JMC's G60

[boost monkey 0]

I would agree with Kev and Jonathan's theories:

 

When the bonnet is open, intake air is slightly cooler and consequently slightly more dense. This increases the power and torque at low rpms, but as the air has more mass and is colder it flows slower at the top end which results in a dip on both graphs.

 

Bonnet shut is the diametric opposite of this:

 

When the bonnet is shut, intake is slightly hotter and consequently less dense. This reduces the power and torque at low rpms, but as the air has less mass and is warmer it flows faster at the top end which results in a peak (matching and passing the bonnet open plots) on both graphs.

 

My 2p.

 

Jon.

[Kevin Bacon 5]

I think alot of this is academic though - persoanlly I think real driving conditions will be somewhere in between these two sceanrios as there will be a lot more air flow than you get at a dyno.

 

I agree, especially in winter where both air temp and air density are very favourable for forced induction :D

 

When I had my Vortech charger engine on the dyno, we were spraying the charger with water, directing the fan at all sorts of places to try and improve matters, but realistically, it's not the sort of thing you can emulate on the road :lol:

 

I think a well thought out air intake / bonnet vent system would be ideal, plus the shielding you mentioned.

 

It's interesting how the seemingly large diferences on the dyno charts don't really translate into anything significant on the road though. Well, that's what I find at least.

 

Here's an example:-

 

Gallardo LP560 - 1500kg - 552hp, 398lb ft @ 6000rpm

 

997 GT2 - 1440kg - 523hp, 501lb ft @ 2200 - 4500rpm

 

Quite similar on paper, and you'd think the lighter Porsche, with it's 100lb ft advantage would beat the Lambo to 60 and to 100mph but nope, the Lambo wins! That's why I always take dyno plots at face value as it's not a measure of how fast a car is, rather just how much grunt the engine has, but dynos are obviously brilliant for tuning and experimenting, such as you're doing!

[boost monkey 0]

yeah, there's always so many variable to consider :/

 

a CAD designed bonnet vent / bay ventilation / intake system is something I would love to get involved in.

 

Dissertation material perhaps?

[JMC 0]

Interesting results there. Only ever had my car run on rollers with the bonnet up. My car seems to drop around 20bhp at around 6k can only be retard/boost bleed due to knock and is very obvious in the graph. Although on the road I can only reproduce this by doing consecutive QM runs without any normal driving in between. When it happens you can feel the car pull back. I'm sure this is due to the gwerks ss mani heat soaking the head and inlet manifold and happens every time on the RR due to the lack of air suction under the car maybe, next time I'll ask them to do a run with the bonnet down see if it still does it!

 

Could be a faulty ISV I suppose but it's just too consistent.

 

This is a graph I got on greens before I went to reds (reds get me to 6k before it drops) as you can see it drops at 5800rpm or there abouts.

 

Your torque curve with the bonnet up looks very like mine. I would have thought knock was more likely with the bonnet down - isn't it temperature related (more prone at higher temps)? If it's knocking can you get any more fuel in at the top end through tweaking the map - that would help.

[JMC 0]

When you say air box, do you mean the standard one? If so, having the box cut open would draw in more warm air from the bay, wouldn't it? I've seen some people put the air filter behind the liner in the wheel arch, with the pipe to it coming up through the hole where the carbon canister normally sits, do you think moving the air filter down there might help with lower intake air temps. Also, what about using one of those thermal manifold gaskets that stop heat being transferred through from exhaust manifold into the head then from the head into the inlet? I found a company called Ferriday Engineering that do them for around £45 each, for the PD block! :dorky: I mean for the sake of under £100, it must be worth a shot?

 

Is you exhaust manifold heat wrapped as well?

 

Yep, using a standard air box. With a cold air feed coming up through where the carbon canister was and into the bottom of the box (the box has been opened out slightly just to let the air feed in). I've got a picture somewhere in this thread (back around p5 I think).

 

The ss manifold isn't wrapped - G-werks will not honour their warranty if it is wrapped. Basically there are concerns about them getting so hot when wrapped that they fail.

 

I like the idea of the thermal insulator, however my main concern at the back of the bay, is that with or without insulators the air temp through convection will be very high anyway as there is little to promote airflow back there. I've been thinking along the lines of Kev and Jons posts around venting somewhere on the bonnet to get air round the inlet. The water injection should help as well, as will the nitrous if that gets done 8) in fact if I do go nitrous, then I'll need some air flow back there anyway to keep the nozzles as cool as possible.

[mrbeige 0]

The ss manifold isn't wrapped - G-werks will not honour their warranty if it is wrapped. Basically there are concerns about them getting so hot when wrapped that they fail.

 

I like the idea of the thermal insulator, however my main concern at the back of the bay, is that with or without insulators the air temp through convection will be very high anyway as there is little to promote airflow back there. I've been thinking along the lines of Kev and Jons posts around venting somewhere on the bonnet to get air round the inlet.

I think that wrapping the exhaust mani would make a huuuuge difference to under bonnet temps and exhaust scavenging. Indeed, it would further reduce any heat transfer to the inlet manifold. That coupled with thermal insulators could be the way forward. Also, surely the design/manufacture of a performance type modification like an exhaust manifold shouldn't suffer from failure if they are wrapped? Surely from a pure performance angle, wrapping should be encouraged?

[JMC 0]

I think that wrapping the exhaust mani would make a huuuuge difference to under bonnet temps and exhaust scavenging. Indeed, it would further reduce any heat transfer to the inlet manifold. That coupled with thermal insulators could be the way forward. Also, surely the design/manufacture of a performance type modification like an exhaust manifold shouldn't suffer from failure if they are wrapped? Surely from a pure performance angle, wrapping should be encouraged?

 

I'm with you there mate, but they must have their reasons :shrug: . I was pushing to get mine ceramic coated before fitting before I even thought about wrapping it, but even that didn't happen (not happy with the longevity of the finish apparently). To me that would have been the best solution - keep the heat in, keep the gasses flowing quickly, reduce the thermal stress on the metal, and keep the engine bay temps down.

[JMC 0]

Been a while since I posted, so I thought it was time for an update. I got my Piper cam changed for a Schrick cam, had it mapped and it made 10% less power and 10% worse economy. Nice. So went back to my old chip, advanced the timing 3 degress on Darrens recomemndation and it feels more like it did before. No the chalk and cheese difference I was expecting to be honest, more a sobering realisation about claims behind what 'power adders' can actually do. Not bothered talking it for a RR assessment as to be honest I've wasted enough on trying to get this setup optimised. It seem to be running alright at the mo so am leaving it alone.

 

Enough of that annoying stuff. I've been playing around with EL sheet for the old style heater controls (as KipVR has done for the later ones) and wow am I chuffed. Below is a pic of the result - x1000 better than the original. I am offering modification of peoples control, if you fancy having them done (see my bit in the suppliers section). Also tried an LED version which is still a massive improvement over the original but cheaper. Been fun playing around with this sort of stuff again :D

[JMC 0]

Well my new parts have turned up :D 5lb Wizards of Nos bottle, bottle warmer, installation kit, Max Extreme Race edition progressive controller, fuel pressure transducer and nitrous pressure transducer. Now I just have to figure out how it all fits together :lol: Could keep me going for a bit I think.

[boost monkey 0]

That's some fine Dinitrogen Monoxide you got there, yessss indeed :norty:

[pete_griff 0]

a touch of the laughing gas - nice!

 

what power shot are you going for; are the standard rods up to it?

 

was considering doing this to mine at some point, but i'd want to upgrade the rods first as i want a 100bhp shot :norty:

 

looking good there buddy - keep us updated :)

[JMC 0]

The engine is a G-Werks 1.9l rebuild (freshly done this year), and (fingers crossed) everything should be up to the job. Initially going to be looking at a 50bhp shot, but coming in very smoothly on the progressive controller. Be quite nice to break 300bhp and 300lbft with a 1.9l 8v engine :D, but hopefully not to break the engine :lol:

[mrbeige 0]

You shouldn't break the engine, if you have the progressive controller. Are you going to run single injector, or are you doing one per port, Jonathan?

[g60karmann 0]

sweet looking kit glad to see you are keeping the all black theme going ;) have you got your 268-276 in yet?

[boost monkey 0]

As Stu said, a 50 shot on progressive shouldn't worry a G60 block at all, they're so lazy!

[JMC 0]

It's going to be a single injector. My initial thoughts were around direct injection, however after talking with Trev at the WoN his opinion was that the power increases I was after and the layout of the inlet would be fine to work with single point, which makes things much much easier (and means I don't have all the NOS and fuel lines directly above the exhaust manifold).

 

Yep, got the 268-276 in (see about 8 posts up for the saga). To be honest I wished I 'd kept my old Piper as I have not seen any large benefits (or even any benefits at all immediately after install) so would have prefered to spend my money elsewhere.

[boost monkey 0]

good stuff Jonathan, your experiences with the new cam will certainly help others make up their minds, taking one for the team so to speak! :thumb right:

 

where does the single injector go then, I'm guessing somewhere after the TB - perhaps the main plenum?

[JMC 0]

Strangely enough just before the throttle body was recommended after I spent some time at WoN. This shocked me initially given the G60 recirculation system, but the NOS will only be activated on full throttle when the recirc system is shut off. This location gives it a little more time to homogeneously mix with the air before the air/fuel/nos gets distributed between the cylinders.

 

With regards to the cam, it really comes down to the individual setup. For whatever reason with mine the Shrick was worse than my old Piper. Bear in mind though, my bad experience with the mapping this time round has tainted my view a bit. And there is no doubt that most of the high power G60 systems use Shricks. What it did show me was that you can get very respectable power from the Piper, and that any incremental improvement will be small so perhaps there are better places to spend money.

[junkie 0]

Gutted to hear the news on the cam issues Jonathan. Goes to show how people believe what they want to believe and preach till they are blue in the face that x is better than y.

 

You will break a 300bhp 8v, trust me i know lol, done it twice and once at a lower power level.

[JMC 0]

Thanks for the word of caution Simon, especially given your experience. Problem is NOS appeals to the chemist in me, and I really fancy trying it. Live and learn with regards to the cam really though, so c'est la vie. Hopefully being honest on here will make others think about equipment choices before making their minds up...

[Toad 0]

Hopefully being honest on here will make others think about equipment choices before making their minds up...

 

Yup. It's always interesting to see how people are geting on with things and how different setups react to different additions.

 

Wonder how much your 1.9 bottom end altered the effect of the cam?

 

Is the NOS just going to be activated at WOT, or progressively from almost WOT? How quickly will it cut the supply, for example when changing up a gear?

[junkie 0]

Dont get me wrong when you broke it thats when you know you had the most fun you could have from it.

 

1st time mine broke was when it was at the lower level of power, fueling ballsed up. Rebuilt.

 

2nd time was dodgy electrics, ballsed fueling up. Rebuilt.

 

£rd time was the broken manifold again, replaced, again lol.

 

Im sure it will be ok mate.

 

Read this

 

http://www.max-boost.co.uk/max-boost/

 

Especially the cam stuff.

[JMC 0]

Not sure on the difference with the 1.9l Toad - hadn't even though of that. I ran the 1.9l with the Piper cam and made 233bhp, then swapped to the Schrick (along with a new map) and it all went to pot :( By the time I checked it on the rr, I had already sold the Piper, but I swapped back to my old chip and advanced the timing, and it seems to be playing ball again. Not had it rr'd again though as to be honest at £45 a pop it was wearing a bit thin.

 

Yep NOS coms on at WOT. I'll set it up to start progessively from the lowest percentage it'll let me and have it set to build over a few seconds. Supply is cut as soon as WOT is lost. It runs off a microswitch attached to the throttle body.

[Toad 0]

Not sure on the difference with the 1.9l Toad - hadn't even though of that.

 

Be interesting to see what sort of difference it makes to airspeeds etc on cylinder filling.

[JMC 0]

That sounds like a job for Boost Monkey, Toad. Come on Jon time for some modelling....

 

Cheers for the link Simon - just had a quick look and it looks really interesting.