Ah, the ol’ 270 Jimmy: really great engine, for its day, and THE go-to hot rod engine, before the venerable SBC!
I’ve mentioned this before but many years ago I started to build a Jimmy. The 302 was the “hot setup” but expensive and few to be found whereas the 270’s were plentiful and cheap, so 270 it was. I was able to purchase a complete short block and in these days of thin wall casings it’s hard to believe that those engines could be bored almost 1/4” actually 7/32” which turned it into a 302! After getting pop up pistons( remember those Carl?) and the crank assembly balanced, I ran out of money and traded the engine and car, 39 Chevy coupe, for, of all things, a hot rodded 37 Buick which could clean an Olds 88 up to 90MPH or so. How did we survive those days of street racing?
Bob
889076
Plymouth,Mi.
I do believe that Frank has given me the insight as to why a previous owner stuck an XJ6 emblem on this car: to quiet the V12 mafia. Maybe I will put V12 emblems back on the car and stand back and wait while random people tell me in anguished tones that this car has been ruined…no longer a sophisticated cat, that its just a pub trawler now. The nearest Jaguar dealer is more than 300 miles away. The nearest independent Jaguar specialist is also more than 300 miles away. All the local older (30+ years) XJ6/12 and XJS that I have seen come up for sale in recent years all had a SBC lump - and it seems that even on eBay a high percentage of older XJ6/12 and XJS are lumped.
Its okay really, I’ll just go to street rod and muscle car shows where automotive debauchery is appreciated and even encouraged. Since the XJ of any series is so seldom seen at car shows, I’m sure that many people will peer under my hood and not even recognize that this cat has been engine swapped.
I’ve purchased a couple of emblems that I will be attaching to a new set of valve covers so that I can start hood up conversations with a made up story about my car being equipped with special export market options
Meanwhile if anyone knows the whereabouts of V12 engine # 7P 27891 - I have the matching car!
Wiggles, oh I am going to have fun with it - I like to have fun with old cars! Sometimes that means there will be critics, and I also want to poke their funny bone.
I once owned a 1963 Studebaker Avanti R2 4 speed that even though most people had never seen one in person it seemed to draw out the latent concours judge in spectators. At one show I was nearby and noticed a man giving it a thorough going over. So I walked up acting like another spectator. I casually asked him what he thought of this car. He replied that it was a nice car but not very original (it was actually a highly original example). Eagerly I asked for more info on where this car went wrong. He first picked on the engine for the chrome valve covers, valley pan, and air cleaner (which were actually factory standard to the Avanti). “Oh” I said, “tell me what else” - and he pointed to the Paxton centrifugal supercharger and said “that thing right there.” So then I led him over to a laminated copy of the original window sticker that I had on display (I had all the original paperwork from the dealer purchase, and I thought the laminated display copy would be fun for spectators). I went to the line showing the supercharger as a $210 option in 1963 - then I asked him if he thought the original buyer paid too much! He paused for a moment then gave a hearty laugh and looked at me and said “I learned something today.” We shook hands and he loosened up and I encouraged him not to get uptight about the cars because he would never be able to “save” them all from their owner’s tastes and decisions.
Indeed, I do. A more “sophisticated term” was "domed?
A way to raise the compression.
Way back when, circa 51, there was a Chevv coue in town. Either 38 or 39. Jimmy under the hoods. Which? not known. but it would "haul … ".
An unc was a great DIY guy,. Taught me a lot in “tool disclipline and hard work”. One of his “income streams” was hauling. A circa 41 Chev tractor and a flat bed semi trailer. Moved tractors and the like for farmers or hay. He got wind of the 270. Out with the Stove bolt ands in with the Jimmy.
Circa 1979. A circa 68 Toyota FJ40 came aboard. It’s OHV 6, a virtual copy of an 261 or so 261 Chev truck engine. But, not quite. Well, I rebuilt twice. Don’t ask!!
Two engines became one. Flat top pistons in lieu the dished ones. Closed chamber head in lie of the open chamber head.
How much more CR, I don’t know. Bu, 87 octane no longer OK. Much, much snappier. Other mods, as well…
I have lumped many vehicles over the years. usually because I felt the ‘different’ drive train was an improvement but sometimes because it is what I or the owner had available. with my xjs, I would not do that because I feel the v-12 makes the car what it is. that being said, I can see why others would go this route. the sbc is probably the most affordable and easiest to find motor, it is easy to work on where most gear heads would be lost working on the v-12 and parts are available at any parts store along with performance parts being much cheaper. I usually go in the other direction because I want something different or custom. at any car show I attend, I see rare or unusual cars seldom seen, and find another 350 chevy in there. being lumped really doesn’t bother me, lumped with another sbc does only because its not rare, its common.
Definitely some Jimmy fans here. Now that I think about I got to see the might of this engine when I was at the Bonneville Salt Flats for Speed Week in 2006 (I was part of the crew of an effort to get a Studebaker powered Avanti past 210mph which ended when the car’s original crankshaft split in half at 185 mph).
There was another legendary land speed racer there, Joe Fontana, who had been coming to Bonneville for 50 years. For Joe there was only one engine that mattered - the Jimmy! After decades of chasing setting a record in a class that kept on moving higher he finally made the record books in a big way: his flying mile average speed was 256mph in his streamliner. I believe his exit speed at the final mile marker was ~ 265 mph! All that with probably the most potent Jimmy ever assembled. I was astonished to see him pull it off since I didn’t think it was a wise idea to have an 82 year old man driving a streamliner in the first place. What if he crashes and dies I asked - and the answer back was that this was his dream and that he had passed all the driver requirements. At the 200mph Club Record Holders celebration dinner Joe absolutely made the funniest impromptu speech about his long path to success.
They have race classes for just about everything, there are sub 100mph records in esoteric classes waiting for you to challenge. Lots of antique and oodball combos to satisfy the dare to be different racers. Most racers are hard core amateurs - but from time to time a gigabucks effort will show up: https://newatlas.com/honda-volkswagen-2016-records/45552/ - how about 277mph with just 660cc’s, or a 205mph Beetle!
You absolutely must go - it is not possible for video to capture what it is like to witness a car going 450mph:
His parachute came off, I think he was still going too fast when he opened it - he went for a miles long bumpy ride on non-dredged salt flats. I think it took them an hour round trip to find him and bring the car back. Driver was fine, just thirsty after a wild ride and waiting for his crew.
yes, the rotary in a chevy is interesting, the small block in the ferarri is a step backwards. I like seeing how they adapt and modify, especially the parts they made from scratch. the stove bolts and big jimmy sixes were before my time but currently have a built 292 chevy I put in my van. I am constantly asked ‘why didn’t you just put a 350 in there?’ my answer is ‘everyone swaps in 350’s, nobody has done this!’
tons of torque off idle where the sbc needs tacked up to get the same power. not as much a problem in a light car but when weight goes up, it becomes a bigger factor. my first 292 was in a c40, a mid size truck. it would out pull 350’s in similar trucks easily.
One of my dad’s friends had an older Chevy 40 series flatbed 6 cylinder. Transmission had a compound low for starting out going uphill or with a heavy load, normal driving started out in second gear. It had a big heavy flywheel to help avoid stalling out if the clutch was released too quickly, big heavy flywheels make an engine feel torquey just off idle. Its true that nothing would stop it, very slow acceleration, just barely made 55mph on the highway - it sounded very unhappy when pushed to higher rpms. My brother and I called it the emphysema special - because it ran out of breath way before our eager right foot was ready!
I watched a rerun of “Pawn Stars” last night. In for sale.
A 1940 Buick Special four door. Claimed to be a “Torpedo style”. Wrong, a “notch back”. Claimed to be Fidel Castro’s car in his Mexico days before going to Cuba as a revolutionist. No support.
Long shining black Four r door. Skirted rear fenders. Yellow “fog” lights on the front bumper. Oddish window mounted “swamp cooler”.
Alas no classic Blue Straight 8, “Blue Flame” OHV engine.
The nice looking red SBC just lost in the bay. And a “Muatang” shifter on the floor. No noisy Buick three on the tree.
Other sad things to a car. Although not a top of the line for 40 Buicks.
OTH, on wheels ,running and driving… That can’t be bad.
Similar to my ‘rent’s ‘35 Auburn Speedster: over the years they owned it (1950-1988), and I stewarded it, MANY folks would approach them/us, and declare, “My dad/brother/uncle/5th cousin’s third wife’s ex had one JUST like this!”
We’d all knowingly nod to one another, and say, “1,290.” The folks wouldnt have a clue…
Yup, more than a few Auburns ever made. But, as you say few of them were speedsters.
Circa 1950, there was a small ;“junk yard” in El Paso’s lower valley. How the pleasant husband and wife made a living there was beyond me, even then. Two untouchables in their yard. One a complete but faded Auburn coupe. It’s fate unknown to me. Today, it would be gobbled up for big bucks.
The other a "sprint car’. Cobbled together, with a biggish truck engine of an unrecognized specie!!1 It failed to even look like a racer??? “Modified Jalopy Racer”, perhaps, at best.
You won’t get that from me. Yours runs, mine doesn’t.
The term “lumping” came from the British, at least I never heard it until the internet and I made contact with Brits. It was known with XK120s that tended to overheat, and with XJ6s it started in the 70s when there was poor quality control at the engine plant, and they couldn’t take a lot of overheating. Owners would let the coolant level drop, they’d overheat, and a lot of cars dropped valve seats, often when they were off warranty and in the hands of somebody who didn’t want to pay for a proper rebuild. Chevys were an order of magnitude cheaper in the US, perhaps elsewhere as well.
If it really bothers you, you could find this car and swap.
