Balance shaft question

identiti66

Sorry if this has been done to death, I did a search and couldn't find exactly what I wanted so here goes.

In the event that the trip to Carls is not possible when the time comes (i am trying to make it do-able though), I've been searching for a more local option.

I've also asked, at the same time, about balance shaft removal and one response I got back was:

some people who go racing remove the balance shafts as their not interested in a silky smooth engine & don't mind the harshness & vibrations that come from removing the shafts in exchange for a little more power.

This is not the impression (of the end result) from reading threads on here. My car (Vec B) is our only source of transport, and I'm old-ish, is there a likelihood of it being a bit harsh and rough for daily driving?

evocarlos

removing the balancer shafts does nothing in terms of idle and if you're not reving past 7000rpm there's not much point removing them

things to consider each shaft is 2.2kg that spin at 2 x the engine speed (eg engine speed 6000rpm the shafts are doing 12000rpm)
so that 4kg the engine is having to spin at any given rpm (parasitic loss) removing them removes that power the engine needs to use to spin them

personally i dont consider removing them as gaining BHP the effects of removing the weight from the rotating mass makes the engine rev more freely the same as fitting a lighted flywheel

also its not something that can really done with the engine in the car the subframe has to be unbolted the get enuff room to slide the front shaft out

here you can see that anyone that tells you removing the shafts make the engine shake all over the place and is undrivable is full of shit 🙂

https://www.youtube.com/watch?v=vSGQuOpT6ok

identiti66

Thanks man... I very much doubt this car will get revved past 7k. Ever. It'd be a bit of a shock if it got to 6k to be perfectly honest.

Which is a bit of a relief since I'm not planning to have the engine out any time soon.

I'm really just looking for ways to squeeze a little performance out for not much effort (or cash). Not into big bhp any more but a little pick-me-up in the 0-100 would be cool.

evocarlos

it is one of the mods that's £0.00 🙂

i should've said its a must for over 7000rpm the 4kg spinning at 14000+ rpm try to escape the block lol
but even on a standard engine you can tell the difference pickup is better and the engine is faster accelerate

identiti66

Gotcha

But now I want them removed again!!.. D'Oh!!..

Think I'll just have to settle for them being there unless something hideous happens and the engine has to come out - and there happens to be a competent person nearby..

Dave_Gilbert

I wasnt bothered about removing them. But i need a new clutch sooooo im going with a lightend flywheel to help pickup speed

n having turbo issues aswell so a new turbo is in order so im thinking pull the engine ro do the turbo, clutch/flywheel so while im there i should pull the balance shafts( makes sence while its out).

But if u do start modding you cant stop lol.

identiti66

Lordy no .. this is not going to turn into a slippery slope to modding hell.. started meddling in the 80's and stopped around 15 years ago.. way too old for all that stress now.

Just a little extra poke, coupled with reliability, would be perfectly fine for me now.

Maybe a nice burbling song (none of that nasty raspy crud) and a little induction roar. The rest is cosmetics, I'm happier doing that these days.

But those superchargers do look seksy eh?

Dave_Gilbert

The whine a charger makes aswell.

onve u have a go in 1 you will want 1.

I have had to go with a turbo on mine but would love a charged astra

milo

Dave Gilbert said:
The whine a charger makes aswell.

onve u have a go in 1 you will want 1.

I have had to go with a turbo on mine but would love a charged astra

https://www.youtube.com/watch?v=Ej-RzrkdiHg

Made me fall in love with coupe again best sound that can ever come from an astra imo🙂

positive

evocarlos said:

each shaft is 2.2kg

Hi evocarlos,

Are you sure about its weight?
I've recently found this one:

http://www.speedsterclub.nl/forum/viewtopic.php?f=8&t=5173&start=75

evocarlos

cant say ive ever bothered to weigh them 🙂

vocky

I believe the weight was Internet inspired, people always say 2kg each on the net.

patricks

identiti66 said:
Sorry if this has been done to death, I did a search and couldn't find exactly what I wanted so here goes.

In the event that the trip to Carls is not possible when the time comes (i am trying to make it do-able though), I've been searching for a more local option.

I've also asked, at the same time, about balance shaft removal and one response I got back was:

some people who go racing remove the balance shafts as their not interested in a silky smooth engine & don't mind the harshness & vibrations that come from removing the shafts in exchange for a little more power.

This is not the impression (of the end result) from reading threads on here. My car (Vec B) is our only source of transport, and I'm old-ish, is there a likelihood of it being a bit harsh and rough for daily driving?

Yes good post! I have also toyed with the idea of balance shaft delete too but there are wildly different reports out there on the benefits. Further, the descriptions of the benefits and disadvantages are qualitative rather than quantitative. So a question for those that have done it. If an air box mods and panel filter is a 3 out of ten and say a ported throttle body a 4 out of ten and a cam swap is a 6 out of ten and a supercharger is a ten out of ten what would you rate the performance increase out of ten for a balance shaft delete???

For those that have done it how does

vocky

the engine revs better, like a lightened flywheel, so not really power but better revving. GM did state they require 5bhp to turn each, however they never said at what rpm that was recorded at.

There are approx 100 cars running the delete in the UK, zero mechanical issues reported so far.

dewismotorsport

After removing mine it certainly felt more responsive much like a lightened flywheel as vocky says.

So on your scale I'd probably say a 5/10

I've seen no side effects from removing mine

patricks

dewismotorsport said:
After removing mine it certainly felt more responsive much like a lightened flywheel as vocky says.

So on your scale I'd probably say a 5/10

I've seen no side effects from removing mine

Well that's certainly worthwhile doing then. Never actually experienced a lightened flywheel but 5/10 sounds good to me. Took me about 3 hours to clean and port my throttle body (only a moderate porting cause i didnt want to risk dash lights) and that to me gave a noticeable if modest improvement in engine responsiveness and acceleration so it was time and effort well spent.

identiti66

patricks said:
Well that's certainly worthwhile doing then. Never actually experienced a lightened flywheel but 5/10 sounds good to me. Took me about 3 hours to clean and port my throttle body (only a moderate porting cause i didnt want to risk dash lights) and that to me gave a noticeable if modest improvement in engine responsiveness and acceleration so it was time and effort well spent.

I have a throttle body sitting in the shed waiting to be ported/polished. I'm putting it off because I'm not sure what I'm doing but it is another job on this years list (oh so many things to get done, we'll never get round to them all)

patricks

identiti66 said:
I have a throttle body sitting in the shed waiting to be ported/polished. I'm putting it off because I'm not sure what I'm doing but it is another job on this years list (oh so many things to get done, we'll never get round to them all)

If your interested i have one thats ported and ready to go in that's tested and defo wont cause issues

corsaZ22se

balancer delete is more noticeable gains when driving than a ported throttle body. about the same as a lightend flywheel or pre cat delete.
so removing balancers, removing pre cat, fitting a 200cpi sport cat and larger downpipe, exhaust system, lightend flywheel, panel filter all done at the same time you would feel a noticeable difference throughout the rev range and how it picks up.

identiti66

corsaZ22se said:
so removing balancers, removing pre cat, fitting a 200cpi sport cat and larger downpipe, exhaust system, lightend flywheel, panel filter all done at the same time.

Dunno about at the same time, or the lightened flywheel, but this is where I'd like ours to be by the end of the year.