JMortensen

If you can fab up that tilt frame and the fender liners and all that, you could make a mold and do a FG version. It's tedious but not that difficult.

After seeing the frame underneath, my guess is that the two materials expand and contract at different rates, and it may be impossible to paint them together without it cracking. How about having a seam there and treating as two separate body panels? Other suggestion is take a mold off of it and do the whole hood in FG.

In my searching I've found 2 common vacuum pump setups. One is hardcore drag racer stuff where they use a big, powerful mechanical pump driven off the crank to put some serious vacuum to the crankcase. Runs about $1000. The other is to use a vacuum pump from one of the newer turbo cars that need it for power brakes. Newer Ford pumps seem to be the popular option, but they don't pull anywhere near as much vacuum. I still like the old drag racing exhaust systems as there is no pump at all, but they're not legal in basically any road racing organization in the US.

A bolt through the frame rail with a nut on top is not the best, IMO. Better is a plate on top and bottom, or top bottom and side with a tube welded in so that the plates are spaced properly. I went through a couple of revisions on mine but ended up with plates top and bottom and tubes welded top and bottom and nuts welded to the top and bottom of the tubes. Then I recently flipped the swaybar to the top of the frame rail because I was having issues changing bars with the splitter on. Now I can change the front bar out in a matter of 2 or 3 minutes.

tube80z has talked about doing this in a Z. Several people have run tubes in the rockers, so that has been done. A pillars aren't big enough to hide a tube, but you could stitch to it and cover it and that would work fine, I expect. The problem is the roof and the halo. You could get the tubes right up next to the roof and stitch them in directly too, then box it in, but it isn't going to be far enough away from your head to be "safe". Safe is relative though. Even without a cage I once smacked my head on the top off the door opening pretty hard with a helmet on and rang my bell a bit. Did a 360 at an autox and when the (slick) tires gripped again... whack! Wasn't serious, a couple ibuprofen took care of it, but it got my attention. If you're looking for safety though, there are better cars to start with!

I ran gussets from the hoop to the map light area and I did two vertical plates from the sides of the main hoop to the door area. Hope the OP checked helmet clearance before welding in that diagonal across the roof. I wouldn't fit in my car with that bar in place. Would have to do it the other way, then no passenger.

FWIW I think that spec of torquing until reaching the correct drag on the axles is BS. I know, heresy, it's right there in the FSM, but what is happening to increase the drag? Are you squeezing the spacer so hard that it's distorting? Doesn't seem likely, but that's really the only way that I could see it working. Torque specs for fasteners generally have something to do with the bolt stretching. I'd like to see a torque spec for these based on the size of the thread, not the drag at the hub.

I had so much oil in the catch can that it made me think part of the problem was just pumping too much oil up to the heads, so I bought a set of oil restricted pushrods with .040" orifices. Also picked up some valve covers with -10AN fittings off of ebay. Looked at my old catch can and it actually has 1/2 NPT fittings on it, so I'm going to buy some -10AN pushlok fittings and try straight venting again. If that doesn't work then I'll convert the can to vacuum and run a fitting back to the intake. Not sure what to do with the 3/8" line off of the valley cover. I've been told that I can run it to the intake but that basically creates a vacuum leak. Could T it into the -10 line and vent it, but it's a restricted orifice (not that easy to blow air through it) so not sure that it is worth it. Thinking T it into the vents and if I still have problems then I'll maybe remove it, drill a hole in the old valley cover and put a -10 fitting in there too. Most people seem to think that the bigger vents should cover it, I'm hoping that is correct. Will have to install parts and wait for spring (or dyno tuning) to find out if it worked.

Take it apart and see. I can't remember because it's been so long, but I can remember that taking the whole thing apart and reassembling is not a big deal.

Did a leakdown test today, engine is fine. Hooray! At first I just had the 3/8 lines from the valve covers to a vented catch can. Then I added the LS6 valley cover with the PCV. I haven't taken the stock valve covers off in years, so I don't remember if they are baffled or not, so in anticipation of this last autox I plugged them and ran the PCV from the valley cover to the intake and that was it. I bought a catch can but it showed up and only has 2 3/8" NPT ports, and I'm not convinced that I can vent all the pressure through a 3/8" hose. Thinking about returning the catch can and getting a different one and running -8 lines to it instead. Only problem is how do I get -8 to the valve cover and valley cover. Suppose I could drill and tap like I did the intake, but it's just another PITA. After looking at it I'm also not inclined to do a vented catch can. Think a sealed can to some source of vacuum is the best answer, whether that be intake or a vacuum pump or something else...

Well I changed out the valley cover for LS6 which has integrated baffled and restricted PCV. I plugged the valve covers and ran the valley cover PCV direct to the manifold. I have a catch can on order, but it didn't arrive in time for me to hit another autox. This one was wet and the car saw neither high rpms nor high g loads. After the morning runs with Mark Haag as a co-driver, everything seemed fine but we pulled the hood, and there it was: oil all over. Brand new part torqued to spec and everything. Borrowed a leak down tester from a friend. The motor still makes plenty of power, but thinking maybe blowby with load or something. Anyway will report back. Fast car driving slowly: <iframe src="https://www.facebook.com/plugins/video.php?href=https%3A%2F%2Fwww.facebook.com%2FJon.E.Mortensen%2Fvideos%2F2059742714072074%2F&show_text=0&width=560" width="560" height="315" style="border:none;overflow:hidden" scrolling="no" frameborder="0" allowTransparency="true" allowFullScreen="true"></iframe>

Interesting. I did replace the oil pump when I installed the cam, but I just put a regular pump in it. The PCV setup on the LS3 includes a valley vent which I don't currently have, so maybe that just adding that vent will make the difference, don't know. I'm getting the parts in hopefully today or tomorrow. If I can get them delivered and installed I might hit the last autox of the season Sunday and that way I'll know if the problem is solved before the winter downtime. Other option was to do a dyno day, but that sucks funds away from my fiberglass project for the winter (wing).

The car has only been out twice since the V8 swap, and this course was much more favorable to the high hp rear drivers so there was a lot more high rpm/rev limiter stuff going on. But yes, this is the first time this has happened. Course was about even right to lefts, maybe a few more rights, but not a lot more.

Thanks for that. I purchased something very similar yesterday. I'll post pics of the original setup and the new when it's all done.

Well, still working it out. Now thinking I might not have the fresh air vent at all, and instead route the valve covers and valley cover to the can then to the intake. EDIT--would have been one valve cover to the vented can, the other two PCV hoses T'd and attached to sealed catch can and to intake manifold.

Talked to David Carroll and we were both thinking this is a PCV issue. I think I have a fix planned. Upgrade to LS6 valley cover and then run the PCV to the intake with a sealed catch can to separate the oil. Keep vented can as air intake.

Had my Z out at an autox last weekend and after three high rpm runs my L33 5.3 started leaking oil out of the top of the engine, still not sure if it was valley cover or valve cover but it was all over the top of the engine. Question is for those of you who have road raced or autoxed: what mods have you done to get the oil out of the heads and back in the pan? What worked, what didn't, etc. Right now I have a baffled trapdoor pan and 3 qt Accusump and my PCV is just the hoses off the valve covers to a catch can with breather. I've been looking at drilling holes in the lifter trays, porting the oil return holes in the head, switching to later PCV (LS2 I think is the one with the baffle in the valley cover), seen return hoses added directly to the head and oil pan. Would like to solve the problem without pulling the motor if I can, but may not be possible.

The guy who did mine used that pic and calculated it out. He also owns a race shop that builds a whole lot of cages. Another way to do it is to bend conduit to shape and then bend the tube to match the conduit. That's how I did the halo and A pillar bars in my cage.

But that POS has a solid rear axle. Will never handle... Seriously, you're setting yourself up for a huge project. You would be a lot better off if you want track time to buy someone else's completed swap and then do the aero to it. If you are dead set on doing this all to your existing chassis, then we can certainly help, just a lot of $$$ and hours in it. "Best" kit IMO is Hoke Performance. It fits with long tube headers too: http://hokeperformance.squarespace.com/store/ For widebody I'd suggest http://www.ztrix.com. Their YZ is probably the most popular, looks fantastic. I really like the 940Z kit also, kinda sorta looks like 944. If you search "chassis stiffening" there are many threads on different peoples' cages. If you're going SLA front and rear that will mean that your cage will probably be a lot different than mine, for example, since I built the cage to attach to the strut towers. Data acquisition on a new car is so easy, many plug and play OBD systems out there. On a Datsun, you're going to figure all of that out yourself, which will be a PITA. There is a guy who took a Z06 and cut the torque tube and welded it together shorter, then modified the YZ kit to fit. It is amazing, handles like a Vette, has brakes and suspension like a Vette, etc. This might be the easy way if you don't mind mega fender flares. Do the bodywork, add a wing and a diffuser, and you're goals are pretty much met.

When I bought my current Z in 1997, I did it because it was a CHEAP, light, easy to modify autox car. In that order. Now that they aren't cheap anymore, if I were looking for a car to mess around with and modify/race, I wouldn't choose an S30. Probably go Miata, BRZ, or 350Z. The S30 downsides of rust, age, crappy handling out of the box, and hard to get/expensive parts makes it a loser for my particular purposes at today's prices. YMMV.

I had them done on my E31, didn't do it myself. No problems. If you think about it, a LOT of heat transfers from the valve to the seat. It wouldn't make sense for that area to be really thin.

Yep. Nicely done.

Agree with Richard. The huge attachment point of the upper frame rail and its connection to the the cowl which is a torque box is an important part of the already weak Datsun structure. If you're going to replace it there needs to be a load path, can't just weld a plate to the firewall and then run the brace off of that. Running it to the A pillar bar of a cage, which is then reinforced by door bars is a good way to handle it if it needs to be removed. Grannyknot's mod looks fine, but I would weld the original frame rail back to the tube that he added, so both are structural.

I signed up, then got into the Monroe autox which is 8 miles away and gets 14 runs, then it rained so I didn't go. What a disappointment.

That "put it back where it was" suggestion is a bad one even for a diff that has a crush sleeve. The R200 has no crush sleeve. The spec is RFT, I want to say it's something like 150 - 200 ft lbs. I always use red loctite on the nut the put my impact on 5 and hit it, empty the compressor until it fills, then hit it again. Never had any issues.