4jg1t "franken-engine"

[paulthepilot5]

handymanny01 wrote:Yes, 5 x 0.22 mm that's the DLLA144PN309 (4jh1) And 4jb1 is typically DLLA154PN (XXX) 4 x 0.28mm , (several different nozzles) so yes, you're totally correct that (area wise) , the 4jh1 are smaller,, However.. In my application with the custom pump,, The 4jh1 injectors were CHUNDERING out fuel... HUGE clouds of grey smoke,,, So fuel was def being delivered, but the spray angle didn't suit the 4jg1 pistons ,and is wasnt burning properly ,, they are a different profile to both 4jh1 and 4jb1.. going to build up a 12mm pump "based" on a standard 4jb1 now though, And match nozzles to my pistons.. I DO like your idea with the banjos though! Might even be able to machine circlip grooves, and use them to retain banjos with o rings ?? This is why it's GREAT to bounce ideas around with like minded people! I totally hear ya that on paper going for the 6 cylinder excavator nozzles seems like a lot of effort for same nozzle size,,, but as this 4jg1 hybrid seems to be very particular on spray angle,,, I have to at least try the 152 degree nozzles! yep ok, forgot the JG1 was another style bowl. One other thing to play with is your injector height in the head. You can use 4H1E1T copper injector seals, same profile and diameter but about 1mm shorter.

[handymanny01]

Cheers Paul, yes I have access to several different height injector washers, plus my own brass shims too,, I tried raising and lowering the 4jh1 injectors when I tried them,, Made noticeable differences to the smoke level,,, but power remained similar,,, it maybe just shifted the peak around ?.... but then they were really not the right injectors for my pistons,,, so who knows really? I've sourced 1.5mm copper sheet for the gasket now,,, So just gotta draw it up,, and get it water jet cut.. then machine head for o-rings,,,, Then I can try again!! Lol. The other parts of this hybrid build are in perfect condition though,,, pistons, head, valves , hybrid turbo , bores,, all mint,, so that's pleasing at least ! Hahahaha.

[jackapoo]

is there any news on how this build is going??

[handymanny01]

much news! some good some bad,, lol Yes its still going! so it got water methanol this year,, and 4JG1 single spring injectors.. power dropped off a bit with the single spring injectors, dynoed at 90KW at wheels and 411 NM (on 33'' wheels mind, so still not bad) then 115kw / 495NM on 50/50 water meth,,, then a whopping 133KW 510NM on 25/75 water meth,, needless to say, it felt pretty grunty! that was running at 29 lbs boost... The whole project has been hampered by the mods i made to the pistons (de-lipped) which means it won't ever run to its full potential until i build the next one with un-modified pistons... I've been having to run excessive advance to combat the poor burn, which causes excessive "nailing" and has ultimately ended in a snapped crank, (no 1 big end) a very old harmonic balancer , and over tensioned belts, prob hasn't helped here either... important to note this wasn't a power related failure, it failed under light load and low boost.. although the standard aluminium big end bearings weren't up to the job, so these have been replaced with copper lead bearings...
Its now back together with a new (second hand) crank, new solid copper head gasket, and running brand new 4jb1 153 degree nozzles in twin spring bodies... and its going great! seat of the pants says 110kW and 500 nm.. so will book dyno again, and put results up...

[handymanny01]

One broken crank! waaaaaa

[handymanny01]

solid copper gasket - O ring head mods

[paulthepilot5]

handymanny01 wrote:solid copper gasket - O ring head mods
What are you planning for a crank upgrade? I haven’t gone the copper gasket or o-rings yet, ARP studs are holding the factory gasket ok.

[paulthepilot5]

handymanny01 wrote:much news! some good some bad,, lol Yes its still going! so it got water methanol this year,, and 4JG1 single spring injectors.. power dropped off a bit with the single spring injectors, dynoed at 90KW at wheels and 411 NM (on 33'' wheels mind, so still not bad) then 115kw / 495NM on 50/50 water meth,,, then a whopping 133KW 510NM on 25/75 water meth,, needless to say, it felt pretty grunty! that was running at 29 lbs boost... The whole project has been hampered by the mods i made to the pistons (de-lipped) which means it won't ever run to its full potential until i build the next one with un-modified pistons... I've been having to run excessive advance to combat the poor burn, which causes excessive "nailing" and has ultimately ended in a snapped crank, (no 1 big end) a very old harmonic balancer , and over tensioned belts, prob hasn't helped here either... important to note this wasn't a power related failure, it failed under light load and low boost.. although the standard aluminium big end bearings weren't up to the job, so these have been replaced with copper lead bearings...
Its now back together with a new (second hand) crank, new solid copper head gasket, and running brand new 4jb1 153 degree nozzles in twin spring bodies... and its going great! seat of the pants says 110kW and 500 nm.. so will book dyno again, and put results up...

Old harmonic balancer will do that, mine snapped with a loose balancer. New one on now and it’s been fine. You would have had some crazy advance timing running 25/75, even 50/50 will advance too much if you get carried away. Probably best looking at running a lower comp ratio of you want to do that.

[handymanny01]

That's interesting you should say that Paul, as all my research suggests that methanol actually retards the combustion event , due to its low Cetane rating, ie it is slow to burn, and has a high auto ignition point,,, Further to that, methanol will ONLY burn once the diesel has ignited , it will not burn with compression alone, I think the issue (in my case) was I was already running excessive advance, and the better burn I got with the water meth, resulted in excess peak cylinder pressure, worth noting this "only" blew a head gasket, it didn't break the crank, the water meth had been turned off for weeks prior to the crank breaking,,
As for the crank, no plans for anything but stock crank, it's crazy strong, I had a go at my old one with a huge hammer for "research purpose" and they are TOUGH!!

[handymanny01]

On a side note Paul, you may be interested to know, when I built this thing with Alibaba pistons, I got them hard anodised locally, and can confirm TOTALLY worth it! I'd rate it as 2-3 times better than "ceramic coating" ,the anodising "grows" out of the aluminium, it cannot flake or chip off,, And after 3 blown head gaskets, and a broken crank worth of abuse, there isn't so much as a hint of colour on the underside of the pistons! And the crowns are 100% like new! Very impressed,, I actually tested some factory pistons before I had mine hard anodised, and the only way you can get the anodising off is sand blasting , Obviously just my opinion, but though you might find it interesting : )