Damo, not that it matters much to your engine, but maybe an engine like this could use less oil pump? Seems to work for the Iron Lion V8 Holden fellers who suck thier sumps dry at the drags...?
Muffler mike in the USA did some video testing (on his site) to show that the crank slings a lot of oil up the pushrod tubes on the left side of the engine.
He also found that if the drains were in the ENGINE CASE on that side, that they added to the problem.
So by putting them in the sump as Daimo has, is actually better in this instance than being at or above 'high tide'.
Mike ended up putting his drain around the engine and into the other side of the engine,
and it seems to have worked.
This is of course a straight line racer, so a car that makes corners will most likely need help on both sides as Daimo has done.
I have a 26mm pump on my engine and only with the larger journals and extra oil clearance of the "blower" bottom end(70mm main bearings and 56mm rod journals)
did I consider a 30mm pump.
In the end I went up to a heavier oil grade and it is now OK.
On the back-up engine with 60mm mains I use GTX3 and it has excellent oil pressure and
never lacks sump volume.
Yanks use a small scavenge pump(autocraft) on the left cover to keep the sump volume in check....semi-auto pump would work well if I did not have a mechanical fuel pump to drive.
good one Dave, it takes a while to drain away doesn't it.....
a couple more bits to be done to the valve covers.
spent the best part of my day setting up some tabs to hold the gaskets from "sucking in"......and some baffle plates to go over the breather holes.....
braised them into position ........
cleaned it all up.....
job done
i also made a little video in the parts washer of just how much flow those drains can handle.......kinda ties in with what mufflermikes vid linked above showed us🤓
i had a bright idea after a couple of 'ol favourites to rebuild my 48's........
first step was to get all the bits organised....
yes that is the kitchen table, ready to be put to good use😎
here goes the tear down........
out with the main jet stack.....
out with the idle jet holder.....
behind the fuel inlet union is a small filter screen. i'm running a center T pressure regulator, so i only have one pipe fitting on both sides.
removed accelerator pump push rod.....
accelerator pump diaphram and spring, YUCKY!!!(storage issues)
mixture screw/spring/washer and oring, need to dig a bit to get them all out.
the air by-pass screws are used to get final sync between ports. they allow air to bypass the butterfly plate for very fine tuning. often siezed up🙅.....you can see all the progression well ports now the cover screw has been removed.
progression ports/mixture screw and bypass from inside. you can see where the butterfly opens gradually pass the ports.
we're aiming to get in there and change the main venturies/chokes........
auxillary venturi and accelerator jet need to come out of the way......
pump jet has a flat side to ensure installation with the hole towards the engine........
out with the five top cover screws.......
...giving access to the float and bowl....
i'm using bergs ball type fuel inlet valve (needle and seat).the float arm had to be bent out of the way to install.
compared to dellorto needle. a tad more flow with the berg:thumb
and full flow is achieved with very small float travel. the large ball actually pushes a much smaller one into it's "bowl" above.........positively stopping flow when closed.....
the float assembly needs removing to replace the top cover gasket.......
why so much concern over a special needle and seat????.....well the dellorto fuel bowl is not overly big, achieving maximum incoming fuel (without big pressures!!) will allow wide open throttle for extended periods before running the bowl dry🤪
at the bottom of the the bowl is the accelerator pump valve........
the pump valves small galleries are a good place to start looking for dirt when your dells are running up tha' shite🤘
with the carb top off, access to the accelrator pump weight and ball is gained.......these cut off the gallery that runs up from the pump diaphram to the jet
undo the lock nut and locating screw for the auxillery venturi.........
and out they pop.......the have a oring seal and must be replaced with the angled side running down for proper operation....
loosen the main vents' locating grub and out they go.....
no it's cool, that's why i'm doing one at a time..i can always reference back to the untouched one if things go really bad. anyways all the jets and screws only fit one position and one way, toooo easy:kiss
different size chokes will provide different vacumn signals through the secondary venturi.and advance the fuel at different rates verse rpm. smaller chokes work well down low, with top end sacrifice, biggens will flood down low in the rpm, only to come on later....i'm going for the 36mm in the middle which should be good up to 6700rpm🥷
easy to see how they change flow characteristics thru there.........smaller on the right🤖
changing jets is easy,,,once you locate some. i've gone with a 50 accelerator pump jet......spring loaded into it's holder
65 idles.......everythings been scrubbed and blown now and i'm replacing orings as i go.
air correctors, emulsion tubes and jets are interchangeable with dells. 190 airs, and 155 main jets
fast forward in a productive direction..........
rubber top gasket installed and float level set....
new accel pump diaphrams and springs loaded up.......
the ledgend goes that a 3 thou gap is good enough for start up.....done on both carbs it should provide reasonable sync for inital start up.........all mixture screws were wound in (gentle!) and backed out 2 1/2 turns for a starting point.
ready to go again. no time for EFI if i'm going to Warrick, the race has already started...........😉
Hi Daimo,
can you list what jetting you will start with ,
and 'why',
to go with the 36mm venturis.
What Idle jet and accell pump squirter also.
Thanks,
DB.
o.k......so the decision on venturi size was made with the following graph. i'm looking at running up to 6000rpm, maybe some more.the usual conversations with anyone who would sit still long enough to listen to my babbling, backed up the idea for this size (as well as jet sizes). i would have liked to help tame my lead foot, by running the 35mm and rich jetting for starters, but with Warrick coming quickly, went with what i thought would be closer to my ideal set up as far as drivability versus performance
from there the "formula" says to multiply vent size X 4 (for vent sizes up to 36mm)to get a main jet size.
after 36mm venturis, multiple by 4.2........:duh
so that left me going for 4.2 X 36mm and so 1.51 mains. i moved up to 155's to start a bit richer.
i've also gone for 190 airs in an attempt to slow the fuel onslaught expected from 48's once they get open wide, and onto the main circuit. again thoughts of my small capacity prevailed over what would be the more "normal" 180 air correctors
idles were a chuck up, between whats recommended for the smaller dells (and my small capacity) and the phatty's normally used in 45's and 48's...........so the 65 idles i went with were in the middle of what i found people to be using/reccomending (55's to 70's).
i knocked the pump jet back to a 50........it was previosly 60, and stomping on the throttle with the 2180 seemed to flood it...........
that's about it, i won't be afraid to mix them up once it's running, with such a wide stash of all the changeables,it should be fun. i'm hoping the air/fuel sensor (3 wire heated type) and guage will help the process along, i'm quite looking forward to it after seeing just how much difference even a small jet change can make after spending some time playing with 'lil sissy's 36ers lately....
mind you, a chat to Ben about haltech's latest and how they tuned Heaths car with the exhaust sensor and data logging alone has me amped for fast tracking injection🥷
awesome build! Which i was as handy..
do you have any more info on the throttle bodies - like make, where ya got them.
I'm tossing up whether to go for carbs or make the jump to FI..
ooorkay, with the carbs sorted at home whilst baby sitting during the holidays, it's time to get serious again.......
1.45 rockers:duh
the arms were all free with side play present, but bolting them straight up, it was obvious there was at least one arm running too tight......
cleaned up and checked out, setting the side plays was easy with a combination of shimms and sanding the thrust area of blocks and arms
this got the arms centered over the lash caps/valve ends, with the correct amount of play so when bolted up (as above), they all "flopped" down via gravity alone, BUT with minimal side play.......
however, the starting point of the arm is too high on the valves......
and only runs higher with more lift.......
this was common on all valves, both sides of the motor. it looked like being a problem with the 1.54 rockers i had a few pages back too, but didn't need to be sorted then as the lift amount was too great for my set up.......BUT now it does need sorting!:o
blued up the caps to make sure i wasn't imagining it
DAMN! too high!........and won't help at all with the longevity of the valve guides because running like that will add unwanted side loads......
anyways..........a full check of all the lifts reveals 13mm accross the board..so they really are 1.45's this time around...........:thumb
substituting another set of rockers made no difference, the problem is steming from the heads and lack of valve stem length
unfortunately (timewise) the heads need to come off to mill the rocker pedastals down so to have the rocker arms at more angle and as such, their "swipe" operating area moved closer to the center of the valve ends..........
😠
good chance to check i had the pistons in the right direction. one of the best reasons for loads of pictures, to me , has been the ability to double check things that become unaccessable during the build. i have peerred through the spark plug holes at these, after some sleepless nights before😊
This disclaimer does not reflect the thoughts or opinions of either myself, my company, my friends, or my dog: don't quote me on that; don't quote me on anything; this disclaimer is subject to change without notice; text is slightly enlarged to show detail; resemblance to actual persons, living or dead, is unintentional and coincidental; dry clean only; do not bend, fold, or mutilate; anchovies or jalapenos added to this disclaimer upon request; your mileage may vary; no substitutions are allowed; for a limited time only while supplies last; offer void where prohibited; this disclaimer is provided "as is" without any warranties expressed or implied
in an attempt to keep moving forward, AND motivated🤪 the opportunity to takle the tinwear clean up, whilst the engine is again apart, was taken up.
finished the dimple on the tin for the oil return fitting...
don't wtch this space for radical colours or chrome. if something can be painted black, i will most often do just that...........the manifolds and air cleaner tops have already had a narrow escape🤘
bar at front is engine support/hop/traction set up
one very welded fan......
spotted some heads around the traps with fins missing, and tales of exploding fans jamming throttles wide open influenced the decision to grab one of these😎
back to bare metal for you lot!
porting the exhaust was finished too, off to the ceramic coaters
Cram, no prizes for guessing what brand T.B's or where they come from.........you should get both answers in one go🙄 they are 52mm butterflies
koolkarmakombi....it will just be a small amount at a time, on one head, we are thinking 1-2mm should do the trick............at the end of the day,rocker stand shimms can be used to get some height back anyways, although i'd rather not need em. the lift on both sides of the motor was within 0.085mm accross the lot (indicating evenness), so the same amount will be taken from the second head once the first checks the problem
This disclaimer does not reflect the thoughts or opinions of either myself, my company, my friends, or my dog: don't quote me on that; don't quote me on anything; this disclaimer is subject to change without notice; text is slightly enlarged to show detail; resemblance to actual persons, living or dead, is unintentional and coincidental; dry clean only; do not bend, fold, or mutilate; anchovies or jalapenos added to this disclaimer upon request; your mileage may vary; no substitutions are allowed; for a limited time only while supplies last; offer void where prohibited; this disclaimer is provided "as is" without any warranties expressed or implied
with sandblasting, strip discs and wire wheels (OUCH!) it's all back to metal........i can't say this was at all fun 🤪
.......but a necessary evil to avoid using after market tins.
the quick option being long gone, i'll etch prime it all before, smoothing and paint.........never again🙅
this might help understand prefrences for german tin. some of the air deflectors tabs were broken off in the repro fan housing, although not completely free. they're not going anywhere now Mr MIG has paid a visit👍
..also set a "pad" in place for the carb linkage, will tap a thread in there for the third mounting bolt.
I've stripped quite a few bits of tinwear in my time - I know how much of a shitty job it is mate! Messy too.
Have you decided to go two pack for the tins or another method? I'd be happy to do it for you for no cost to repay the favours you've done for me.....wish I lived closer and warwick was further away! The offer is there if you need it anyway.
alas, you have enough to do i think, so i'll get there.
thanx heaps for putting it out there
Dave kicked butt on that tranny of yours sooner than i thought so those bits will be on the way tomorrow Allan
i still reckon i should just truck this sucker up and slot it in the back of your oval for the weekend😏..........i'm heading to do a bit more now, after daily grind commitments are filled, i'm effectively down to 60 hours till Warrick🥲
I have lots of painting to do between now and end of Aug so trust me, if you can get them up here, I'm happy to do it. You've done the hard part (stripping and cleaning!). No probs if not though, I won't be offended.
