john deere 70- 730 diesel

[Brad Vinkemeier]

This message is a reply to an archived post by buickanddeere on February 03, 2009 at 19:41:14.
The original subject was "Re: john deere 70 730 diesel".

what about if u have the 730 head poted and polisded cleaned up the bowels larger valves manifold port blending all done which head will flow more the 730head or the same work done to a 70 head
 

[Brad Vinkemeier]

What is back cutting the valves do also
 

[diesel puller]

The 730 head part # 3511 for the simple fact that the injector tubes are casted in the 70 with 3211 head have brass inserts which will leak pain to deal with and $$$
 

[buickanddeere]

Which 70 head? The original 70 heads used smaller valves and tended to crack. Most were replaced with 720 heads.
 

[Brad Vinkemeier]

Buickanddeere i also was wondering how do u fit 820 or 830 intake valves in a 730 head its darn tight as it is i do not know whe how much bigger the 820 intake valves are and what do u do with the eyebrow on the one side do u just clean it up or do u remove it completely thanks for the information and ideas
 

[buickanddeere]

Careful measuring and grinding to remove a minumum of material.
 

[Brad Vinkemeier]

By how much bigger are 820 valves over 730 valves
 

[buickanddeere]

830 uses 2.075" and 2.605".
The 70 uses 1-29/32" or 1.90" and 2-3/8" or 2.375" valves.

So the intake valves will move out 115 thou farther.
The exhaust valves will move out 87.5 thou.

Ain't gonna run out of room.

Valve size isn't everything. Cam timing, port blending and multi-angle seats are major players. The shape of the intake valve matters too.
 

[Brad Vinkemeier]

Yes i know but thanks for the specs i was planning on having that all done also thanks again