General 1242 turbo tuning

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General 1242 turbo tuning

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on the turbo car a peugoet 34mm throttle body has been fitted and i want to no why this item is fitted and not the 40mm body i want (and hope to fit), but dont no if anything has been changed on the manifold etc to fit the french item, has anyone heard of a turbo with a peugeot body on it? also the rs2000 or coupe turbo fuel pump,,,when fitted what will have to be the next step and how do i go about the pressure regulator?
once these are done the head is coming of and a thicker (or twin) head gasket is going on to lower the comp and the head is getting ported poilshed and bigger valves fitted and manifolds ported to match,and im having thorts on having the cam reprofiled to? then along with the intercooler im going to run the 0.5bar the car runs now for safty. either water injection or boost control is something im going to do too!. any advise or opinions on that set up? ;)
 

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the PSA throttle body is just a cheap way of getting a larger throttle body, as they are both webers, so is a pretty streight swap.

Isnt that Petes old car?
 
OK, from the top.

You've got to work out what you want to do with the car.

The first decision is probably whether to stick with the MF2, go for an aftermarket ECU (say, Megasquirt or Emerald) or one of the Greddy piggy backs (like Martin).

If you're going aftermarket it makes sense to go MPI.

This makes decisions about the existing TB pointless, as most suitable set ups will either be different or simply bigger. See here

Or, if you're staying SPI, put a Tricker on. It should more or less go straight on. You can then put the Pug one on your NA car. Martin's car used to have a Pug TB.

An intercooler will help and add to reliability. Check with Pete to see if he's popped in a better fuel pump.

You really need to calculate what the CR will be with either a decompression plate or a solid HG. Two head gaskets are not a good idea. You'll probably find this puts the cam timing out, so you'll need an adjustable pulley.

Forged pistons make more sense to me.

Bigger valves are unlikely to help, and likely to have a bad effect on the exhaust side. Porting is a good idea providing the person doing the porting knows what it's for.

You might talk to Piper about a cam, but make sure they know it's for a charged motor.

Aaron's (J333EVO) post on the development of Blue and on the cooling system andthermostat are well worth reading.

Two places you can easily pick up power are the exhaust manifold and exhaust.

Recommended/essential reading: Mark Warner, Street Turbocharging and A Graham Bell, Forced Induction Performance Tuning.

Perhaps the main thing to remember is that conventional NA tuning logic doesn't apply to these engines.
 
It's one of the great dilemmers that we a have all faced what to do next! My idea when i bought mine, was to just run the car as is as my engine is about as good as it gets on a 1108 SPI but you know how it is :idea::cry:

I have never read as many technical specs and searched as many forums and generally read so much as i have since i bought the car. In the end I think we all just want to make our cars there own and take the development one stage further (subconciously i think to stop it being refered to as so and so's old car)

The whole issue with the VAD setup is that it did the job but it had no real built in safety features as more modern setups can handle so things could go wrong very quickly (which is why VAD stopped making the Hi-Boosts) and hence why fingers is going for emerald ECU (after melting a piston), others have done Megasquirt ECU's, some have used other type piggybacks (tricker) and why i'm looking at a greddy piggyback to replace the MF2 setup. But again there is no right or wrong way and the choice is down to you again i think we all like to be a bit individual in the approach to be a bit unique.

To swop to the 40mm TB is quite easy if you get one straight from Tricker it comes with spacer and gaskets (although i'd use some holymar too) and it is a straight swop, only problem is he is out of TB's at the moment so you will have to send him one to rework, (i've got a spare one PM me if you're interested) As your's has a PSA TB already it will have the TB linked out of the cooling system so you'll have some unused connections when you put a Fiat one back on and will have to block up some others too that are used on the NA setup although if you ask Tricker he will do that for you.


For fuel pump swop and FPR there are some posts with the details on this again by Aaron just have a quick search

If you are wanting to lower the CR then Ferriday make decomp plates and they are a much better solution than twin head gaskets also as you are using a 1242 you could swop the pistons for the ones from the 16v as Tricker and Lenny have done the dishes in the piston lower the CR nicely and there is no need to worry about vernier pulley's

Oh don't forget Cool spark plugs when you swop them don't use hot ones
 
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fantastic thanks for the advise, guess ive just got to sit down and plann it properly before i go ahead with the work! the car is worrying me at the moment the hesitation at low revs (of boost) is quiet bad now,the car will hold back and misfire till the turbo comes in and then the power curve is spot on no probs, soon as the revs drop to around 2000-2500 the holding back on the engine starts again under even light throttle, changed the plugs to super 4's today and changed the oil and filter and found that the MAP sensor pipes were badly split so i cut them down and slipped them back on but this has not cured the problem, i still need to check the H/T leads but ive still got a feeling this may be a fueling issue or a faulty sensor??
ow and unluckly my exhaust snapped in 2 today aswell !! lol, taking it for the middle box replaced with a straight pipe instead because the car was noticeably quicker like this.
 
It's one of the great dilemmers that we a have all faced what to do next! My idea when i bought mine, was to just run the car as is as my engine is about as good as it gets on a 1108 SPI but you know how it is :idea::cry:

I have never read as many technical specs and searched as many forums and generally read so much as i have since i bought the car. In the end I think we all just want to make our cars there own and take the development one stage further (subconciously i think to stop it being refered to as so and so's old car)

The whole issue with the VAD setup is that it did the job but it had no real built in safety features as more modern setups can handle so things could go wrong very quickly (which is why VAD stopped making the Hi-Boosts) and hence why fingers is going for emerald ECU (after melting a piston), others have done Megasquirt ECU's, some have used other type piggybacks (tricker) and why i'm looking at a greddy piggyback to replace the MF2 setup. But again there is no right or wrong way and the choice is down to you again i think we all like to be a bit individual in the approach to be a bit unique.

To swop to the 40mm TB is quite easy if you get one straight from Tricker it comes with spacer and gaskets (although i'd use some holymar too) and it is a straight swop, only problem is he is out of TB's at the moment so you will have to send him one to rework, (i've got a spare one PM me if you're interested) As your's has a PSA TB already it will have the TB linked out of the cooling system so you'll have some unused connections when you put a Fiat one back on and will have to block up some others too that are used on the NA setup although if you ask Tricker he will do that for you.


For fuel pump swop and FPR there are some posts with the details on this again by Aaron just have a quick search

If you are wanting to lower the CR then Ferriday make decomp plates and they are a much better solution than twin head gaskets also as you are using a 1242 you could swop the pistons for the ones from the 16v as Tricker and Lenny have done the dishes in the piston lower the CR nicely and there is no need to worry about vernier pulley's

Oh don't forget Cool spark plugs when you swop them don't use hot ones

ow and yes im interested in the tb you have more info please? (y)
 
I also found this posted by Aaron. The upshot is that past the turbo you just want to get the gas out as quick as possible!

Ah, yes, the VAG intercooler pipes (that is, the intercooler itself) have an o/d of 1.5".

The off throttle stuff. Does it happen when the car is cold? If not could be lambda. Otherwise, suspect the MAP. Often the pipe will be OK, but the rubber bits at each end will be buggered.
 
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I also found this posted by Aaron. The upshot is that past the turbo you just want to get the gas out as quick as possible!

Ah, yes, the VAG intercooler pipes (that is, the intercooler itself) have an o/d of 1.5".

The off throttle stuff. Does it happen when the car is cold? If not could be lambda. Otherwise, suspect the MAP. Often the pipe will be OK, but the rubber bits at each end will be buggered.

thank you, thsi is whu im getting rid the cars centre box, once the exhausts broke the differance in performnace was quiet suprising, and to be honest no the car doesnt really do it as much when cold , mainly when warm so i had the MAP sensor in mind but never though about the lambda, it surposed to have had one fitted not long back but could be that, spoiles the drive alot becaust the car will pull from low down great but when it decides to play up the car holds bad badly and im left waiting for the car to get up and go in most gears.
as for the intercooler,,,so im looking for a cooler with around a 1.2" diameter inlet/outlet then great thanks i better get looking then! (y)
 
Hesitation coming on boost means its running lean, get it checked out, or follow the guide further on to turning up fuel pressure, it should sort it out.

If I was you I would go one of two routes, you need to decide which it's going to be, extract as much as you can from the low-boost set up or go high boost.

Hi-boost, you need to lower compression, I would then get hold of some 1.2 16V pistons and there you go 8:1 compression ratio, perfect. You will also need to at tehis time fit a better fuel pump and set up the pressure regulator the way i designed, otherwise you will not get benefit of the extra regulator. Its to do with having things in series or parallel.

fittingfuelpressureregulator.jpg


Or keep it as low boost as it has been a reliable car so far.

Though with either you can still get head work done, proper gasflowed, port matched inlet manifold from a early UNO 1L FIRE Spi, its a batter design than the Cinq one. 40mm Tricker Throttle body. And I would raise the fuel pressure at the original regulator to 1.4 bar to ensure a good fuel delivery. This is a wax seal at front of throttle body, pick out turn clock wise to increase, use a gauge when doing it, and measure upstream from regulator, not down stream.

1.4 16V flywheel and clutch to ensure you get no slip, although I know this car only ran about 85bhp so a fair bit lower than hi-boost models and not close to the threshold of clutch slip which is about 110lb ft, remember clutches are rated in torque not BHP.

Induction kit moved so it does not sit in a hot engine bay, it will rob it of power on hot days, make straight run from turbo to up high inside the passenger side wheel arch behind the plastic arch line, it's dry and cold, perfect, this is where it is on Martin's car.

A decent bespoke exhaust system, made by someone who knows about what improves a cars performance, not just putting a big pipe on and shiny tailpipe. The exhaust on these cars a restrictive as all the off the shelf ones are made for N/A cars, so are far to restrictive on turbo's car where you want little back pressure, N/A you need back pressure for them to work, this alone could free up a few ponies. I personally would not remove the CAT, but put a new freer flowing one on as the differance in power is very small, at most 2-3bhp and your car will run cleaner and pass MOT's or road side VOSA checks which are becoming more common place now.
 
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thankyou for that, didnt realize you had replyed to the last post, thats heplful seen as ive just been asking questions that are answered here :) hope it isnt running lean the air/fuel gauge never shows this but then to be honest im not looking at it when im putting my foot down (when the hesitation happens)
 
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