B-Man's Excellent Engine Adventures

[B-Man]

Bloody Hell,

I just spent the day pullling bits off my engine - aiming to get the head off so I can assess the damage of a few months back. I didn't get as far as the head, but I got a fair way through.

I got the Plenum off - I wanted to understand what was inside the Hills custom plenum - nothing really interesting. Here's a few pics :

I also got the injectors and rails out - Does anyone know if they can hi-flo injectors when they are still on the rails ? Unfortunately it looks like the rail has been resting on the injectors as the little platic bit on the base of the injectors is broken on most of them - See what I mean ?

So after all my hard work, I have a bloody sore back , flithy fingernails and a shirt I can't wear again - Oh, well time for a beer:

I got the intake manifold off, but I can't see how you can get the turbo off - there are 4 bolts and 2 nuts on the dump pipe - to get at them is very awkward. And the bolts that old the turbo on to the exhast manifold are as tight as a nun. I don't want to bust anything so I have been real careful - What's the trick to getting the turbo off ???

More pics here:

http://brf.homelinux.com/images/engine/index.html

Anyone that know's what they are doing want to come around next weekend and help pull the rest of it down ? There are beers in it for ya !!

Stay tuned for the next installment of B-Man's excellent engine adventures........

[GTS20X]

MMMM, beers for helping to pull an engine down, sounds tempting.

[Steve]

B-man, dont see how they could be high flowed in the rail. Those holes look a bit larger than the holes in the bottom of the stock injector - bit wierd that all those platic bits are broken. I have been told that they are pretty cheap to replace, but good luck getting the injectors out of the rail.

The plenum isnt too much to look at is it. On the inside, you can see that they have radiused the top of the runners, but I definately expected better from them. They promised me bellmouthed runners, but didnt deliver that - as the old saying goes, 'buyer beware'.

[Clint32]

The plenum is Ok, but deffinately not as good as others, what do they sell for?

[Steve]

Slugged me $895 with a second hand ford throttle body - then I had to post it back (at my expense) as they had put the wrong flange on it for the ford throttle body and the arm for the throttle cable was in the wrong spot.

When I got the plenum back (2 days later than they PROMISED), they had completely removed the arm for the throttle body so I had to get another welded on. Also the TPS was still the ford one, and had to be made to adapt up to the skyline one. They also said they were sorry but they had run out of studs to secure the plenum, and I could just drill those holes out. Also, the plenum needed to be refaced, as they had just used an oilstone after the final welding, and to quote 'its close enough'. I must be fussy, I didnt want close enough, I wanted 'as exact as possible'.

Very, very unprofessional IMHO - /rant

[B-Man]

B-man, dont see how they could be high flowed in the rail.

Me either - the reason I said that was because I tried getting the caps of the top of the injectors - again the screws were as tight as a nun - It didn't look like they had been taking off before as even my good phillips head made a bit of a bur on the heads of the screw - I even stripped one (I'll let the injector guys take that one out) - And the scress looked brand new when I took off the rail.

bit wierd that all those platic bits are broken

Yeah it is a bit - since I payed for new injectors.

They promised me bellmouthed runners, but didnt deliver that

Me too - I asked what was in-side the plenum and they said that it was specially made up with bellmouth stuff. They wouldn't go into details as it was "intelectual property".

[Steve]

Oh, and they wanted the top of my plenum back PLUS my throttle body and throttle cable.

[B-Man]

I didn't get a Throttle Position Sensor with the plenum - maybe because the 'package' included an EMS ECU ?

Now I am going back to a Power FC, I spose I'll have to get a new TPS too -

[2rismo]

What a crock of teh proverbial.... Absolute P.O.S. guys....

Honestly cannot beleive the price you've both copped for this level of workmanship!?!?!?!

Not a shot at you guys but JEEEZZZZ!!!!! Even looks shoddy...

Adrian

[Steve]

2rsimo, I can only agree 100%.

I was extremely disappointed. I was not sent what I was promised - not by a long shot. I bought the plenum because alot of guys had good things to say about the manufacturer, and when I enquired he promised the 'flows 95cfm per runner over stock, bellmouthed and radiused, flow tested even flow on all runners'

I am somewhat sceptical about all claims now. As soon as I can find the money, I will be upgrading.

Hopefully anybody dealing with them in the future will take something away from this thread, and perhaps not have the wool pulled over their eyes too.

Bottom line, make sure you get all promises in writing.

[Warpspeed]

Flows 95 cfm over stock eh !

I would like to see that. A bog stock bare head flows about 94 CFM at 28 inches of water, so adding this trick plenum doubles cylinder head airflow. Ha ha ha.

Yeah, in your dreams only I am afraid. I bet these clowns do not even posses an airflow bench.

[2rismo]

prob @ 10 inches and cheating.... lol

Adrian

[Guest generic r33]

what is a plenum??

pls?

[B-Man]

Plenum - "A condition, space, or enclosure in which air or other gas is at a pressure greater than that of the outside atmosphere."

ie The first pic in the above post.

It's the bit that the compressed air goes in after the turbo & intercooler but before the inlet manifold and head. The thing that looks like a funny looking clam shell on the top of your engine.

[rb25]

That is the shittest plenum ive seen for ages. sorry to hear you got ripped off man....

By the look/sounds of it, Hills "intelectual property" and business conduct isnt worth shit to anyone.

[sidewaymambo]

Plenum? what plenum?

Originally posted by rb25

That is the shittest plenum ive seen for ages. sorry to hear you got ripped off man....

By the look/sounds of it, Hills "intelectual property" and business conduct isnt worth shit to anyone.

[Guest INASNT]

Originally posted by rb25

That is the shittest plenum ive seen for ages. sorry to hear you got ripped off man....

By the look/sounds of it, Hills "intelectual property" and business conduct isnt worth shit to anyone.

even their equal length runner exhaust manifold AINT even close to being equal lenght!!

[JimX]

What exactly is bad about this plenum? I'm not an expert on air flow but just looking at it it doesn't seem too bad.

B-Man, if you are still having problems getting the turbo off, have a read of this thread

If you can't get the exhaust nuts off, you might have to spray them with WD40 or something and let sit overnight. Don't be surprised if you end up snapping one or more studs off though, it is a common thing to happen on exhaust manifolds. Just be prepared for it. I was lucky with mine, the nuts on mine were actually not tight at all and came off easily. The oil and coolant lines were pretty tight, especially given the awkward positioning of them.

[B-Man]

Hey Jim,

Thanks for the tip - I can't start my engine , so I might have to get the blowtorch out to heat it up a bit - I must remember to block the fuel lines off before I do that though

I won't be snapping any heads off though - I'm being ultra carefull with this process.

Re: Plenum - I'm no expert either, but from what I understand after doing some research (hindsight) - it is a very very complex art mixed with theory.

Apparently - plenum and intake dynamics are all about velocity, not so much volume.

Apparently, It's easy to slow the velocity of air - Very hard to speed it up. Hence tapered ram tubes with bellmouth ends.

To get velocity, you need distance so shortening the distance decreases velocity - Add a ram effect and you get a bit more velocity. If you increase diameters of stuff, you decrease the velocity.

I went to see a guy that was developing a new kind of RB plenum....

I spent 30 mins with this guy on the phone and 30 mins at his workshop - Nice guy - very helpful. Small workshop - Seperate machining room. Very much a custom perfectionist kind of guy - Easily distracted and very theortetical. Has a RB25 head and RB26 head there

His design principal is based on the tried & tested N/A method of tuned length ram tubes with bellmouthed ends, the tubes are tapered with sharp ends at the head - He reckons that Nissan got it all wrong with the head design :gofigure: . But what he said all made sense. (caviat: to me )

He doesn't use any of the standard inlet manifold, runners, etc - it's a complete fabrication from scratch - Must take him ages to put together. The bellmouth ends are enclosed in a cylinder plenum. A fuel rail for top feed injectors in included as is the water junction and all the idle controll stuff for the air con.

He reckons that it's all about the velocity of enough the air into the head - not so much the volume & pressure. He actually blanks off part of the intake port on the head to allow his narrow end ram tubes to do their bit - imagine a circle (the intake port on the head) then put a rectangle inside the circle - that how much he blanks off - He says it scares people of - but is just not required. Go figure. He says that the standard throttle body is plenty big enough , no need to change it. He reckons he has done the math (way beyond my small brain capacity)

In his design the throttle body mounts to the plenum from underneath. Go figure again ?? I wonder how the throttle cable will work.

He seems to know his stuff and I will definitely go back there to see the results of his first one - He's doing a before and after dyno run without changing anything else but the plenum and hopes to get 50HP more.

His design reminds me of the good ol days when a fuel injected big block had 8 massive ram tubes sticking out the bonnet - then imagine a plenum on the top, enclosing the 8 bellmouth ends, with forced air pressurising the plenum.

I think I'll get a GReddy Plenum/intake...........

[sidewaymambo]

Originally posted by B-Man

..............................

I think I'll get a GReddy Plenum/intake...........

good say....I felt same way..

do this ages ago, it might save one engine..