JMortensen

Man, I feel bad for you Mark. Every dyno session, with the latest iteration of the motor anyway, has been a clusterfuck. I hope you get it sorted. I am pretty sure you're running the Porsche style CVs. I've heard of the bolts coming loose on quite a few different Datsuns. Might be a good idea to safety wire them. Could do the same with the driveshaft bolts too if you want.

We should have a betting pool. I can't remember if you have an air filter. If you do, I'd put my $5 on the stack second from the right making the most power by 2 hp.

I'm rubbing nickels together but should be able to get mine up and running again in a month or two. Have a bad master and need to replace the tires just due to age. Was carb tuning last time I ran it, too. Big problem for me is that I was way over the dB limit last time. I put Supertrapp tips on my mufflers, so hopefully I can just adjust it until it passes, but that might affect the carb tuning and all the rest. If I do get there, don't expect a lot is what I'm trying to say...

This looks like a question for ls1tech.com. From some quick reading, shorties are worth next to nothing compared to stock manifolds, big increases possible with long tubes.

The general answer to your question is "as far back as you can manage." John's Cars kit puts it at about 4". I moved mine further back, IIRC I'm at about an inch and a half on the pass head. It's not a simple thing. I had to cut the trans tunnel for clearance in front, and the 70 tunnel is narrow so I had to beat it with a BFH to make it fit. If I went further back I would have had to cut the tunnel in the rear too, or just cut the whole thing out and made my own, otherwise the bottom of the trans would have hung below the frame rails.

I think it's likely that the problem is sloppy CVs or splines on the CV shafts, but that said, there are quite a few other causes of diff clunking. I wouldn't count out every other possibility without at least checking the CVs for slop. If there isn't any, then maybe this post will help:

Yeah, that's pretty much it. Stockish Z suspension sucks. The Z was competitive in Street Prepared until the E36 came into that class. Again, I don't keep track of the classes I'm not in, but that seems to have been the end of it. They might have demoted it to a slower class by now but I haven't heard of the good news about its renewed competitiveness and I'm in enough groups that I think I would have heard.

Sounds like FP. You might fit in one of the street mod classes. They came about after I was already committed to Prepared so I never paid much attention.

Street Prepared.

Prepared class allows extensive engine mods. Can't do a stroker, but triple carbs or ITBs, huge cams, crankfire ignition, etc all allowed. L24/26/28s are allowed in SP too IIRC. In all likelihood people won't care if your car is legal for a class unless you're racing with SCCA (people who run events seem to be hall monitor types) or you start winning. Once you start winning they'll look closer.

You'll need interior to run in stock or street prepared. Z's suck in those classes, BTW. With no interior you'll be in Prepared. L6 will go in FP, where the Z is still competitive but not likely to win anytime soon and it takes a lot of money to build a competitive FP car, or with an engine swap you'll be in XP, where you won't be competitive at all. If you want to win, you've probably got the wrong car to start with. I just figure out who I'm close to in times and then run against those people and have fun.

Same. If you need a set of insulators I have some off of a 240 that sat since the mid 80s so should be low miles. PM me if you're interested.

I've got some thoughts about that roll bar design: 1. Don't like the X up high. Too much weight, and you're reinforcing the strut towers with the top of the tube where it isn't very stiff. 2. I would do the backstays to the top of the strut tower. Plate that whole trapezoidal area and weld the stays to the plate. 3. The bars in yellow are great if you are connecting to door bars on the other side of the main hoop. Without door bars I think it's just extra weight to carry around. 4. If you want an X, you can do it low, from the strut towers to the bottom of the hoop. I did this on mine. Would be MUCH easier to install if you cut out the storage cubbies. I didn't. 5. I'd just go with a straight bar across the strut towers EDIT--Also connect the top of the hoop to the map light area of the roof with a shear plate.

Heh. Looks familiar...

IMO you need to consider the usage to choose a ratio. If it's just a street car it probably doesn't matter that much, but for a car that does drag racing you're going to want to be winding out a gear as you cross the line. For my use, autocross, I figured I wanted to be able to do about 80 mph at the top of a gear. 23.5" tire I was using with 4.11 and T56 puts me at 81 mph in 3rd at redline. Just going to start in 2nd and not use first at all.

Searching "chassis stiffening" might get some better hits. Link below. https://www.google.com/search?q=chassis+stiffening+site%3Aforums.hybridz.org&oq=chassis+stiffening+site%3Aforums.hybridz.org&aqs=chrome..69i57.7719j0j4&sourceid=chrome&ie=UTF-8 For my $.02, if you're only doing a roll bar I would weld a shear plate from the top of the hoop to the map light bar on the chassis. Had a friend who built a really simple 4 point bar with an SCCA legal diagonal and shoulder bar on his 240. He said after he welded the plate to the map light area his rear interior plastic pieces stopped squeaking when he went in and out of driveways. Made a very noticeable difference. On my 70 I really thought the front of the car needed a lot of attention. I could jack up the front on the xmember, set jackstands under the TC buckets, and literally see the frame rails drooping when I let the jack down, and hear it all creaking too. The chassis is pretty flexible at the firewall, apparently. If you look at the old Bob Sharp pics (which you can find here) they spent some time reinforcing the area between the door hinges and the firewall, presumably to help that issue. There are also tubes that people run from the rockers to the upper frame rails. I think these kinds of mods are worthwhile if you don't want a full cage. It's what a triangulated strut tower setup is trying to do, but I don't think the triangulated bars are very effective unless you beef up the area of the cowl that you attach to, which almost nobody does (except bjhines). Another one to look at is the cage that Dan, 74_5.0L_Z, did on his. It's basically how you would cage a convertible with no windshield. I really think he did a good job for a streetable car, where you don't have to worry about hitting your head on the A pillar tubes. I did a full cage and my helmet rested on the halo. Had to move the seat towards the center, will also probably have to lower the seat more or use a 20* seat, as I have a 10* in there now.

No, they don't. Please take the information provided in the thread and disregard the rest. If you look you'll see that Alan can be helpful, as in the linked thread about the Bilsteins, when he wants to.

Here's Coffey's post on the 46mm Bilsteins. I believe these are the shocks that he put on the the rally car in question: They were rather expensive as I recall.

No tech, but how about a 10R80?

One nice thing about John was that he'd say those things straight to your face, and since we conversed so often I'm sure I have seen most of them. You've still derailed the conversation from being about how to take a Z off road into how little Carl Beck knows and how your superior pedantry can solve the problem of how to set up a V8 Z for light duty off roading.

I can see how those pedantic details are germane to a discussion about a V8 rally/safari inspired build like the one the OP is building. Oh wait, no I can't. OP, you want to see something RIDICULOUS? Take a look at the bolt in roll bar that they used in those old works cars. I was ROFL when I saw one for the first time...

Carl Beck owns a rally Z, his email is at the bottom of the page I linked to previously. He's also on Facebook and is always willing to help. John Coffey built this one a few years ago. Unfortunately he died in a motorcycle wreck. Real loss for the Z community. I think he had some posts here about it, but my impression was that the biggest change was some custom long travel Bilstein struts. Had a pretty beefy skid plate and push bar, and the roof rack. I haven't talked to the owners of the car, but they don't seem like the secretive type and would probably answer questions you might have. https://www.facebook.com/p2p240z/

https://zhome.com/History/rally.htm