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Those exhaust versus intake manifold pressure levels are pretty unacceptable imho. You'll find at that kind of level your engine VE will be plummeting compared to normal, if it's even sustainable My take away from that is the 7670 is a terrible call for that engine setup - at least at those rpm.

Nismo32ish - because the way the thread convo has panned out I feel compelled to point out that these theoretical numbers AREN'T for E70 like the earlier discussion could lead one to think.

Would the 8374 had been a better choice for my 3.2 build for response , I was looking at the 8374 when I was sourcing parts but was recommended to get the 6262, that turned out to be a 6266. Just wondering, Paul is being a pest,lol

Would the 8374 had been a better choice for my 3.2 build for response , I was looking at the 8374 when I was sourcing parts but was recommended to get the 6262, that turned out to be a 6266. Just wondering, Paul is being a pest,lol

I'd have gone an EFR8374 over a Precision 6266 on your car with what you were after, money being no object. I'm certain it'd be a nicer setup - though I'm not really so sure it'd be worth the money and effort changing now that you have the 6266 - though. Depends on if you still feel it needs more snap? Maybe try and find someone with an EFR on board?

Edited by Lithium

I'd have gone an EFR8374 over a Precision 6266 on your car with what you were after, money being no object. I'm certain it'd be a nicer setup - though I'm not really so sure it'd be worth the money and effort changing now that you have the 6266 - though. Depends on if you still feel it needs more snap? Maybe try and find someone with an EFR on board?

See what I mean about a pest :)

When I said OK to the 6262 it was going on the 2.6 as luck had it they put the 6266 on ?? so I thought I would leave it on and see how it goes with the 3.2 and it is pretty good but the 8374 seems to get going a bit earlier and I would like a bit more snap but happy with the way it goes.

If I ever decided to change the 6266 to a 8374, is there much extra work to fit it on the setup I have now?

Dump pipe won't line up and a slight pipe mod to the pipe that runs from the turbo outlet to the guard.

This is your fault, making me think about another stupid Turbo that probably not worth the exchange for the extra go ?

Hard to find out much about the 2 but there does not seem to be much in it, the 8374 seems to spool a little earlier, but very little from what I could see, but ??

The PT6266 CEA is Gen 2

Edited by Nismo 3.2ish

This is your fault, making me think about another stupid Turbo that probably not worth the exchange for the extra go ?

Hard to find out much about the 2 but there does not seem to be much in it, the 8374 seems to spool a little earlier, but very little from what I could see, but ??

The PT6266 CEA is Gen 2

For what it's worth Pete, just leave it alone and drive it. Honestly.

  • Like 1

For what it's worth Pete, just leave it alone and drive it. Honestly.

This is exactly right. That 6266 makes serious top end (I would think compares better to the air works 8376 s300sxe I posted). Only problem is there isn't s lick of data on precision turbos and I'm a mechanical engineer. I like designing before I commit my money!

Those exhaust versus intake manifold pressure levels are pretty unacceptable imho. You'll find at that kind of level your engine VE will be plummeting compared to normal, if it's even sustainable My take away from that is the 7670 is a terrible call for that engine setup - at least at those rpm.

Nismo32ish - because the way the thread convo has panned out I feel compelled to point out that these theoretical numbers AREN'T for E70 like the earlier discussion could lead one to think.

Totally true!

Didn't want to make TOO many changes. This would be closer to racegas.

FYI I've started working on timing. WOW...BIG changes!

Be prepared for new dyno numbers! Haltech is super conservative! This car just picked up a definite seat of the pants increase at only 2 deg advance...and NO KNOCK.

EDIT - just reviewed log and Fuel pressure is dropping off on top end. I'm betting I've maxed the DW300 pump. It hung in there pretty well...any clue on what -6 AN lines and stock fuel lines will do? Am I limited there as well while I'm making changes?

  • Like 1

I have the Haltech 2500 Elite ECU, having some spiking problems. Went back and had a tune touch up and seemed to fix it but the weather went cold and I am having the same problem @ 4000rpm + after it is on full boost. It spikes and the ECU makes it drop back for a split second and off it goes again. Just needs a touch up again to sort it out , but I was wondering, the HKS evc 6 boost controller was taken off and then the ECU was running the show,

Would the same spiking situation be happening if the HKS boost controller was controlling the boost, I am not changing anything, just wondering ?

I have the Haltech 2500 Elite ECU, having some spiking problems. Went back and had a tune touch up and seemed to fix it but the weather went cold and I am having the same problem @ 4000rpm + after it is on full boost. It spikes and the ECU makes it drop back for a split second and off it goes again. Just needs a touch up again to sort it out , but I was wondering, the HKS evc 6 boost controller was taken off and then the ECU was running the show,

Would the same spiking situation be happening if the HKS boost controller was controlling the boost, I am not changing anything, just wondering ?

ECU should do a better job than the evc. Extreme temperature swings will challenge any system at full boost. Mention it next time you are in the shop but I wouldn't think it justifies a special trip.

ECU should do a better job than the evc. Extreme temperature swings will challenge any system at full boost. Mention it next time you are in the shop but I wouldn't think it justifies a special trip.

This was explained and I do understand.

Just wondering, the adjustments had been made to the tune on a cold day and it was great for a couple of weeks, then the weather started turning cold up here when it started happening again. I usually go early in the morning, at the coldest time of the day, so I waited until 2pm when it was much warmer and ran it again, same thing happens.

This only happens on E85 and it makes 75KW more than 98 pump @ around 4000rpm , could this cause the spike as it wants to keep boosting and the ECU steps in and stops it and brings it back to where the boost should be..

I am not worried, I am with a great shop that looks after their customers, just good to get feedback from blokes that know what they are talking about and you may find it interesting or have had the same experience :/

lower the base duty and let the closed loop do the rest

He is trying to hold the wastegate shut as long as he can to build the boost faster, looks like it has to be less aggressive for the colder weather , boohoo .

Add a trim knob. Not sure how it works on those models but in closed loop on platinum the trim knob can lower the target boost (and resultant tables). In open loop it drops duty cycle by a certain percent.

I am not worried, I am with a great shop that looks after their customers, just good to get feedback from blokes that know what they are talking about and you may find it interesting or have had the same experience :/

How much spike

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