Get a 350 with vortec heads (97 truck engine's are good for this), install a bump stick like the XE262. With 1.5 rockers you won't need to machine the heads and you can get away with the stock springs if you keep the rev limit below 5600.
Walbro 190(255)lph fuel pump , performer(RPM) intake, adaptor plate, bbc injectors (don't need the 2" bbc TBI unit, just injectors), make stock FPR into an AFPR, REPLACE the FPR diaphragm, set pressure to 20psi, 3.42/3.73 rear gears, get the g2&burn1&AT29C256 from moates.net, use TunerPro tuning software w/WinALDL or EBL, tune it, and go to the track. If you don't run 13's you've got something mechanical wrong. You don't need a high stall TC with the 700r4/4L60 when you do gears. The reason for this is that you won't spend much time if any below the stall speed and you'll be running in the 13's with street tread!
This is a fool proof method so long as you don't discredit your own tuning skills. Learning to tune isn't difficult, it just requires persistance. If you gave up on learning years ago then I can help you out but I'm not free when you meet me in person... my online help IS free.
So anybody can do the above for between $1500-1800 average. Shop around and you can do it ALL for less than $1000!!! Add a little nitrous and get those 12's
Did I forget anything?
Almost forgot; the above should have no trouble passing emissions testing so long as EGR isn't a visual inspection. If that's your case it will cost a little more to add EGR or get some standard sbc heads with some port work. You could even port the swirl port heads if you had the patience.

 

JP,

What FP diaphram do you recommend? I am afraid my stock on is on borrowed time with the Walbro pump. This has also been a big debate when using the 255l pump with the stock diaphram.

 

Whatever comes in the rebuild kit that you can buy for around $28. You need to be very carefull with it. One little poke or scratch, even if it's not a hole, can cause it to fail. I just replaced one on a buddy's car at the drag strip. We drove all the way up to pop the hood and see fuel flooding the top of the TBI. It was coming out of the regulator sight window. 255lph pump, bbc 90#ers at 17psi. The hole was SMALL. I've got great near vision and it took me a while to find the holeS. 2 or 3 small tears near the metal spring seat. You could only see them by pulling on the diaphragm.
This diaphram/setup was a old used j-yard part because we were in a rush to get the thing running.

 

I wonder why the rebuild one is so much stronger?

Thanks for the heads up.

 

I don't know if it is but it's new!
My main concern is that people go and make their fuel pressure regulators adjustable and then reassemble everything with the old worn out diaphragm. Don't cheap out, just get the rebuild kit and sleep well at night.

 

I have an old ball TB so I don't know i its the same as other late 454 tbs, but it was made to run at 30-40 psi and the diaphram is thicker and is the same size as the lower pressuer ones.

 

That would be the 94 and 95 454 TBI's.

 

Yep, I just bought that pump to service my TB at 20 psi. The stock part number can't even reliably hold 14 psi.

 

Mine came off a big cargo truck and had a BIG govener cast on the side of it.

 

That's the 94-95 454 TBI. They are the only ones to have the goveners built into the TBI unit.

Does anybody have a picture of these diaphrams? I'd really like to see them and then if that same person could get a picture of the regulator taken apart that would be awesome.

 

I've got my old regulator lying out on my welding table, but no diaphragm since I reused mine. And yeah, I know, but I couldn't find a kit that had the diaphragm without getting raped by the dealer. Every parts house kit I talked to, including having a $40+ Delco kit shipped in, had no diaphragm.

And one other thing not mentioned, the stock diaphragm has 2 layers, at least mine did.

Anyway, I can get the picture of a housing if anyone cares and nobody can provide both.

Also, is there any source/part number for that stronger diaphragm? Preferably without a kit, but I would get another kit if needed. I'm really leery of that old, worn diaphragm when I turn up to 20 psi, even though it looked very good.

 

You think you guys have it bad with the cost of rebuild kits... check out what Holley wants for their 503-5 rebuild kit. It does come with everything but it's $44.69 from Summit. Buy 2 kits and I could have gotten a real aftermarket bypass style EFI AFPR!
Mallory makes some nice inexpensive regulators for under $100. I think there is a 4-25psi and a 30-100, just what I need for running 28psi . I wouldn't bother with this but I'm replacing my fuel lines so I figure do it once, do it right.

 

O'reilleys has a borg-worner rebuild kit that has all the replaceable parts. It also has extra gaskets to raise the TBI pod up. They have different thicknesses for all TBI's but they are the same size. The kit is about 45 bucks, but for a TBI spacer, and new diaphram, new screens, gaskets, ect.. it is worth it.
I just didnt know that the diaphram would supress the higher pressure. Isnt a new spring needed? My rebuilt regulator was only good for 14 psi, but the pump only put out 16psi.
The higher pressure pump also need to have a bigger return line. If not the line becomes a constant FMU.
HAPPY THANKSGIVING!!

 

Wrong. The return line doesn't raise the pressure because it's small... take a look at the internal passages of the TBI unit, they are the major flow restriction, not the return line.

 

A late model TBI rebuild kit should also work. Although odds are the price will be about the same.

Ive yet to replace any of the seals or the regulator diaphram when Ive disassembled, but after so many disassemblies, Ill probably have to replace the o-rings since their so stretched out.

 

I didnt know the late model diaphrams where thicker. Ill have to try and get one.

 

And what kind of MPG are we looking at with this setup?

. . . even if it is a little late for me, just curious. My setup is a little more built than that. Still tuning. . . still destroying trannies.

 

My educated guess would be 22-24 highway with 3.42's and a lockup converter. City would be totally dependent on the converter and how good you are at tuning. I bet a <2000 stall with lockup in 3rd could manage 14-20 city. My 2800 stall managed 14 average 90% short trips (less than 5 minutes) in the winter! So look at around 20mpg if everything else is in good working order (tires, alignment, tuning, sensors etc.)

 

I'll take some pics of both stock type diaphram and a holley one this week end if I get the time.