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hi comp engine questions
Posted: Fri Mar 16, 2007 12:00 pm
by 16bit
I was thinking of getting the ffs cold side kit. However I understand that air to air intercooling is out of the question to get higher safe levels of boost for more power. I would eventually like more then 210 whp and was thinking i could build a high comp engine to 'simulate' more boost. If I was to build my motor with 11:1 wiseco's, corrilo rods, arp head and rod bolts, metal head gasket, get an oil cooler, port and polish the head with tighe 805c billets, mazda speed cam wheels, double springs, oversize valves etc on standard levels of boost would this motor be able to handle it. All supporting mods would be done at this stage - alloy rad, clutch, lsd, fuel pump, injectors, ignition, computer upgrade etc. I know this is a big dollar project - I have estimated 35k to get the car up to scratch with these mods. But it would be a bit of a giant killer!
Posted: Fri Mar 16, 2007 4:21 pm
by adamjp
With pistons of that CR you will experience difficulty with detonation whilst running normal ULP and without the SC.
How about:
Get good pistons with a lower CR from ACL, Venolia, Wiseco - pretty much anyone that offers them.
Get the valves fitted well with suitable springs (possibly stiffer on inlet).
Port and Polish head.
Get the exhaust valves and ports ceramic coated by Jet-Hot or similar.
Ask Tighe for camshaft recommendations and then have cams made to suit (won't need cam wheels then).
Turbo or Pauter or Carillo rods with bolts of their choice.
Oil cooler is a very good idea, irrespective of boosted engine or not.
Unless you are running a lot of boost, you won't need to O ring the block and run a metal head gasket.
Get a slightly 'upped' pulley for the Eaton to change the ratio or consider a different kit if you are really chasing big HP. 210rwhp (155rwkw) is fairly strong in an MX5 anyway, sticky tyres and good brakes will still make it a very quick car. If you want a 'giant killer' perhaps you should buy something else as your starting point.
Posted: Fri Mar 16, 2007 4:47 pm
by 16bit
i c so hi comp with forced is never going to be that good. so pretty much what i said but with low comp pistons and ask engine builders advice on things to suit the application.
Re:
Posted: Fri Mar 16, 2007 4:50 pm
by Boags
16bit wrote:i c so hi comp with forced is never going to be that good.
Incorrect. It'll be great if you can stop it from pinging it's head off!
Water/methanol injection to cool the hell out of the charge air would help... As would REALLY high octane fuel.
Boags
Posted: Fri Mar 16, 2007 5:07 pm
by 16bit
yeah apparently the intake manifold with the ffs kit has a drilled a tapped bit for methanl injection (already asked tom). so 100ron race with 4 bottles of octane booster hey!
Posted: Fri Mar 16, 2007 8:10 pm
by adamjp
Hi compression with forced induction is great. You just can't do it on petrol.
As Boags pointed out, methanol will let you do it, but methanol is not street legal and brings a whole bunch of issues to your engine.
You are correct, talk to a good trustworthy engine builder and follow their advice. They may suggest that the coldside kit is not going to do what you want (210rwhp ++).
Posted: Mon Mar 19, 2007 6:34 pm
by 4sfed5
the fact remains that super chargers heat the air up waaaaaay more than a turbo does and the only thing that will stop it from blowing itself up at the sort or Hp you want is water/meth injection......and to be honest im not a big fan of trusting a crappy little water squirter with a nicely rebuilt engine that owes you 10 grand (or 35 grand)..if the jet blocks or your water reservoir runs out....KABOOM!
A supercharged car with more than 200RWHP is beast that needs very very very careful tuning and a careful ear to listen for detonation.
Perhaps look at the new FM turbo kits instead....a nicely sized turbo kit aint gonna give up that much in terms of boost response..and you can run it without water/meth injection. Even a STOCK 1800 engine will happily spit out over 200RWHP in a daily drĂven pump gas turbo setup.
Posted: Tue Mar 20, 2007 8:49 am
by 16bit
as each day goes by everyone is telling me that turbo is the only way to go. I always throught that a turbo would heat the air up alot more due to the very hot exhaust housing sitting off it that tends to glow under prolonged boost periods. the fm kits do look good.
Re:
Posted: Tue Mar 20, 2007 9:24 am
by Boags
16bit wrote:as each day goes by everyone is telling me that turbo is the only way to go.
It's not the
only way, especially if you have a budget as high as you do.
A turbo will be the easiest and cheapest way to produce the power you want legally. Some people don't want the cheapest and easiest option though. It's up to you.
Hell, with that budget I'd smack an SR20 in it.
Boags
Posted: Tue Mar 20, 2007 10:09 am
by Juffa
I would suggest that you get yourself a copy of Corky Bell's high informative book, Maximum Boost. It goes into a lot of detail (some might say too much detail) on every aspect of adding forced induction to your car. Note that the book quite clearly states that turbo is the way to go over SC and from that point on all information is around turbo based installations. Not trying to stimulate the turbo/SC debate.....just repeating what the book says.
I have chosen to go DIY with my turbo build. It started by buying a 2nd hand kit with 99% of the parts, but am now finding that I am changing some parts, based on my reading of the above book, to ensure ongoing reliability.
Just my 2.2c worth (including GST)
J
Posted: Tue Mar 20, 2007 10:24 am
by 16bit
yeah sounds like the go. i have had a look at the fm kit and it is very well priced (500 bucks cheaper then the avo kit - and the avo does not come with management upgrade). I think i will get the car ready to handle boost of the next year with upgrading the rad, clutch, lsd, brakes, braces, sway bars etc then go boost on the stock motor until that lets go. then rebuild. unless i can find a good integra type r in that time.
Posted: Fri Mar 23, 2007 5:41 pm
by 4sfed5
im not sure what year car you have at the moment but if you have a very large budget...it may be better to buy something like a SP turbo and modify that rather than tearing down an entire car for custom everything....
an SP or even SE turbo with a motec m4 pro would be a great little setup.