What would a mid 80s sbc nascar engine consist of?

[PackardV8]

just open up the two metal doors that formed the rear of the dyno cells, turn on the fans, and and enjoy unfiltered that beautiful, magical song that a Cup motor sings when it comes up on the sweet part of the cam around 6800 RPM and starts "doing business".

For true. I was at a Vintage road course race and there was a beautiful '68 Boss 302" Parnelli Jones clone. The Vintage guys don't really do engine tech, but this guy never raised the hood in the pits. He couldn't hide the fact when he was on the front straight, he pulled the legal SBF cars like they were roped to a post and that sound was unmistakable; once heard, never forgotten.

While wandering off-topic, at that same Vintage race was a '69/'70 big block Corvette with the side pipe headers. I first heard that sound at Le Mans in 1969 and it too is unique and immediately recognizable.

[F-BIRD'88]

Funny that the oil trough under the flat tappet cam never caught on for street strip. Might even help a roller cam lifter live longer.

[Racer#01]

In 1985 Chevy produced a siamese bore 400 small bock. Called a BOWTIE BLOCK. And 18 degree aluminum heads. Gm manufactures ran the same heads but had the manufacturer cast on them.. I have owned pontiac and Buick versions. I have personally never seen chevy versions. The DEI engine I ran in my super late model in 2002 had a Crower rotating assembly. 4.125 bore, 3.33 stroke with honda 1.8" size rod journals. the crankshaft weighed 36 lbs. My engine came with the Pontiac head casting number but was blank where "Pontiac" should have been. With 2.12/1.65 valves. They weren't legal so I used a set of highly ported 18 degree cast iron BOWTIE heads with 2.08/1.6 valves.
The engone put out 850hp with cast heads. My boss picked up 6 different DEI engines at auction when the SB2.2 came out. They were all raced and needed freshened. . All of them had different components inside. Some had 3" stroke but none were over 3.33 stroke mine was a 360 CID cold and 357 CID hot acotding to the many tips through tach inspection. So there is no exact formula for a CUP engine from the 1980s... but from what I gathered it was learned in the 1970s you could build a 357 CID using a forged large journal 327 crankshaft in a .030 over bore 400 block.. that has is where it realy started

[rebelyell]

..........So there is no exact formula for a CUP engine from the 1980s... but from what I gathered it was learned in the 1970s you could build a 357 CID using a forged large journal 327 crankshaft in a .030 over bore 400 block.. that has is where it realy started

^^^THIS^^^

[Tom68]

Old thread. We bought 20 GM and 5 Ford Nascar winston Cup engines in 1986.

I might still have a cam box with the specs in it, GM's had Aluminium bowtie heads.

[GARY C]

I rarely watch it now and if a Toyota ever wins the great AMERICAN race I will not watch that race again either.

Why? Toyota is a public company traded in the USA, and employs many Americans to make its cars. I'm sure the NASCAR team has American drivers, pit crew, engineers, and the motors are built there too. I don't see the problem.

If I am not mistaken when Toyota entered NASCAR it was the only body style in the field produced in the US, the others were Canadian and Mexico...

[rebelyell]

I've been out of that loop for quite some time, but it seems about the only things Cup bodies had in common with their production counterparts were floor pans and roof skins.

[GARY C]

I've been out of that loop for quite some time, but it seems about the only things Cup bodies had in common with their production counterparts were floor pans and roof skins.

I doubt they use many actual factory parts but the mnf's got more say over the car designs a few years back.
Photo of the 2022 Mustang, 4 wheel independent suspension, 5 speed trans axle drive train, aluminum wheels. Looks pretty much like a mustang.
https://s1.cdn.autoevolution.com/images ... ter_23.jpg

Camry, Mustang and Camaro side by side photo.
https://www.americanracingnetwork.com/w ... txGen3.jpg

[Tom68]

I've been out of that loop for quite some time, but it seems about the only things Cup bodies had in common with their production counterparts were floor pans and roof skins.

A little more than that in '86.

Floorpans were all the same, a 60's Ford pressing.

Cup Cars '86.JPG

[Tom68]

87

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[Tom68]

Calder Shop 1987.jpg

[bob460]

87

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What power did they make back then and at what rpm's.

[Tom68]

87

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What power did they make back then and at what rpm's.

I think we were low to mid 500's and Bob Rahilly brought over a high 500's, high 7's mid 8000 RPM's, I took a ride with Richard Petty on launch day (sitting on the floor, hanging onto the door bars ) I saw high 7's (memory of 8200, but could be wrong) at the end of the straight (we had a 3.9 gear rule wih the tall cross plys) I also saw him tap the brake to make sure he had a pedal before lifting off.

If i've got that wrong, we were 580 and Rahilly was 620. Memories.....so many to mix up.

Launch day Thunderdome Melbourne.

Calder Launch.jpg

[PackardV8]

87

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What power did they make back then and at what rpm's.

Today, when sometimes 500 miles is run with no engine failures, we forget how fragile they were back in '80s. There was an inverse relationship between power and finishing the race. Back before purpose-designed race engines and the gear rule, wasn't unusual for half the field to drop out with engine failures.

[juuhanaa]

What power did they make back then and at what rpm's.

Today, when sometimes 500 miles is run with no engine failures, we forget how fragile they were back in '80s. There was an inverse relationship between power and finishing the race. Back before purpose-designed race engines and the gear rule, wasn't unusual for half the field to drop out with engine failures.

Perfect time to spread good news about Folkracing, i know it doesnt look like nascar

Captain slow explains the rules in part 6:00 --->

https://youtu.be/2bmqdnx5R1U



-juhana