yesOriginally Posted by Turboman
yes
i got dog on the dyno, a couple of minor glitches and i had it running, but then it all went a bit pete tong. the servo motor which controls the water output from the absorber and therefore the load applied to the engine packed up so i could run the engine but not actually test it in any meaningfull way
old servo motor and most of a stripped valve body. i got a new valve and rebuild kit for the valve, i ordered them Thursday from the USA by Tuesday i had them, i was just another £1500 poorer.
new motor and valve re-installed.
That's another 2 dyno sessions you'll have to do for customers Graham just to cover the valve cost.
i got dog on the dyno, a couple of minor glitches and i had it running, but then it all went a bit pete tong. the servo motor which controls the water output from the absorber and therefore the load applied to the engine packed up so i could run the engine but not actually test it in any meaningfull way
old servo motor and most of a stripped valve body. i got a new valve and rebuild kit for the valve, i ordered them Thursday from the USA by Tuesday i had them, i was just another £1500 poorer.
Be very quiet please! Lol
Does seem a ridiculous price though for a servo motor
https://youtu.be/lZ1TC0lot30
first pull!
i was well chuffed when finally i got the dyno to do a power run, at that stage i hadnt got my head around the windyn software enough to have the computer do its thing and actually record the power run or any data. i was having issues with the hydraulic throttle and getting it to work the carb linkage so i wasnt getting full throttle, even so dyno Dog was making over 90lbft and about 100bhp. Couple of days later i had full throttle but had lost a bunch of power, i thought i found it, the brass tube in the secondary aux vent had moved and blocked off the fuel supply, finding it involved a load of head scratching. what i havnt said is i was monitering the barest minimum, load (dyno servo position) torque, rpm, oil temp and coolant temp, i hadn't connected up oil pressure as i knew the engine had oil pressure and if was low i wasnt going to do anything about it anyway ( more of that point later) i hant yet got any way to check AFR, but given it was a standard engine with a standard carb there was no real need, or so i thought! carb fixed i still only had about 80bhp
Last edited by Graham; 14-02-2021 at 22:00.
Big progress there.
that did include a rebuilt kit for the valve, but stuff from superflow is very very pricey, diaphragms for the throttle are £30 each!
Good progress wether it’s good or bad for Dyno dog as let’s you know what your looking at! Maybe if you lost oil pressure you would have shut down a 10k engine (just hindsight) lol
one thing im really pleased about is the cell itself does a good enough job of keeping noise down that despite sitting only 6 foot away the other side of a thin wall and door my wife can tolerate the noise of dyno pulls, and from outside the building it sounds like a car being given some beans somewhere in the distance. the guys in the business next door didnt even know i had been running it. well at least thats the case with a standard pinto on a twinchoke, might be a different matter given 8k and a pair of sidedrafts!
i wouldnt consider running any other engine without monitoring oil pressure, but i knew it had oil pressure and im really tight on time for another deadline, i have a v8 rover engine that i need to test and refit in its car before the owner takes it back to america, so spending time making up oil lines and adapters for a pinto has to wait.
back to dog and its missing power, i checked a load more stuff, none of which was wrong, did another couple of pulls and i was down to only a little over 70 bhp!!! torque was absolutely falling off a cliff @4,000 i was sure it was mechanical, but just to be sure i decided to do an ignition timing check @5000 rpm, the dyno makes it easy as you can hold the engine at a lightish load at a very stable rpm, it was slightly more advanced than i expected so i decided to back it off a bit, still engine doing 5k, a couple of tweeks and it was right, but suddenly i had oil absolutely pissing out the head gasket at all three oilways! the only thing thats going to do that is the oil pump pressure relief valve getting stuck shut. so i whipped the sump off and chucked another oil pump in it, swapping the oil pump picked up about 5bhp, heaven only knows how high the oil pressure must of been but it must of been immense, i didnt change the head gasket when i did the pump, but oil leaks from it have gone. i did a bit of rejetting based on plug colours and power output, played with the fuel pressure reg and got it upto 85bhp, im short on dgav jets so current jetting isnt quite ideal, judging by the plugs it could do with a bigger primary main and smaller secondary, so theres probably another 1 or 2 bhp there.
so the question is why is it down on power compared to the first power runs? compression and cylinder leak tests answer that, no3 is way down on compression, i know the valve seats are perfect, so somewhere on the line its got to of broken a ring. Still its done what i needed to do and thats test the dyno. ive already pulled it off and started making the adapter plate i need to fit the V8 rover engine. dyno dog will return.....
graph above, best to worst with broken ring, graph likes a bit spikey a lot of that is because power is actually low so small changes look big, but also because the half A4 size portrate shape, one below is same graph but in full A4 size and looks a lot better
one thing i spotted from this was just what difference oil temp could make, most of us are used to rolling roads and getting the coolant up to temp, but oil?
to get the engine properly upto temp i was holding it around 2700rpm under a light load, raising oil temp from 55 degrees to 75 so not exactly boiling, was lifting power 2bhp, so clearly if your not watching oil temp you could think your tuning is making power rise, but it may just be the oils hotter
Ssssssh ! - don't give all the dyno secrets away, some people pay good money for those couple of hp LOL!
so whats the spec of the rover engine?
its from a rover P6, but was originally an injected SD1 vitesse engine its still 3.5 9.75cr, lightly ported 4.6 heads, crower fast road cam, twin su's with poppet valves removed from throttle butterflies, ported intake, standard cast iron 4in1 exhaust manifolds. client is taking it back to America so i needs to look standard on the outside.
in the sd1 it would of made 190bhp, but P6 intake and exhaust would of dragged that down to about 150. anything over 200 will be good
doesn't the 4.6 head increase the cr?
no not if you swap from steel to composite head gaskets.
whats that about ?
because of the age of it, if it looks standard he will have no problem registering for use in the States, but if it looks like its been modified then its got to go through something along the lines of an SVA
Nice work and well done, there’s not many who would of took on a project of this calibre.
Bit of useless info and the closest claim to fame I've had in my 4 decades here on earth...... I fitted the very last brand new factory V8 to an SD1.
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V8 is on the dyno, despite being very carefull to break in the cam as instructed by the suppliers, ive got an issue in that not all the cam followers are rotating, i suspect its because the valve spring specified to go with the (mild) cam are to my mind insanely stiff, the springs are giving what the cams supplier specified but i cannot fathom why we need 230lb seat pressure and 300lb on the nose..
with guesstimated timing and jetting i did a couple of quick pulls just to a couple of thousand revs and saw 218lbft @2600 rpm, which is pretty dammed strong, as standard this engine was only rated at 210lb on more effiecent inlet and exhaust system
Last edited by Graham; 17-03-2021 at 20:17.
bit of a jump back in times, but for anyone interested heres our latest video on the build process of the dyno https://www.youtube.com/watch?v=hvYnAiMeayU
the rover engine is done, i switched out the cam for a newman Ph1, so very mild, my customer is a cruiser not a racer, there really was no point it fitting a lot of cam, it idled better than standard! it would tick over @470rpm and you couldnt tell it was running, and you could load it up with full throttle at 1000rpm! i also discovered just how restrictive the standard rover airbox assembly is, an early power run showed only 130bhp @5000rpm, wideband was showing 14.7 at full throttle. without doubt some cylinders were richer and some a lot leaner as fuel distribution isnt great. even if that AFR was correct for all cylinders there was power to be had, i put the standard filter assembly on it and the AFR was now 11.8 and power up 20 to 150bhp.
in the final tune i finished up with 208lbft @3100 and 172@ 5000, it might of held the power on a little longer but my customer is never going to rev it that hard and by now i was getting worried i would be wearing the thing out as that was the 118th run i had recorded, plus all the warm ups and breaking two different cams in so i called it a day there.
172 bhp even a a lowly 5,000 rpm isnt huge, but im happy with that, its got the mildest possible cam upgrade, a standard intake system with only a couple of internal tweeks, no raised compression and a pair of mild heads, and standard exhaust manifolds, i also doubt any P6 engine had 155bhp rover claimed on the later ones, given that they also claimed 155bhp for it when it was in the SD1, which had improved heads and vastly improved exhaust manifolding and system
I don't know why - but you don't look like what I imagined you would LOL!
Glad to see the beast is up and running - a useful tool, that makes money as well, so can't be bad!
i always think that when i see someone i have only known over the phone or internet
On the topic of dyno's...found this quite amusing.
Old Ford V8 where they fitted LS heads, and added boost.
Interesting to note what looks to be an overhead crane in the room. Plus it also highlights some safety aspects for such a cell.
https://www.youtube.com/watch?v=Qjbk1hZkgB8
9.85 @ 145mph202mph standing mile
https://www.youtube.com/watch?v=Ss_c7fML3rw
james, ( my son in law) has uploaded another video
https://www.youtube.com/watch?v=lYePLySIOv8
I love this project. Now I'm working on DIY roller dyno but in future I would like to have an engine dyno like yours. Thanks for all the info on your build
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