Engine Machining... What works? (G60)

[Cheapmods 0]

So if any of you have checked out my build thread you know my project keeps getting bigger and bigger. Well now I've ordered up some +2mm valves and I'm getting the machine work done for that, and getting the block hot tanked. I was wondering what other machine work you all would suggest doing while she's under the knife. :scratch:

 

BTW I don't plan on making it 1.9l just yet, so don't even suggest it :lol:

 

Just a note, i have the charger ported stage 4 rebuild from BBM with RSR outlet, FMIC, larger injectors, BBM asymmetric cam, and BBM stage 4 chip. (just in case that would influence your responses)

 

Blueprinting, balanced or knife edged crank, ported throttle body or intake mani... anythings welcome. Please just speak from experience. I'm just wondering what stuff made a tangible difference and what just looks good on a spec sheet.

 

Thanks :salute:

[Yandards 0]

Ported/knife edged throttle body is always a good investment on a G60, most people report a noticeable difference in throttle response after doing it.

 

As for the rest, well, blueprinting the inlet manifold to head and throttle body is always a good idea along with the exhaust manifold to head and downpipe.

 

Any chance you could get some close-up pictures of the BBM stage IV up?

 

Knife edged crank, titanium valve spring retainers, uprated springs are only any real use if you plan to rev the engine higher, which if you have a smaller pulley on the charger you wont want to do anyway. The knife edged crank, lightweight flywheel and alloy cambelt wheels (autotech items) will only make the engine rev up faster due to the loss in energy required to overcome the weight of those components. Balancing is always a good bet along with weight matching of the pistons and rods - it all helps to stop wasted energy through vibration, worth doing on the older 4 cylinder blocks (16v/G60) as the build tolerances were not as exact as the VR6.

[Cheapmods 0]

here's your close ups

 

 

[Cheapmods 0]

in my instance i think i'll wait on the exhaust portion, as i plan on getting a full exhaust system...just not right now.

 

As far as the intake side, i'll more than likely do the throttle body porting and smoothing the intake mani. As stated she's already going in for oversized valves so it only makes sense. I have a 68mm pulley on the charger and have a lightweight (8lbs) flywheel, so that's why i was considering the knife edged crank. In this case i have a windage tray, so it's purely a weight reduction vs an oil splashing matter, but i'm not sure if the mod is cost effective...any comments?

 

I'm getting the block and pistons, etc hot tanked to remove all the crud. what's involved in the weight matching?

[Toad 0]

The porting looks rather nice on that charger. :)

[Sonicriot13 0]

Yeah, that charger looks the t*ts. :D

[Yandards 0]

in my instance i think i'll wait on the exhaust portion, as i plan on getting a full exhaust system...just not right now.

 

As far as the intake side, i'll more than likely do the throttle body porting and smoothing the intake mani. As stated she's already going in for oversized valves so it only makes sense. I have a 68mm pulley on the charger and have a lightweight (8lbs) flywheel, so that's why i was considering the knife edged crank. In this case i have a windage tray, so it's purely a weight reduction vs an oil splashing matter, but i'm not sure if the mod is cost effective...any comments?

 

I'm getting the block and pistons, etc hot tanked to remove all the crud. what's involved in the weight matching?

 

Basically its ensuring that all your pistons/conrods are the same weight within a certain tolerance, if think about the velocities involved in a spinning engine at 1000rpm then even a few grams difference across the bottom end means losses in engine efficiency. Most people tend to get the pistons weight matched to around 5 grams of each other (about 0.15 of an ounce) and get the conrods within the same limits - you can then mix and match the rods and pistons to try to get the best average across the 4 cylinders. Then get the whole let dynamically balanced, its not going to give you massive gains but after the chip and pulley and headwork then its all gets a lot more expensive for not a lot of bhp.

 

As for the crank, it depends what kind of driving style you are after really, I don't think it makes a massive difference in terms of power output but it will make the engine accelerate faster, any reduction in oil mist drag is a good thing and given that the G60 produces more oil mist than your average car it will help but dont expect more than 5hp at the very most.

 

Thanks for the outlet view of BBM's stage 4 process, I have been looking at it for a while and that shot proves it's a very fine piece of work indeed.

[Cheapmods 0]

nothing but praise for BBM :notworthy: very helpful folks too. When i started my project i gave 'em a run down of my plans & they affirmed that i was on the right track.

 

I agree with the cost per hp increase you hit at a certain point, yan. Although i haven't even put this thing together, i pretty much got all the applicable parts for my stage of build. I tore it down bare & i'm rebuilding it like new & i'd hate to realize that there was something simple i could have done after the fact, ya know.

 

i'll check into the weight matching price, but i'm thinking the crank will be too expensive at this point.

 

Thanks for the help.

 

Oh & :salute: on the kind words about the charger, she's a true beauty!!

[Henny 0]

Lighten and balance the crank - makes a HUGE difference to the smoothness of both the engine and the power delivery....

 

knife edging the crank I feel is overkill on a G60 engine... you're restricted to how high you can rev the engine by the charger, so why do a modification that's all about getting higher revs out of the engine? Fit a baffled sump and windage tray instead and you'll have gained more useful advantage in a G60 engine than with a knife edged crank... ;)

 

Lighten and balance the flywheel - makes the engine rev up/down much faster and I think a little more smoothly

 

Match the weight of the pistons/rods - helps with the engine balance - rev up/down faster, less wasted energy in an unbalanced engine - basically, the parts are put onto a very accurate set of scales, and then material is removed to make all 4 rods weigh exactly the same, and the same with the pistons... mine have less than a gram TOTAL difference across all 4 pistons and rods!

 

blueprint the blocks oil and waterways build up layers of crud over the years, and weren't particularly well cleaned out from the factory casting process anyway, so opening/cleaning these up a little helps the oil flow around the engine and helps to keep the engine running cooler and more efficiently... 8)

 

Blueprint the head (or even better, gasket match!) and inlet/exhaust manifolds... the more restrictions to the flow of gasses through the engine you can remove, the more power you stop throwing away! ;)

[Cheapmods 0]

awesome post, henNy! :salute:

 

...now how much did those things run you? :scratch:

 

 

Yan- You mentioned that it's about what driving style i prefer. I'd have to say that i'm looking to make my car mimic my motorcycle as much as possible in all areas. I know she won't be there just yet, but that's the goal. Torquey engine feel, free fast revving, tight chassis, great brakes. The kind of car that's point-and-shoot on the highway.

 

I remember the 1st time i drove a 997 turbo fitted with PCCBs. I thought "WOW! this is just like my bike! you see a gap, stab the pedal and BAM! you're there! And the brake..... incredible!" :notworthy: :notworthy:

 

Now i know the G60 is no Porsche, but it doesn't mean i can't aspire to make my car the best it can be in its current form.

[Henny 0]

cost wise?

 

Ummm... :scratch: from memory (it was a while ago now...) I think it breaks down as...

 

Balancing the pistons and rods to that level was £250 this included machining the pistons to make 'em miss the oil squirters in my G60 block as they're 83mm Mahle pistons not originally intended for a G60 engine, so the actual balancing part was probably only £50 or so...

 

Lightening and then dynamically balancing the crank - £150

 

dynamically balanced and lightened flywheel - £100

 

block blue-printing/oil and waterway clearing/gasket matching cost me another £30 on top of the overboring cost...

 

Head, well, I bought one of G-Werks/CNC heads Big valve, CNC machined, polished heads and had the inlet and exhaust manifolds matched and flowed at the same time, and got a good price as mine was one of the prototype heads...

 

All the rest of the porting (throttle body, intercooler inlet/outlet, etc etc etc...) I did myself for almost no cost other than time...

 

P.s. it's HenNy, not Henry... ;)

 

Now i know the G60 is no Porsche, but it doesn't mean i can't aspire to make my car the best it can be in its current form.

speak for your own G60... mine used to scare the pants of most Porsche drivers I came across, and it'd out brake most of 'em except for the real animal ones... :D :lol:

 

If that's what you're after out of your engine, then that sounds very much like a description of the engine I've got in mine...

[Cheapmods 0]

Henny - please note post edit above :lol:

[Yandards 0]

If you want your G60 to rev like a bike then the more weight you can shave off components the better, as Henny already mentioned getting all the relevant parts weight matched helps with an engines balance.

 

It is worth getting the cam lobe removed and shaft shaved down on the oil pump/dizzy drive shaft as it is designed for a mechanical fuel pump and it useless on a G60. Get some of the lightweight alloy cam wheels from autotech, basically anything that removes weight from the rotating parts of the engine will get you closer to your goal of a motorbike style power delivery.

 

I can vouch for Henny's car too, it pulls like a train and the torque delivery is just awesome across most of the rev range, as close to an ideal torque curve profile as you can get.

[junkie 0]

From experience i was just going to write what Henny did but he did it all.