1905Cc Mi16 Solid Lifter Conversion - Any Experiences?

[Alan_M 66 1 Cars]

I'm seriously considering converting my Mi16 to solid lifters to negate the oil surge. Just wondering if anyone on here has done it, and would like to pass on their experiences?

 

This will be for a occasional road/mostly track car. Yes, I could go GTi6 head but I can't help thinking it would diminish the '1.9 Mi feel'. It's still an idea, but I'm looking at converting the hydraulic lifters and making custom shims (I have a friendly, skilled machinist to hand and stock of silver steel). Potentially stage 2 solid grinds maybe?

 

Advice/tips welcome!

[kyepan 291]

only to say i did briefly consider this a couple of months ago, then realised i had not pocketed the pistons during the rebuild, or had enough compression to make it worth it cam's wise.

 

I'm assuming you have an xu10 sump, extended pickup, 2 bar spring, 26 tooth sprocket etc, and keep it brim full of oil when tracking.

 

 

I've not seen any surge even during long hard left handers since the rebuild using this setup.. not wanting to open a can of worms, as i'm sure the lifters will resolve it, even if cam choice is a secondary thing.

 

Could you afford a refresh with a slightly decked block, pocketed pistons, and teensy bit thinner gasket? if so i'd love to see what it can do.

Edited February 27, 2013 by kyepan

[welshpug 1,657]

I think you have misread what you are seeing Justin, what you have seen is a lack of oil pressure drop from the prevention of oil starvation, not the prevention of oil surge.

 

/pedant

 

 

Messing around with the lifters will not reduce oil surge one single bit, however it will lower the consumption of oil by the head, leading to more oil in the sump.

 

Which in turn leads to lower chances of oil starvation, which is caused by oil surge, and possibly the consumption and poor return of oil from the head leading to lower oil levels.

 

 

The only true way to prevent oil surge is to not have a sump full of oil, i.e run a dry sump.

[kyepan 291]

it's ok mei, i know i was a little off point.

 

the only way to prevent surge, is like you say loose the sump, but surge is fine, so long as it is contained and you do not have starvation.

 

I'm still a little confused, as the volume of oil in the lifters can't be more than about 20cc, granted there are 32 little oil ways, and the oil grooves in the head and lifter. But still, even if you were to replace the lifters with solid, the oil would still be pressurized into lubricating the lifter bores.

 

I'm trying to say that i think lifter bore clearance might be a factor, at minimising oil use by the head.

[welshpug 1,657]

I do believe that in doing a solid lifter conversion you install a restrictor into the pressurised oil feed to the cylinder head.

[petert 586]

Oil surge in these engines is such a bastard. I have a friend running a hydraulic 1905cc engine, with an identical setup to my solid 1998cc engine. He got bad surge last round, destroying the rod bearings and I lived to fight another day. So we're throwing everything at it, in stages. First plan is to build a better sump using an XU9 8V A/C sump. Monitor that, then fit solid cams and convert the lifters and fit oil returns from the head.

 

To convert the hydraulic lifter, make a single piece hollowed out piston, that replaces the two piece hydraulic piston. No shims are necessary, as clearance can be controlled by the length of the piston. The lifter will still fill with oil. To enable oil to drain, grind a slot down the side of the piston.

 

To make like easy, turn up some dummy mild steel solid pistons to begin with, in order to get the clearances within a suitable range.

 

And remove non-return valves and fit restrictors.

Edited February 27, 2013 by petert

[petert 586]

I forgot to mention we are both running 3 quart accumulators, which feed directly into the oil gallery.

Edited February 27, 2013 by petert

[kyepan 291]

 

To convert the hydraulic lifter, make a single piece hollowed out piston, that replaces the two piece hydraulic piston. No shims are necessary, as clearance can be controlled by the length of the piston. The lifter will still fill with oil. To enable oil to drain, grind a slot down the side of the piston.

 

How would this appreciably reduce head oil consumption though? as you've still got oil going through all the lifters and out again? Do the cat-cams lifters work the same way, or are they just solid units, and the oil splays onto the lifer bores?

 

 

 

I do believe that in doing a solid lifter conversion you install a restrictor into the pressurised oil feed to the cylinder head.

as in under the head, on the oil way up from the block?

Edited February 27, 2013 by kyepan

[Alan_M 66 1 Cars]

 

only to say i did briefly consider this a couple of months ago, then realised i had not pocketed the pistons during the rebuild, or had enough compression to make it worth it cam's wise.

I'm assuming you have an xu10 sump, extended pickup, 2 bar spring, 26 tooth sprocket etc, and keep it brim full of oil when tracking.


I've not seen any surge even during long hard left handers since the rebuild using this setup.. not wanting to open a can of worms, as i'm sure the lifters will resolve it, even if cam choice is a secondary thing.

Could you afford a refresh with a slightly decked block, pocketed pistons, and teensy bit thinner gasket? if so i'd love to see what it can do.

It's all Anthonys fault! I was going to build a mega 2.2 but after a chat with the wise-one, it seems I have a love for the 1.9 Mi16 and it's eagerness to be thrashed. My only fear was the surge and drop in pressure. A lap of the 'ring is like an 80's school disco in my 205 (I have a large light where the centre vent is next to my mechanical gauge). My plan is to refresh the engine, even though I rebuilt it only about 8 years ago and covered 30k since. Yep, deck the block, pocket pistons, solid lifter conversion etc.

Oil surge in these engines is such a bastard. I have a friend running a hydraulic 1905cc engine, with an identical setup to my solid 1998cc engine. He got bad surge last round, destroying the rod bearings and I lived to fight another day. So we're throwing everything at it, in stages. First plan is to build a better sump using an XU9 8V A/C sump. Monitor that, then fit solid cams and convert the lifters and fit oil returns from the head.

To convert the hydraulic lifter, make a single piece hollowed out piston, that replaces the two piece hydraulic piston. No shims are necessary, as clearance can be controlled by the length of the piston. The lifter will still fill with oil. To enable oil to drain, grind a slot down the side of the piston.

To make like easy, turn up some dummy mild steel solid pistons to begin with, in order to get the clearances within a suitable range.

And remove non-return valves and fit restrictors.

I was going to go by the diagram below and knock-up something similar.


I'd like to keep costs down, but other threads seem to suggest I may well need to new springs/retainers/spring-shims (http://forum.205gtidrivers.com/index.php?showtopic=143344&hl=lifters&page=3). Edited February 27, 2013 by Alan_M

[petert 586]

You can certainly do this job a lot cheaper than you think. For example, the silver steel stock we get here has an excellent surface finish and is a perfect fit into the bucket. Thus minimal machining is required. In regards to cams, I'm using these profiles in the 1905cc engine which fit easily on the standard cams as a regrind. Any reduction in base circle diameter is taken up by the length of the new piston.

 

INLET
277 deg @ 0.010"
240 deg @ 0.050"
0.368" lift

EXHAUST
266 deg @ 0.010"
233 deg @ 0.050"
0.375" lift

 

You can use standard springs if they're shimmed correctly. Otherwise, use the Catcam single PAC-S10011 and re-shim if your standard springs don't pull up.

 

If using a standard head gasket, you "possibly" won't need to pocket the pistons as you can run the clearances a bit tighter with solid cams. I'd fit the Cometic 0.7mm gasket and do the job properly however, for optimum results.

 

The Catcam lifter/bucket doesn't have any internals, other than a spigot, thus can't retain any oil. I use a Kawasaki bucket which is completely empty. The benefit of these two is weight reduction, as no oil is in the bucket. Restricting oil by replacing the one way valves just helps to minimise the amount of oil being delivered to the head. There is still sufficient to oil the cams and run the spray bars, but not enough to operate a hydraulic lifter. Thus oil will still pool around the exhaust cam/valves and ideally needs to be drained away with external drains, dry sump scavenge pump etc.

[petert 586]

We've been doing some more work on this. The rod bearings had just started to fail. Luckily we caught it in time before damage was done to the crank. Adrian was running the XU10 sump and the special oil pump baffle as shown. The new sump wall is significantly higher as you can see in the picture of a similar 8V A/C sump. The surge was particularly bad on a tight right hander, so I'm hoping the higher wall will help the situation. With new bearings fitted, we'll give it another thrashing on Sunday and see what happens.

 

Then after that it's solid lifter time and external returns (which must be a good thing anyway).

Edited March 6, 2013 by petert

[DanteICE 72]

Out of interest are you running an oil cooler of any sort?

[pip470 61]

I used solid lifters made for the vauxhaul 20xe engine and never fitted a re-stricter to the oil. That was for a gti-6 engine though. So, all my information is probably no use.

[petert 586]

13 row cooler.

[DanteICE 72]

13 row cooler.

On both or the one with surge?

[petert 586]

On both, as said, they were identical, other than being iron block/solid and alloy block/hydraulic.

[DanteICE 72]

Oh sorry, forgot about that. Really interested with how this goes.

 

Geoff

[petert 586]

A successful day with the alloy block. Adrian fitted the new sump, new rod bearings and new oil. He also fitted a capillary oil pressure gauge. He disconnected the accumulator. Adrian reports that the 35psi idiot light didn't flash all day. He recorded the runs with a GoPro, with the gauge in view. So it will be interesting to see the footage.

[petert 586]

I can report that the oil pressure doesn't drop below 40 psi in video, 60 psi max. Hope to have the video up soon. Results of the round can be found here:

 

http://racing.natsoft.com.au/results/

Circuit Racing

10/3/2013 Club Lotus Australia - 2013 CSCA Supersprint Round 1

Click on "SS"

 

It was Adrian's 3rd fastest time ever, so he wasn't just doodling around.

Edited March 15, 2013 by petert

[wicked 103 3 Cars]

What spec oil do you use?

[petert 586]

Mobil1 5w-50 this time, last time not sure.

[JeffR 51]

Peter, what was the reason Adrian ran without the accumulator?

[camgti 56]

Maybe to not have to use one? Only reason I can think of..

 

Cam

[petert 586]

Just wanted to test it without, so it waasn't masking any problems.

[petert 586]

Here's the first run. You can see the oil pressure gauge sit on 60psi (2 o'clock) most of the time. However, exiting "The Fishhook", turn 8, a sharp left hander, you can see it drop to 40psi (10 o'clock) momentarily.