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Bryan, Just curious, what brand cap / model number is your cap? Joel

Today I got a chance to talk to both Palco and Accu-Form. Here's what I learned. Both companies use roughly the same mold, which is not too surprising, considering that two former employees of Accu-Form formed Palco back in the late ‘80’s or early ‘90’s. The man I spoke to at Palco (Dashtop) told me he has been producing the same cap for around 20 years and has had no complaints regarding fit on the 280Z. He used to produce two products for the 280Z, the 303D and the 303. Originally, the "D" version had a deep return and the standard 303 a shallow return (referring to how far the cap extended into the gauge openings). These days he only produces one cap for the 280Z, the model 303. Today's 303 is different from the original 303 and is somewhere between the original 303 and 303D. Next, I called Accu-Form and spoke to a woman named Tammy. She was extremely helpful and quite knowledgeable. Tammy told me that Accu-Form still produces both the standard (303) and deep (303D) versions of the cap. When I explained my problem to her, she told me that she had another customer a couple of months ago with exactly the same problem. The solution was to switch to the shallow cap, which went on without a problem. She indicated that in addition to having shallower returns back to the gauge faces, the standard cap has slightly different dimensions (probably just a difference in mold tolerances) that allow it to fit better on some dashes. She was going to ship out a standard cap today and issue a call tag on the deep one. Hard to beat that kind of customer service! I don’t know if Accu-Form sells direct, but I purchased mine through American Dash Caps, who also provided excellent service. I should have the new cap by the end of the week. I’ll let everyone know how it fits as soon as I get it. I hope that this will help Bryan (LBO730) and anyone else with a similar problem.

Yours fits way better than mine! When you ordered yours, did you have an option to specify a deep cap, vs a standard one? The fact that your part number doesn't have a "D" tells me it is probably a standard cap. This may be my problem. On mine, the gap between the edge of the cap and the dash, is about 3/4-inch at the bottom edge, just below the knobs. When I get a chance tomorrow, I'm going to take a couple more pictures so you can see in detail what I'm trying to describe. I'm also going to call Accu-Form and see what they have to say. I was under the impression that both Palco and Accu-Form used the same original molds, but I may be misinformed. The part number, 303 is the same for both companies, which is kind of a strange coincidence. The "D" supposedly signifies the deep cap. I really hope I'm wrong, because in that case I'd return my Accu-form and purchase a Paco in a heartbeat! When I talk to Accu-form, I'm also going to ask for some clarification on the difference between the deep (303D) and standard caps.

The car has no hidden damage and the dash is not distorted as far as I can tell. In fact, the dash is in good shape except for the top. I would use a half cap, but the PO used screws to hold the bottom of the old cap in place, so there are screw holds in the bottom portion of the dash that would show if I used a half cap. I think the shaft openings for the dimmer and odometer would like up if I could somehow get the cap to lay flush. I've included a picture showing how the original cap was installed, which might give a better idea of my problem. As you can see, the PO just put the cap over the knobs which is make them useless and looks bad. This particular cap and the one I replaced it with are referred to as deep caps. In other words, they cover more of the area that returns back towards the face of the gauges. I'm starting to wonder if I might be better off with a standard cap that has shallower returns. It really shouldn't matter, if the caps are made correctly, but there must be a reason they offer two styles. I think I'm going to give Accu-Form a call tomorrow and see what they have to say about this??

A while back I purchased a restored 1978 280Z. The car looks great, inside and out, except for a poorly installed full face dash cap. The cap fits well, except in the area around the trip odometer reset and dimmer control knobs, where it gaps by almost ¾ inch. In fact, it fits so poorly that you can’t even install the two knobs. This has been bothering me ever since I received the car, so last week I thought I'd remove the existing cap, prep the dash properly and install a new one. I had no problem removing the old cap, as the double sided tape used to install it had long since lost its grip. The dash was in bad shape as I expected, but I really couldn’t find any reason why the old cap fit so poorly. In particular, I couldn’t find anything that would keep the cover from conforming to the area around the odometer and dimmer knobs. I cleaned everything up and purchased a new cap from Accu-Form (the old one was manufactured by, Palco). When I received the new cap, it looked nearly identical to the old one and in fact the part numbers were even the same, 303D. When I went to install it, not too surprisingly, it fit, or didn’t fit, nearly identical to the original. Just like the original, it fit perfectly everywhere, except around the odometer and dimmer knobs. I’ve had the cap on and off a dozen, or more times and I can’t figure out what’s wrong. From what I can see, no amount of trimming or finessing is going to help. It’s almost like the cap isn’t formed correctly. I did some research and it appears that some of the older Accu-Form molds may have come from Palco. I’m starting to wonder if there may be a problem with the 280Z mold that Palco and Accu-Form are using. If there is anyone who has recently purchased / installed a full dash cap on a ’78 280Z, I’d be interested in how it fit, or what you had to do to make it fit. Also, I’d be curious who the manufacturer was and where you purchased it. I’d like to try a cap from a different manufacturer, as I suspect that Palco and Accu-Form used the same mold, but as far as I can tell, Accu-Form is the only company still producing full coverage dash caps for the 280Z. Any help would be much appreciated! Thanks.

Coz - Thanks - I'll head over to Hybrid-Z and check out the Megasquirt info. It's funny you mention motorcycles, because that's an area I'm more familiar with. My go fast days are behind me and now I'm more into LD touring. I currently have a 2000, BMW R1100RT with a EFI built by Henry Ford! I'm also considering an aftermarket ECU on the bike to eliminate surging (runs way too lean), but somehow that seems simpler. Maybe if I start thinking of the Z in motorcycle terms it will make more sense.

If I understand what you're saying, all that would be required to install the Megasquirt would be to install an O2 sensor along with an intake air sensor. I understand what it takes to install an o2 sensor, but I'm not sure what type of air temp sensor you're referring to. Would this be the same type of temp sensor that is part of the AFM? Where and how would it be installed? As you can see by my previous post, this engine has extensive mods that might make it worth the effort to replace the ECU and do it right. The more I think about it, going back to stock would be a waste of all the work the original owner did. FWIW, the car has never been raced and has less than 5,000 miles on the engine. Thanks.

Thanks for the help. I don't want to race the car, but on the other hand to take it back to stock would probably cost me just as much as upgrading the ECU or replacing the injectors. I'm kind of on a journey here and I've got to figure out if I'm closer to home (stock) or my final destination (finish the mods). As it is the car is probably closer to a race configuration than stock. In addition to the mods I've already mentioned, the engine has been bored 30 over, has a balanced crank, stainless valves, hardened valve seats and springs, ported, polished and matched intake, 3" exhaust headers - tail pipe, custom drive train mods and etc. With that thought in mind, I think I'll take your advise and upload my original posting to the HybridZ forum. Thanks everyone for the ideas and suggestions.

In answer to the last part of your question, “As far as you know, did the engine ever run correctly with this configuration . . .” I really don’t know for sure, but I suspect not. A bit of history may help. I purchased this car, sight unseen, off the internet (yea, I know, big mistake). Originally, about 10 years ago, the car underwent a complete restoration, including extensive under-hood modifications. In addition to the cam and fuel system modifications, a large bore throttle body and 280ZX AFM were installed at the same time. I think the guy who owned it at the time was more interested in winning car shows than having a reliable driver. In fact, between 2000 – 4 the car won several awards at various So-Cal shows. Back in the day, we used to say, “If it don’t go, chrome it”. I think that may have been the case here. As far as the ECU is concerned, I understand what you, Jim and Coz are saying. In fact I looked at the Megasquirt, but I wasn’t sure how it would work in my case, due to the total lack of sensors on the ’78 280Z (MAP, O2, etc.). At this point I starting to wonder what I would gain if I just went back to the stock injectors. I assume the ones you linked to on your last post are basically stock.

I am far from an expert when it comes to fuel injected engines, but I thought one of the functions of the pressure regulator was to reduce the fuel pressure to the injectors while the car was at idle (high manifold vacuum). In other words, given a certain pulse width and slope at the injectors, lower fuel pressure would result in less fuel being delivered the cylinders and a leaner mixture. As far as the temperature sensors are concerned, been there – done that. I do not know how a stock 280Z behaves, but in my case if the connection to the water temperature sensor feeding the ECU is removed (open circuit), the engine goes so rich that it will barely run at any throttle setting, much less idle. When I first got the car, it would intermittently stall while idling, just as if someone had turned the key off. After checking everything from the coil to the fuel injector relay, I discovered that the Bosch plug at the temperature sensor, had a broken / intermittent connection. After replacing the plug and substituting soldered connections for the bullet connectors, that problem was resolved. The start injector has been removed, so the thermotime sensor is irrelevant.

I recently acquired a 1978 280Z which incorporates a 512 / 300 high lift, long duration cam. In addition, the engine is outfitted with a custom fuel rail and high flow / pressure injectors (29lb). The original fuel pump has been replaced with a unit that has a deadhead pressure of approximately 100lb. The problem I’m having is that the fuel pressure regulator is a stock unit. Among other problems, it is incapable of dealing with the high pressure and low manifold vacuum at idle. The biggest problem I’m having is that due to the high duration cam, the vacuum is less than 5 in-Hg while idling. As a result the regulator senses that the car is accelerating and causes it to run so rich that it will barely idle without stalling. If it does stall it totally soaks the plugs and makes restarting extremely difficult, or impossible without removing and drying the plugs. I know there are several adjustable / programmable regulators available, but I’m not sure how they get around the low vacuum at idle. This must be a fairly common problem, as there are a lot of performance cars with radical cams, but after a whole lot of searching, I’ve not been able to find a solution. Any help or suggestions would be greatly appreciated. Thanks.

I'm new to this forum so I hope this is the correct area to post this question. I just purchased a 1978 280Z with extensive engine, drive-train and suspension modifications. I need to find a shop in the Chicago area (north burbs preferably) that is experienced with this type of car and performs quality work. I prefer small specialized shops over large assembly line type operations, but I'm open to all suggestions. Any help would be greatly appreciated!