engine family

[dw230]

From the front page of this website:

The agenda for the May meet is:
May 13, Friday, Inspection noon to 4:00pm
4pm Rookie Orientation – meet at Registration Trailer
5pm Course Walk

May 14, Saturday, Inspection 8:00am to 4:00pm
   At the Start Line:
      7:00am  Patrol Meeting
      7:15am  Driver's Meeting
      7:30am  Start Running

May 15, Sunday, Inspection 7:00am to 10:00am
   At the Start Line:
      7:00am  Patrol Meeting
      7:15am  Driver's Meeting
      7:30am  Start Running

DW

[zenndog]

Test case

Chevy 235 or 261, the inline motors available as standard options in 1958 Chevy trucks, according to wikipedia.

http://en.wikipedia.org/wiki/Chevrolet_Straight-6_engine

GM atlas engine, also an inline 6 motor.

http://en.wikipedia.org/wiki/GM_Atlas_engine

http://www.scta-bni.org/Bonneville/SpeedWeek_10/photos/photos_15/Set_2/CIMG4784.JPG

Same bolt pattern?

Same bellhousing?

Correct be if I am wrong but I assume this truck is running an atlas engine based on the cubic inches marked on the hood. But isn't that a stretch for E/PP, or do I not understand the rules.

Zenon

[Dreamweaver]

254 ci?

Ive never seen under the hood of that blue truck but it could have a bored/stroked/destroked inline 6 or a bored/stroked/destroked V8.

[fastman614]

A 254 V8 was an easy engine to build if you had a 262 Chevy Monza/Nova V8 from 1975 to 1976.... you took out the 3.1 inch stroke crank and put in a 3.0 inch stroke crank.... and the truck WAS legal with any SBC motor.... as it was the same engine family as a 265 or 283 V8.... there are also A LOT of 2.9 inch stroke SBC cranks out there.... one of those in a 265 block or in a lare model 305 block, you get a displacement around that ..... it could also be a LATE model 250 CID Chev inline 6 with a .030" overbore.....

I figure... if that truck had a STOCK inline 6..... it would be running in XO class.... wouldn't it?

[zenndog]

    I am new to this and it all makes my head spin. Maybe it is a destroked V8. I can not find any info on the truck. It must be some simple explanation like that. I just ass-umed that it was an Atlas engine based on a Google search of "254". Zenon

[4-barrel Mike]

No questions about the El Mirage record holder's engine family.   



Mike

[zenndog]

Fastman-I get what you are saying, it must be a v8.


So inline engines always run in XO?

[Stan Back]

No -- only some vintage inline engines.

See Rule Book.

[RichFox]

If it was a 235-261 based engine it would have to run XO. V8 should be good for PP. Atlas I don't know.

[zenndog]

No questions about the El Mirage record holder's engine family.   



Mike

There are no questions about the Bonneville record holder either. It is running a destroked V8. This question came about just due to me trying to understand the rules and only racing on the internet and in the rulebook.

If I understand correctly, an engine from the Atlas family could not run in a 50's Production Pickup, and an inline 6 from those models would run in XO. Let me push this one step further though, If someone wanted to run an inline 6 in a 60's, 70's, or 80's pickup for ?/PP, they could and it would be in the engine classes denoted by A,B,C,etc....because the cutoff for XO is 1959?

[RichFox]

Yes. If you had a '57 Chevy pickup and installed a later 7 main bearing (194-215-230-250-292) Chevy six you would run in the engine class your cubic inches fit. XO and XXO would only be for 216-235-261 type of engines and I have seen the earlier  ('49-'55 first gen) get buy with 270-302 GMC motors and you could always badge the thing as a GMC I guess.

[zenndog]

Thanks for the education. Seems that it is somewhat a moot point since obviously guys are running smaller bore V8's in PP. I will say it is interesting that the record holders at Bonneville and El Mirage are a 50's and 60's pick up since the class of ?/PP is so wide open in terms of the model years available. Those are great bodies to look at but seem to be low on the aero factor.

Mike- Is #981 your truck? Thanks for the pic and the input either way.

Zenon

[4-barrel Mike]

Not mine.  I like it, though, because I have a yellow 1960 F100 panel 

Mike

[fastman614]

No questions about the El Mirage record holder's engine family.   



Mike

There are no questions about the Bonneville record holder either. It is running a destroked V8. This question came about just due to me trying to understand the rules and only racing on the internet and in the rulebook.

If I understand correctly, an engine from the Atlas family could not run in a 50's Production Pickup, and an inline 6 from those models would run in XO. Let me push this one step further though, If someone wanted to run an inline 6 in a 60's, 70's, or 80's pickup for ?/PP, they could and it would be in the engine classes denoted by A,B,C,etc....because the cutoff for XO is 1959?

Of course, they made the old Ford Y Block stock with displacements of 239 and 256 cubic inches.... both were L

[fastman614]

OOPS!.... my sausage sized fingers hit the wrong button.... both were LEGAL sized E Class motors..... but ...... I sorta think a kicka** smallblock of under 260 C.I.D. could pack a few miles per hour on to the record.