I am sure I could not afford it right now. I am throwing around ideas because obviously I am going to keep the car, and I don't want it to sit and rot.
I am NO expert, so take everything I say with a grain of salt, please.
After picking knowledgeable people's brains on here and on the slant-six dot org site, I have, nevertheless, formed some opinions that may or not be right.
Here is what my hundreds of hours' research has "taught me."
Number one: A 170 cubic-inch slant six is a
wonderful race motor for those working within the confines of an NHRA class that rewards efforts of people who are involved with a normally-aspirated class (like NHRA's "Competition Eliminator,", because the head was DESIGNED for that size engine. The ports and valves work great on that size motor, yielding terrific horsepower-per-cubic inch numbers... it will beat the crap out of just about any other (2-valve) motor it goes against PER CUBIC INCH... That has been my experience, at least. Ramcharger Pete McNicoll built a '40 Willys coupe with a 170 and took it to the NHRA Nationals at Indy, in 1961, (I was there!) and made all the other 6-cylinder race cars look like they were backing up! I think it may have run 14-flat at 100-mph... fifty-two years ago.
The 170 has a short stroke and will easily reach RPM-levels that other, longer-stroked slant sixes can only dream about.
That is what it does, well... and, it does that VERY well!!!
The secret, is that the cylinder-head was one that the design-parameters were formulated for that original-displacement slant six, which was a 170... period.... that was the only slant six available.
Number Two: The following year (1961) saw Ma Mopar searching about for a larger-displacement six that would be capable of carrying a 3.600-pound B-Body Cornet wagon to the grocery store or down the highway, keeping up with traffic, all-the-while.
The 170 was just not up to the task, with its basic, one-barrel "economy" version, engine. The necessary torque was just not there; it was asking too much. The Hyper-Pak was arguably too radical for the street...
Narrow bore-center specs (the same for ALL slant sixes,) dictated that there was no room for much bigger pistons, and since more torque was what was needed, Ma just added a 1-inch stroker crank, which raised the displacement to 225, a nearly 33% increase.
That did the trick, and provided the need torque with the same-size pistons, head, and no changes were necessary to the rest of the engine except for the deck-height, rods and piston mods to accommodate the longer stroke.
THE CYLINDER HEAD WAS UN-TOUCHED!!!
Now, we had a new, larger, engine that had gone from a a free-breathing (albeit small,) high-revving, "racy" powerplant, to a strangulated, asthmatic, "high-torque" stump-puller, due to the decidedly small and ineffective-for-performance, ports and valves... a situation that was to plague the slant six in its 225-displacement-size for the rest of its life...
People who have attempted to get good numbers out of normally-aspirated slant six race motors that are relatively large-displacement, have faced an uphill battle and have been usually-disappointed in the results, generating flow-bench numbers from mediocre, to downright poor, due to the head's inability to allow flow in the meaningful range, even with the usual big valves and radical porting. The raw material is just not there.
A 2+hp/cu.in., normally-aspirated 225 motor is practically an impossibility.
Fabo's 305Moparkid has a '68 Dart with a 225 in it that has been treated to MOST of the usual hop-up) tracks, higher compression, more carburetion, headers, a ported head, bigger valves, a more radical cam, a deep rear-axle ratio, a fiberglass hood, suspension mods, a better ignition system, drag slicks, and a transmission re-work.
He knows what he is doing...
Not to belittle his efforts, because I am sure I could do no better, but his car has yet (to my knowledge.... correct me if I am wrong, Ed,) to run quicker than 14-flat, nor 100 mph in the quarter-mile.
You can do that with a well-tuned STOCK 340, I believe (on the same slicks, like he used) slicks and with a gear.) Much more cheaply.
FABO member Tom Wolfe (Shaker223,), a few years ago went junk-yard hunting and found a '78 GN Buick turbo, bought a used, aftermarket 4-bbl slant-six intake manifold and without taking the head off his otherwise stock, 1970 225 Dart Swinger with 105,000-miles on it, added a Holley 4-bbl carb, the Buick Turbo, and with NO OTHER modifications, ran 12.95 and 104mph.
What he did was, make an end-run around that bad-breathing cylinder head.
Here's the video:[ame="http://www.youtube.com/watch?v=pPe_vHwZsF4"]Slant Six Turbo 1970 Dodge Dart 1/4 Mile pass - YouTube[/ame]
He has since, with a modified engine, run a best of 11-flat and 120+mph, into a 15-mph headwind.
You pays your money and you takes your choice...
But the real reason I wrote all this was to try to illustrate why a turbo-170 is not good bang for your buck (MY OPINION
ONLY.)
The 225 is SO MUCH larger (displacement) than the 170, (virtually 33-percent,) it would seem that a very-mildly modified 225 would put out as much power as a 7-pound boosted 170... at a lot less cost.
If that's true (and, I believe it is,) I think it might be smarter to just hang onto that nice A-Body and wait, however-long it takes, to get a 225 short-block, sell the 170, and go with a mildly-turbocharged version of that 225.
The performance difference would be dramatic!!!
A turbo-170. boosted to the amount of power that even a mildly-modified normally-aspirated 335 could deliver would probably be the more-expensive of the too...
To reiterate, I am far from an expert, and probably not qualified to give out advice like this, but, maybe take it with a POUND, rather than a grain of salt.... LOL!
On a different tack...
Boost referencing means that the regulator is subjected to manifold-pressure and will add to the fuel pressure, that exact amount as the boost rises, so that the needle and seat never see a pressure-differential different from the status quo, at an idle. (no boost.) Regulators are readily-available to provide that scenario. That would give six pounds of fuel pressure at an idle (no boost) and 16 pounds at 10 pounds of boost. Otherwise, the fuel gets forced back into the supply-line by boost pressure...
Hope that helps!:blob:
This ia just MY opinion... your mileage may vary... and, probably will.... please forgive my arrogance. My 2-cents...