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healeyboz
02-12-2007, 07:03 PM
I figured out the rocker arm assembly problem thanks to Hap and a few other guys. The guy that I originally got the head from is happy to get it back and is sending me another. He said that this head has been slightly milled and was intended to be a back up for his son's autocross car. I have an email to him asking if there is anything else done to the head (performance wise). Is autocross a class in racing? Obviously I will have to see the head and take measurements to see what has been done, however, are there certain specs that I should expect when it arrives?

swift6
02-12-2007, 08:55 PM
Autocross is a coned course timed event, usually in a parking lot, where you race the clock. Also known as 'Solo 2' in the SCCA. Fastest time of the day wins. Used to be referred to mostly as Gymkhana's.

aeronca65t
02-12-2007, 09:40 PM
Yep, as Shawn said, it's racing around cones, one at a time to see who can do it fastest.

You can get info on your local autocross (or "auto-x") events here:

https://www.sirscca.org/autocross.htm

healeyboz
02-12-2007, 10:05 PM
Thank you. I will check it out!

no_cones_ever
02-12-2007, 11:08 PM
check it out...this is autox for sure rotary bugeye (https://www.youtube.com/watch?v=jtOLwF2J9b8)

healeyboz
02-12-2007, 11:09 PM
This is the email that I got from the head builder.

>The head I sent has been prepared for SCCA autocross regulations in D
>-Prepared. This is similar to the requirements for F_Production in road
>racing. The valves are the largest allowed. The springs are BMC ST
>heavy duty and are rated to 8400 rpm. The exhaust valves are Stellite
>high strength high temperature material and the valve seats are hardened
>for lead free gasoline. There is subtle porting and polishing. The head
>has been milled to bump up the compression ration about a half point.

no_cones_ever
02-12-2007, 11:27 PM
we have a 61 box sprite and a 1380cc huffaker prepped engine...5 speed...disc conversion... yadda yadda yadda...we are running street tires and they put us in "H" stock steet tire. but maybe it just depends where you live

Hap Waldrop
02-13-2007, 08:30 AM
This is the email that I got from the head builder.

>The head I sent has been prepared for SCCA autocross regulations in D
>-Prepared. This is similar to the requirements for F_Production in road
>racing. The valves are the largest allowed. The springs are BMC ST
>heavy duty and are rated to 8400 rpm. The exhaust valves are Stellite
>high strength high temperature material and the valve seats are hardened
>for lead free gasoline. There is subtle porting and polishing. The head
>has been milled to bump up the compression ration about a half point.


Actually, in SCCA F-production, you are not allowed to run larger valves, 1.31 intake, 1.16 exhaust, and the valve spring were never made by BMC, but originally designed by David Tabor and made by Isky, since then several people have made theses springs, including past HP champ Wally Hicks, I sell Wally 's springs, but they were never made in England and way beyond what the factory or UK suppliers ever offered. As for compression ratio level used in SCCA F-production, I built heads on 1275 as high as 15.5 to 1, on 1275, higher on 948s. Oh and we don't run pump gas, more like 112-114 octane race gas, so no offense, but not much truth in his statement. Autocross and SCCA national road racing are two worlds apart.

Something always confused with our little cars, because of the rule formulas in SCCA racing, US builders have far exceed HP numbers of the UK builders. I tell my race engine customers, in a good SCCA or vintage motor, 80% of the components are US made.

healeyboz
02-13-2007, 09:16 AM
Sounds like he is not being very honest then, Hap?