Supercharging

[Ste]

Ill try to keep this as short as possible. But it wont be easy and im mainly doing this for the search as theres not much that comes up. Im going with a supercharger for my car and at the moment im still making sure i know what im doing so theres a few other questions. But in the first stages im only wanting to touch 200bhp. Then when the problems have been ironed out id like to push for 250bhp but i want the engine to be capable of handling more so in theory im running it de-tuned. Engine is a MK2 16v.

Internals


Wossner forged low compression pistons with rods. - Roughly £1000. Simple choice but Do i upgrade the piston rings with different pistons or will the OEM ones be ok, and will they seal in the head ok?.

Or

Is it worth going for a stroker kit with the rods and pistons to put the engine up to 1.8 which would aid in getting the power i want without stressing the engine as much, but its a massive cost and a large chunk of my budget so if its not going to give that much of a gain or be unreliable i can forget it. - £2000

Also will have a baffled sump, but the new charger (Rotrex C30/64) has its own sealed & cooled oil supply so its only for the engines benefit.



Management

Im going with a megasquirt, mainly because its so adjustable, cheap, i can write software for it and i can learn to do the mapping myself. Id like to learn about telemetry too and you have to start somewhere. Are there any reasons why i shouldnt go with a megasquirt?.



Fueling

Ill be increasing the fuel pressure and uprating the injectors when needed, all this will be properly dialed in with a wideband & the megasquirt, but after some calculations read from another thread i dont think ill need to uprate the injectors until i go well above 200bhp. Can anyone confirm this. Also would i need to upgrade the fuel pump to get my target?.



Drivetrain

Ill be fitting a Quaife diff and keeping the VTS box with a lightend flywheel and maybe change the final drive depending on the results after a few track sessions whether i need more accel or top end. Also i know the valeo clutch is pretty good, will it be ok with 200 - 250 bhp or will it just tear itself up?. (I drive sensible on the road and the car rarely comes out).



Cooling

Thermostatic oil cooler, mounted right behind the front right foglight hole. Ive made some custom fibreglass brake ducts to help keep the brakes cool (not needed i know but its unique).

Ill get the biggest intercooler i can get behind the front bumper without any chasis modification and if needed fit a charge cooler or a set of small fans if the temps dont stay down. Anyone fancy sharing your choice of intercooler?.



ETC

The supercharger kit will be coming from GMC, however i dont know what pulley size relates to what boost pressure and until i start buying the kit i dont think GMC will want to answer any questions. Which is understandable.

So does anyone know what pulley size is best to start off with?.


I have a ported & polished head with newmans PH3's, do the cams need to come out when using boost and can i use the ported head?. If so which cams would be better - bearing in mind im more interested in a smooth torque curve than figures.

Head bolts & gasket, with the boost and high compression should i get a decent set of head bolts and a competition gasket?. Or will OEM new replacements suffice?.

I have the GMC 4-1 Manifold with a piper full system (no cat) is this free flowing enough or will the piper centre section be a bit of a bottleneck.

The plastic inlet has always been the downside to the 16v, im thinking at first ill run it with the standard inlet. But then as it progresses, im goingto use a set of throttle bodies with a plenum. Theres a few reasons for this, but number one is looks and have a more unique engine, number two it should give a much smoother power delivery with a properly designed designed plenum and inlet mani. Different size TB when boosted?, and any reasons why i shouldnt?.



As always all advice appreciated, and thanks to everyone who has already helped out, the project starts in Jan, ive got just enough cash saved to buy the charger kit and pistons, the rest will be done as i go, and i dont think it will ever finish. Im hoping to have it running with everything purchased by early summer and have the lot done this time next year. All the work will be done by Ricky P RPM as he's shit hot.

[boz]

chat with john from gmc about the injector size, fuel pressure, fuel pump, pulley size etc

he can keep you right

i think that the gmc pace intercooler and rad are spot on, they are a perfect fir for the car and dont need any mods ;)

you will defo need a clutch mate, the valeo one wont be up to the job for long. i would go for helix or AP racing clutchs along with the lightend flywheel that you can get with them. im not sure if anyone has used the megasquirt system on a boosted saxo or pug yet??

head gasket wise go for a cometic competition head gasket ;) and arp bolts.

TBs with a SC dont mix to well, i only know of one car that runs them and thats sybez of ssc, he cars is sweet but hardly on the road.

the standard airbox is ok for big boosted power.

but why not have a look at dp engineerings bespoke inlet, ally, enclosed with one bigger TB and 8 injectors ;)

or why not try the inlet setup off a sunny gtir, they come with throttle bodies already inside of an ally inlet, and its already designed for boost ;)

other wise it all sounds good ;)

enjoy filling out the cheques ;) lol

[boz]

dont be scared of john, he knows his shit. but bear in mind, he will be funny at first as he will hear the 'i want to run a SC on my saxo' about 10 times a week, with no avail lol

not to sure on the ph3 cames, im going to chance it and use them on my TB setup, i know of guys that have used 708s with boosted cars with no probs, the ph3s are very similar and arnt a mega wild cam, so you shouldnt suffer from blow buy. just make sure you fit uprated springs etc

[Ste]

enjoy filling out the cheques ;) lol


Tell me about it, its so hard to save up and so easy to spend!.

Thanks for the info.

[boz]

no probs, i have been down this route twice matey.
i know your pain lmbo

[boz]

go for the biggest sc that john recommends, then if need be fit a reducer into the inlet ;)
always better to do that than it is to upgrade to a new one!

[gd16]

Wow - far too many questions to answer at once. I'll get a few done just now;



Internals


Wossner forged low compression pistons with rods. - Roughly £1000. Simple choice but Do i upgrade the piston rings with different pistons or will the OEM ones be ok, and will they seal in the head ok?.

Or

Is it worth going for a stroker kit with the rods and pistons to put the engine up to 1.8 which would aid in getting the power i want without stressing the engine as much, but its a massive cost and a large chunk of my budget so if its not going to give that much of a gain or be unreliable i can forget it. - £2000

Also will have a baffled sump, but the new charger (Rotrex C30/64) has its own sealed & cooled oil supply so its only for the engines benefit.



Pistons will be more than enough to begin with. Rods are really only needed for extreme power and/or high revs.

If you are even thinking about getting a stroker kit - i'd hold back on buying rods until you decide. No point buying forged rods now, then having to buy new ones again if you go for a stroker crank.

Baffle sump is a good idea if you're spending a lot on fancy internals.




Fueling

Ill be increasing the fuel pressure and uprating the injectors when needed, all this will be properly dialed in with a wideband & the megasquirt, but after some calculations read from another thread i dont think ill need to uprate the injectors until i go well above 200bhp. Can anyone confirm this. Also would i need to upgrade the fuel pump to get my target?.



If you spec the injectors correctly - there's no real need to upgrade the fuel pressure. Any reason you think this is necessary (curious)? From what i've read standard injectors won't cope with much over 170bhp. Would definatly uprate them - and make sure you uprate them enough so you don't need to rebuy again later.

I would advise instead of uprating the standard pump, getting a 2nd one and swirl pot. Using the standard pump you'll eventually run in to trouble with fuel starvation - so best sorting that first, before you over-compensate with putting the injector pulses higher.


Drivetrain

Ill be fitting a Quaife diff and keeping the VTS box with a lightend flywheel and maybe change the final drive depending on the results after a few track sessions whether i need more accel or top end. Also i know the valeo clutch is pretty good, will it be ok with 200 - 250 bhp or will it just tear itself up?. (I drive sensible on the road and the car rarely comes out).


Personally wouldn't fit a lightened flywheel as it'll rev quick enough as it is. Diff is definatly a good idea. Again - spec your clutch for the power you want eventually, not to begin with, again - get the right stuff first time.



Cooling

Thermostatic oil cooler, mounted right behind the front right foglight hole. Ive made some custom fibreglass brake ducts to help keep the brakes cool (not needed i know but its unique).

Ill get the biggest intercooler i can get behind the front bumper without any chasis modification and if needed fit a charge cooler or a set of small fans if the temps dont stay down. Anyone fancy sharing your choice of intercooler?.


Can't beat the GMC intercooler IMO. Fits perfectly and takes up the full hole in the slam panel.

[boz]

Can't beat the GMC intercooler IMO. Fits perfectly and takes up the full hole in the slam panel.

looks like an OEM part ;)

[Ste]

Thanks V Much BOZ & GD16!.

Am i right in thinking with a swirl pot you have 3 inlets and 1 outlet, you have a pump pulling from the tank (oem) and pushing to the inlet in the swirl pot.

Then another pump pulling from the swirl pot outlet and pushing to the fuel rail from the swirl pot and the fuel return from the fuel rail to the input on the swirl pot not the tank.

The outlet at the very top of the pot is a return to the tank.


Also what size swirl pot would be needed for this application?.

The injectors, thanks to GD16's maths, required are 350cc. How do i know?, GD16 provided this equation;

(BHPx5.6) / Cylinders. So it works out 250 - my target BHP x 5.6 / 4 - saxo cylinders.

IE;

(250x5.6) / 4 = 350.

With that a 380cc jet will be perfect.

[gd16]

The injector equation is out of a book 'Forced Induction Performance Tuning - Graham Bell' - but i'd double check when buying the injectors that its suitable for you're application.


You can set up the swirl pot in two different ways. Either with a total of 3 in/outlets, or 4.


With 3, standard pump feeds swirl pot. Then another outlet feeds the second pump. The third outlet you T with the fuel rail return to the main tank.

With 4, standard pump feeds swirl pot. Then another outlet feeds the second pump. The third outlet is the return from the fuel rail, and the fourth is the return to the main tank.


You can spec you're swirl pot however you like - but the standard size tends to be fine. Jim @ Alloy Racing Fabrication ( http://www.alloyracingfabrications.com/ )did mine with the outlet sizes i wanted in the positions i wanted.

Can't remember the maths off the top of my head, but fairly easy to work out the max fuel rate the injectors will do (litres/minute), and fairly easy to calculate the volume of a cylinder and therefore the litres held. Then can work out how long the swirl pot will feed the engine. Think mines at least 30 seconds if not more. And bare in mind thats working on the assumption you'll be at full throttle - which is unlikely - and that no fuel is getting through from the standard pump - again unlikely. So plenty in reserve to avoid starvation on long sweeping corners - or through acceleration. I know one of the old school s/c vts (AndyL's) suffered starvation at under half a tank on full acceleration.

[gd16]

ETC

The supercharger kit will be coming from GMC, however i dont know what pulley size relates to what boost pressure and until i start buying the kit i dont think GMC will want to answer any questions. Which is understandable.

So does anyone know what pulley size is best to start off with?.


I have a ported & polished head with newmans PH3's, do the cams need to come out when using boost and can i use the ported head?. If so which cams would be better - bearing in mind im more interested in a smooth torque curve than figures.

Head bolts & gasket, with the boost and high compression should i get a decent set of head bolts and a competition gasket?. Or will OEM new replacements suffice?.

I have the GMC 4-1 Manifold with a piper full system (no cat) is this free flowing enough or will the piper centre section be a bit of a bottleneck.

The plastic inlet has always been the downside to the 16v, im thinking at first ill run it with the standard inlet. But then as it progresses, im goingto use a set of throttle bodies with a plenum. Theres a few reasons for this, but number one is looks and have a more unique engine, number two it should give a much smoother power delivery with a properly designed designed plenum and inlet mani. Different size TB when boosted?, and any reasons why i shouldnt?.




Pulley size - specify when you buy the charger what pulley you want on it. Might take a bit longer to get it, but worth it to get the correct pulley. Not strictly necessary, but the VTS pulleys are prone to falling apart due to the rubber - so may be worth getting a different one (GMC have full alloy ones IIRC).

Fairly easy to work out which pulley is best to go for. Power range and therefore max RPM will be determined by the cam - so once you know you're max RPM (ie 7250), the standard VTS bottom pulley is 138mm. Then depending on which charger you go for will determine its warranty rpm limit (64/74/84 is 12,600 and 94 is 12,000 IIRC)

Then - simple maths again.

(7250/12600) * 138 = 79.4mm

Go for an 80mm s/c pulley and the charger will spin to a max of 12506 at red line, just under the warranty limit. Go for a 75mm, and it'll be spinning at 13340. Not a huge amount over the warranty limit - but remember that more boost does not always equal more power. More boost really means more heat - so unless you can get rid of the heat, not only will you loose power, you'll potentially loss reliability.


Cams can stay in - but often experience blow-through, basically both inlet and exhaust ports are open and the boost goes straight through the engine. I can't really comment more than that, other than i do know cars running cams and s/c.

Ported head would be beneficial - but really unless its had extensive work on it i'd really go for a JP4 head (C2/207 etc etc) - as the valve sizes are a lot bigger. You'll need to swap things from the Saxo head into it - and i've heard of issues with high lift cams causing problems unless the pistons are pocketed.

Exhaust *should* be fine for the power you're going for. I know GMC have just had BTB make up a 3 inch exhaust for there's, as the 2 1/2 inch one was glowing white all the way to the backbox on the rollers. But they've got slightly ;) more power than you're aiming for.

Plastic manifold again should be fine for what you're after. Quite a few on plastic inlets running 240+ @wheels. If you feel you must go metal - look into finding a C2 VTS inlet. Pretty rare, but can be got cheap if you're lucky (got mine for £120, RRP is about £350) - and need a small amount of work to fit. Would advise against throttle bodies, unless you're getting the throttle quadrant sorted. Sybez was moving back to a single inlet before he sold up due to the nature of throttle bodies at low revs. Basically very hard to get small throttle levels due to the s/c and amount of air allowed into the engine at once when throttle plates were opened.

Standard throttle body size should be fine. Again - GMC are getting silly power with (i think) a standard one, and there are ones with 240+@wheels with standard throttle body.

[vlatko_vts]

I think that for start you don't need Rods only pistons. Rods is for high rpm or for high boost. I have a friend and for start hi runs with 7.35PSI or(0.5bar) in Europe. You will need a new fuel pump, I suggest Walbro High Pressure or IN LINE pump, injectors are ok for 185-190hp their size is 210CC but for more HP you will need more fuel. For Ph3 I think it will be better not to experiment and call David Newman for consultation tel.+44-1689-857109. I think the most important thing is to protect engine from the detonation becouse it is the only thing that can broke your engine. Also the most important thing is a good map for your ecu. You will need AEM WIDEBAND CONTROLLER to control air-fuel. I hope that the information will be useful and sorry for my bad English.

[Ryan]

I hope that the information will be useful and sorry for my bad English.

Your english is still better than some users. Thanks very much for putting effort into helping

ryan

[boz]

nice to see people input from outside of the uk ;)

your english is good, you should here how i speak and im from the uk haha :)

[vlatko_vts]

All are trying to help others, I hope you will help me when will I need some information. Thank you for your good words mate :-)

[boz]

im sure if you are in need of any info, someone on here can help you out or find out for you ;)
get some pics of your car up in the phots section ;) i like to see what other people from other countries are doing to their cars :)

[vlatko_vts]

[IMG]http://i426.photobucket.com/albums/pp348/vlatko_vts/HPIM0852.jpg[/IM

This is my car.

[vlatko_vts]

http://i426.photobucket.com/albums/pp348/vlatko_vts/HPIM0852.jpg

[vlatko_vts]

I finally managed :-)

[vlatko_vts]

Is there any progress or ...?

[vlatko_vts]

Hey, I just bought newman cams PH3 for my Saxo-VTS from David, I still didn't try to install them because I'm short with time, so I was just wondering and would like to ask you guys for help. Is there any things that I should keep an eye closely, any secrets during instalation or else? My bigest thinking problem in this moment is correct timming. I know that the Saxo comes from factory with adjusting cam gears, so will be needed any special setup or. So I was wondering if any of you have any good advice, picture, or any other info about this I will be more than grateful. Thanks

[Ryan]

Hey, I just bought newman cams PH3 for my Saxo-VTS from David, I still didn't try to install them because I'm short with time, so I was just wondering and would like to ask you guys for help. Is there any things that I should keep an eye closely, any secrets during instalation or else? My bigest thinking problem in this moment is correct timming. I know that the Saxo comes from factory with adjusting cam gears, so will be needed any special setup or. So I was wondering if any of you have any good advice, picture, or any other info about this I will be more than grateful. Thanks

start your own thread rather than posting in lots of other threads off the topic please


you will get better responses