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I have a bad feeling that my car is knocking way to much. I just installed a nice electronic boost controller (Greddy Profec Type-S) and I set the boost so it wouldn't go over about 10psi (0.69 bar) just to get a feel for how everything is preforming. I ran the car with freescan running as well as my wideband software showing the AFR. She went from ~14 AFR to ~12 AFR under boost and knocked about 15-20 times PER acceleration run. By the end of only a 10 minute drive I had over 120 knock counts! :sick: I am running 93 Octane from the local gas station and my massive chargecooler with large electric pump was running perfect, the chargecooler was ice cold the whole time. Now, I did just reset the computer so is this normal while the Esprit is "learning" or is something else amiss?

Just in case people aren't familiar with my upgrades (that and I keep forgetting to put them in my profile) the car has a Walbro upgraded fuel pump, freshly cleaned and reconditioned tanks, -6 AN lines with RC Injectors and aeromotive FPR, GT3071R turbo, 3" turbo back exhaust, WC Engineering custom Memcal, and adjustable timing gear.

- Graham

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Graham,

This is definitely too much. Usually a good 2,2 litre 4-Cylinder engine will throw a couple (usually 5-10) knocks on startup and maybe one or two on very hard acceleration. Most engines even dont do any knocking when running, just some on startup.

You should investigate this ...

Cheers

Marcus

Marcus

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Thanks Marcus, I feared it was way to high. I am now wondering why its knocking. It certainly doesn't seem to be a lack of fuel or a high MAT so I guess it has to be either poor fuel or an ignition problem.

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93 RON - That sounds like cheap stuff.

Have you tried any proper fuel ? like at least 95 RON. I typically run 97ron and as Marcus says I typically see only a couple of knock counts if any on my runs.

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Remember that the US has the fuel rating (R+M)/2 where as Europe its usually just RON. Thus 93 (R+M)/2 is usually around 95-97 RON. Sorry I should have made it clear that I put in 93 (R+M)/2 :-)

Edited by Drfatz
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Graham,

Loosen your knock sensor, mine was too tight at 16fl/lbs and picked up all kinds of knock much like you are experiencing. I put mine back in a little more than finger tight and seldom picks up a few counts. Your AFR's are a little lean, what plugs are you running? Iridium? If so, switch back to the stock one's, my car knocked like heck with iridiums in there, took em out and knock almost completely went away. Glad to hear you got the boost controller set up, is it holding boost all the way to redline?

Artie

89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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Hi Dermont and Artie thanks for your inputs! I suspect it may be a faulty knock sensor and/or it may be to tight. Also, I am indeed running the NGK Iridium plus. I read a post by you Artie a while ago about the Iridium plugs causing problems. What are the stock plugs make, part #? As for the boost controller it seems to work great, but I still get major boost creep above 5500 rpm. I am going to remove the turbo tonight and see about porting out the wastegate and possibly installing a larger waste valve then I should be able to run solid boost all the way to redline.

I will say this though, when the boost starts to come on she is REALLY fast B)

-Graham

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Change the plugs first before you take the turbo off. The stock plugs are BPR6EKN, a few bucks each at the auto parts store and they have always had them in stock. As for creep, did you turn the gain down on the boost controller? This will give you a method of controlling out the creep to some degree. If the creep is greater than a PSI or 2 then you'll need to port out the wastegate. There is a lot of material left on these hosings for porting, although I know you went with a different turbo, you could always look into an external gate!:whistle: HOw much boost are you running BTW? Dyno soon so I can compare! Is the turbo smooth and linear? When do you make full boost and how does she sound?

Artie

89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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I will pick up a set of those plugs tomorrow! As for the creep, I turned the gain and the low and high boost all the way down AND had the waste gate actuator set to barley holding the wastegate shut. Even with all of that once the car hits about 5800-6000 RPM she can't keep boost below 20 PSI. Right now I plan to run around 20 PSI max once I get the turbo sorted! I actually pulled off the turbo tonight and took a look at the wastegate. The opening is about 25 mm and the puck is about 33.5 mm! So there is a bit to bore out, plus the housing can be opened up a bit to help direct a little more gas into the wastegate. I hope with all of this and the Greddy Type-S I can get her to sustain a solid 20 psi.

Edited by Drfatz
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should be enough to keep the creep down. You may need to restrict the exhaust some too. Make sure when you port the wastegate, that you chamfer the edges on the opening once you cut or port it. If you leave a sharp edge it will crack in no time and then you'll have a nice worthless exhaust housing! :) Not that I know this from experience porting turbo's or anything! :whistle:

89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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Hi,

have you checked fuel pressure? How about your O2 voltage?

RGDS, B

LOTUS Esprit Turbo SE, 1990

P.U.K. racing turbo charger

ECU chip 1.1 bar

Motorsport racing fuel pump

RC racing High Flow secondary injectors

RC racing High Flow primary injectors

custom made titanium free flow exhaust

Electric CC pump

Double size Chargecooler, heavy duty version

Racing air filter

BOV

Crankcase Breather filter

Ram air converison

Uprated Valeo clutch with 25% more torque

KW85 HT leads, IW22 spark plugs

S4S wheels, front mask, rear spoiler

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Graham,

How'd you make out? Any new developments. Interested to see if the change of plugs helped any.

Artie

89 White Esprit SE

...a few little upgrades....

93 RX7.....Silverstone

....slightly modded...Muahaha...

New Addition:

1990 300ZX TT......Hmmm

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