1988 305 Blown DW8 Project

[darrenjlobb]

Evening,

I figured given I havent done much to the 'bus in quite some time I would post up a thread on the Daily Driver as likely interesting to some

Anyone familier with the forum etc will recognise the car as being Sam Barkers old 305...The one that we and several other Dervheads on this forum have done a few euro trips in over the last couple years, including a trip to Croatia last year, which was a laugh as always and a testament to the car!

So as most will know the car used to have a stage 2/3 DW10 HDI lump in it, making some pretty good power (very good for the 305!!), however this has gone now as Sam has plans for this in bigger and better things So when the HDI was removed, a DW8/gti6 box was dropped in as an engine to make it run, although never got fully fitted / finished.

So I decided given it was to be the daily driver, and hopefully ran alongside the 'bus if/when I get it back on the road...So main aim was needed to be cheap to insure etc, being a GLD model from factory, It was a NAD from factory, so decided to leave it nad, albeit DW8 based...Likely everyone thinking I must be mad, but this is the way it is to be...for now anyway...

So here she be, after a quick cleanup:




First project was to get shafts / exhaust / wiring and plumbing sorted out, so that the car would actually start and drive, I had a week to basically get the car on the road before the insurance / tax ran out on the current daily, so was pushing on fair... Once that was sorted, decided to fit a VE as NAD or not, it was fairly obvious it wouldn't be staying entirely stock, so figured getting a VE on it from the word go would be a good starting point..

So ripped off the lucas / bracket etc, and eyed up the situation!



The DW8 shares the same block bolt pattern as the DW10, which means a stock XUD9 style pump bracket wont bolt up, but will with some modifications, just so happens I still had the one I used on my 16v MTDI project, so saved myself that little job and bolted that right up:



Bolted up a NAD pump (few mods of course), this entaled quite alot of cutting / grinding to get clearance, but mounted all the same..




So got it all back together / few other bits and bobs tidied up and sorted out, and I was on the road, which worked out to be perfect timing....

So anyway, in true fashion, I decided it was obviously necessary to get a baseline dyno run on the thing, so strapped her down, and let her rip!! All of the vacuum at the manifold!!



And of course...the almighty figures / graph!:



So a couple days went on, few more minor problems occurring with brakes etc, but nothing that couldn't be ironed out fairly easily...but I dont think it was more than about 48 hours before I decided something had to be done about the "output" "issues" of the NAD...I also had a spare blower kicking about that didn't really have a home every since I decided to stop running them on my 'bus...so put the two and tow together, and we had a fairly inevitable problem...



So basically in the course of an evening last week, I made up a couple flanges to bolt up to the charger, and some mounting brackets, and before I hardly even realised it had happened, there was an Eaton bolted to the side of the block (what a shame ?!)..So after another hour or two the next day sorting out the belt / pulley situation and connecting up a very crude boost pipe setup, we officially had positive manifold pressure!  Albeit, totally un-intercooled at this stage.

Because I had sold all my charger / big pulley kit back along, this unit is just running at stock crank pulley speeds, which results in it spinning at just 40% of the speed it used to run on the dervbus, however after some quick calculations decided this was likely a good thing, or at least a good thing for the immediate future of a bone stock DW8 bottom end anyway! Should run around 4-5psi, which should be more than enough to give this little nad the extra little shove along it needs...



So obviously, before hitting the road another dyno run was required, so dropped back on the dyno, warmed her up and unleashed her once again///



Quite a nice little increase, and almost exactly the power output we were hoping for, with some intercooling / pump fettling should be up a bit more again...

A graph showing NAD vs Charged:



I must admit, given the fact its still just a 90ish hp machine, it really has made all the difference, car is such a laugh to drive now, peak power being just up near 5k, and pretty linear on its way there, made me giggle anyway given the situation!

Also then swapped out the steering rack, which has been a bit of an ongoing issues ever since a few "issues" in Austria last year:







Thanks for reading

[Niall]

Awesome!!

[zx_volcane]

Hah, 'i was just carrying an eaton round the workshop when suddenly I slipped and it fell onto the engine'

No fear here, dw8 + boost - this is going to be a fun project!

[Piggy]

So epic.
Made my day this making that extra 1bhp

[Dum-Dum]

I heard rumors of this yesterday but it looks so much cooler in the photos.

That is a phenomenal gain for '4-5psi' almost 50% improvement and it makes such beautiful power and torque curves.

[darrenjlobb]

The boost is fairly linear, should have plotted on the graphs but didnt, hits a peak of 5psi at 5k.... Hoot to drive with the 6 box

[Niall]

by the way I've just noticed the wall of boost. Who's at the top then?

[darrenjlobb]

Horton heads up the -Blown department at the moment....and Fooby is just hanging in there in the -NA leaderboard!!

Feel free to challenge!! Although you have boost so cant beat Fooby!!

[Piggy]

Was so fun
...adjust.
Waaahaaay an extra .7bhp!

[Niall]

My car isn't going anywhere near a dyno until its fixed but i will happily bring it down once fixed for a bit of fettling

[bashbarnard]

Love it. It was clearly to convenient to not drop a charger on it. Love the motor also.

[Jonny81191]

I'll knock fooby off the top with my s16

Also loving the charger lash up on there, looks like a good curve. What was the target figure?

[darrenjlobb]

Haha, tbh we were aiming for stock xud9 power, so only 1-2hp short! I wreckon with intercooling it would be there.... only makes 4-5psi due to gearing, but its more than enough, drives really really well tbh.

Have got some videos of it but will take ages to upload!

[daniel909]

Following this car up the road sound epic :

While we are on topic of the 305 please can you tell me and everyone what going on here please darren 
   

[HDIkyle]

When did Sam sell this? And why? Only followed it other week on the trailer

[darrenjlobb]

https://youtu.be/89dZqpWx6qs?t=3m11s

[Dum-Dum]

0:47 "It kinda makes sense to leave it as a NAD"
0:59 "I thought it might be a bit boring leaving it alone"
1:02 "I've got a random M62 supercharger lying around"

15 seconds right there, decision was made to boost it.

[bashbarnard]

The thing that makes this low power build amazing to me is the fact it was somehow easier to supercharge a nad lump rather than put an xud9 in it! I mean. Why not right

[Piggy]

Still amazes me... 5psi on a dw8 makes same power as 14psi on a xud9

I mean... It's going to go bang... But still amazing

[darrenjlobb]

Still amazes me... 5psi on a dw8 makes same power as 14psi on a xud9

I mean... It's going to go bang... But still amazing

XUD9 would make more than 90hp at 14psi though if you gave it fuel and more rpms...This is also higher compression which will help.

[Piggy]

Yeah I knows... I mean it's not like that was standard fueling from a nad pump
Still pretty ace

[205dtub]

Awesome and hilarious! Love the accidental supercharging description.

[welshpug]

certainly proves that boost figures are not the full story, ever, its also the amount of air shifted.

[Ruan]

certainly proves that boost figures are not the full story, ever, its also the amount of air shifted.

For a given cylinder head, the boost figures _do_ give a good idea (as long as the compressor isn't being run way outside of it's efficiency) - difference being you couldn't take this up the side of a mountain on a hot day and expect it to provide the same emissions results and produce the same power!

On a cool day at sea level, an XUD9TE would also make 90hp at 5psi boost - but obviously wouldn't still do this up a mountain on a red hot day.

[Stef205]

Nice work darren! Nice to see even on a diesel you still get the supercharger curve. Only down side to those merc m62's is the pulley limitations.

[darrenjlobb]

Nice work darren! Nice to see even on a diesel you still get the supercharger curve. Only down side to those merc m62's is the pulley limitations.

Yeah, the ratios are pants using stock pulleys, but given the stock motor the extra low boost is ideal really, if it was on the bus it would be geared up, but given its not, its cheap and cheerfull, back to my roots project in some respects, quite enjoyed doing it tbh!

[Matt]

Awesome little project! I agree with the above, love how it's the go to to drop a charger in rather than swap the engine out

Some neat curves you got there, looks like a solid delivery. Bet it's amazing on the back roads!