-90 Burb is going to get the C

[ttammeslehto]

Head Revisited

Been finishing and polishing runners on last week and looks like it's going to take week or two more before the head is done what comes to the runners, then it's time to measure the "combustion chamber" and match them also.

Some pics of the runners may be on my page after few days



http://samba.student.oulu.fi/~jpontys/Kapy.html



Timo

 

[HoleshotHolset]

Timo: Lookin' good! Thanks for the update!



Matt

 

[ttammeslehto]

Exhaust side DONE

Something to celebrate, the exhaust runners are ready to rock & roll.

Now only the intake runners and plenum area needs a minor work, then it's time to go to a shop for a slight milling and continue work with it.

Hey HoleshotHolset thanks for the comments. It's been surprisingly quiet what comes to the comments from others, maybe they just sit back and watch.....

Anyways here's the link for it .

http://samba.student.oulu.fi/~jpontys/cummins.html



Timo

 

[cjohnson1]

Timo

It's been surprisingly quiet what comes to the comments from others, maybe they just sit back and watch.....

Keep your chin up Timo. We're reading every word. Just hard to type with our jaws on the key board. Very nice work. Brings back a lot of memories of the days when I had more time than money and the patience of a Saint!!!



Very very nice. I especially like the flow bench. It is a shame all that work will never be seen inside the block. But, the results will show up everytime you step on the skinny pedal.



C Johnson

 

[ttammeslehto]

News

Chin's up all the time ;-) it's been a quiet time what comes to my project, been busy with other things. I opened my gasket set (FelPro) and when comparing the gaskets fire rings and sealant stripes to Cummins original I decide to order OEM gasket, I also mailed to PDR and asked their opinion which was the same, use Cummins gasket. I'm on a process to get the head O-ringed but my machinist say, they can't do it..... hmm, maybe I need to figure out something by myself

... By the way, PDR cam/lifters, high flow delivery valves, 3000rpm kit, AFC spring kit arrived a some time ago. I found also a HX-40 with 16cm2 housing from Ebay, so, looks like all the big things are purchased now, except the IC ofcourse but the point when that's needed is so far away... ... BTW the pics of the gaskets are on my page, if you like to compare FelPro and oem.



Timo

 

[Alaskaskiff]

Nice work on your project.



Another Finn here, only 50 % though. First generation US, however.

 

[banzaitoyota]

The reason I have not responded to this great thread is I don't want to clutter it up, but GREAT WORK!!!!. Keep the pics and write-ups cummin!

 

[ttammeslehto]

Groove, Babe

Hey, I don't mind if someone clutters up but your are partly right, the thread has stayed "clean" and in easy readable form. 20 to 50% Finns seem to be allover, maybe it's in our genes, "Gearhead", leave the home and go to a "promised Cummins land", where horse power is for breakfast

and torque for lunch... ... . to be honest, I have had that feeling a looong time, hmm..... let's spread the word, anyone wanna hire a computer goof/ total diesel nut



Then to the business, here's a few words where I have wasted my freetime lately (wife's opinion) been working with the head by doing O-ring tool, I'm not so proud of it, looks like a cave man's tool to me... but I got the grooves done with it, check the page. http://samba.student.oulu.fi/~jpontys/cummins.html



Timo

 

[AKAMAC]

Just to add to the clutter... ... .

All I can say is WOW I (in my youth) took a sleeve and piston from a 750cc Honda, bored the lower cases, moved the oil orifice, ported and polished the head, to convert a Honda 100cc to a 185cc in 1977.

Timo you are the man!!!!

Wish I still had the patience to do the machine and TIG work to make a project like yours.

Keep us posted and get some pics of first smoke. Oo.



Mike... ..... 50% Norwegian

 

[ttammeslehto]

Head and valve job

Quick update, I get the head with valves this morning to my machinist to a slight milling to get a fresh surface and to make sure that it's straight,

they will also do a valve job with 30 degrees back cut to improve flow. Too bad that I forget to take a pic of valves before taking them to shop,

the valves had a sharp notch in the back side of valve disc, which 30 deg. back cut will remove. More pics will be on my page when I got the head back

from the shop, around end of the next week.



Timo

 

[ttammeslehto]

Hello for a long time...

I have been basically just washing parts these weeks, that's the reason for no update, I think you guys had seen parts washed before,

so why bother, anyway they call me from machine shop and my head is ready to pick up, will do that on tomorrow and continue to work

with it. They regrind valve seat's and valves with 30 degree back cut etc. thus I need to at least smooth out all the sharp corners as well as finish the valves.

I'll took some pics, when ones again I start the grinding... ... ... ...



Timo

 

[HoleshotHolset]

Timo:



What kind of finish work are you doing to the valves?



Back cutting does wonders to get the air in/out of the head.



I had the valves back-cut on a Chrysler 2. 5L I-4 head (along with 3 angle valve job... ) and the airflow improvement from that along with a little bit of port/bowl work was HUGE.



Make sure you get a flow bench test on your before/after results - it helps to justify the cost and effort involved.



Matt

 

[ttammeslehto]

At least for the exhaust valves front face to margin area needs to be radiused, I would like to also smooth out the edge after 30 degree back cut.

Some race valves have a swirl pattern on the intake valve... hmm wonder if that would make any difference.

Anyway I'm picking it up today but I'm busy with other things until next week.



Till then



Timo

 

[HoleshotHolset]

I wouldn't bother with changing the intake valves to have a swirl pattern.



At 100psi of boost - the little things like that don't make much difference.



Matt

 

[ttammeslehto]

Yea, well let's see how things turn out, maybe I'm too lazy to do the swirl... ... write now I had a terribly flu and I need to get myself somehow to the better side, since Friday one guy brings his Firebird for http://www.espar.com/ installation and I promised it would be ready during the weekend, I just got to make it. On next weekend is a trail Saturday and I definitely want to go with my Jeep..... I maybe crazy but I can't help it.



Timo

 

[HoleshotHolset]

Best wishes for a speedy recovery.



There's lots of nasty 'flu-type' illnesses going around.



Matt

 

[ttammeslehto]

Head/valves are back

And I'm feeling better after spending a Saturday on a trails, that was a good one

,I didn't broke anything... . so I'm able to continue with the Cummins, yesterday I cleaned up sharp edges from a fresh valve job and going to spend a evening or two to finish the head and lap the valves in a real life rest of the week... ...

almost forget, on the page,there are few new pics, just valves and head



Timo

 

[HoleshotHolset]

The exhaust runners on your head look very nice!



Wow! - You cut your own o-ring grooves... ... You're a lot more brave than I am!!



Keep up the excellent work!



Matt

 

[ttammeslehto]

The world of swirl

Yea, even I think the runners are cool... ... I did cut the grooves by myself since my machinist said they can't center the tool for cut the grooves, but there are old gasket marks clearly visible, I said, use them to center the tool... no luck.

I think the biggest reason for was that they can't just put the head on their machine and press a button... I'm sure you know

the feeling when trying to get them to do something what is not a everyday thing, it scares them off and you get a bit

pi**ed off... . heh. . heh. anyway, I cut them and then took the head back to the shop for a valve job, you should see them

faces, I enjoy every minute... okie enough bull shooting. I just finished the valves, smoothed out the edges what where

left after the back cut and on the exhaust valves I radius the front face to margin area. The pics should be on my page on Monday. btw if someone likes to get a good readings for the bed, I would recommend books from David Vizard, his powerpro

series, they are the good ones... .



http://samba.student.oulu.fi/~jpontys/cummins.html



Timo

 

[ttammeslehto]

We had some technical problems with connections but now it's ok and pics are on the page.

http://samba.student.oulu.fi/~jpontys/cummins.html



Timo