Pyro

going from 8.5 to 10:1 would be worth 10hp in your case. http://www.wallaceracing.com/hp-cr-chg.php this assumes you can still run the correct ignition timing, as all the gains would be lost if the ignition timing had to be retarded to prevent ping. curb weight is about 2850 lbs for a 280z, adding a v8 adds about 150lbs, you could drop 150lb off the car if you remove most everything. to find hp, run your car at the track. Use 1/4 mile trap speed and car weight to calculate hp.

try 26 degrees initial with 40 total. (just add 10 more).

where is the filler tube for the tank?

old heads are crap compared to the new heads out there. The best thing about a 327 is the 4 inch bore block which can be used to build a 350 or 383. I would keep the 327 complete and sell it to a "327 lover", then buy a complete 96 to 99 350 vortec truck engine with factory roller cam. There is nothing magical about a 327. A 350 or 383 will make more power.

you can use the 240 pan but you will need to use the 240 oil pick up tube and add a oil drain line from the turbo. I like the rear sumps because it allows intercooler piping to be run under the engine (between the cross member and pan sump).

big blocks need lots of timing, even mild ones. plug you vacuum advance into a manifold vacuum source (not a ported source). You need vacuum advance! set total timing to 40 (at 4000 rpm with no vacuum advance). would be nice to have 15 to 20 at idle, then get another 10 from the vacuum advance to make 30 at idle. This will make around 50 when you rev it up in neutral (no load). crane makes a vacuum advance that is adjustable. You will be surprised by the power difference if you make these changes. readjust the idle speed and idle mixture after the timing adjustments. You will find the engine smells much cleaner and gets better mpg and has better throttle response with more timing. here is a nice timing write up for a small black chevy. skip to the end of the paper to see what i'm talking about. BBC need more timing than a SBC due to wider pistons and slow flame travel. http://www.corvette-restoration.com/resources/technical_papers/Timing101.pdf

these work well on a Z V8 conversion. http://www.thezstore.com/page/TZS/PROD/7BSA03/30-7090 but point the opening forward, not to the rear as in the photo. The forward opening blows cool air down on the headers and really makes a difference with the under hood temps and the firewall temps. (I have tried it both ways and forward works much better). Header wrap works well also.

try more timing?

that is right, your 240 tach will not work with an electronic ignition system. A 5" Autometer will slide right into the stock tach location. No need to pull out the dash. a little cheesy, but a little black rtv will hold the 5" Autometer tach in place.

Every loud pump I ever had was caused by a restriction on the input side of the pump. Either the filter or intake tube. A walbro 225 needs a 1/2" feed line with a 100 micron filter of decent size. As a test, try it without the filter and with a 1/2" feed line directly into the tank (down the filler hose).

get a used and complete 5.3 from fan to flywheel with efi system. And get the transmission while you are at it. You should be able to get the complete engine with the trans still attached for 1200 to 1500 (the cost for a good set of sbc heads). building an engine piece by piece will cost a bunch. Trickflow has a 450hp 5.3 top end kit when you are ready from more power.

http://www.chevyhiperformance.com/techarticles/148_0401_chevrolet_406_ci_engine_build/index.html

Add a few more dynomax bullet glass packs in the trans tunnel area. Use perforated tube glass packs, not glass packs with bumps in the inside tube.

Pro's cheap durable (easy on the lobes, rockers, and springs) quiet extra 500 rpms Con's Maybe slightly less torque under 2000 rpm I have run a stock turbo cam, MSA stage 1 cam, and a stock NA cam all on the same engine and I prefer the stock NA cam for my turbo engine. I just drive it on the street.

I say, stay with the 400. http://www.chevyhiperformance.com/techarticles/148_0401_chevrolet_406_ci_engine_build/index.html or build a 350. easy to build a 7000 rpm 350. nothing special required to make a 350 sing: proper part (heads, forged crank, balanced, valve springs, cam, and rod bolts) and a 350 will rev like crazy. 327 is a worthless engine with a cool name. imo. Why spend more money on a 327 that makes less power than a 350??

A few weeks ago I pulled out my msa stage 1 turbo cam and went back to a stock NA cam. My engine pulls hard to 6000 then falls off. It will make 6500 in first and second if I'm slow to shift. Stock turbo cams stop pulling around 5200. You should be boosting sooner with the stock 0.63 turbine. Maybe you have something wrong with the tune or the turbo. Full boost by 2700 should be about normal. 8 or 9 psi with a stock engine and IC should be about 200 to 210hp.

max inlet let is almost 0 psi with a stock efi pump and a return line. get a tee and a pressure gage. loop the gas back to the tank with the return line and measure the pressure at the tee. It will be near 0, maybe 1/2 psi. If your regulator isn't "bypassing" then it is not working or it is not connected correctly.

you need to set the engine back in the JTR position if you plan to use the T5 trans. The JTR engine position put the T5 shifter in the stock shifter location.

A friend of mine has a daily driver 77 280 with a 350. We have being trying to cure the extra hot firewall issues for a few years now. What works the best is to replace the stock hood vents with MSA scoops. But turn the scoop openings to the front so cool air will be blown into the engine compartment. This made a huge difference in the temperature of the floor boards and firewall. The scoops are designed to have the opening facing the window, but they didn't have any cooling effects on the firewall in that position. But lucky they are reversible.

use a return style regulator with the stock pump and stock return lines. aeromotive makes a nice one for $125 that can go down to carb pressure (5 to 7 psi).

msd-2225 efi pump will work. so will a z NA efi pump. I would bench test the pump with a 5 gallon gas tank. pull gas from the tank with the pump and pump it back in. I bet the tank is rusted up. http://www.summitracing.com/parts/MSD-2225/

Yes, I'm aware of quenching. But, for a street L28 engine with flat tops and a P79 or P90 head it will not make any difference you will ever notice. what I'm saying is you are over engineering your engine. Get a felpro and go. The L28 flat top build with a N42/N47 head makes 10:1 cr and has very little quenching due to the poor chamber design and it works well. I have never had any issues with felpro's. Make sure the surfaces are clean and flat and they work great. even with boost.

would try to keep the engine and trans together and use everything to can to keep it "as it is" in the 92 now. will need a power steering delete kit. later now you can increase the power of the 305 with better heads and more cam.

I got a garage full of new and used felpro head gaskets for Z's and they are 1mm (0.040") thick. I never used a nissan head gasket, but hear they are 1.25mm. 1mm or 1.25mm is not a big difference, I can't image it would make any measurable difference in performance.

I would worry about the cam later. much later get your engine installed and running with IC and 12 psi drive it for awhile then worry about the cam, as you have bigger fish to fry!