Why I Converted My 1979 Volvo 245 From Fuel Injection To Carburetion – Jalopnik

That’s my brick. It’s a pale purple. Officially, Volvo calls it Cimarron Red, however why did not they simply name it Brick?  Anyway, the hue is not — or at the very least hasn’t been — my focus since I acquired the automotive from Eureka, California, a yr and a half in the past. Yes, I additionally hunted Volvo 145s, however most I spied wanted method an excessive amount of TLC — like this one. There was only one drawback with my brick: The prior proprietor ditched the inventory gas injection, generally known as Bosch Okay-Jetronic, which got here on U.S.- and Canadian-bound variations of the B21F engine within the late Nineteen Seventies. Instead, he switched to a throttle-body gas injection, by the use of the Holley Sniper EFI 1100. The automotive by no means ran proper with the Holley, and my mechanic good friend, Ryan, made two damning factors about its shortcomings.

First, it lacks an Internal Air Temperature sensor (IAT). For about the identical $1,100, Summit Racing sells a throttle physique equipment with an IAT, nevertheless it did not come on the Holley. Ryan stated the explanation that issues is since you desire a reside studying of air density throughout combustion. He defined that Holley’s downstream sensing (within the exhaust) was all the time back-calibrating the ratio of gas and air. The system I had additionally solely allowed code tweaks by way of an SD card. 

Sure, you may buy a setup to live-calibrate the Holley with a laptop computer, however with out an IAT, I’d nonetheless have zero assure of clean operation sooner or later. So, I used to be left with two selections: to discover a salvaged Okay-Jetronic, or go even farther again in time and revert to a carburetor. I went the latter route, and the choice got here right down to me being an affordable automotive journalist. Well, largely.

Trust me, I thought-about discovering a viable Okay-Jetronic mechanical fuel-injection answer. Okay-Jet in numerous varieties dates all the way in which to the late Sixties, and was utilized by many different carmakers, together with Volkswagen and Mercedes-Benz. I’m not telling you precisely what I paid for my automotive, however I will inform you, as I have already got, that it wasn’t a fortune — nor do I’ve one to spend on making a not-mint Volvo right into a parts-perfect museum piece.

Just to make this clear, Okay-Jet consists of a gas pump, accumulator, gas filter, airflow sensor, warm-up regulator, gas distributor, injectors, chilly begin injector, Thermotime change, and auxiliary air machine. I’d want to accumulate all of that. Then I’d want the proper manifold, too, since that was lengthy gone from my automotive. I’d additionally should fetch the right wiring harness for $320 from an outfit referred to as, fittingly, Prancing Moose. I’d already sourced a harness from there for the overdrive my buddy Joe put in my automotive. I held the flashlights and whinged together with Joe, who did all of the precise work and troubleshooting.

Anyway, even tabulating prices with a boring pencil and a greasy serviette, I used to be positive going the Okay-Jet path would price me far north of $1,000. Yep, a junkyard Okay-Jet may work. Or I is likely to be rebuilding each single half. Rebuild kits exist from the likes of Volvo components provider IPD and Australia’s Okay-Jet Specialists. Still, meeting can be delicate and fussy, and I’d want instruments I haven’t got, like pressure-testing tools required to get the calibration good.

Going the carb route wasn’t as loopy because it sounds. My similar 240, offered in different markets, bought a B21A engine with a Stromberg carburetor. And, really, the final carbureted automotive offered new in America was available on the market in 1994, which simply reveals you that early gas injection hardly satisfied each carmaker that it was the right fueling answer. As for which carb path to take, I might have spent $892.14 for that unique B21A Stromberg. But why do this when Classic Car Performance sells an entire Weber 32/36 DGEV conversion equipment for $569.99? And as a result of the Holley conversion meant I already had a superbly good Pierce manifold on the 245, I knocked off one other hundred bucks by not needing that half.

As I noticed it, the good thing about deciding to make use of the Weber was comparatively easy tuning and mechanical simplicity. As a reminder, a carburetor has jets which are basically screws with holes in them exactly sized to permit the correct amount of gas to get sucked in as air passes by means of the barrel (or barrels), managed by a drop in strain, and the gas-and-air combination will get ignited throughout the engine.

Now, swapping over to the Weber wasn’t an enormous deal — particularly in comparison with Okay-Jet — as a result of the inventory gas injection was already gone. All Joe and I needed to do was ditch the high-pressure gas pump and go to a a lot lower-pressure mannequin (included within the equipment), take away the Holley system, and substitute the Weber on the manifold earlier than hooking up the throttle cable and choke.

Well, form of. There had been some problems. I needed a guide choke for higher cold-start reliability. There are Weber 32/36 DGEVs with automated chokes, however these have a status for not working reliably. Still, the inventory choke cable needed to be fished by means of the firewall and mounted beneath the sprint, and that and the throttle cable had been each insanely lengthy, requiring mods which are nonetheless ongoing. We’re not executed but. Partly as a result of the carburetor nonetheless must be fine-tuned. The Weber for my automotive in all probability wants jetting — or at the very least swapping the idle jet — since idle generally is a tad tough. And we’re not but positive about the principle jet, both. Timing? We’re fiddling.

However, the 245 runs a lot better already. At idle, it does not sound prefer it’s alternating between drowning and coughing, and at half throttle it desires to speed up slightly than sputter. Plus, now you can stand behind my 47-year-old Volvo when it is operating with out fearing you will cross out from a spew of unburnt gasoline. 

I nonetheless have homework to do to get the Weber working completely. Fortunately, there are various inputs to fiddle with — and these are all simply screws, not traces of code, which feels sincere. I purchased a really analog brick with a guide gearbox and never even a working radio to expertise automotive atavism. It’s a return to the rudiments of driving. My spouse and I additionally simply purchased a used Hyundai Ioniq 5, as a result of we’re not resistant to the melting planet. The Volvo is and can be an event automotive, pushed to clear my head. And additionally, whereas it is mine, I need to remind the world that wagons are cool, and we are going to miss them sorely after they’re gone.