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It's 100+ deg again today, the car is running really bad at higher RPM. I didn't want to thread jack the octain thread, so here we go.

I just ordered a Holley blue pump with a regulator to replace the pogo pump. This is about the last thing I haven't tried among the common remidies like insulation and heat shields. I thought about cutting the hood, but I have never seen a hood scoop that looks as good as the solid 240 unvented hood. My hood has a dent, but my body man says his father's a TV repairman and he has the ultimate set of tools and he can fix it. (thats for the old guys out there) So I figure that if I must cut the hood, now is the time as paint is coming soon. Any of you guys done a hood scoop (other than the Nissan part, not too keen on them) that looks like something? If so pics please. I was thinking that a Mustang cobra scoop might be a candidate, but it looks like alot of fitting work. That would look sort of like the old big block Vette hood, sort of. (no Klingon pics please)

So, back to the holly pump, I'm a little afraid that the pump might blow by the SU floats and spill raw fuel in the engine compartment. Has anyone put a catch can on your SU bowl vents? If so what did you buy or make and where did you install it?

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The Holley pump that I used has a red label on it (For what that is worth.) I mounted it back by the fuel tank, and have never had a problem with fuel spillage from the carbs. I assume that the return line must be working...

I have electric fans that run off of a thermostat I installed in the carb heater line. I generally don't have any issues with vapor lock. I haven't driven the car much in 100+ degree F temperatures, but just because I don't like sitting in a pool of my own sweat.

If you have enough pressure and flow from the pump then enlarge the orifice in the tip of the return line on the fuel rail to get more "cooling effect" (heat extraction) from the fuel that only passes through the rail and back to the tank.

Funny, I just fixed the vapor locking problems on my 260Z. It was missing the insulation on the fuel line going to the front carburetor. I bought some Vulcan Fire Sleeve and slipped it over the fuel line. I drove it around in 90++ degree weather with no signs of vapor lock, despite the issues it had when the weather was 20 degrees cooler. What type insulation did you use on the fuel line?

post-17662-1415081946617_thumb.jpegI would punch some louvers in the hood (and inspection lids as well). I have this on my Scarab Z and they really do a greatv job of venting the heat from the engine bay. They also do not spoil the lines of the 240Z hood. Just my opinion.

Walter, I have considered the fan idea, but haven't yet found a fan setup that looked like it would be both ellegant and trustworthy.

Blue, great idea, as usual, I will be sure to add that modification when the pump goes in.

Steve, I used a ceramic wool, wrapped in FG mesh (header wrap) held in place using aluminum tape with the reflective side out. The fuel rail is isolated from the head and mounting hardware using pheonalic washers. I can't see how I could better protect the rail from heat.

Scarab, I haven't looked into the louvers, but it is a good looking alternative.

Thanks men!

IF I get a vote, I think the scarab idea is brilliant. If you have to modify a 240Z hood, why not go something the old school datsun guys did.

Popping at high RPM is an issue that is near and dear to my heart. Lets just say that it could be a GREAT many things.

Fix the easy ones first. Then after you go freaking nuts, buy webers. HAHAHA

I got my pump today, it will go on this evening. I know the carbs are set up right because when the temp hits 97 to 100 degrees is when the problem starts. If I pop the hood at speed it goes away. I'll see what the pump does, It's not supposed to get hot enough this week to be an issue, so time will tell.

Okay, so I had to waite till today to do the install as I had to order the gauge for the regulator.

The pump is a little bigger than it looks, the only nice place to mount it, and have room for a high quality filter, was on the bracket that the jackpot mounts to. I was having a hard time manipulating the mounting hardware on the back side of the bracket around the moushtash bar and such, so instead of drilling and bolting I used two beam clamps to mount the pump, it works really well.

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I put the regulator up in the front corner on the inner fender which makes all the hoses as short as possible.

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So I presurized the system and checked for leaks, it's all good, started the car and adjusted the pre mechanical pump regulator to 3 to 4 PSI and let her run for a while to make sure the bowls on the SU's were not overflowing, again, all good.

So now I wanted to see if Blue's idea of inlarging the return restriction was necessary. I removed the returne line from the fuel rail and put a quart glass jug on it, I turned the pump on with stopwatch in hand, the electric pump alone pumps a quart in 8 seconds thru the return pipe. So thats almost 2 GPM and I think that should be plenty of bypass to combat the vaporlock, so I'm gonna reserve the drilling of the rail as a last resort.

I'll report back on the next hot day.

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