Mi16 Rebuild - Ideal Spec?

[pp205 17]

Hi, I am looking to rebuild a 1.9 Mi16 engine with a view to eventually running throttle bodies and new engine management in my 205.

 

What is the best/ideal specification to build the engine to in terms of head and cams, etc so I get great performance but without destroying the engine?

 

Any advice will be greatly appreciated!

 

Thanks Simon

[DrSarty 90 1 Cars]

Simon,

 

I think the reason you have many views but no replies in this topic is that this is such a subjective question. What does 'best' mean?

 

There are many, many great engines on this forum, some standard rebuilt Mi's (we're only talking 16v here BTW) and some lairy N/A and forced induction jobbies and they each have their pro's and con's.

 

You have not specified what you're using the engine/car for. You haven't stated budget, your own skills and whether the car will be used on the road. Hence I feel no replies suited to your original question.

 

But also 'best' is not going to get you much of an answer. I suggest you look through the forum members' project car topic and see which route you fancy going down, 'to charge or not to charge' perhaps being your first question once you've specified what you want the car for and budget/timescale restrictions.

 

To get you started, my sig shows what can be done by a cheap skate with parts pretty much 'off the shelf' keeping cost and complexity down. Should be good for a very torquey but very road useable circa 180bhp motor, which was my plan. Big CC is a route chosen by a few on here, with some going further but with more cost of course.

 

What's your plan? (After you've read through others' specs first) There are also several similar threads and people get tired of typing the same stuff (to be quite frank), but my thread http://forum.205gtidrivers.com/index.php?s...63&hl=myths here is worth checking out, as it helped me choose my route when I started.

 

DrS

Edited May 18, 2007 by DrSarty

[petert 585]

I agree with Richard, you really need to be more specific. There are two main limitations in an Mi16, the std. cast pistons and the hydraulic lifters. Using the std. pistons means you're limited to 11:1 at absolute best and the hydraulic lifters limit your rev limit to approx. 7500. So using those two items means you don't need a lot of cam timing. Don't waste your money on big bump sticks!

[Richie-Van-GTi 71 2 Cars]

Have you already got the MI16 motor or are you looking to buy one for this project? Id consider looking into the steel lumps if your looking to buy, weight difference is negligible and it means starting with a newer engine and possibly a stronger base for future mods. You also state eventually running bodies and managament, this I fear may limit you on initial build with regards to cams and for the best performance may mean better cams when the bodies arrive to keep to one lot of mapping costs.

Im doing exactly the same as the Dr, being a cheap skate and building 'off the shelf' where possible. Had a lot of advice from people on here, in particular Petert who even rang me from Australia to discuss options and some specifics to make sure I run the correct cam profile for the engine build etc. I started by saying right I have such and such an engine, I have a target of X bhp what are my options.

[DrSarty 90 1 Cars]

Could you explain the restriction imposed by the original cast pistons please Pete? Sorry if it's been answered before but I'm interested. To me, a piston is a fairly simple item.....

 

[taffycrook 2]

I was asked a similar question and my reply was as close to std as possible.

You can spend a lot of money with little gain, the head can flow enough for most road applications. So you need spen little there.

I would build a std motor with cams and vernier pulleys.

If you use a hyd profile you should get away with the std ECU untill you fit the bodies.

I have used this set up with std inlet and exh set ups to get circa 180 bhp. On TB's this should get close to 195-200.

[pp205 17]

Thanks to everyone for their advice, I see my post was vague to say the least!

 

I am in a slightly different situation now as the bottom end has gone on my 1.9 8v engine that is currently sat in the car. Now while I don't currently use the car everyday I do need to have a car that works so I really need to get on and get the Mi into the car.

 

I have a 1.9 Mi alloy lump sat in the garage. I don't really know anything about the history of the lump but I have told that it has had a bottom end rebuild. Now before it is put into the engine bay it will be stripped and rebuilt anyway as there is no point in putting it in only to have to take it out soon after and repaired! I will be using the 1.6 gearbox that is currently attached to the dead engine but am slightly worried by the higher revs at motorway speeds. I also have the 405 loom and ecu which has a superchip.

 

My plans for 'big' power will have to be put on hold but I am sure it will be quick enough for me until then!

 

My current dilema is which exhaust manifold to use. After reading many threads on here I cannot decide if I should use a re-angled manifold, the more expensive option of a 4-2-1 manifold or the re-angled plate. In my current monetry situation I am swaying towards the re-angled manifold but have read contrasting views as to whether it will crack or not. Opinions are welcome!

 

I also am surprised of the limited range of people who sell a silicone hose set for the Mi engine. I am sure Samco used to sell one but after contacting them I was told they don't, the same applying to SFS. The two choices that I can see are the 8 piece Spoox set at £150 in a variety of colours or the 10 piece Bakers Bushes set, in blue or black, at £165. Again, opinions are welcome!

 

Any other advice that anyone may have please let me know as I find this site to be the best place to find out anything for the 205!

 

Thanks Simon

[Alastairh 47]

Ok this is the start of the 2007 205gtidrivers phase!

 

For cheap power in a 205, GTI6 anyday

 

You can drop in a 60k £400 motor that won't need rebuilding, do the loom in an afternoon. They're not hard to do, just like an Mi, and if you do a search theres a few threads on whats what. Also there quicker than the the equivilent spec Mi16, just ask Ben Allen

 

If you throw on a belt, S16 tensioners and pump, new mi clutch run a Mi box (all do able for under £600 with the price of the engine). And your mi is going to cost you what £300 for an ebay special, then rebuild the 120 miler so thats another £400 of parts, but when it comes to the track you have to drive like a women around certain corners

 

Also you ditch AFM's

 

Since converting mine 2 weeks ago, i've done 1000 miles, and had owners of tubo technics 205's, 1.9 and 2.0 mi's come for a passenger ride spin and agreed that the money to grin is great value, which is what a 205 is all about, cheap fun

 

Alastair

Edited June 10, 2007 by Alastairh

[VisaGTi16v 1]

Two points. I have a GTi6 engine as ive got Xsara VTS as a road car and I agree, nice and torquey, would love to try one in a 205(/Visa) but I also think theres too much bad hype about the Mi16s blowing up on track. Get a decent baffled sump, not a xu10 single baffle door and you should be fine. Ive had 4 years out of mine, nearly 30 sprints, trackday etc and I run on slicks so far higher cornering loads than road tyres. It had done 90k when I got it as well so god knows how its been treated

 

My Xsara is probably about to be written off though due to some idiot reversing into it so I may end up buying a 205 with a blown engine off ebay and merging the two

[VisaGTi16v 1]

Google for a program called gearcalc, go and measure your tyre diameter (dont just put in the numbers ie 185/60/15 or whatever as that gives a too high reading), then put in the 1.6 ratios and you can get an idea of revs at certain speeds to see if you think you could cope with a 1.6

 

In my Visa 4k is 70, 5k is 90 etc so it is a bit painful but then its on 13's, no interior etc, depends how high you want to cruise really

[petert 585]

Get a decent baffled sump, not a xu10 single baffle door and you should be fine.

 

Interesting advice given the number of GTi6 engines that have spun a bearing. The next step after a trap door sump and windage tray is a dry sump.

[DrSarty 90 1 Cars]

Interesting advice given the number of GTi6 engines that have spun a bearing. The next step after a trap door sump and windage tray is a dry sump.

 

Just confused at your tone of delivery there Pete. Do you mean 'not many' GTi6's have spun a bearing OR many have?

 

I ask this because I am currently fitting the sump spacer between my block and XU10 (I guess standard GTi6) baffled sump and the (again standard) windage tray, and am obviously concerned that - if I take your comment the negative way i.e. many GTi6's have spun bearings - I should still be a little bit worried about oil starvation issues.

 

Should I be?

 

Rich

Edited June 11, 2007 by DrSarty

[Baz 421]

I took it to mean that after Darren's (VisaGTi16v) comment about 'proper' baffled sump's, as opposed to trap door '6 types, that Peter means that not many have/do spin shells, so therefore in his opinion the trap door sump and windage tray is the way to go, and the step up from that is full bore dry sump setup. ?

[Mandic 0]

Correct!

 

Cheers

 

Ziga

[VisaGTi16v 1]

Well yes I meant from my very limited knowledge that a more extreme baffling set up must in theory work better than a single trap door set up in a Mi16. I know its the engines weakness as ive read of so many dying. I have just been lucky probably and as I said, I would love to try my Xsaras engine in a 205 as it has a damm sight more torque than my Mi16 equipped Visa and should be a lot more reliable in standard form (as long as you change the belt and tensioners!)

[Malachy 0]

Just confused at your tone of delivery there Pete. Do you mean 'not many' GTi6's have spun a bearing OR many have?

the 2 main killers of gti6 engines are cambelt failure and spinning a bearing.

its not increadably common as they are quite rel;iable lumps but it is one of the most common failures

 

regards

Andy

[VisaGTi16v 1]

When i got my Xsara it had a receipt for a cambelt change. When the cover was taken off due to a bit of a rumbling noise 10k after this new cambelt, the garage was shocked it hadnt blown up as their was so much slack in the belt due to a worn tensioner which obviously hadnt been replaced back when the belt was done!

[petert 585]

The point that needs to be made is that the XU10 setup does a much better job at controlling the oil than the static, combined baffle/windage tray options that have been available for a long time. The XU10 setup comprises of more than just a single wall. A second wall is created by a baffle which is bolted to the pump. A windage tray separates the crank from the oil.

 

All the track/race cars I know of over here that are running wet sump have converted to the XU10 setup, most of them with my extended pickup option. None of them have spun a bearing since.