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Finally got the boost leaks out, and kept from blowing a hose off for a few runs, and I found out my wastegate holds about 11psi?(about 180kpa from MAP sensor). I was told it was an 8psi spring.

The car was running good, finally boosting early without lag, and was amazingly fast. burned out through 2nd gear past 50 mph one time. it would take off at 3000rpm, and responded rite when the throttle opened.

But I believe i slowly blew off a hose(smooth abs pipe,/no rolled edge), and the car started to very slightly ping on the top end. (+ boost was lagging, taking longer to build up, and noticiebly less power). So I was gonna richen up the top end, when I noticed i was running past 100% Duty cycle!

It looks like 30lb injectors simply arent enoguh for 11psi non-intercooled???

And it seems with enough fuel, I can safely run about 11psi non-intercooled on 91 octane Cali gas.

Will Idle have to be very rich if I run 52lb High-impedence because of min pule width? Is it worth it to switch to Low-impedence?

Heres an engine bay pic. Sorry for Low quality Picture and Low budget parts used. Though it may not look great, ABS is really strong, withstands heat real well, doesnt conduct it much and stays pretty cool. And its cheap and easy to work with.

and yes my valve cover vent hose is crimped bad, but it still flows a little, needa fix that.

Below the 3" 90degree ABS elbow, i have a 3" "custom"/home-made 45 degree bend, to a 3" to 2" reducer, then coupler to turbo outlet.

Well,
From straight math

30lb/hr inj is 30lb/60min = 0.5lb/min per injector.

You looking at support of the inj, so take the AFR you want, say 10.5:1 AFR. You wan't 10.5 parts air to 1 part fuel, so...

10.5*0.5 = 5.25lb of air per minute.

You have 6 injectors, so 5.25 * 6 = 31.5lb/min of air support.
Every 1lb/min of air is ~10hp, so 31.5 * 10 = 315hp support at 10.5:1AFR and 30lb inj's.

Your situation makes sense, 30lb injs are too small for 300whp support without an FMU.

52lb inj's will run fine with MS. The Subaru guys run 100lb inj's in a 2.5l engine and 25psi of boost creating 450whp, and idle is perfect. 52lb'rs are not to big if your ECU can control it properly, and the MS can!!!

Oh, are you SURE PVC will hold up to the heat the exhaust manifold throws off since your intake pipe is like 1" away from it??? The manifold will throw out ~1000F at boost. Your sure about this!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

RussC

RussC

Thanks for the calculations, I really need to get bigger injectors.

Anyone know how much Fuel the stock fuel pump can flow before it dies?

And that black plastic is ABS plastic(used for sewer lines,f1 intakes...), WAY stronger than PVC, and it handles heat real well, not 900-1000f heat though. I made a thin Couple layer foil heatsheild where it gets within 1 inch of touching the manifold.

After several hours of driving, it has slightly deformed it rite at that point, So im going to make a Thicker sheetmetal heatsheild for it. The rest of the ABS (more than 2" away from manifold) is 100% perfect.

just get some metal pipes welded up at a local shop.....

Yellow2 wrote:just get some metal pipes welded up at a local shop.....

Agreed. Instead of making a different heat shield, it shouldn't cost too much to make up piping out of metal. You could probably even do it without welding by buying the correct mandrel bent elbows and connectors.

I will end up with mandrel bent aluminum, but I have very little money, and all my money as of now is going to Injectors, then Water/Air Intercooler, then when thats finalized, ill get some custom charge pipes.

I built that with things I already had.

Rite now thats really not the problem, just a "not-enough-fuel" problem.

I have had good luck with injectors from Deatsch Werks. I have a set of 740cc/min injectors from them in my Nissan and they work great. While they dont list them on their site they can get you Bosch injectors in high impedence in whatever flow rate you need. This is where I'll be buying mine from when Im at that point. When I checked a month ago it was around $200 for a set of 6 42lb injectors, but I am know thinking of also going the 50+lb/hr route as MS should have no issue with them and want room to expand down the road.

I think Im in the same boat with wanting more room to expand injector wise,

Thanks alot for the info! ill check them out.

A friend over here has a intercooled m30 turbo and his 30lb injectors have seen 85% PWM @ only 5.5psi @ 12.9-1 AFR.

This is on the stock pressure so a slight increase will help counquer 10psi. He's also fitted a walboro 255 pump so can run the higher pressure without worry.

I run 42lb injectors myself and have no issues with the idle at all, MS can cope very well and I hear MS2 even more so.

Get intercooled too asap, volvo's have large cheap ones

HTH, Mark.

Max pressure on a stock pump I've seen is 4.5bar but it didn't last very long