998 or 1100?
Turbo Mini Forums

ive had a read up in here on this but cant decide which to do. i have both engines sat in the garage. any pros/cons i should consider? cant make my mind up!

mic

998	4 Votes - 0%
1100	11 Votes - 0%
1100 with 998 crank	1 Votes - 0%

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ther'll be no issues over reving the 1100 so i recon it'd be a waste not to

I'd go for the 998 assuming that you have a A+ block, much stronger than the old A series.

Also, the limiting factor will be the engines breathing capacity rather than displacement.

The 1100 crank must be weaker, so why use it?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I'd try the 1100, as the long stroke crank coupled with forced induction would make a great torquey motor.
If anything, I'd put the 1098 crank in a 998 A+ block.

why use 1098 crank in 998 A+ block?

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because it will fit and the casting is stronger...?

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

An 1100 with a 998 crank would be nice. As the 1100 infact IS a long stroke 998. So, an 1100 with a 998 crank is a boggo standard 998

what about the extra 100cc?

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That comes from the extra stroke so it tends to follow the 1098 crank around!

1100 block and 998 blocks are critically the same, bar the differences between A and A+

my understanding was the 1098 crank has a longer throw and shorter pistons, and thats about it

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

oh, the 1098 head might be the 12g202 casting, which is just over 26cc and is much better than the std A+ 998 head.

Bolting this onto the 998 A+ will lower the compression significantly and allow higher boosts to be used before pinking :)

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

I would use the 1098 crank in the A+ block as the A+ block is stiffer, and this is what the 1098 crank with its long stroke can suffer from (bearing cap flexing leading to spun bearings. A centre main strap is a MUST on the 1098 crank)

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dont think so, definately not in std form.
problem with most 295 heads is theyve been skimmed loads to get the compression down for na applications.

theres a thread on just this in this 998 section worth checking out.

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

A couple of points to consider:

There are two different 1100 cranks according to Vizard, one with 1.75" mains the other 2" so may not necessarily interchange.

He also states on page 363 of the BYB that the revs on a 1100 should be limited to 7000rpm.

Given that we know that a turbo 998 will rev to at least 8000rpm, the benefits of the additional capacity of an 1100 can be ignored if you are looking for all out peak hp.

998 wins from every angle

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

The 1100 cranks with the larger mains are only fitted to the inline Sprite/Midget engines so no problem there with Mini stuff.

It is correct that the 1098 revs need to be capped at 7000 or really 6500 is better, but I personally feel that using the torque advantage of the long stroke crank allied to the torque multiplication of the turbo would work well!!

What about pistons?

I nearly abondoned my 998 project because of a lack of good pistons for turboing.

At least now there are the Mega flat tops that with a 12G295 will give a decent CR for turbo use.

No such pistons exist for the 1100 to my knowledge. Can you even buy replacement stock pistons for the 1100?

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I think pistons will be the problem with an 1100. Revs probably won't be an issue. From our 998 we had 140 bananas and that engine only reved to 6500 at best.

http://www.twin-turbo.co.uk
http://www.hillclimbandsprint.co.uk/default.asp

A man without a project is like a like a woman without a shopping list.

You can get GOOD Hypatec 1100pistons from Australia. Check the Minimania forum.

im using hypatec 60+ pistons in my 1100 turbo , you can also buy omega forged 1100 60+ pistons from swiftune


iv had no problems with revs with mine and im using an A block and no cetre main

1100 ALL THE WAY:)

1152cc turboed mini clubman, most powerful 1.1L a-series?

http://boostmini.justboard.net/

the 998 will rev alot better that the 1098 and alot smoother because the bore/stroke ratio is closer to 1 than that of the 1098. i have no experience in turboing mini motors but my 998 loves revving and its smooth to. its a bog standard mini city e with just over 65k on the clock i love my mini

Why rev the socks of something when you've got maximum torque at 4000 and max rpm at 6K?

On this forum we don't tend to "think" as much as on other forums either. We either have experience on stuff, try or shut up.

Mic, thought you where going the Rover K 16V route???

I have used both over the years, not turbo'd though, and I have to say I prefer the way a 1098 drives on the road for exactly the reasons Tom suggests. For the track a 998 is great fun (had the needle off the standard rev counter regularly on my trick 1040 and it kept coming back for more!!).

Same as much to do with engine tuning really. The first question should be what am I going to use it for?????

Every day is a school day ...........

How fast and how expensive ...... the same question...

i am now but when i first posted this i hadnt quite made up my mind!
but maybe it could be a useful thread for anyone else less experienced who wants to know

Edited by mic on 28th Dec, 2006.

www.retromods.co.uk

Vegard is right. Although you could build a 998 turbo to rev to silly rpm it'd be pointless. For instance I've seen around 140 bhp at 6k on a 998.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

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