Mint VP V6 Sedan soon to be boosted!

[Holden202T]

well its alive

spent a few hours last night getting the last bits sorted and fired her up, all testing seemed to work ok so we had some late dinner than went for a spin up the road, I wasn't too worried about the motor more so the T700 that I pretty much fully dis-assembled then re-assembled with new clutches and such, but it so far seems to be doing everything right! shifts very firm and even chirped into 2nd gear, its never done that before and that was off boost too! so first few dabs of the throttle were soft just to get it into low boost and see how it went on the wideband, all looked good, 2 psi and its starting to go richer than commanded so I figured we had it on the safe side and even 2psi felt better than previously!

time to give it a bit more, and so the brother pulls out of an intersection and laid the boot in and at 3.5 psi it blew the intercooler pipe off!! quick check on the side of the road and it looks like he did up every clamp except that one! so im thinking previous runs it was probably bleeding a fair bit of boost out the hose anyways, and it looked like it was boosting later than it used to.

so we limped it back home and by this time it was 9:30 and I still had a 1.5hr drive ahead of me, so we called it a night.

only issue we found is there is some oil coming out around the inspection cover, so we'll need to check that, its got a second hand cam plug in it and also there was some issues when my brother installed the rear main (lip folded over) so maybe one of these two are causing the leak, wont know for sure till we get under it.

either way it looks like its going to have plenty of potential!! and considering what's been done I'm very happy to only have a small oil leak

[Holden202T]

so we've had a bit of a rocky road getting this thing working.

after putting the cooler pipe back on and going for another test drive, its really not made any difference to boost, just didn't blow the pipe off this time! so we started working on where the boost was bleeding ....

we screwed the wastegate screw in which normally gives a 2psi ish increase, there was barely half a psi change from this, so we thought there has to be something else causing the issues.

so we decided an easy test was to remove the intercooler and run the turbo straight into the motor like it was before... instant 15psi and subsequently now hard to test due to traction issues whenever he tries to feed it on

so good and bad result, need to check all the cooler piping for cracks in the bends etc, failing that pressure test the cooler!

so its looking promising for HP and once the cooler issues are resolved its going to be on the home stretch!

[VL400]

My vote is on the missing rag

[immortality]

My vote is on the missing rag

My first thought was a partially blocked cooler core, a rag would definitely do that.

[Holden202T]

It's more like a split in a pipe though, gets to a certain psi to push the hole open then never increases from there!!!

Ultimately a rag would kick ass heheheh

[Holden202T]

so we took this thing out to Gunnedah drags on the weekend! was its first real outing other than a few test runs at home around the block etc.

it managed a best of 9.004 over the 1/8th ... I think my brother was a bit disappointed but it also puts it into perspective just what it takes to get a reasonable time!

its not making boost off the line so that's hurting a lot so is the 3.08 diff and 1300kg odd weight to move! it still reeled in a VE R8 Clubsport once it got going so its definitely going ok for what it is hehe!

we need to work out a few issues and I think theres talk of diff gears and a spool for the next event so a work in progress

[Holden202T]

so been a long time with this one, he changed the diff and got a B&M shifter for it, and went back to Gunnedah, in the end he only got two runs in and muffed gear changes and such.... long story short, he hit the rev limiter a few times on boost and it also over boosted before Gunnedah, and also was just going lean at the end of the revs (fuel system limiting I believe), so I think a combination of things might have caused the issues, its pretty much broken the ring lands of all 6 pistons to some extent, some were just tight in the piston, others had slight cracks in them but the end result was fairly conclusive

the original decision to go for the hypatec pistons was just that it was a massive price difference and he decided to risk it rather than spend the cash on it the first time.

so we've gone with the option of mahle forged pistons from precision, and I must say they are a nice looking piston compared to the cast ones!

one thing I found with the hypatecs is that all the failures were where the split is in the skirt, and the material between the rings is actually narrower than an original piston, so I wanted to make sure the new ones didn't have the split kirt, so rang precision to confirm before we went with them!

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so I've got the pistons and rods all ready to go, I've cc'ed the dish and measured the difference in compression heights, just waiting on the other bits to get prepped then I can start assembling it.

[vlad01]

oh wow! they are nice. They are the alternatives to the ones I bought, but look hell of a lot stronger.

Im NA so I wanted cast. I'll keep those in mind on the next engine one day.

[Holden202T]

yeah hoping on the stronger part hehehe

they certainly look very nice!

[vlad01]

So what CR have they come out to be?