So the state of play is 92\' FD nicely rebuilt and ported by WGT a couple of thousand miles ago, also has big exhaust, HKS filters and an Apexi PFC and a nice new set of Toyo R888\'s bought today!. I reckon the intercooler is the next weak link although I quite fancy water injection as an interim. What I need is just to add some safety margin for running track days with a bigger better intercooler - thing is I don\'t really want to shell out another £600+ if I can adapt something from another car.
Has anyone done this? think this is the right step next?
cheers
Why not try water injection alone? It would be cheaper and should work well on stock twins.
Get the quantity right (about 10% - 15% against fuel going in) and it should work very nicely!
Just a suggestion, it\'ll save you a bob or two!
If you go for a large intercooler, then you\'ll also probably have to look at your fuel system and, if you do not already have one, a programamble ECU.
QuoteOriginally posted by maximtaylor
Why not try water injection alone? It would be cheaper and should work well on stock twins.
Get the quantity right (about 10% - 15% against fuel going in) and it should work very nicely!
Just a suggestion, it\'ll save you a bob or two!
Have you tried water injection? I had a home made kit on my TII and it worked well. It did add 2 to 3 psi of boost also.
QuoteOriginally posted by GaryS
If you go for a large intercooler, then you\'ll also probably have to look at your fuel system and, if you do not already have one, a programamble ECU.
he said he\'s already got a PFC :)
An intercooler is a good way to go, remember to cost for fitting as well as front mounts are a pain :)
QuoteOriginally posted by davefrith
he said he\'s already got a PFC :)
An intercooler is a good way to go, remember to cost for fitting as well as front mounts are a pain :)
But not uprated fuelling. Remember 100% injector duty cycle normally means a big bang and a large bill.
QuoteOriginally posted by GaryS
But not uprated fuelling. Remember 100% injector duty cycle normally means a big bang and a large bill.
I\'m sure 100% is okay - problems arise when it tries to go to 101% ;)
Iain
I would like to see you persuade an injector to run at 100% with out the engine going bang:rollin
When i was adding injectors to my TII i put 12v DC into an injector to test it, with in seconds, it was too hot to touch.
I know fuel will obviously keep it cool, but if it runs at high % cycle it must heat the fuel up. Just something else to ponder in the everlasting search for safe power in a rotary!:confused:
QuoteOriginally posted by iaint
I\'m sure 100% is okay - problems arise when it tries to go to 101% ;)
Iain
I wouldnt want to see anything above 90%.
Fish
Cool (or hot!) - would never have thought that they\'d get that hot that quickly!
on 0.9 bar mine are peaking at 87% so that\'s happy.
If, hypothetically speaking, one were to upgrade the intercooler (maybe something v-mount sized rather than full fmic sized) and didn\'t have the resources to sort fuelling completely (i.e. pump and injectors) would running at 0.7 bar boost be possible to keep fuelling safe? Would running a bigger pump/pressure regulator be possible without upping the injectors?
Iain
That would be a short term fix.
Fish
That\'s what I was wonderin\' :)
Iain
Bigger injectors? Why would I have to alter the fuelling by changing the intercooler? The amount of intake air and threfore fuel air ratio would be unchanged, wouldn\'t it?
The initial thought was to reduce intake temp for more safety margin, thats all.
I already have an apexi pfc and tweaked map for the ported engine. Presumably though, if I where to put a bigger i/c in, I would then have potential to run more boost/power and thus require more fuelling, yes?
Putting a bigger intercooler on will lean out the fuelling.
You might just get away with fitting an uprated pump and FPR.
Fish
wouldn\'t this depend on the size/effectiveness of the intercooler though? :confused:
Lower intake temps = more oxygen in the same volume of space at the same pressure. Granted that means more fuel, but not necessarily lean running if your injectors/pump/etc. have enough capability in them?
or have I got it all wrong again...:rolleyes:
P.S. - how do you measure the injector cycle duty?
As my injectors are currently peaking at 87% when tried on 0.9 bar I might get away with upping the I/C and, once mapped run them at 97% (for example).
This is way too close to the edge for my liking and, on a cold day may push them to the limits. It only takes a second to throw a tip!
I\'m looking at a change to my intercooler setup (hopefully) but don\'t have cash to throw at it so I\'m hoping that I can either get some decent injectors at a bargain price or, preferably, get away with a bigger pump and a regulator.
Looks like I won\'t be able to reduce the running costs to < 1k per month this side of chrimbo!
Bottom line is what you can afford vs how lucky you feel! Being unlucky is expensive!
Iain
You can up your fuel pressure and get ecu remapped and it will provide more fuel. Intercooler will flow loads more dense air whether front mount or vmount or stock mount and you will definitely hit 100%. Hitting 100% isn\'t going to do anthing to the fuel that would enhance the risk of detonation.
Theirs two kinds of 100% first is 100% but supplying enough fuel to maintain a good safe air/fuel ratio running like this for extended periods will heat the injector up and may cause injector failure. and the other type of 100% is when your at the max duty cycle but injectors are unable to cope with supplying enough fuel. therefore running lean and enhancing the risk of detonation.
rgds
Both sound like something to avoid. Obviously best route is to do injectors and pump (along with remapping). Anyone case to suggest sensible price for injectors and pump?
Iain
Yeah, I could. :p
Fish
Yep, running an Aquamist 1s system, with a 0.9mm nozzle at the moment. I already run low intake temps (30 degrees under load normally), but as soon as the water kicks in, the temps plummet!
I\'m running a pair of 1300 secondary injectors (for the time being), and even with fuel pressure upped by about 22% I\'m still seeing 80% injector duty at 0.8 bar.
Next project is Bosch 1600\'s.
Max
QuoteOriginally posted by spanerhed7
Have you tried water injection? I had a home made kit on my TII and it worked well. It did add 2 to 3 psi of boost also.
QuoteOriginally posted by maximtaylor
Yep, running an Aquamist 1s system, with a 0.9mm nozzle at the moment. I already run low intake temps (30 degrees under load normally), but as soon as the water kicks in, the temps plummet!
I\'m running a pair of 1300 secondary injectors (for the time being), and even with fuel pressure upped by about 22% I\'m still seeing 80% injector duty at 0.8 bar.
Next project is Bosch 1600\'s.
Max
30 degrees! What intercooler are u runing to get that low? or are you the only guy in antarctica with a Rex?
Max has an Apexi GT-spec front mount.