14 replies to this topic

[Rich.]

I have been searching for a good few hours now about turbo-ing my 998. Im pretty much sold on a T2 turbo running a modified metro manifold. Although having said that, what sort of price am i looking at for the mirage manifold kit?

So, il be needing either the mirage or modded metro exhaust manifold, with the tubo bolted on. Now, what do i use for the output of the turbo to the intercooler?

Can silicone hoses handel the pressure of the output of the turbo or will i get leaks? Am i better to use steel with silicone corners? ?

Then from the intercooler im assuming its a fairly simple job to connect the cooler to the inlet of the metro turbo carb?

And the metro carb manifold just bolts stright onto the 998 block?

What about the oil? Where does the oil from the block come from to go into the tubo? And where does it return again?

Boost, how do i know what my engine can hadle? Is the T2 tubo similar to the metro turbo in that it runs around 4psi unless you fit a bleed valve and get around 7? How do i know when to stop increasing boost?

What other mods should i be doing to my engine at the same time to help it take this kind of power or give me even more? Im looking at changing the rockers to the 1:5 minisport ones aswell.

And finally, what sort of performance can i expect? What are your 998 turbos putting out? BHP, 0-60 and top speeds?

Its going to be for a daily driver car that will be used for track days and the like.

Thankyou for all the help!

Rich

[Ethel]

I have been searching for a good few hours now about turbo-ing my 998. Im pretty much sold on a T2 turbo running a modified metro manifold. Although having said that, what sort of price am i looking at for the mirage manifold kit?

It's not cheap - but then bulkhead mods can be expensive in money/time too. Turbo-Minis.co.uk would be worth an ask

So, il be needing either the mirage or modded metro exhaust manifold, with the tubo bolted on. Now, what do i use for the output of the turbo to the intercooler?

Can silicone hoses handel the pressure of the output of the turbo or will i get leaks? Am i better to use steel with silicone corners? ?

Silicone hoses will be easily up to the job, there's more pressure in your average airbed. It's expensive stuff so most people use pipes also to save cost and bulk

Then from the intercooler im assuming its a fairly simple job to connect the cooler to the inlet of the metro turbo carb?

It is if you've got a Montego/Maestro Turbo plenum, otherwise you'll have to modify a Metro one or make your own - it's actually one of the most critical parts to get right as it sets the boost fueling compensation

And the metro carb manifold just bolts stright onto the 998 block?

should do , use the turbo gasket

What about the oil? Where does the oil from the block come from to go into the tubo? And where does it return again?

oil pressure switch outlet, drains through the unused fuel pump mounting

Boost, how do i know what my engine can hadle? Is the T2 tubo similar to the metro turbo in that it runs around 4psi unless you fit a bleed valve and get around 7? How do i know when to stop increasing boost?

After it melts/blows up Boost depends on the wastegate actuator - available with various spring poundages or fooled by a bleed valve

What other mods should i be doing to my engine at the same time to help it take this kind of power or give me even more? Im looking at changing the rockers to the 1:5 minisport ones aswell.

A turbo is likely to add all the power you need, put your money into helping it stay together. Centre main strap, x pin diff, decent ignition....

And finally, what sort of performance can i expect? What are your 998 turbos putting out? BHP, 0-60 and top speeds?


Build from the bottom up and start modestly, then you can develop it as your knowledge & experience grows.

[Rich.]

Thats brilliant, you have answered alot of my questions there!

So if im going with a standard 998 engine, running a 12g295 head, a T2 on a metro manifold and metro carbs and an intercooler, with megajolt, what sort of power can i expect?

What would i need to do if i wanted to get say 120+ hp out of it whilst still keeping it a good reliable engine for every day use?

Thanks so far
Rich

[Turbo Phil]

Have you read this ? 998 Turbo conversion That's a good basic spec to start with.

[Rich.]

Yep, it was one of the first things i read. However i know hes uisng the metro turbo, but with a similar setup to above Will is only getting 80 or so bhp, would using the T2 instead be able to give me say 40 more ponies than the metro turbo?

Rich

[Turbo Phil]

The Metro T3 will be terrible for a road car, iirc Wil ran a T2 on his road car & hillclimber at one time & made 140+hp.

[Rich.]

Thats more what i wanted to hear Im going to get myself another 998 and start the build so i can still use my mini on a daily basis, might aswell rebuild it whilst im at it.

Thanks for all the help
Rich

[Wil_h]

The build linked above uses a T2 off an R5. It only produced 80bhp because I limited the boost to a sensible level as I used a standard engine that had done 70,000 miles. On an engine with better pistons this setup could easily produce 120 to 130 bhp (potentially more, but the T2 is getting to it's limits at 130 on the 998).

I'm currently building a 998 turbo for my kit car, keep your eyes peeled for a build thread on TM soon.

[GINO R32]

what sort of price am i looking at for the mirage manifold kit?

I got this kit last year £360

[Rich.]

Wow, thats expensive, il just fab my own then.

Last question, for the moment anyway Iv currently got a 998 engine in mine, but obviously i want to tubrocharge it. Now, im going to build the turbo engine up off the car, so il need to get a second engine. So whilst im swapping engines, is it worth going for the 1275 instead of another 998? What sort of figure differences would there be with the T2 between the different sized engines?

Looking at pistons, there appear to be a few available. If i went for a 1275 engine and overbored to say 1293 with +.020 pistons, what options would i have for running big amounts of boost, say 15 to 20psi just so im set for the future. I know omega sell a set through MEd engineering for £300 with a 10cc dish and +0.020, but there abit steep. What about the hepolite pistons from Minisport? Are they suibtable for forced induction of such a large pressure and does anyone know if these have a dish or are just flat tops? If there flat, do they have enough to have a decent dish machined in?

Im going to be using the car as a fast road car, so im looking 120 to 140 Brake if possible.

Thanks again
Rich

Edited by Rich., 10 April 2010 - 10:10 PM.

[Sleepy Stu]

Wow, thats expensive, il just fab my own then.

Last question, for the moment anyway Iv currently got a 998 engine in mine, but obviously i want to tubrocharge it. Now, im going to build the turbo engine up off the car, so il need to get a second engine. So whilst im swapping engines, is it worth going for the 1275 instead of another 998? What sort of figure differences would there be with the T2 between the different sized engines?

Looking at pistons, there appear to be a few available. If i went for a 1275 engine and overbored to say 1293 with +.020 pistons, what options would i have for running big amounts of boost, say 15 to 20psi just so im set for the future. I know omega sell a set through MEd engineering for £300 with a 10cc dish and +0.020, but there abit steep. What about the hepolite pistons from Minisport? Are they suibtable for forced induction of such a large pressure and does anyone know if these have a dish or are just flat tops? If there flat, do they have enough to have a decent dish machined in?

Im going to be using the car as a fast road car, so im looking 120 to 140 Brake if possible.

Thanks again
Rich

You keep saying everything is a bit expensive but there is a reason why things are expensive. If you are going to be running 15 PSI or over then do not skimp on the pistons. I wouldnt consider anything other than Omegas or Accralites for 20 PSI but as you have seen your gonna be paying £300 or over for them.

[Rich.]

For things like pistons i could justify the cost, but for a manifold set i could fab myself then i couldnt, thats all i mean by expensive. Im not tight, just dont like to waste money as many people do.

Rich

[rick.spi]

what budget have you got in mind. if your planning on building a nice new 1293 then you better open the old wallet as the build wont be as cheap as you think.

and if your building a new engine have you got any reason not to go for higher cc as its not much dearer and will reduce lag slightly. and the standard T3 is better suited than the t2 for the large bore (ie- 1275 plus) engines id say.

[Rich.]

I dont have a budgetas such, im fully aware the build will be into the thousands, but it will be an ongoing project i can just tinker with in the workshop, no rush, just do parts on it here and there.

I have herd that 1293 is about the best bore to go for on a turbo engine, and thats theres not much gain going bigger, is this wrong then?

As forTuro's, im still undecided. I origionaly diddnt want the T3 as on the 998 engine i was origionaly going to turbo it wouldnt start boosing till 4,000 rpm, however i guess this wouldnt be such a problem with the larger engine, so is the T3 or a GT17 going to be my better choice now?

Thanks
RIch

[rick.spi]

your best off hiding the recepts so you cant see the damage lol. my engine build has come to around £2700 lol.

markgt is running a 1380 turbo very sucsessfully in his clubman, dont know if you saw the dyno prints in the turbo minimag issue but the dyno graphs did show his having less lag than the others, obviously this could be many things but im sure most of that is down to the bigger cc's. there probably not a massive gain in goin 1380 but there is definitly a gain.

yes if you were turboing a 998 a t2 or a gt17 would be ideal. the gt17 is a good option on a big bore aswell, and many turbominis members recomnded that to me, im sticking to a t3 for now tho as mine is in good nick.

Edited by rick.spi, 11 April 2010 - 09:59 PM.