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Posted by: Matty900 Jul 25 2017, 07:48 PM

I just got a call from a engine builder talking about rocker arms. I may have misunderstood him but I think he said that the guy that did the cam for him suggested that if we could get a 1.3 to 1 ratio rocker arms we could get more out of the cam. I know enough to know what I don't know any of advicece would be appreciated.
1.7 being built to 1911 with dellorto 45 carbs

Posted by: Mark Henry Jul 25 2017, 09:39 PM

Type 4 stock rockers are 1.3:1

Type 1 stock rockers are 1.1:1

Posted by: Matty900 Jul 26 2017, 12:07 AM

I'm getting nervous about this guy.

Posted by: Tbrown4x4 Jul 26 2017, 02:40 AM

Thanks! I have been trying to decide on a cam, and 1.3:1 was mentioned. I didn't have a chance to post the question yet.

Posted by: Mark Henry Jul 26 2017, 06:06 AM

The cam grinder should know that the stock ratio is 1.3:1, in my book so should the builder.

I'm not perfect, I make knowledge mistakes all the time about other aspects of 914, but I specialize in engines, so that I know. If you builder does lots of type 1 engines he should be OK on a T4 stock build, but this is not a good first timer engine unless you are very careful and take the time to learn.

Posted by: McMark Jul 26 2017, 10:09 AM

Yes, that's a huge red flag, IMHO.

Posted by: porschetub Jul 26 2017, 05:36 PM

same as fitting 45mm carbs on a 1.7 .