Daves Compound Twin turbo XUD

[Dave]

Hopefully this will be a £25 fix! Just annoying pulling everything apart, after it was all going so well!

[Dave]

She passed her MOT with flying colours - 2 advisories on a cracked wingmirror which will be a temporary permanent issue, and a severely knakkered TRE.

The vnt does not seem oil when the vanes are wide open, so all control is disconnected at the moment, and the big blower just left to spool when it wants... damn its laggy! 5k and you're just about starting + mani pressure :p

When the vnt WAS working, it was moving well at 15psi and was spooled by 3k, big blower doing all the work, silly low EMP, moved and revved really freely.. will get back to this stage soon, and add another 30psi in the loop.

Not much in terms of pics and what not, been busy with gf/family to tune it/fix it lol, but I have loved the reliability of it havent had to open the bonnet since the vnt issue. Considering the amount of extra pipes/fittings there hasnt been a single bit of weeping.

[ozonehostile]

good to hear it dude, il be putting my new creation in for mot next month, did the garage know you or gave them the surprise of testing a twin turbo 306?

[Dave]

Haha yeh they did bring some chaps out the office to look at it, hadnt seen that before

[cwspellowe]

Haha yeh they did bring some chaps out the office to look at it, hadnt seen that before

Trust me, those moments make it one of the more memorable dates in the year

[Dave]

Im just loving it at the moment, it seems to just work as it should.... I've had SO many issues with it before, but all the bushings, stereo, electronics, dash, suspension, brakes all work exactly how they should- including the engine. Its clean inside and polished out, my girlfriend DOESN'T mind getting into it, and its an absolute blast to drive with 6 gears, even if you do only have 64hp until 5k. Im in love again, and it reminds me why I love the 306 so much. I thought the unsprung paddle clutch would be a nightmare, i've done nearly 1k in it, and I cant tell any difference between the stock cluch apart from a little more bite?? The gearbox mounted turbo hasnt caused ANY issues at all, considering some custom stuff went on, and the heat/gear linkages/downpipe/intercooler piping.

So yeh, much love for the 306 again.

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Not to mention, i've had issues with pumps cutting out after high rpm, this one starts better than any engine i've ever used before!

[samass]

Pretty much the feeling I get when I drove mine and can't believe the bitch is still running!

[cwspellowe]

Pretty much the feeling I get when I drove mine and can't believe the bitch is still running!

^^this. Touch wood, i think it may even make it to FCS this year..

[Dave]

Im just utterly over the moon, as some of you have seen my car before, its an absolute STATE most of the time, not starting right, horrendous misfire, thick veg stains down the side, complete and utter skip inside, and just generally untidy horrible suspension issues/handling. its just all been totally cleaned up now... all gone

[Piggy]

cool...well done...need to reread this when I have painkillers ready for the headache I will have!

[Dave]

why will you have a headache?

[Piggy]

all this compound turbo stuff!!!

[silverzx]

Good effort man!

Was it worth going VNT route?

Would of thought a GT-S and a massive HX or something would of been slightly less pain with lots of gain still?

[darrenjlobb]

Was it worth going VNT route?

Its always worth going VNT! You will never look back !

[ginge191]

Good to see this running; all i remember last year was you under the bonnet changing injectors

Lets hope it makes it!

[Poodle]

Congratulations on the mot dude, is it a 4-paddle unsprung clutch you're running on this..?

[zx_volcane]

Nice to know it flew through the MOT, just have to build up the energy now to strip the vnt off and get her boosting again.

45psi will be so full of win!

[Jtrigga]

Really happy to see it running well for you, love that feeling of thinking this is why I drive a 306

[Matt]

Reading this has given me a lot of info! Cheers, compound sounds awesome. Wish I had the knowledge to do something like this!

Top work man!

[Dave]

Right I know this thread is failing hard right now with the lack of videos/pictures, but its partly for my personal reflection aswell, it was going stinking quick today! Even just off the big blower, she was pulling HARD top end, and I cant believe the response on just the big blower through the gears! (I have basically no vnt at the moment).

I took my mother to the swimming pool, and scared her shitless accross the countryside haha, it was so good to drive singing up at 5k.

[Dave]

Still haven't fixed this damn oil seal leak, so its blueing all over the shop when you're idling, but anyway managed to get this video.

It sits so nicely at 5.5k, no nonsense from the turbo just does its thing so relaxed. I cant beleive how responsive it is with the VNT, and how quickly the big blower spools compared to just the single big blower on its own. This is with no MBC, so boosting at 15lb when the vnt naturally opens, with the big blower *taking over* so to speak once its spooled, which is almost as soon as the vnt has spooled. As soon as I can get a decent boost control setup this will hopefully double to 30psi as a starting point.

I've a feeling that I'm gonna need to modify the pump to suite 5.5k driving + though, as this just has all the air you need, and without the fuel to suite up there where theres lots of power potential. So two routes from here, fix the seal, then 1) get it boosting heavy and 2) sort the pump to fuel high. Be onto a winnar then

[Jimbo]

Just out of interest Whats the reason for still running a TMIC on this?

[n0v0s]

Just out of interest Whats the reason for still running a TMIC on this?

'Cause Dave's a boss.

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Still haven't fixed this damn oil seal leak, so its blueing all over the shop when you're idling, but anyway managed to get this video.

It sits so nicely at 5.5k, no nonsense from the turbo just does its thing so relaxed. I cant beleive how responsive it is with the VNT, and how quickly the big blower spools compared to just the single big blower on its own. This is with no MBC, so boosting at 15lb when the vnt naturally opens, with the big blower *taking over* so to speak once its spooled, which is almost as soon as the vnt has spooled. As soon as I can get a decent boost control setup this will hopefully double to 30psi as a starting point.

I've a feeling that I'm gonna need to modify the pump to suite 5.5k driving + though, as this just has all the air you need, and without the fuel to suite up there where theres lots of power potential. So two routes from here, fix the seal, then 1) get it boosting heavy and 2) sort the pump to fuel high. Be onto a winnar then

You've come a long way mate, such awesome potential! Cant wait to see this wound up and go fkin nuts!!

I sincerely hope it doesnt man, but if it goes tits up and explodes, I want to see the head literally blow out through the engine bay under ridiculous boost.

[Frosty]

Just out of interest Whats the reason for still running a TMIC on this?

I wondered this as well. Just out of interest

[Dave]

Cheers, n0v0s, I think it has come a way since beginning, I'm sure we'll meet one day and there will be an XUD orgy bahah, or i'll stick a rod though my block and into my chest, and you'll be the one removing it

Im sticking with TMIC, because A) its not TOTALLY necessary for a FMIC, obviously its useful but if you use big enough blowers then they are efficient enough - dare I say it, this runs cooler now than a stock turbo pushing 15-18psi. and B) its sleeper style and C) it was relatively easy to add additions to the plumbing of the VNT that was already down the back, just added some more exhaust bents and some brackets, and some silicone to the compressor of the VNT; this has also made air filter fitting hellish easy hehe

This to OTT??

[Piggy]

im not tech on twin compound bla bla bla...

but seeing the recent 'post your map' thread, there was the same car, lots of tuning, only difference being a fmic, and the map was quite different with a higher torque figure

[vlj]

im not tech on twin compound bla bla bla...

but seeing the recent 'post your map' thread, there was the same car, lots of tuning, only difference being a fmic, and the map was quite different with a higher torque figure

I think he just means that the FMIC isn't overly necessary, yes it will make power power because of placement lack of heat soak etc - but it's not vital to perform the job.
Could be massively wrong here.

Car looks great Dave

[Sambarker]

im not tech on twin compound bla bla bla...

but seeing the recent 'post your map' thread, there was the same car, lots of tuning, only difference being a fmic, and the map was quite different with a higher torque figure

Twin compound? Wouldn't that be 4 turbos? Now there's a challenge

[Piggy]

should have been a comma....soz...but yes, twin compound ftw

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FMIC makes it a lot more efficient too surely?! Thus giving better results for all your hard work!

[Dave]

Fmic only removes heat thats created through compressor charge, of your not creating the compressor charge in the first place then its not essential. Ideally a fmic would be better but in my application and need to get it on the road it was far easier to leave it top mount.