Club G40 Forum

Technical => Engine and Transmission => Topic started by: Dead_dub on July 26, 2016, 12:52:07 am

Title: Rolling road 124bhp should It be more
Post by: Dead_dub on July 26, 2016, 12:52:07 am
Hi all
So I went to have my G rolling roaded on sat. Was a hot day so not the best
My car has a r1 charger 65mm pulley big vale head. Jabba chip and iduction
De wedge throttle body. Full custom ss Exhusat and manifold.
So I was told it should be around 140bhp to 160bhp.
With these sort of mods. Now I love my g and drive it every day with a big smile
But with my mate getting a breadvAn with a g40 turbo 218bhp and he keeps pulling away from me
I just wanted to see what I had.
124 Bhp. So could the hot day and it was hot in there. Make me lose some. Or is this about right for the mods.

So plans are fit the GT inlet I got. I'm getting a spare throttle body machined out to 51mm and thinking of toothed belts. Could any of these make much increase.

Any help let me know.
I'm boosting @ 0.9

Title: Re: Rolling road 124bhp should It be more
Post by: PeteG40 on July 26, 2016, 07:21:52 am
was 124bhp at the wheels or the flywheel?
Title: Re: Rolling road 124bhp should It be more
Post by: Dead_dub on July 26, 2016, 05:25:21 pm
@ the wheels bud.
I know stranded is 113bhp but I think that's @ the fly so they must be 90 something @ the wheels standed
Or can someone put this right to haha.
Title: Re: Rolling road 124bhp should It be more
Post by: GR40 on July 26, 2016, 10:27:19 pm
The heat would cause the ecu to retard timing for safety, so heat absolutely kills power. That being said, 124 seem oddly low for the specs. Start looking into it. How does your boost look like and how much are u running?
Title: Re: Rolling road 124bhp should It be more
Post by: Dead_dub on July 26, 2016, 10:59:49 pm
Yer and it was hot.
it boosts @ 0.9 think that's around 11ish psi
Max and from 0.7 before.
Anything I could be cheeking ???
Thanks.
Title: Re: Rolling road 124bhp should It be more
Post by: PeteG40 on July 26, 2016, 11:10:26 pm
Estimating drive train losses at 25% it's 165 bhp at the fly or there abouts
Title: Re: Rolling road 124bhp should It be more
Post by: Dead_dub on July 26, 2016, 11:17:10 pm
Lol I like that
The guy there said 15% and that's make 146
But I see most people with 165 at the wheels with same spec or every one adding
What they want to make it sound good haha.
Title: Re: Rolling road 124bhp should It be more
Post by: PeteG40 on July 27, 2016, 08:19:42 am
They should do a run down to see drag from the drive train to estimate losses.

It also all depends on the road, weather etc

Some rolling roads are more accurate than others!!
Title: Re: Rolling road 124bhp should It be more
Post by: Dead_dub on July 27, 2016, 12:47:47 pm
Yer I know just seem low for what done.
What anyone else with same mods getting
@the wheels.
Title: Re: Rolling road 124bhp should It be more
Post by: Jezza-7 on August 10, 2016, 10:14:20 am
mine made 171bhp, i don’t have bvh but do have 51mm tb, 1341cc bottom end and cam. My boost pressure is about 10psi and creeps up to 12psi. I’ve always used aldon for rolling road days as its very good. I’ve been twice and made 170 and 171 2 years apart.

Im was looking to put my g40 inlet back on to see if it would help with the power, a friend with a charged vr6 got a bigger inlet from another vr engine and had it dyno’d on the same day and it made a loss of power. He reckons if he was running more boost it would of made more power but the inlet is almost too big internally for the low boost he’s running.
Title: Re: Rolling road 124bhp should It be more
Post by: Jezza-7 on August 10, 2016, 10:15:29 am
a good way of telling how quick/powerful it is, is going to a rwyb at santa pod. You should be seeing low 14’s with decent road tyres.
Title: Re: Rolling road 124bhp should It be more
Post by: Dead_dub on August 11, 2016, 12:18:01 pm
Hi nice 170 bet it flys with that. As mine has Porsches of with only the 124 haha
I got hold of a GT inlet and I just had a tb machined out to 51 mm. Got a few little bit to sort then I will put them on and see how they do. I'm hoping these make the difrents as most people have the GT inlet on so we will see soon.

Yes I'm going to have to go down for a 1/4 mile if just Santa pod is 5 hour drive
Hope to get down there soon tho.

Thanks Glyn
Title: Re: Rolling road 124bhp should It be more
Post by: kwijibo_coupe on August 22, 2016, 12:11:16 am
Everyone quotes power figures from the flywheel not at the road wheels so that is one reason why yours seems a little low. So if 124bhp is with 30% off of the flywheel power then that is really 177bhp if my maths is correct. So to me that seems about right. But it also explains why your mate with 218bhp still easily pulls away from you. An extra 31bhp is a lot in these

As said a better test of power is down a drag strip. 177bhp should easily see you in the low 14s if you can get traction.
Title: Re: Rolling road 124bhp should It be more
Post by: Dead_dub on August 23, 2016, 09:26:56 am
Yer this is why I don't know we're my car is at. Some people are at the fly and some at the wheels. The rolling road I went to said 15% and at the fly is 147bhp.
But I'm liking the 177bhp sound better agin.

Any know what the moss Bhp at the wheels as my mates is 218bhp at the wheels. Or so it was sold to him. It is the breadvAn that was on eBay

Tb is in Germany getting machined GT inlet is on front mount is on if I could just get that dam 4 Allen key bolts out that crank I'd have toothed belts too. Just went to halford for a new top set of Allen keys. £20
Snapped in all of 2 mins haha.

How anyone get them out???
Title: Re: Rolling road 124bhp should It be more
Post by: kwijibo_coupe on August 31, 2016, 03:38:01 am
Did you get a printout of your RR result? The ones I have been to will always quote flywheel power as the 'top line' figure but they will usually have graphs and figures for torque and power at the crank and wheels written further down along with transmission losses, speed in whatever gear they used etc.

218bhp at the wheels would be somewhere in the region of 250bhp at the flywheel, which if true is very impressive. Is it the red mk2 that was up for £5k?

The 4 allen bolts on the bottom pulley are a pain. Instead of crawling under the car and using an allen key I go from the driver wheel arch where VW were kind enough to give you an access hole. Then you can use a ratchet and socket. Giving the socket a tap home with a hammer on each bolt might help shock it loose before you try and turn it.
If you're unlucky enough to round the inside of one of the bolt heads, I've found a 12mm 12 point socket is the perfect size to hammer on over the outside of the head and that has never failed in removing the bolt. However it makes it useless after. But your toothed belt kit should have new bolts anyway.
Title: Re: Rolling road 124bhp should It be more
Post by: Dead_dub on September 01, 2016, 09:38:58 pm
Hi yer bud got the print out. Was in 3rd gear. From 1500-6000rpm
Bout all it say. Haha.

Yer was the red one up for 5k.
I'm trying to get him to put it on the rollers.

Sorted them dam bolts out belts all on and making lots of noise still not to sure about that haha. It's fun sometimes put dose make people look.

So now have a rs trottle body(got from Germany) GT polish port matched inlet. And a front mount.

Can't say it goes any better I think it dose a bit but think it might need a new chip???
Might try ppp might need a cam first more money's and my injectiors

Might go back on the rolling road in a few weeks and see if it's better but if I can't feel a big change why waste money haha.