just take the novice sign off (at least 1/2 the leader's laps).

Jetting may fall into the "black magic" realm but this is pretty straight forward, or at least to me. Basically the holes which are epoxy'd shut were originally the vent holes for the float bowl. This simply keeps the bowl from being pressurized and allows fuel to flow in. What happens under high g-load right handers is the fuel sloshes over to that side, comes up through the holes and then flows over on top of the jets. This causes an extreme rich situation because the air jets are being blocked off completely.

Thanks for the photos. It looks like they did in fact epoxy shut the bowl holes as well.

On somewhat of a different note, I'm really looking forward to watching the Goodwood Revival on Speedtv. Does anyone know when that will air? EDIT: Ok, I'm a bit confused now. I was google searching for this and I can't remember which one is Goodwood Festival of Speed, and which is Goodwood Revival. Basically I'm interested in the one with actual wheel to wheel racing.

Not to beat a dead horse here, but as far as I know, you have to do more than just vent the bowl. If you end up venting the bowl on the large cover, you can then epoxy the holes in the jet chamber area shut (the ones which allow the fuel to flow in from the bowl). Keep the end open then to vent the jets. Phil

Basically that's what I was trying to point out in my previous post, keep the fuel off the jets. It sounds like my modifications are diferent from Tom's, but accomplishing the same thing.

IMO the stumbling cannot be corrected by running a lower float level alone. Beleive me, I have tried it. If there are others out there that don't have any problems I'm all ears. I road race my Z and feel the higher G-forces inherent with race tires enhance this problem even more. Wolf Creek Racing modifies the carbs extensively to correct this. Unfortunately I don't have any pics, but what I ended up doing was epoxy'ing another piece of aluminum on the float cover so it seated against the rib in the float chamber. I then drilled a single hole in each cover above the jet area for venting and epoxy'd a 90 degree vacuum fitting in it. Seemed to do the trick. Also, Dave at Malvern Racing told me they always ran 4.5psi with a 2mm seat in every one of their road racing cars. Just an FYI, but Dave passed a few years ago now and the business has subsequently folded. As for the dual pumps question, I have a two pick-up fuel cell and originally had a pair of solid state Facet pumps. I found that even with two it wasn't able to maintain enough fuel pressure at higher rpm's. I switched to a single Carter competition pump (which flowed more than both the Facets) and don't have the issue anymore. I also have two pick-ups feeding to the single pump and do have problems once the fuel gets low. I'm going to install a surge tank this winter to correct that.

If my memory serves me correctly, the hazzards will still work even if a bulb is burnt out. I'd be willing to bet this is the case.

Once again great pics. I'd LOVE to see some GT2 pics too if you have 'em.