Jason Moyle Racing
General Category => ROLLING ROAD & ENGINE DYNO RESULTS => Topic started by: Markg on February 14, 2013, 09:16:21 am
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Hi, I'm new to the forum, my mate Tim Watson has just had his 16v head done with you and is very happy with the results, so was i that thing a little rocket.
I have a mk1 gti dx which i have been doing a few mods on lately: light diy port and polish, polished valve dishes, 3 angle valve seats, ashley 4 branch, 16v throttle body, 16 v WUR, piper 270 cam, vernier pulley, minimal head skim. I have just a few questions with regards to set up, the car is just for enthusiatic road use on those infrequent sunny days and general pottering:
1. Is there benefit from slight timing alterations or just a trade off between top/bottom end (currently bang on tdc)
2. What is the optimal ignition timing for performance/ smooth running with these mods ( currently 6 degrees btdc)
3. I have read a lot of controversial lit around air box drilling/mods, in your experience are there any quantified gains from some work to e airbox? Currently standards with a k&n panel filter
Interested to hear anyones thoughts
Mark
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Hi Mark.
Welcome along
With ignition timing, I'd suggest trying adding advance just until it pinks then back it off slightly. You should get a wee bit more if the head has only had a little skim. There is no ideal setting for a particular set of mods, you just need to experiment.
For the airbox, a few little holes really won't achieve anything. If you open out the outer side & custom fab a decent cold air feed you might gain 1 or 2hp & beefier induction note (I did Tims airbox)
Cam timing I always used to set to give equal lift on overlap at TDC as a starting point. Advancing it a degree or 2 from there would stoke up the mid range. Ideally you want it on a dyno to perfect that & also tweak the fuelling via the 16v WUR. My 8v never ever benefitted from retarded cam timing
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Thanks Chris thats some good info, I've got a session on the rollers booked at Clive Atthowe as am over in Norwich so will have a play there, how can you tweak the WUR? Is there an adjuster somewhere?
I might have a play with the air box :)
I have the stardard exhaust from manifold back, do younthink this is too restrictive, i dont want to much noise and am trying to keep the look standard?
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Hi Mark,
Welcome to the forum :)
There most certainly is an adjuster on the 16v WUR, if you remove it from the alloy mounting on the block you will see a brass cap on the back. What you need to do is clamp it in a vice or even better in a pillar drill and very carefully drill a hole in the centre of it.....I usually use a 7 or 8mm drill (whichever is sharpest at the time) Behind this brass cap you will find a screw that you can adjust with an allen key to alter the control pressure.
The exact setting will be dependant on the tune of engine and can be a little trial and error on the rollers. With the air metering head that will have been standard on your car you will typically find that the fuelling will start to run lean at the top end....hence the need for adjusting it slightly, but adjust too much and it will be too rich elsewhere!!
The Slick50 boys of old use to fit 1600 air metering heads as the cone in these is significantly different to the 1800 items and provides a better fueling profile for modified cars, however these ran a far higher level of tune than yours and I'm not certain what benefit it would give for you if any at all! I have one of these fitted in mine but I am running a 1900 bottom end with a big valve head, 11.5:1 CR and 300deg cam but it certainly leveled out my fuelling ;D
Here's the two air metering heads side by side....the bigger dia one is the 1600 one...
(http://i149.photobucket.com/albums/s70/mitlom/Road%20Legal%20Track%20car/IMG-20120606-00082.jpg)
And here is some AFR data from dyno runs with the two different air metering heads to show the effect on fuelling profile and also the effect of control pressure :)
(http://i149.photobucket.com/albums/s70/mitlom/Road%20Legal%20Track%20car/AFRvsRPM.jpg)
Hope this gives you a little food for thought.
Tim
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Cheers tim, i had read about the 1600 metering heads providing better fuelling, and thanks for the tip on the WUR adjustment,i shall prep that For the rollers. The 16v WUR was a bit of a fluke really as i had fuelling issues on my first run prior to the mods, I had 5 bar control pressure! Popped on the 16v WUR and control pressure is know around 3.75 when warm and drops with the vacuum advance as you throttle hard so will be interesting to see if this will suffice.
What sort of power are you getting out out yours Tim I bet its a bit of a rocket :)
On another subject I have just done an oil and filter change, started and have low oil pressure and oil is not getting around the engine, tried giving a little rev and no joy so switch off sharpish, i thought is may have been a dodgy filter so i put some fresh in the old one and started her up and still the same issue, i have never had this on any car, possible hydraulic lock? Or feed pipe blocked??? Typical!
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Hi Mark,
Yeah mine goes pretty well ;) There's a build thread on here http://jasonmoyleracing.createaforum.com/customer-cars/tim-moll's-red-mk1-trackcar/ It's producing 155bhp so a fair bit of fun ;D
I don't tend to bother with the vacuum connection on the 16v WUR TBH I just leave the outlets on the WUR open to atmosphere as with them connected I have found previously it overfuels at top end!
With regards to the oil pressure problem I have had this before with an old engine.....but only when I have drained and left engine for a little while before filling it up! I'm not sure what causes this but suspect it's either a worn pump or worn main bearings but not certain....what I do know is whenever I build a new engine I fill the pump with grease and this prevents this issue on initial startup...however this doesn't help you much unless you feel like whipping the sump off!
I actually made a tool up that attaches to an electric drill, you pull the dizzy out and drop this in the hole where dizzy normally lives and it slips over the drive on the oil pump and a quick spin of the drill and hey presto......the other solution which might get it sorted is whip the plugs out and disconnect the DIS plug to the dizzy and crank away until you get pressure, ideally do this while jumping from another car so you have plenty of cranking speed and don't flatten the battery ;)
(http://i149.photobucket.com/albums/s70/mitlom/DSC01970-1280.jpg)
(http://i149.photobucket.com/albums/s70/mitlom/DSC01973-1280.jpg)
(http://i149.photobucket.com/albums/s70/mitlom/DSC01971-1280.jpg)
Hope this helps a little.
Tim
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Nice tool ;) thanks again tim, i might whip of the sump to check pick up gauze anyhow I've heard these can clog sometimes, I'm hoping its a simple fix, the engine was still hot at this point and no previous issues so should be mechanically sound, i might even pinch your tool idea!
155bhp too, wow thats awesome, mine was 102 at flywheel pre works, we will see how my handy work bears up
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Mark if you are struggling let me know and I can always stick the tool in the post to you if you need to borrow it.
Cheers,
Tim
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And this is why this place is so great! Welcome Markg, get some pics up buddy 8)
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Cheers Tim, thats very helpfull, i will have a play today, i will get some pics up later, i have baby duties to attend to :)
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Hi Mark
Welcome aboard! ;D
Yeah Tim appears happy with his 16v head...goes ok apparently.. 8)
Ive found a 4hp gain back to back on the rollers with a modded air box.
Ignition timing can be usefully increased to 8 degrees on idle.
Cam timing needs checking via the lift @ tdc method to ensure it's right...front pulleys can be out so use the flywheel as a guide, but the true tdc needs to be found off a piston through a plug hole with a dial gauge. Most cams run better with some advance...more lift at tic on the inlet than the exhaust...15 thou is a good starting point measured off the cam buckets.
I've done road spec 1800's with a 268 cam and mild head work making 108 at the wheels..
132 at the flywheel...so you don't need mega specs for road fun.
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Great stuff, I confirmed tdc from the piston during the build and then the cam as you say using the disk on the crank. Interesting on the air box, i will get something done, ae there any picturesnof modded boxes that anyone has? If i got anywhere near 130 flywheel i would be ecstatic! Thanks for the info:)
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Mine is modded to the max...pretty much the whole of the underside is cut out, however this itself brings it's own problems as the inlet charge was VERY hot when I first had it on the rollers as it was sucking hot air in from the engine bay! For this reason I made up an aluminium heatshield that wraps underneath the whole of the airbox and up the side, at the same time I re-located the battery to behind the passenger seat and fitted a large cold air feed mounted in the grill to feed the enclosure.
(http://i149.photobucket.com/albums/s70/mitlom/Road%20Legal%20Track%20car/DSC06847.jpg)
(http://i149.photobucket.com/albums/s70/mitlom/Road%20Legal%20Track%20car/IMG-20120620-00102.jpg)
(http://i149.photobucket.com/albums/s70/mitlom/Road%20Legal%20Track%20car/IMG-20120620-00103.jpg)
(http://i149.photobucket.com/albums/s70/mitlom/Road%20Legal%20Track%20car/IMG-20120620-00101.jpg)
(http://i149.photobucket.com/albums/s70/mitlom/Road%20Legal%20Track%20car/DSC06838.jpg)
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Ah, i see what you have gone for, looks like a good job, my issue is trying to keep the standard look as it a campaign and a fairly tidy one i was thinking of an addition feed somehow hidden but dont know how i will achieve this :) car look mint Tim do you track it? Mine is purely a road goer i wouldn't mind another to track but they are getting pricey now! Maybe a mk2 for track to keep the cost down for me
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Yep this ones primarily for the track, although it is also road legal, just need to get my arse in to gear and get an MOT on it!
I've got a couple of Campaigns as well, so know what you mean about keeping ity standard looking....one of mine is fitted with a GTI Engineering RE1900 so goes well while keeping the standard appearance ;D
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Your a star Tim, the tool idea worked a treat, made one from a 1/4 extension bar, whipped the sump off and cleaned the pump strainer out to, it was a little shity, it started up with no issues,do you guys run any particular oil on these older engines, i have opted for a 15/40 mobil super 1000 mineral?
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Good stuff mate, glad to be of help 8)
A decent 15/40 sounds about right to me if it's not a freshly re-built engine.
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No its done a few miles, its lovely and quite now :) sorry for lack of pics, my iPad is making life difficult
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Rolling road tomorrow, I have drilled the WUR for adjustment as required, modded the air box and advanced the timing to 8 degrees for a starting point, first test drive today, post build and it goes really well for the subtle mods i have done, sounds good with the air box done too :) will post results soon
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Sounding good mate, looking forward to see how it turns out ;)
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Give or take, that should make 135-140hp subject to the final set up...112-114 at the wheels....let us know how you get on.
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Well back from the rollers guys and really happy with the way the car drives but the results do not read all that well, started at 101 bhp and 103 torque and is now 117 bhp and 117 torque both flywheel figures, ignition advanced to 108, cams at tdc as he wouldnt move without build data ( which i didnt do ) the fueling he wreckoned was the best compromise, i am struggling to see where we are missing out on another 20 brake jason? Standard exhaust? Miss matched gasket, compression? I did polish up he valve dishes a bit to much? What are your thoughts guys?
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I reckon it needs more fuel. Let Jason take a look
As ever its a culmination of the right bits & fine fettling that will release the power.
Edit: stratch that! I can't tell my red lines from blues! Plenty of fuel there. :-[
Exhaust will help along with a tad more cam timing advance. The main thing is the way it now drives. Must feel like a new car!
It might be an under generous dyno- especially given your before figs!
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You maybe right mate, it feels really impressive from what it was, its no rocket but is good fun :)
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It's not mega lean but not ideal at the top end, christ it's rich at 3k!...I'm presuming the blue lines are all the after runs..inc the fuel curve?
Is there any power at the wheel's figure's Mark?
Ah...if your on a std exhaust system then your 5 or so hp short right away...I gained that on my MK1 when I first had it. I recently fitted a Jetex rear silencer to replace a poor designed one...the rest of the system was fine...and gained 8hp peak and 14hp mid range at the wheels on MK2 2ltr 8v making sub 135hp.
They prob didn't want to swing the cam in case of valve to piston contact...if they knew the engine they'd know there's about 8mm clearance so that'll never be an issue...a Piper 285 wants to have around 3mm lift @ tdc.
Worth a fuel pressure check Mark...pumps go weak...and pattern pumps can be poor and inconsistent...genuine Bosch only really on these to ensure correct fuel supply as a starting point.
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High jason, power at wheels is 78@5600 ish, clutch is a little slippy now it was previously 71bhp, but that figure is well out to me the car feels as quick as my old crx that was 130 odd bhp, the red lines are from the pre work tests the blue this run. The control pressure is 3.75 when warm, the system pressure is a tad over 5 bar on a new but pattern pump, new injectors that have been volume/balance tested all within a few mls of each other at varying metering flap positions.
Whats ideal afr at the top end? 13? I have the 16v wur fitted with the vacuum pipe attached could this be an issue?
Exhaust wise what are your thoughts on the superspint 'stock look' system, Chris may know of a straigh through with just rear silencer available?
Cheers Jason, this is extemely helpful
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My first observation is how can maximum power at wheels/flywheel occur at different rpm's?
Unless I'm going mad they are directly related- so the point of max power for both should be identical?
I suppose a slipping clutch could possibly cause it- but something doesn't seem quite right.
If the car pace is on a par with a d16 crx then it sounds pretty healthy ;)
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Yes mate, i spotted that to, don't know what thats all about, why do you always spot these things when the event has finished :( i will do what i can for now and get another run and tune booked up in a bit, maybe see what someone else can achieve, Clive obviously wasn't that savvy in the end
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Hi guys, after a bit more info on the metering heads, i have in my possession a metering head with part number 0438120162 which when i google it says its from a later 1.8 dx engine it does have an electronic connection and an additional little fuel line on the actual metering head? The reason i ask is that it apears to have the larger air plate oriface? I have attached a pic. Is it the airflow plate orifice that makes these flow better or is it the internals of the metering head to? I was considering swapping the plate section over if its just this that altrs the meteringbhead performance?
One on the left
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Full pic
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Mark,
Not sure what engine that part number is for and am at work so can't check on ETKA, however that definately isn't a 1600 air metering head part number, which is 0438 120 035! To be fair these are like rocking horse poo to find unless you happen to have had a 1600 GTI and kept a load of bits.....like I happen to have done ;)
Just for clarity it is not actually the maximum flow of the air metering head, it is the profile of the cone that effects the rate at which the flap is drawn up based on air demanded by the engine, I actually sketched out profile of the 1600 head that you could use to compare to the one you've got there to see if it is anything similar if it would help?
(http://i149.photobucket.com/albums/s70/mitlom/Road%20Legal%20Track%20car/Image.jpg)
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Brilliant Tim! Loving the diagram, this one is not the same, check out the sketch it has the same top and bottom dimensions but a different profile.
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Hi Mark,
My gut feeling is it may be a bit better but it's a bit of a lottery as it's not one I have ever tried! I do have another 1600 air metering head here, but plan was to put it on the RE1900 in my road going Campaign if I have similar fueling issues on that......
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No worries Tim, like you say the profile and measurements on this one would suggest a better flow, it is somewhere in-between the two if you put the drawings together, the only issue is testing it without forking out rolling road fees every time, i was looking at treating myself to a an afr data logger, innovate do one, but mixed reviews on these :/ would be interesting fond out thou as it could open another tuning avenue with the 1600 becoming hard to find
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Just being geeky now!
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Why don't you draw the 1600 one to scale and overlay that as well...or better still I can do that on CAD tonight maybe? What we ideally want to show is the relative plate positions for the same annular area being exposed on the three different air metering heads, as it's the engines's demand for air that dictates the amount the plate is drawn upwards. This however is not that easy to do unfortunately....I'll have a think about it! :-\
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The 1600 one is in there Tim but if you mean all three together its not that clear on a sketch it gets a little busy, cad could be ideal, the angled line was a guestimate at plate position, if this cold be simulated like you suggest it would be ideal as you could do the calcs at varying plate angle positions for air flow.
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Yep can make it a lot clearer on CAD, will see if I can do something at the weekend. I only have access to AutoCAD, which is fine for 2D and simpleish 3D modeling but isn't that powerful when it comes to calculating surface areas at an angle as would be required here....but I'll see what I can do when I have some time ;)
The flap opening would then need to be converted to linear movement of the fuel metering head plunger so that we can plot lines of air flow vs plunger position as this will give us the best approximation of fueling ratio, the only gray area we may need to investigate further is whether the fuel flow is a linear relationship to the displacement of the plunger? ???
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Jason, you mentioned to check my cam lift at Tdc, what is advisable on the piper 270 cam I'm running and what is the best way to check this? I checked and marked tdc with the head off so know that is accurate, is it just a matter of no1 at tdc and then a dial reading off no 1 inlet bucket? If you get chance could u do a very brief noddy guide?
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Hi Mark...close.
Once have the true tdc lined up, no1 will both be closed for firing, so it's number 4 that both valves will be on the overlap, or "on the rock", so you'll be measuring off there.
With 1 @ tdc, rig up the dial gauge to measure off the inlet bucket of number 4 and zero it...turn the engine backwards until the gauge stops reading and note the figure down, the figure you have...e.g 100 tho...is what the lift was before you turned it back...with me? Then, turn the engine back to tdc...the dial gauge should now go back to the zero setting as an additional guide to confirm your back where you started..
Move the pointer to the exhaust valve bucket and zero in...then turn the engine forwards this time until the gauge stops reading and note the lift figure down. Whatever the two figure are, you need a starting point difference of around 10-15tho more lift on the inlet than the exhaust....on that cam the inlet should be around 105tho with the exhaust about 95.
If your within a couple of thou of those figures to start with then thats fine...remember...adding inlet lift by turning the cam if you have to will take off a similar amount from the exhaust...not always the same amount due to differences in the profile acceleration but close to it. So lets say the inlet and exhaust are both showing 100...adding 5 thou to the inlet will see the exhaust drop to 95...so giving you the 10 thou difference you need to start with...if you check it and it happens to be say 107-108 and the exhaust is 94-95 then leave it there...as long as your in that 10-15 window to start with thats fine.
Check a few times if you change any settings, even re-setting your tdc point with all the gauges off then starting over again....an 8v is simple enough but I've spent an entire day before chasing cam timing on a 16v with high valve acceleration profiles to the point of getting those greasy black spots in yr vision through focusing too long!...the wilder the cam both the more critical it gets and easier to get it wrong because the profile/lift (lift per degree) changes so quickly...plus factor in the chain taking up drive slightly different each time and the "rock" factor and you can end up tearing yr hair out!....but the satisfaction comes from finally getting it where you want it & seeing the power curve on the dyno.
There is an element of rock around both points if you wanted to be really picky, but the above will give you a good starting point...the rest is down to fine tuning on the rolling road, but anytime your within that window your just going to split hairs by moving the power band around a small amount with a road spec profile. If you find for instance the exhaust is say 10 thou or more than the inlet to start with (which is retarded cam timing) you'll find a decent improvement by going to the "more inlet" setting (advanced cam timing)....let us know how you get on.
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Jason that is absolutely perfect, and makes perfect sense, thank you for taking the time to write that out, i will be doing the check next time i can get in the garage. Will let you know how i get on.
On another subject i got a 1.8 dx block and head for a tenner off eBay the other day, bargain! So might have another project to play with over the coming months, maybe a track engine :)' I'm thinking maybe a bore out to 1900 jobba?:)
Thanks again
Mark
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That's dirt cheap for a full DX engine Mark...the head's worth more than that on it's own if it's servicable ;)
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Yr more than welcome Mark...yes indeed...let us know the outcome.
That's a bargain indeed...I paid the same for my base engine in my hillclimb car about ten years ago, the block/bore and crank was mint but I later found out why it had been removed and dumped outside a local tyre centre...the head was porious...or I should say the guy I gave it to found out!...but a bargain is a good feeling all the same.
A 1900 would be a good call. 8)
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I know Tim, its in a bit of a state externally but who cares for 10 squid, we will see what the story is inside when its in bits :) project engine number 2 just need a nice mk1 track car for it to go in now ;)
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I know Tim, its in a bit of a state externally but who cares for 10 squid, we will see what the story is inside when its in bits :) project engine number 2 just need a nice mk1 track car for it to go in now ;)
Mine is up for grabs ;)
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What the red beast Tim, you will get me in trouble, whats £'s is she going up for, not that i would get away with it at the mo :(
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Yes mate, putting it up for £3,750....need to free up some cash to try and get the new car finished!
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Bargain, very tempting but ive not finished this one yet!
Did the cam timing today, thanks again Jason, it turns out i had far to much advance on it, the first set of measurements found 3.35mm (132 thou) inlet lift at tdc. I have adjusted it and now repeatedly getting 103 thou inlet and 95 thou exhaust, as near as recommended, i will get it back together later on in the week and see how she runs
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Jason, sorry to bother you again, just to clarify am I dropping the dti onto the bucket edge or on top of the shim as i did it to the bucket edge and this could be why it was so far out :-\
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You should see a pretty noticeably difference now you've corrected the cam timing Mark ;D
Ideally you should do it on the shim in as near to vertical position as possible, so as to get accurate reading, but at the end of the day they both move together so shouldn't in theory make that much difference!
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Cheers Tim, i was just sat here thinking im having a moment, do dads get baby brain ;D, thats what I'm going for.
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LOL :D
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What he said! ::)....lol! ;D
That was certainly a bit too advanced Tim!...not a bad guess on the cam timing eh...hethum!...lol
So you have around 8 thou more inlet lift which is a start. When time permits, it maybe worth marking the pulley at that point, then advancing a touch more to say 12 thou advanced, and 15-16 advanced, and mark each step on the pulley...you then have 3 setting points to test on the rolling road the next time and see which gives the best overall spread.
Tim (Moll) found more advance than the norm works better on his set up, but his cam is a lot wilder. I can also confirm the red MK1 drives superb...a really good first step track car...user friendly...whoever snaps it up wont be dissapointed... ;)
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Not a bad guess at all :)
As recommended had another play, its such a small adjustment, i started off a bit gun ho, but have got 3 decent positions, that all fall within one increment line on the cam, about 10, 15 and 20 thou advance give or take, smaller increments proved pretty difficult with my sausage hands.
I had previously fitted the metering head from the cabby to tim on it really seem to smooth out my spluttery bottom end, just needs setting up pressure wise i was toying with getting an innovate wide band meter, but might just save my money and put towards another rolling road sess
Thank you for your help boys, looking forward to putting her back togther over the weekend and having a blast :)
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Article on your website, make the most of the information it is to read a lot longer.
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This model is good. I like it a lot. Have any information to tell?