37 replies to this topic

[stevenford_uk]

i have just secured a deal with a mate for my old spare turbo lump

he wants at least 170bhp from it, so i have told him the following:

rebore to bout 1290
low comp pistons,
combustion chambers enlarged to lower compression ratio further,
wild porting
avonbar ultimate turbo cam
set of roller rockers
T3 turbo running bout 17psi
steel headgasket
total carb rebuild and rejet to suit
straight cut dog box with bronze selectors
at least a 4pin diff
arp rod bolts
shot peened rods
avonbar dizzy
big intercooler
and i am thinking about rigging up an extra injector on a pressure switch so when it goes above a bar of boost it dumps more fuel in. easy and effective
straight through exhaust

is there anything anyone can suggest that i have missed or to make it stronger, as i do not want to have to rebuild this for him every other day

[Oldskoolbaby]

Spray nitrous on the intercooler for when hes feeling a bit naughty :grin:

[Sprocket]

Four bolt center main cap

Oh and have the head and block drilled for 11 studs and fit the ARP Head studs

[Turbo Nick]

i'd go for:
1293cc
forged JE pistons 18cc
A+ rods, shot peened.
turbo crank fully worked
centre main strap
SCCR box, minispares 4 pin diff, SC drops
Morspeed turbo booster head with chambers resized to bring CR down to 7.8 ish
phase 2 cam
ultralight fly, grey dia, paddle clutch.
fully balanced rotating assembly,
1.3 roller rockers,
T3 turbo,
megajolt ECU,
2wd cossie intercooler,
A good session on the rollers (with a decent operator)
17psi boost.

I'd expect that to see 170bhp personally.

[DaveCoxon]

i have just secured a deal with a mate for my old spare turbo lump

he wants at least 170bhp from it, so i have told him the following:

rebore to bout 1290
low comp pistons,
combustion chambers enlarged to lower compression ratio further,
wild porting
avonbar ultimate turbo cam
set of roller rockers
T3 turbo running bout 17psi
steel headgasket
total carb rebuild and rejet to suit
straight cut dog box with bronze selectors
at least a 4pin diff
arp rod bolts
shot peened rods
avonbar dizzy
big intercooler
and i am thinking about rigging up an extra injector on a pressure switch so when it goes above a bar of boost it dumps more fuel in. easy and effective
straight through exhaust

is there anything anyone can suggest that i have missed or to make it stronger, as i do not want to have to rebuild this for him every other day

Here is my suggestions...


rebore to bout 1290.... Yes, Stick to +020"for a nice 1293 turbo engine

low comp pistons, Always useful

combustion chambers enlarged to lower compression ratio further, weigh up between this and dish; personally i'd stick to a 15cc or-so dish and open up the chambers by 'raising' the chamber roof, so as to attain a superior chamber shape, in accordance with the desired CR

wild porting Not overly neccesary - typical stg3 porting is more than enough. 35.6/29 valves are a gfood start and cheap. Leave a nice wide seat on the exhaust valves to get heat out of the valve head quickly

avonbar ultimate turbo cam Nope. Avonbar phase 2 will be more than enough

set of roller rockers yep - but you might want to choose a ratio and set the valve spring height to suit aswell

T3 turbo running bout 17psi You run whatever boost is neccesary whilst operating within the T3 compressor range - or you can just wind the boost up like most and hope for the best. At the least, you need to swap out the stock turbine housing for the 0.35A/R unit - ideally you'll also switch to a larger, more suitable compressor wheel. Personally, I'd ditch that piece of antiguated C**p and get a decent turbo on there.

steel headgasket Stock Payen BK450 will suffice (£6), non of this steel ********. Standard Rover studs if you have them, and they haven't been abused - if not, then ARP all the way

total carb rebuild and rejet to suit ...and changing out the bi-met jet holder, the over-run butterfly, and the dashpot spring

straight cut dog box with bronze selectors Stock selector forks are bronze aren't they? And a Dog box? for the road? Why on earth would you do that?

at least a 4pin diff at least

arp rod bolts good belt and braces

shot peened rods I'd be more concerned about polishing out the sharp edges, balancing and checking the big-ends for ovality

avonbar dizzy or just modify your own by reducing the total advance, or go straight to Phil Hepworth 01925636959 and get one from him - OR do the ONLY decent thing and put a dizzyless ignition on it

big intercooler How about choosing an efficient intercooler that'll do the job, rather than thinking bigger is better? I'll go with Bud's suggestion here though - seriously cheap, and one of the most efficient core designs around

and i am thinking about rigging up an extra injector on a pressure switch so when it goes above a bar of boost it dumps more fuel in. easy and effective What what what?????

straight through exhaust "Sorry Officer, yes - i'll bring my documents in within seven days. Yes, i'll also get that exhaust sorted and get the vehicle defect notice signed by an authorised test station and bring that in aswell..."





I am wondering - are you going to be building this engine for him? don't get me wrong, but it sounds a bit 'shopping list' than 'engine build' to me...

Buds list looks like a real 170banana contender - but it also depends how many bananas you're REALLY after, and which RR you go to to find all these bananas...


To add:
Centre-main strap if you want - check centre-main ovality before and after machining.
No wedging/blading nonsense on the crank. This is a 7Krpm MAX motor.
Undercrown cooling jets.
Fully prep'd block
Avonbar sureflow oil pump
Dry-deck if he wants to go that far...
Champion C57Cy plugs
high-tensile 1/4" box-to-block studs
Ulight fly, 270 backplate with 23.5mm machined posts, Grey diaphram. AP road/rally plate
Where does it end???

[PikeyMini]

sorry but how do you know all this?

[Guess-Works.com]

Cause there's a lot of peopl who been there done that got the t-shirt...

Look on the Turbo-Minis forum... http://www.turbominis.co.uk/forums/

[AlexF2003]

sorry but how do you know all this?

because he's done it once or twice

[PikeyMini]

ok fair enough

[DaveCoxon]

I've been into turbo's for a few years - and enjoy getting most out of them, which to me doesn't simply involve a bleed-valve big intercooler. A fuller torque curve, with smooth, progressive power delivery, rather than outright power has always been my primary aim.

My mini is here:
http://www.mancheste...s/turbodave.htm
But that hasn't been updated for many years.

[frostie]

that is a very nice car.
can i ask....have you got flexi-braided hoses from the brake cylinders all the way to your calipers?? i would love to do this, but have been told that they can "wriggle" and basically move around when braking which means they can be less efficient?
any ideas?

[DaveCoxon]

Nope, Brake master to servo, servo to bulkhead tee-piece. All the rest are solid lines - as they should be!

[frostie]

kk thanx!

[Sprocket]

Phil Hepworth 01925 636959

Interested to know more about this chap What sort of work he does and where he works/ owns Is that if the number is right he is in Warrington

[stevenford_uk]

thanks for the replies guys, i was in a bit of a hurry with him sitting next to me bugging me to ask because he didn't trust my judgement in what he needed.

the blocki have got already has a centre main strap, i have a t3 turbo off a renault 21 turbo for it, so ill swap the comp housing off the 21t T3 and bang it on the metro turbo unit.
i have a cossie 2wd intercooler sitting at home which i didn't think about.
thanks for the comments on the head studs, they had totally slipped my mind.
i dont want to go near nitrous for him, because it will benifit him when he has got the juice but when he runs out he'll be expecting the same kind of power etc and it just wont happen, so i am staying away from nitrous.
i have been looking into megasquirt kit, so i could fuel inject the mini, use a ford edis system, and a throttlebody etc off a mondeo 2.0l or something, plenty big enough to flow whatever boost he wanted and cheap and easy to pickup.

why should i go for the stg2 instrad of the avonbar ultimate?? i always believe if there aint much price difference in something that will allow me to go further in the future go for that instead of the one that will do for now.

as for the head i will be doing that myself with some help from my dad, he has been porting race bikes for years and i did my mazda mx5, so i know the crack there, i also have very detailed pictures of a "work of art" turbo head.

straight through exhaust is a must, anything that pisses off the babylon more than my car is better!!!
best for power and safety for the engine, so ill do it happily for him, lol

i recently got rid of a very very fast renault 21 turbo which i played around with from the std 175bhp and 199ftlbs torque to 248bhp and 249 ftlbs torque no further up the rev range, and only running 2 psi more than std!

so i know the crack with turbos, just for those with doubts over that 1st post lol
thanks again guys