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Discussion Starter #1 (Edited)
i,am going to port and polish the 4 bt head & exhaust manifold on my 4 bta . also getting ready to do complete rotating assembly balancing to within a gram.
i,ve been port & polishing heads for 25+ years, even on semi truck heads with great results.
bob in tn.
ph.# 1 423 384 8938
 

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I've debated whether porting, polishing, and balancing realizes any significant performance gain. Any idea what kind of results you'll get? I'm currently freshening up my engine and I struggle if it's worth the expense.

Thanks
Bruce
 

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Discussion Starter #4
every performance engine has trick heads and you better know what your doing when you start grinding. it takes alot of different burrs, discs, cartrages, mandrels, grinders etc. to do it right. go too far and you,ll hit water........
 

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water water everywhere

You obviously didn't look at the link. The link shows you how to match a manifold to the head and aslo to the turbo so you are only porting the exhaust manifold and unless its a marine manifold there should be no water there.

Gaza:innocent:
 

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Probably all you need for a low revving diesel. I appreciate there is a lot more skill involved flowing a head for a high revving gas engine or even a money no object sled puller. The link is for people wanting a little extra for no cost.
I personally think that at the revs we will be driving most of the time it will make virtually no difference. If I had the skills and tools like you have then I would probably do it just for the hell of it. So in answer to your question ?????...NO

Gaza:jester:

PS how much do you charge for a port & polish?:smile:
 

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Efficiency & cylinder filling go hand-in-hand even at low rpms . The better you can make a motor breath the more low end torque you'll have & better fuel economy is acheived also . ( Motor doesn't have to work as hard ) I've wondered how these 4b's would run with a good port job. I would think it would also need a different governor spring for some higher rpm's .
 

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You obviously didn't look at the link. The link shows you how to match a manifold to the head and aslo to the turbo so you are only porting the exhaust manifold and unless its a marine manifold there should be no water there.

Gaza:innocent:
so when you posted a link on exhaust porting in a thread on head poslishing you obviously didnt read the thread title, or the accompanying words in the previous posts. had i been the thread starter i would assume your link would have to do with my subject matter. but hey what do i know
 

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I would have thought that a link to a site showing you how to match exhaust manifold to exhaust ports was relevent in a thread entitled ported & polished heads.

Gaza
I totally agree. I found your post very relevant and plan on doing it. I have a hard time understanding why matching the ports in the exhaust housing to the exhaust ports in the cylinder head isn't related to "ported and polished heads". Granted, the head port itself isn't being changed but it helps improve the flow thru the head.
 

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Bob, I'm curious about your price on a 6bt head port m'self. I was thinking of just a gasket match, but if you're getting any decent gains at all it might be worth it. I drive about 50k a year, so any mileage increase especially is of interest to me. :)
 

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Discussion Starter #15
port& polish

taco, i cant sell on this board so you,ll have to contact me off this site. sorry.
bob
 

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sorry I hope you guys understand about this.. Bob had a bunch of motors and was offering a porting / polishing service for about a grand.. I have broken even for now but setting up/running a site takes time and some $$ and we figure guys out there making decent money off sales can pay $75 and advertise here.. If you are an individual, different story.. Pirate is $100, mud is $150, I figured $75 was pretty cheap... :confused:
 

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sorry I hope you guys understand about this.. Bob had a bunch of motors and was offering a porting / polishing service for about a grand.. I have broken even for now but setting up/running a site takes time and some $$ and we figure guys out there making decent money off sales can pay $75 and advertise here.. If you are an individual, different story.. Pirate is $100, mud is $150, I figured $75 was pretty cheap... :confused:
Fair enough. Bandwidth ain't cheap.

Bob, PM sent. :)
 

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Discussion Starter #18
update

this site i feel is going to boom and i plan on supporting it all i can. also i do plan on paying the 75.00 ( very reasonable ) when membership grows to a point where it becomes viable . i,am not a dealer just a guy who owns a semi truck repair shop. the 4b engines is just my hobby. i mainly do 4 b installs on kaiser jeep army M715 trucks as a hobby . I,AM NOT INTO THIS FOR A COMMERCIAL BUSINESS... it just so happened i got offered a lot of engines in various stages of condition and i bought them all for my conversions. people found out i had them and started asking me to sell em one ... knowing what i do about diesels they trusted me to get them a good rebuildable core . this is a tremendous blessing to have a nice friendly place for everyone to share about some thing we all have in common the b engine and i for one am very grateful to be here . KEEP UP THE GREAT JOB......
BOB IN TN.
 
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