XPT

It's far too lean under boost, I'd be aiming for mid 11s under boost. It comes on around 1600rpm and you're in the 13s somewhere then getting leaner again into 14s . Wow no wonder it pinged

What fuel were you using? What were your afrs?

What's your ring end gap? Did you open it up from standard to accommodate boost?

Nah not really, there's probably more dignified ways to go. It was more making the point that the way certain people are carrying on (not you btw) kinda makes me uninspired about mucking around with crossflows.

All this nasty talk makes me want a 253

A bit of a strange problem. My (manual) AU ute misses under load mainly when it's warm. It usually runs ok in the morning, you can give it full throttle and it pulls cleanly through the gear. Sometimes it runs like shit from the getgo, this morning it ran perfectly. At times it can run fine initially then after 15-20 minutes of driving it start playing up again. It doesn't miss at idle, or under light throttle. When it's playing up and you apply say 1/4 throttle or less it pulls through the gear ok. I've replaced the leads with genuine bosch ones still the same symptoms. I know coil packs are a very common problem but I would have thought they're either fucked or not, not intermittent. They're not expensive, I just dont want to get under a car I don't particularly like to do a shit job only to not fix the problem. Ideas anyone?

It might only manage a clutch burnout

Yep it was the coil pack. Thanks for the tip Thom it was piss easy to do it from the top using a few extensions and removing the airbox apart from constantly burning myself on the coolant pipe lol. I had to get it done before it started pissing down. So no time to let it cool. Thanks a lot for your input guys. Cheers

I forgot to say I did the plugs when I got it. I think I've only done about 8k in it. I've run it on e10 or 98, still plays up. It's definitely only on one or two cylinders. At $100 I'll just do the coil packs. It's more the annoyance of having to do it than anything. Just wanted check around the traps to see if there's any other ideas. Thanks for the input guys, I'll let you know how it goes.

I bet it went hard lol. Luckily most cars were tuned rich back then. I've never heard of that sort of BCD. I was thinking more the type that clamps the map /afm at the highest voltage/load point that the ecu can read. Eg clamping the map signal at 5V

That would be heaps of fun in a Corty, I believe the only limiting factor would be the ability to read boost pressure above 10psi with el ecu and tmap. You could run a boost cut defender and a rising rate regulator to maintain afrs but lose ability to retard ignition vs boost beyond that load point.

Well there you go. Yep, it's a lot easier to have one ecu to tune and add corrections for temp and atmospheric conditions etc. Spool imports do H beam 200 rod and forged piston packages with either Ross or CP pistons, $1800 and $2200 respectively. With only moderate power goals and low revs a set of prepped stock 250 rods with ARPs and a set of hypereutectics like Hypatec should be fine.

Yeah I don't think Microtech even make a fuel only ecu anymore. The LT10-C has 4 ignition and 4 injector outputs. So 1 ignition output used and 3 injector outputs running pairs in group fire. The only problem with this is that you can only run high impedance injectors if paired on one driver which limits you if you're going for big power with e85 etc. I think the biggest high impedance injectors you can get are Siemens deka 80lb(875cc) injectors.

He's running a Microtech, so that will take care of ignition timing and rev limiting. The 6A is just there for cdi so a 6AL or 6AL programmable aren't needed.

So I would go a gt3582r 1.06ar turbine housing BA-BF spec with an internal gate as they are T3 flanged and great match for a 250. There's a mob in QLD who do good quality turbos at a reasonable price called Proboost. They're a lot cheaper than a garrett bit still good quality, they have quite a few fast cars running their turbos, check them out on FB https://www.facebook.com/proboostperformanceparts/. The reason I ask about the dump pipe is that you can get them in XR6 5 bolt internal gate, 4 bolt and V band (for external gate) So I guess you're going a TFI dizzy, I'd also run a MSD 6A or another quality cdi to avoid ignition breakdown under boost.

What size flange is the turbo manifold? What sort of flange on the dump pipe?Are you still running a dizzy?

Shit, at first glance I thought the econoguage was a tacho. 6K from cold lol

I'd just be done with it and replace the stock one with a Walbro 255. They're cheap and will have lots of headroom for more future mods.

Do turbocharge it. Don't run a HV oil pump, Ando will spontaneously combust.

If you think you can make one, then you just need to start with a flange like this

That's an aftermarket divorced dump pipe- the turbine and wastegate gasses are completely divided and have their own pipes. The factory dump pipe is cast iron. That one there would be worth a look because even if it didn't quite fit, a bit of cutting, grinding and welding would sort it out.

Can you put up a pic of the back of the turbine housing? If you have a straight copy of the Garrett XR6T gt3582r, the turbine housing should have the wastegate flap incorporated into the housing. Ideally you don't want the wastegate gasses going into a flat plate and squeezing out. You would want an open flange that has a section of pipe allowing the wastegate gasses to merge with the turbine gasses more smoothly or a divorced dump pipe. Like this :

For a 4 litre turbo 3" would be bare minimum. 3.5 - 4" even better

Turbo gas setups are quite specialised and the initial outlay for the components alone is quite expensive. If you already have factory efi, a turbo efi setup is cost effective, quite easy to put together and it's easy to find a tuner.

It's hard to say, if it's a decent Chinese copy with the same wheel sizes as the Garrett gt3582r, it should be reasonably close in spool time. I kind of like having a bit of rev range above idle to putt around off boost when you aren't giving it stick. Given that you have 250 cubes of goodness pushing you around, off boost performance is good and can spool even quite a large turbo without too much lag. Spooling up a GT3582R with the largest 1.06ar housing isn't a problem. Ford went with the 1.06 on the BA-BF XR6T and they come on boost in the low 2000RPM range from memory which is ideal for me even with the smaller rev range of the xflow. Going smaller on the turbine housing would bring the boost threshold lower (when it comes on boost) and choke top end power.