406 replies to this topic

[l_jonez]

Yeah no damage etc just a brown trouser moment.

Ended up leaving the engine as it is but rolling the whole subframe forward.

I'm about 250 miles into the initial 500 running in then a few more careful miles before a session on the rollers

[l_jonez]

just for reference with the 1.3 box fitted now 60mph in 5th comes @ 3k rpm and 70 @roughly 3.8k rpm

[l_jonez]

Now that it's getting cold I've found the 82deg stat ( was already in engine) is stopping the engine warning up properly and any thing above 40mph the temps plummet. Looks like 86 or 88deg is required.... Other than that every thing is running fine :)

[ibrooks]

The temp of the stat is irrelevant - if the engine isn't getting warm then the stat is dud.

Think about it - an 82 degree stat closes at or around 82 degrees. When the engine gets above 82 degrees it opens and allows the coolant to flow through the radiator to cool down. When the engine (or at least it's coolant) gets back down to 82 degrees the stat closes and the coolant should only be flowing around the engine again - not the radiator. An 82 degree stat WILL keep an engine at or above 82 degrees unless it's not closing. The only way for it to overcool is if coolant is still flowing past the stat - or if you've got a bypass that's flowing enough coolant to dump more heat than the engine is making i.e. there is some cooling capacity that the stat isn't controlling (in which case mucking around with the temp of the stat is going to make stuff all difference).

Iain

Edited by ibrooks, 13 January 2013 - 07:07 PM.

[l_jonez]

Stat is definitely working, I have a digital gauge plugged into the original micra sender and you can watch the temps rise and lower as the stat opens/closes.

for years it was common to have a 88 degree stat fitted in winter and a 82 degree stat in summer. 6 degrees don't sound much but it makes a big difference

[ibrooks]

A stat can partially fail and not close completely whilst still opening and closing enough to affect coolant flow (or there could be something jammed in it stopping it from closing past a certain point).

Is the reading from your temp gauge reliable? There are a good number of gauges out there that are wildly innacurate - OK for an indication of what's going on but you need to be aware of that if you are going to try and use them beyond that. Are you seeing REAL engine temps below 82 degrees and it's not just the gauge that's saying that. Do you have any other indication that the engine is cooler than it should be?

Is the temp sender near the stat? it's not unusual to see a fairly wide range of temps depending on where you measure in the system.

What is the "correct" stat for the Micra engine? Nissan no doubt put a bit of thought into the optimal running temperature of their engine and it's a bit arrogant to suggest that we know "better". If the 82 degree stat is the incorrect one then fair enough whip it out and fit the correct one but there should then be no reason to change it come the warmer weather.

Iain

[l_jonez]

Both the gauges read correctly, The correct stat is 88 according to the Haynes manual and auto data.

[ibrooks]

Then stick an 88 in there and leave it alone - if you start having temp issues come the summer (assuming we get one this year instead of the monsoon we've had for the last couple of years) then look at the cooling capacity rather than trying to bodge it by sticking a lower stat back in.

Iain

[l_jonez]

Engine is finally run in got nice torquey power but I feel it can be better. Next step is to get it on the rollers to see how well the carbs perform.

Plus I've already started collecting parts for its next upgrade - ITB's and mappable fueling - cams - lighted flywheel but I'm in no rush these will happen slowly as and when they come up cheap.

[fuzzy-hair-man]

You've got Corsa pistons in this right? http://www.micra.org...e-2#post-553594

What compression ratio did that give you? Any reason you didn't use CG10 pistons? you were looking at going a turbo route, I imagine this has this changed (maybe not ) if so why?

Edited by fuzzy-hair-man, 03 March 2013 - 09:35 PM.

[l_jonez]

Probably around 12:1 I did work it out but don't have the calculations to hand.

I had some second hand 1.0 pistons but they where not usable due to a worn block. I tried to get oversize pistons but even from Nissan there was a months wait for them to be shipped and at a cost of £375 just for the pistons I decided to go down the corsa route as it gives better power for the same money ( actually a bit cheaper).

Yeah the turbo idea has been scrapped now, mainly due to the lack of space.

[fuzzy-hair-man]

Thanks...

I found this thread:
http://www.micra.org...-options.53791/
If I remember correctly the CG10 pistons give around the same 12:1 CR right? is it more CCs that give the increased power or as the last poster says the corsa pistons may support further mods better...

I'm getting my inlet manifold made up with the 4EFTE/Corolla manifold you were going to use towards the start of your build, it looks like a goer but not all that simple I'm afraid we had to cut a fair bit of length out of the toyota manifold to get any clearance on the firewall which means it doesn't match up as well as I first though it would... it's getting there though.

In hindsight the best way seems (bit late for mine) to make multiple cuts, 1 to join to the Micra, and another one or 2 to shorten up the toyota manifold.

Edited by fuzzy-hair-man, 08 March 2013 - 11:07 AM.

[l_jonez]

1.0 pistons give 11:1

It's a combination of increased cc's and higher compression ratio that gives better power/torque. Yeah the corsa pistons are a stronger design so will be better for further mods.

Funnly enough I was looking at the manifold last night. I'll be completing it at some time bit that will be for a different project.

[l_jonez]

For fuzzy-hair-man, not sure if this helps you at all but I had my crabs off today so placed the Toyota manifold on place.

Ignore the micra manifold as its adopted for carbs but when I cut my spare one it will be slightly shorter and straight rather than the upward angle allowing 4 small sections of alloy tube to be placed between both manifolds aligning all the runners.

[fuzzy-hair-man]

Thanks L_jones

Yeah not sure, I used your original pictures as a bit of a guide cutting near the breather on the runner for no 4 piston but I cut on a bit of an angle to lift the toyota manifold up to help clear... (runner's swooped down slightly then curved up and around).
The manifold I got was a 5EFHE manifold which looks very similar (almost identical) http://board.tercelo...table&tid=23606 but I think the subtle differences might be what's caused mine to be more difficult, I don't know which Corolla yours came from but the 4EFTE is a special import motor so the 5efte was as close as I could reasonably get.
I'm tempted to pay the extra for the guy who's welding it to make me a custom manifold.
Its strange I'm not finding very much room around my engine at all (duh it's a mini conversion huh!?) but I don't know if mine is positioned slightly differently to yours, dutch mini's or rids for instance I can't fit the little swift alternator at the front of the motor without a fair bit of cutting and spacing out the grill. Mine's not a flipfront so that might be part of it but still...

PS I think I'll start a build thread soon, it's probably high time.