pparaska

I agree the lobe center opening up by 1.5 degrees helps, but it doesn't offset the added duration (8 degrees wider on the intake and exhaust both) and your overlap goes up by 5 degrees (according to Desktop Dyno's Cam tool). That'll raise the power band a bit. I can't imagine what that thing is going to feel like when the cam comes on and the turbos hit! I hope you have one hell of a drivetrain and tires behind it? (Or maybe let the tires be the safety valve!) You probably already need to have your head against the seatback in preparation for the boost hitting! I'd love a ride in that thing!

In a few weeks or a month when my car gets back from painting, I'll shoot a ton of pics and put them on my site, including the roll bar install. Round tube should work, but I pie cut the rectangular tube, bent one wall, and welded it back together, using double plates at the cut. Easier than bending round stuff if you don't have a bender. Actually, it would be structurally better to have the 3" wall vertical, but that would take away precious ground clearance and/or foot room.

Craig, is this what you're looking for: I went through something like this. Take a look at: http://members.home.net/pparaska/structuralmods.htm I also added a roll bar with tubes tied to the strut towers, the header in front of the hatch opening, and the tunnel. I also went without door bars, so I think what I did may line up with what you're thinking. HTH,

For a motor of that size, isn't 230 @0.050" valve lift pretty big? Hell, that's on the edge of what many think is streetable on a 5.7 liter motor. (Of course, street may be of no concern here.) This is assuming that the "smaller engine, less duration" rule of thumb holds. 8 degrees is not a small amount (230 vs. 222) on a 5.7L motor, and it's even more significant on one half as big, I'd think. If it were a normally aspirated motor, I'd think this cam would be peaky, up above 4000+ rpm being the bottom of the powerband. Will the Turbos negate the large duration effect? Sorry, I'm pretty clueless about camming a turbo motor, but I thought that less duration (on the intake at least) is needed for a turbo motor, and overlap should be avoided at all costs. Would more lobe separation be better, if you were concerned with low and mid range? Note, the above are more questions than answers. That cam ought to be a monster on the top end with two big turbos!

lenster, yeah, you can tell by looking. Me too. If I was building a bad 69 Camaro, It'd have a BB in it . Always liked that body style. If it was a 70 Cuda, it'd be an RB or Hemi - probably just settle on the 440 . Of course, I've got a special place in my heart for 427 Cobras and 428 SCJ GT500 Shelby Mustangs - had a ride in the former lately, and had buds with the latter in High School! Fun stuff. I'm an equal opportunity car guy. Chevy calls there BBs Mark IV. Then the smallblocks are now called Gen I, Gen II, Gen III. Those are pretty much determined by when they were built, unless you have an early racing Gen III, I think.

I have a write up on this conversion at: http://members.home.net/pparaska/280zxreardiscs.htm Note that Ron Tyler no longer offers the brackets. One thing to mention is that this conversion likely will interfere with many wheels at the "yoke" on the caliper. I had to machine that yoke down to let it clear my Western Hurricane wheels I had at the time.

BLKMGK, on the 240Z, the black w/ yellow strip wire that used to go to the starter engage terminal (blade) goes to the small "B" terminal in the pic above. The stock solenoid still is used - it still needs to pull in the bendix and gear to the flywheel. You need to run a wire from the large terminal on the starter solenoid where the batter cable attaches to the small terminal that the starter switch usually activates.

I've been bench racing, reading, and participating in the V8 performance scene for 25 years and everything that Night_rider_383 said above rings true. What I don't understand is people putting tons of money into a total engine package (including EFI, etc.) and "saving" a few hundred dollars by going with cast pistons. For a few hundred dollars (if that) over cast or hyper pistons, you can get the excellent detonation resistance with a forged set. This is the beauty of the American V8 engine - the hi-po parts are not much more than stock replacements. Try THAT on an L6! I say buy those forged pistons for the detonation insurance they buy you - you never know when you might get a NOS system cheap! I understand that if you buy a cheap crate motor you don't have this choice, but if you're having it built or building it yourself, why not spend a few more dollars on forged pistons? I also agree on the cam type issue. For the under 500hp street motor, I don't think you gain much from roller lifters - especially if they're the heavy designs some of the companys have for hydraulic roller lifters. The flat tappet cam grinds available today give you all but maybe 1-3% of the torque under the curve that's what needed on the street. Sure, that roller setup saves a bit of horsepower, and might have a smidge more torque here or there in the entire rpm range of the engine, but most engines aren't tuned well enough to find that torque anyway. Just my opinions,

I think it was said above somewhere but I think the answer is simple: Manufacturer A develops a V8 in the 50s. It's known as their V8. Then manufacturer A decides it needs a bigger engine (with the casting technology (minimum wall thickness) of the day) and develops their "Big Block" V8. The original smaller engine is then known as a small block. I believe this is what happened at Chevy, Ford, not sure about Mopar. I think others (Buick, Olds, for instance) started with larger blocks and went smaller (or used the Chevy SB in their cars). I think it really comes down to the manufacturers coming up with different sized engines at different times and the names being given to differentiate them. Remember, when the BB Chevy came out, the small block was only 327 cu in. (maybe only 283, not sure when the BBC came out). [ May 30, 2001: Message edited by: pparaska ]

I remember reading that you should run the sensing wire to the positive battery terminal. This is so that the sensing wire sees the voltage of the battery, which is probably a bit lower than that of the alt output, since there'll be some resistance and voltage loss from the alt output to the battery, if anything but huge wire is used for this. The idea being if you reference the sensing wire to alt output, the battery will never fully get charged. Hope that helps.

Don't have my car - it's at the paint shop - or I'd measure it for you. I think the cross section on my 2.5" pipe version at the center was oblong, probably an ellipse with a 2.5" height and 3.5-4" width.

Yeah, the channel carries the load better than just a plate - it's taller and doesn't depend on the probably rusty "side" of the stock rail. Being an engineer, I'll take that comment about "re-engineered" as a compliment . My car is really more of a hobby than a car. It's provided many years of tinkering enjoyment . I can't wait to drive it though! Should be painted in a few weeks. Cheers,

Owen, I can't get to your site right now to look at that spoiler (homestead says no such page). But the BRE 1-piece is a bit different than the 1-piece "432" rear spoiler that Classic Datsun Motorsports sells. I have that piece on my car. I prefer the tapering contour on the ends of it to the BRE one, but not by much . The BRE one is a bit taller. Note that they also have the bolt on rear flairs.

Mike, I think we need to talk. That Vic Jr. I'm getting from you may get a few injector bungs in it... Who does this cheap?

The one I have from Dr. Gas looks like two press bent (I know they say they're mandrel but they look press bent to me) 90s. If you're making your own, lay out the exhaust first and make the angle greater than 90. It was difficult to turn out of the Dr. Gas piece and keep the pipes in the tunnel. Just make sure that the divider created by the two pipe bends coming together is in the center, when looking at the inlet of each bend. This is so you get a good split of the exhaust pulse from each inlet. If you can weld decently, this part shouldn't be hard to make. I was real surprised at the product, considering $90 for just the X-pipe union. I think you're better off making your own, especially under the Z in that tunnel. BTW, I love the sound the X-pipe gives! No idea if I'd ever be able to tell the power/torque difference if any.

Curtis, I did one better. Since my frame rails were swiss cheese due to rust, I replaced them with some I made out of 2.5"x2.5" tubing. Before that, I took a piece of 14 gage steel and bent it into a U that fit over the portion of the rail just forward of the crossmember, all the way to the rad support. The bottom of the "U" was on the inboard side of the rail, and the sides of the "U" were on the top and bottom surface. I welded the periphery of the part, and had a number of holes in it to plug weld to. Not much to weld to in my case, in several places. This also allowed me to redo the anit-sway bar mounts with big welded in nuts.

Jim, I agree. Since the valve is going from 0 lift to full lift in the same amount of time (at a given rpm) and the lift is obviously more with the higher ratio rockers, the peak velocity and acceleration will increase. But the increased valve train flex may lesson that. Good point, hadn't thought of that before - thanks!

Of course, plan the entire car out as best you can, with the budget alotted. Some of us don't do this and get carried away . Make sure that the brakes and suspension can handle the horsepower, but first make sure the shell is up to it. If you plan on big power, subframe connectors and a roll bar/cage are in order. Get the shell squared away first, and the rust dealt with. Design the brakes, suspension, and wheels together. Decide on what wheels and tires you'll run, and this will probably drive you down a road to a solution. If you want big meats under stock fenders, then plan on coilovers. Look at what people have been doing lately for wheels and tires. 17s in a 4 lug pattern for wide wheels (8+" width) are custom, if even available then. Consider Mike/scca's 5 lug conversion. Then be looking at his brake packages. Motor and trans, sky's the limit. Get the JTR book if you don't have it, and read lot's of old articles here if you haven't. If you want a manual, the T-56 is sweet. Find an R200, and swap that in. Good u-joints or go with 280ZXT CVs. You can do that swap easily with the 240Z stub axles, but those are the weaker design. May not matter if you're not talking insane power and use. Most people do the bodywork last. I did everything at once (I know, over many years . Hope that Helps,

Lone, what you're seeing there is the side of one of those Chevy rubber mounts that are in the radiator brackets in those cars. Not sure what car it came out of, but it's GM. See the little hole in the center, front to back? That's actually the little rubber tit sticking through a hole in the upper mount, holding it from falling out or moving left/right.

Nice looking Z! The paint and body look pretty nice in those pics!

Jamie, cool, sounds like the same thing that Mike Kelly did. His was one the inner fenders but he's certainly changed it since then!

quote: Originally posted by Michael Jackson: ...The rocker arms will affect only lift and not duration. Jack Not totally true. Look at it this way. The lobe on the cam is the same. With the 1.5 rockers, the cam has to move the lifter up 0.0333" to move the valve 0.0500". For that same cam with the 1.6 rockers, the lobe has to move the lifter only 0.03125" to move the valve 0.0500". Assume that all the "significant breathing" is done above 0.050" valve lift, you can see that the cam is moving the lifter a little bit less (and this occurs at an "earlier" angle) to get the valve 0.050" off the seat with the 1.6s vs. the 1.5s. It also turns farther to get the valve back to 0.050" off the seat near closing, with the 1.6s vs the 1.5s. This is why you get a bit more duration as well. Not to mention the area under the curve from the using the 1.6s, from 0.050" off the seat (opening) to 0.050" off the seat (closing). The cam has to turn throught more degrees to get these "opening" and "closing" lift points, and the max lift is larger as well. Personally, I think it's better to just get a cam that has the correct profile and max lift, and use the 1.5s. If anything, use 1.6s on the exhaust to experiment with "splitting" the cam more than it already is. Using 1.6s on the exhaust (and 1.5s on the intake) make the exhaust lift and duration increase over what's ground into the cam and may help fix a strangled exhaust port, etc. But I think the Edelbrock heads are pretty decent on the intake/exhaust port flow ratios anyway. I think if you want to spend some money, and think your vavle action isn't what you want, just buy a different cam. Oh yeah, another thng to watch for when putting larger ratio rockers on is valve to piston clearance, as well as that excellent list that Michael Jackson put up. [ May 27, 2001: Message edited by: pparaska ]

The only wire like that I can think of is the Big (10 gage) white or wite w/ Red strip wires that come from the starter and the alternator (forget which goes to which).

Jim, the upper left fan mount you see in the picture, I jus used a piece of 18 gage steel and bent it. The piece is epoxied and bolted in place. The other side that you can must barely see is more complicated, a flat piece epoxied and bolted to the fan, and tab welded to it (before putting on the fan ) with two gussets from the tab to the flat piece. Hope that helps,

Mike, it really is subjective, and that was the car I was referring to. Of course, I've never driven yours! I guess it really depends on what you want too. I know that too much anti-sway bar can be no fun on a curve with rough pavement, etc. So I decided to start out conservative and go from there. Something tells me I'll get used to it, think it rolls too much and upgrade .