And that's my point. Most people still don't.
Might not see the cars in the pull a part anymore, but doesnt mean they aren't out there for peanuts from the ls-crazy crowd who doesn't know they've got a boost able motor already in the car.
Intercooled GN's or EFI 5L 5 spd Notchback Mustang's, which were faster bone stock?
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Might not see the cars in the pull a part anymore, but doesnt mean they aren't out there for peanuts from the ls-crazy crowd who doesn't know they've got a boost able motor already in the car.
As long as the tune is on point the 109 motor can take a lot. Usually when you see a windowed block or the car joined the driven over the crank club something bad tune wise happened.
I grew up with factory stock cars that were older (and many times faster) than both the 5.0 Foxes and all of the IROC series cars. I also worked on the 80's cars daily. I can tell you straight out, the stock GNs were the fastest of the three. The statements that the GN's "were frequiently out of tune" are patently incorrect. The OEM injection on them was no worse than the TPI on the IROC or the EFI on the GTs.
That being said, my DD was a '77 olds Omega, 305 two barrel, single exhaust, three on the tree manual transmission. I tossed on a cast iron GM intake and a Quadrajet, swapped the three on the tree for a four speed Saginaw on the floor and it would run dead even with every stock 84-86 GT around. It was a low 14 second car on its BEST run ever...
Tommy
That being said, my DD was a '77 olds Omega, 305 two barrel, single exhaust, three on the tree manual transmission. I tossed on a cast iron GM intake and a Quadrajet, swapped the three on the tree for a four speed Saginaw on the floor and it would run dead even with every stock 84-86 GT around. It was a low 14 second car on its BEST run ever...
Tommy
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Oh, Tommy... do I have bad news for you.
But, I don't have the capacity or interest to write a book on how incredibly convoluted and temperamental the Buick's SFI was compared to a batch fired TPI or Ford's EEC EFI.
The reason buicks were "out of tune" was Bubba cutting the wastegate with a hacksaw, trial and error swapping injectors from other vehicles, and not having computers showing exactly what was going on in the process.
In stock form, which is what we're talking about, they weren't out of tune from the factory leading to the drivability and usability issues implied.
Ditto.
The fact that almost every factory GN EFI related sensor or module has a more modern replacement is evidence alone.
MAF translators to run LT1 MAFS, what means OEM MAFS were crapping out in 1995
Type II or LS ignition module driver and coil conversion kits
The hoard of Casper's Electronics harnesses (fuel pump hotwire, alternator tickle power harnesses, fan parts, ect, ect.
They were probably in tune from 1987-1990 but the first time a vacuum line got knocked off at the dealer when it got brought in for a valve cover gasket change, someone tossed 87 in and kissed a piston with some detonation, plugged a fuel filter, they went out of tune.
People didn't have hand held OBD scanners or the widespread knowledge to diagnose and fix EFI problems.
TPI 4.3 and SBC 80's/90's trucks will run on 6 year old lawnmower gas down on 3 cylinders. They at least still had distributors and were the same SBC's as 1968 but with a slightly different carburetor (TBI). The GN with its computer individual coil ignition, MAF's, boost control solenoids, boost reference fuel pressure regulators is a magnitude more at risk for being out of tune.
Yeah, chasing issues on these old EFI sucked. A lot of trial, error and throwing parts at them. They just didn't throw codes till the car was basically undriveable.
When everything is working, they are great. Once you start chasing issues it's a huge pain in the *ss. Parts store parts don't work, even if you can find them. Luckily we have people like Bob Bailey and other mad scientists who have come up with fixes for some of the problems. With tools like the Scanmaster and powerlogger it is much easier to track down issues but sometimes you still get some really odd sh*t.
I am going over to an aftermarket ecu (Holley HP) on my car. All new wiring, No more MAF, common LS style coils, wide band, safeties that can be setup to help save the motor if things go sideways. Upgraded stock SFI stuff can take you very fast but modern EFI is MUCH nicer.
Hell, stock for stock, one tank of regular or bad gas and the Turbo Buicks became a stone.... if they didn't blow up and get a carb'd Chebby swap as a result. TPIs and 5.0Ls didn't suffer the same fate.
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