308 V12 conversion begins

I did my part.

 

I thank you Sir

 

I just did a proper base line run on the head and it's up to 128 cfm at .450 lift but is at 123 by .350" lift, so it by 10 cfm but it's got a serious restriction in it somewhere......which is no surprise. I'll get to work cleaning things up now, first is to clean up in the combustion chamber on the outside of the valves and check the port cross sectional area. Lots to do.

 

I did a little more grinding tonight...the last 2 nights were too late though so tonight will be an early one. I widened around the valves in the combustion chamber and blended the seats into the port better. The result is the .450 lift is up to 136. It's a lot better but still a long way to 160. Stock was about 90 so its up 50% which should be in the 600-625 range as is though, so it's not too bad.
Image Unavailable, Please Login
Image Unavailable, Please Login
Image Unavailable, Please Login

 

Gee by the time you have ground 12 combustion chambers and 48 ports ... you will need a stiff drink me thinks . You are a very patient and clever man!

Pete

 

Wow! Bravo! All this wildly awesome hardware in a virtually stock looking 308. Beyond words.

 

The key is a lot of drinks along the way

A couple guys int he shop at work were busting my chops the other day about the "Mikes hard lemonade" visable in one of the pictures.....they didn't feel it was the most manly beverage choice. I'll have to be more careful to keep that stuff out of frame when I'm shooting the pictures.

I figure it will be about 100-150 hours of so of work to ge the heads flowing right. It's a very slow process. I'm making big gains at this phase but once I hit about 145 cfm the improvements will be down to 1 cfm or less at a time and its not unusual to find what you just did made it worse. This is not my favorite part of the project, but it's important so.....

 

Thanks.

 

Probably a silly question Mark, but do you have a completion target date in mind????

I like most here want this project to go forever as its great entertainment, but, I really am looking forward to seeing the completed project along with the mandatory video with sound.

 

Originally the date was June '08……now even June ’09 seems a bit optimistic.

 

Nice! Nice lathe chuck too. Nothing like a 6-jaw.

 

Tonight was not the best of nights. I did manage to get the flow up to 150 and I'm still far from happy with the shape/size of the port so the 160 number is still looking good. The seat IDs I have at the moment are technically for a 32mm valve, not the 33mm I’m using so I think I’ll cut the test valve down to 32mm and say that will be plenty.

Now the bad news. I managed to find out exactly were the top of the port ends and the cam galley begins....I'll nee to weld the hole closed tomorrow .

The so/so news is I just realized that edge of the oversize buckets I’m planning to use on the intake will be sitting about 1mm under the cam bearing journals. Not a huge big deal, I’ll have to increase the lobe base circles about 1mm so they are larger than the bearing journals so they stay touching the cam surface and not the bearing surface. It won’t really effect anything I don’t think but I should have seen it sooner.
Image Unavailable, Please Login
Image Unavailable, Please Login
Image Unavailable, Please Login
Image Unavailable, Please Login

 

mk e,

One of your recent photos shows a shot of the combustion chamber and valve throats. It appears you are not considering the effects of the valve guide intrusion at this stage. At what point do you begin to address this issue and how do you plan to minimize its effects?

One little trick in indentifying regions of flow restriction, that I picked up from a little book titled, "Practical Gas Flow", IIRC, made use of a small obstruction, offered into the open end of the flow port. The device consisted of a small sphere like blob (about the size of a BB) on the end of a piece of thin wire. In use, the obstruction would be moved by hand into various locations to survey the effect it had on the overall flow. A restrictive flow location would be identified as having a greater impact on overall flow than when placed in other areas. You probably already know of this technique and you may have better ones, but I thought I'd share it for whatever it's worth.

Bill

 

I made a pair of guides that drop in to give me the correct flow result, but pop out to make grinding easier. I'm probably not going to alter the shape of the guides much from OEM.....maybe a little off the sides, but I want the valves well supported and cooled.

I've never seen the bead on a stick trick. I'm still doing rough size and shape work, but in the next phase I like to put a little modeling clay on before ginding to confirm flow goes down when I add so I know there is a good chance that removing a little in that spot will make the flow go up....it's a lot of guess work, running a finger over the port walls looking for shapes that don't seem to blend, and a lot of times on and off the flow bench.

When I get the first prot to where I'm happy I'm going to try to make a few templates to help get the rest the same quickly. We'll see how well that works.

 

I'm sure Vic could get that done for you pretty fast.....

 

I'm a little off track this week converting a QV intake to EFI for another f-chatter but I'll should be wrapped up with what I can do until some part show up after tonight so I can get back on the heads tomorrow I think.

The intake cams are nearly done, just the sprocket end left (pictures tomorrow), so it's on to the exhaust cams. I'm hopeful that the rough lathe work will be done next week, then I need to drill the sprock pin holes, tap the ends, oils holes and they are ready for the cams shop and I can check that off the list.

 

Hmmm.......is someone being funny?

 

I have to believe that at this point you have something like three dozen bottles worth of shavings.....

 

I filled 3 5 gallon pales with shavings when I cleaned up around the mill and I thing there is another 5 gallon pale off the lathe from the cams and I'll probably fill another pale of 2 when I start the cylinder liners....there's chips everywhere





Oh, and btw, anybody thinking about converting a QV/328 intake to EFI.....it's a pain in the *ss becasue the throttle body gets in the way of every good (easy) idea......back to my head for a bit while I think about the manifold problem a bit and run the options by the owner.

 

throttle body spacer . . . BTDT . .. but like to hear what performance gremlins might lurk 'cause of a 1.5" + long spacer? Sure makes the EFI conversion easier though

edit: solution #2 rotate throttle body 90 deg and re-route throttle cable

 

The QVs are worse than the 2V because the injectors stand straight up it seems. I think I'm going to completely remove the OEM bosses and weld on new ones about 1 3/8" lower......maybe.....
Image Unavailable, Please Login
Image Unavailable, Please Login

 

Buh-bye hole in the port

I also cut the valves down to 32mm, cleaned up the port a bit more and the flow is up to 153cfm @10" H2O, 7cfm to go. The flow velocity is also up 25% which is pretty good. I'm pretty sure a proper valve job will gain me 3-5 cfm, so really I only need a couple more and I'll be happy....and it should be a 750 hp engine
Image Unavailable, Please Login
Image Unavailable, Please Login
Image Unavailable, Please Login
Image Unavailable, Please Login

 

2Vi manifold is simply drilling holes, even I can do that but of course I went through the wall. That isn't to bad though because the injectors don't seal with the lower O-ring anymore (to deep) so I need sealing rings in the recessed area of the bigger part of the injectors.
Image Unavailable, Please Login

 

That's what I though the QV manifold was too....stupid throttle body

I've got the injectors sitting as low as they can go without losing the lower o-ring surface to seal, but it ait low enough.

Of course I couldn't resist cutting all the big part of the boss away.....I probably saved 2-3 ounzes
Image Unavailable, Please Login
Image Unavailable, Please Login

 

you actually don't even need to do that on the 2V . .. I made adapters that just screw into the old hole . . . you don't even have to remove the intake to install my kit

I also posted a pic on what I was thinking on the 4V but don't have a motor to see it thru yet . .. anyone ready?

Keep up the mods' boys!
Image Unavailable, Please Login
Image Unavailable, Please Login
Image Unavailable, Please Login