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wdc330i 06-09-2022 12:41 PM

Whoa. Just saw this. What a mess.

John V 07-14-2022 08:27 AM

1 Attachment(s)
The state of my short block for the past two weeks. Rings gapped, cylinders honed, measured and cleaned, bearing clearances measured. Crank, oil pump, rear main seal installed. So basically all of the time-consuming work has been done. It just needs pistons. I've been waiting on them for a month. They were supposed to ship last Friday, but the manufacturer encountered delays in final machining. Now they're supposed to ship (overnight) on Friday, to get to me on Saturday). I'm not holding my breath.

I leave for Toledo on Wednesday, with or without the car.

I'm kind of excited about this engine. It's now an Ecoboost crank (which is forged, 94mm stroke rather than the 100mm stroke of the cast 2.5 crank). Same 89mm bore, so it's now 2.34L, down from 2.49L. Pistons are now 2618 forgings, much stronger than the prior pistons. Upgraded to Ecoboost sodium-filled exhaust valves. It should make as much power as the last one. It might make a little less power from 3500-4500 RPM but I was always limiting boost at low RPM anyway since it would just knock the tires off. The shorter stroke gives me more RPM headroom. Safe upper limit should be 8500 RPM now - don't think I'll ever go there, but being able to routinely spin to 7500-7800 would be really nice.

Also new engine mounts, something I CAD'ed up and bought from SendCutSend.com, then welded up. Much nicer than my old hacked-together tubular mounts.

JV

JST 07-14-2022 08:52 AM

Is the block still a basic 2.5L block? And when you say eco boost, is that the 2.0 or the 2.3?

John V 07-14-2022 09:14 AM

It's a basic 2.5L block.

The 94mm crank is the 2.3L unit.

JST 10-10-2022 10:42 PM

Gordon Murray also apparently enjoys a built Duratec:

https://www.theautopian.com/mclaren-...d-masterpiece/

John V 10-11-2022 07:16 AM

Pretty cool, odd though that he didn't use a VVT head. That's just throwing power away for no good reason.

JST 10-11-2022 07:30 AM

Trying to replicate the peakier power delivery of the original? Idk, that’s the only thing I can think.

John V 10-11-2022 11:37 AM

A lot of people don't run VVT because their engine management solutions can't run it. But when running a factory ECU is so easy, there's really no reason to use anything else for a street car.

Nick M3 10-11-2022 11:54 AM

Quote:

Originally Posted by John V (Post 591179)
A lot of people don't run VVT because their engine management solutions can't run it. But when running a factory ECU is so easy, there's really no reason to use anything else for a street car.

I'm going to guess that it's related to the ITBs and etc.

John V 10-11-2022 07:16 PM

What would itbs have to do with vvt? If anything I'd want vvt more with an ITB motor


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