GM 250's on 25% nitro!

bmbm40

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Pretty awesome! Never occurred to me countries like Brazil are hopping up old straight six motors in this case GM. Kind of like an alternate universe.
I wonder what they are doing with the Ford 200/250.
 

Pete62SOHC

Well-known member
They're big on the Ford 6's as well as slant 6's, too, from what I understand. GM never offered a V-8 in Brazilian-produced GM products, so the 250 has a long, rich history of modifications and racing in Brazil. There's even companies in South America that produce billet blocks, exotic cylinder heads, etc., for the GM 250.

Ford offered the 302 and Chrysler offered the 318 in Brazilian products, but from what i understand, I-6 production still heavily outweighed the V-8 option in both product lines.

What's extra impressive (to me, anyway) is that the cars featured in the video still utilize OEM production cast iron engine block and cylinder head castings. Awesome stuff!!
 

Pete62SOHC

Well-known member
Not sure... You could try posting a forum link in the comments on the YouTube videos of these cars. There's TONS of videos of Brazilian I-6 stuff in action. I couldn't stop and ended spending all last night watching them. Amazing stuff going on there.
 

rocklord

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Brazil mandates use of ethanol as a vehicle fuel; they grow their own sugar cane that is converted to ethanol decreasing dependence on oil imports

Ethanol is lower in energy content, but has a higher octane rating (100+) making it a cheap racing fuel.

I'm sure the Brazilians are taking advantage of the higher octane in their fuel.
 

bubba22349

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:shock: :wow: looks like lots of fun! Back in the late 1960's and early 70's used to really enjoy seeing the Top Fuel and Funny cars run. Even got to see a few top fuel motors apart at Keth Black's Racing Engines (my friend worked there) on the 426 Hemi's. And I also was at a small shop buying some parts for engine build of private Top Fuel racer "Starlight dragster" he ran a Ford 427 SOHC, and at Ed Pink's shop who also built the 427 Ford SOHC for Ford funny car racers like Gas Ronda.

It Would be very interesting to know what parts they use in Brazil to make their six'es run like that and stay togeather, maybe someone from over their will share some info with us. In the Below link is some history & info on Nitro fuel and some other fuels they use to mix with it. :nod:

Nitro
https://www.hotrod.com/articles/hrdp-13 ... ne-anyway/

Top Fuel Facts
http://www.sccoia.org/articles/top-fuel ... ast-facts/
 

Pete62SOHC

Well-known member
I worked for Loper's Performance for about 10 years, and as you may know, John Loper raced Fuel back in the '70's and '80's. One day an old local Fuel racer who was a friend of his came into the shop with a KB Fuel Hemi crankshaft to have it checked for cracks. John looked at me and said, "Young man, grab that crankshaft. I'm gonna show you how to check a Fuel crank for cracks."

He and I took the crank back to the machine shop, where he instructed me to sit the crankshaft on the ground, standing upright on the flywheel flange. As I held the crankshaft steady, he took a brass hammer out of the toolbox and proceeded to hit the crankshaft with the hammer on the snout with one hard, sharp blow. He then showed me all the areas on the counterweights where oil had sprayed out from small cracks in the fillet radii of the rod journals.

We took the crank back up front where he informed his friend that the crank had about 2 dozen passes left on it before it let go. He explained how you could tell by the amount and distance of the oil spray just how deep the cracks were, and how those identifiers could be used to estimate the remaining life in the crankshaft. He then went on to teach me how he used to tune his Fuel engines, which was to mic the thickness of the upper rod bearing shells after each run. I learned a lot from John Loper.
 
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