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Discussion Starter #61 (Edited)
I needed to gauge how fast the car actually was as the feel of it had changed. So I thought I would try and get some timings done as the stop watch doesn't lie. I consider the Veyron a fast car and had an ambition to match that at normal'ish speeds. I also had a little look at what other GT-Rs had recorded and decided the 100 - 200 kph was a good gauge of where the car was at.

I used the ecutek performance logger as figured it was hands free and would be good enough for what I needed. I found an opportunity fairly early on and recorded a 5.3 sec run. The Veyron does it in 4.8. So I was happy enough considering I knew I wasn't driving the car properly and there were still set up and map tweaks taking place.

A few days later I managed a 5.1. So I thought great, maybe I can match the 4.8 second target.

Another few changes later and starting to get to grips with the car an opportunity arose and the thing knocked out a 4.6 second run! Which I was delighted with. I also think there is more to come too.

So I'm happy the car is suitably fast but also refined and smooth and not excessively terrifying.
 

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Discussion Starter #62 (Edited)
I spent some time detailing my build choices. I'll reflect on those now.

Fuelling. Initially a concern. Has proven to be 100% ok. The pumps work great and aren't very noisy at all. On occasion the car takes longer to crank than is ideal but I think this is down to many aftermarket pumps check valves that stop the fuel clearing out the lines are not as good as OEM. I can live with this as it's only on occasion and if I turn the ignition on and let the pumps prime I think it would eradicate the issue entirely. The injectors have done everything asked of them. I wouldn't want to run much more power through them though.

Intercooling. This is an interesting one. On the road it's absolutely ok. On the dyno running a street cooler seemed to present a few complications from heat soak which required the dyno to be run a little faster at low rpm to ensure the higher rpm inlet temps were still sensible.

As I say on the road it's been fine however I went to Santa pod on Saturday and logged the one run I got and the inlet temps got close to the point where I might want to do something about it. I will continue to monitor this and will update accordingly. I'm still confident the ETS street is the best street available and that under most circumstances it is indeed good to support 1000bhp. Given my time again, I would seriously consider just going for a decent race cooler. Either the ETS or Litchfield dominator would probably be my first choices.


The turbos. I really like! I still need more time to get used to them and how to get the best out of them but I'm enjoying driving the car. I also have headroom for another 200+lbs torque and 200/300bhp if desired with a few additional supporting mods (intercooler, injectors and probably fuel lines and rails plus further gearbox upgrades - not the end of the world, as the major expense has been incurred).


The engine. I love it. The LM sport engine is brilliant. I am happy to have opted to spend a little more over a regular rods and piston build. The block cracking was unfortunate before but that was just bad luck more than anything else. Although I'm happy it happened when it did. The way the car revs is fantastic. Feels really good and sounds just like a normal engine when ticking over. Perhaps a little more mechanical noise when the bonnet is up nothing anyone would necessarily pick up on.


I also went for a number of other non-power mods. Quaife front diff and billet case. LM Handling kit and also had one of the suspension arms replaced due to the original having worn out. I am blown away by how the car feels now. So much more stable and planted than before. Plus the steering feel is so much more improved with a more decisive return to centre. I did have an issue with the handling kit where it squeaked when going over bumps. Litchfield have looked at it and replaced a couple of the bushes and it is back to being silent again. The diff seems to have made a difference too. No more hopping and bouncing during low speed manoeuvres and when driving the car seems to put the power down nicely and remains stable even if the there is a lot of power being directed to the front wheels. I highly recommend these things. I have found myself sideways on one or two occasions now and both times I felt like I was in control and it was sorted without issue. previously it could be an unnerving experience.



That's all for now. I'm really happy with the car and think it will get even better as I get more used to it.

There was a thread on here a while back that asked 'who needs 1000bhp'. The answer is everyone. Everyone needs it!
 

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A great write up l, thanks!

What***8217;s the lag like in comparison to standard now that you***8217;ve had plenty of map revisions?
 

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Discussion Starter #64 (Edited)
Definatly different from OEM. These are the EFR 7663 which are somewhat bigger than stock though.

It requires a different driving style and I would say without the additional rev capability then I would think twice about fitting these. I'm sure if I was running ALL of the torque and boost then the turbos would probably be spooling even earlier.


I need to get the hang of rolling boost, that's for sure!


The car starts making boost as low as 3k rpm, but it takes a few more revs to start building solid boost.

I'll try and get a video clip of it from lower RPM so you can see how the car revs and boost builds.
 

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Discussion Starter #65
Managed to get my stock rods and pistons back. Thought I would share.

These had covered 78k in total. 40k miles / 6 years at Stage 4.25. 650bhp but I always ran with restricted mid range torque (580lbsft). Don't go thinking it was a soft tune though - the car dished out several beatings to others with higher mid range torque numbers and was good enough in this form to finish top 10 in the handling part of TOTB 2017 and do 196mph at VMAX

I thought they looked alright actually. Would be fascinating to see an XRAY of them. But interested in anyone else's views from what can be seen here.









 

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they look good. No sign of bending?? I have been doing loads of reading and it seems like rolling on throttle in high gears nails most rods. If the tuner has not limited boost from 4th onwards this seems to be an issue. I know boost is limited to say 19psi overall (tune dependent) but in-gear boost can also be limited to save the rods.

Seems like you had a very good tune:thumbsup:
 

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Discussion Starter #67
they look good. No sign of bending?? I have been doing loads of reading and it seems like rolling on throttle in high gears nails most rods. If the tuner has not limited boost from 4th onwards this seems to be an issue. I know boost is limited to say 19psi overall (tune dependent) but in-gear boost can also be limited to save the rods.

Seems like you had a very good tune:thumbsup:

I tended to drive in a way that I thought would be sympathetic to the rods. So would never let it slam down gears in Auto (never drove in auto really), I wouldn't open the throttle a great deal from low revs and would also let it rev.

My boost wasn't limited in 4th onwards though. I asked for everything the car and turbos would make in the high rev range.

I also had the car running at less than 600lbs which I think makes a difference.
 

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I tended to drive in a way that I thought would be sympathetic to the rods. So would never let it slam down gears in Auto (never drove in auto really), I wouldn't open the throttle a great deal from low revs and would also let it rev.

My boost wasn't limited in 4th onwards though. I asked for everything the car and turbos would make in the high rev range.

I also had the car running at less than 600lbs which I think makes a difference.
I did not explain myself very well.

Boost limited in higher gears in low revs only. So, say in 2nd gear you could make 15psi at 3k, maybe in 5th you could only make 10psi at the same revs.

I agree i think most of it is down to how its driven.
 

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The car starts making boost as low as 3k rpm, but it takes a few more revs to start building solid boost.
gtr mart,

Not sure if this helps you with your analysis since boost is a measure of engine restriction as well as an indicator of potential performance.

With the standard EFR 7163, I have the following boost.

0.5 bar boost @ 2700 RPM
1.0 bar boost @ 3270 RPM
1.5 bar boost @ 3600 RPM

Syvecs chart below shows where the numbers come from.

 

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Discussion Starter #72 (Edited)
I am interested to see a picture of the upper rod bearing.

thanks
I'll see what I can do, but will take a few days. I assume you mean the bearing joining the rod and the piston?

can you explain what you mean by that?

ps: congrats on your new beast!
Thanks. I have been doing a number of map tweaks after logging data on the road. The Ecutek (V7) software has boost by gear so in my main map the general boost level is set just under 2 bar. I can then run lower boost in the first three gears, which had been set lower.

The boost by gear was then amended by the tuner to enable upto 1.8bar in 1st and 2nd and then 1.9 bar in 3rd.

I have set this (for now) to run 1.5 bar in first, 1.8bar in 2nd and then 1.9 bar in 3rd onwards. I intend to keep making adjustments to this as I dial in the car.


We also raised the rev limit in all gears to 8500 as the first 2 gears were at stock 7200 which came round too quickly.
 

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Thanks. I have been doing a number of map tweaks after logging data on the road. The Ecutek (V7) software has boost by gear so in my main map the general boost level is set just under 2 bar. I can then run lower boost in the first three gears, which had been set lower.
ahh yes, that's what I was hoping you've meant :) I heard that Ecutek 7 would maybe support boost by gear. Is it adjustable on the fly by the enduser (through cable and laptop/phone bluetooth) or only by the tuner?

The boost by gear was then amended by the tuner to enable upto 1.8bar in 1st and 2nd and then 1.9 bar in 3rd.

I have set this (for now) to run 1.5 bar in first, 1.8bar in 2nd and then 1.9 bar in 3rd onwards. I intend to keep making adjustments to this as I dial in the car.
that's fantastic! that way you can dial everything in perfectly regarding traction and gearbox protection :thumbsup:
 

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Discussion Starter #74 (Edited)
Hugh Keir ***8211; PTSYS;5751201 said:
gtr mart,

Not sure if this helps you with your analysis since boost is a measure of engine restriction as well as an indicator of potential performance.

With the standard EFR 7163, I have the following boost.

0.5 bar boost @ 2700 RPM
1.0 bar boost @ 3270 RPM
1.5 bar boost @ 3600 RPM

Syvecs chart below shows where the numbers come from.







Thanks Hugh, that is useful and I spent some time looking at my data as a result. I don't have a clean log to help make it clear what boost is made when so will pull a log for this and have a look. Probably 3rd gear pull, WOT from low revs and just a 10 second log so I get decent scale and granularity.

From what I could see it does look like you're making the boost 200 / 300 rpm sooner, but I guess as you are running ALL the torque and have a built box, and my compressor wheel is a little larger I suppose this isn't a surprise.


You mention about boost being a measure of engine restriction. I understand the bit about engine restriction, in that the better flowing the engine the less boost that is needed - or the harder it is for the turbos to make it.

The comment about boost being an indicator of potential performance however, I hadn't heard or read about before. Could you explain this a little more please.

What indicates more or less potential?
 

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You mention about boost being a measure of engine restriction. I understand the bit about engine restriction, in that the better flowing the engine the less boost that is needed - or the harder it is for the turbos to make it.

The comment about boost being an indicator of potential performance however, I hadn't heard or read about before. Could you explain this a little more please.

What indicates more or less potential?
gtr mart,

As you correctly point out, a better flowing engine requires less boost to make the same power.

Since we need boost to make power, boost shows there is the potential to make power with the above caveat on flow.

My engine has fully gas flowed heads, inlet and exhaust manifolds and has bigger valves, so should flow well, making it hard to compare against other engines.

The only way I know of to confirm the potential is a dyno or in-gear acceleration.

The above Syvecs log is from the dyno run referred to earlier where I made 840 wheel horse power at 1.8 bar and 6700 RPM.

I believe the engine delivers more than the dyno shows, since I used 2 bar boost at TOTB and rev a good 1000RPM more.

The engine will also take more ignition in the mid range as can be seen from the knock trace, have still to sort this.

All of the above shows potential, the only verification I really have is the in-gear times.

Still fancy your turbos though!
 

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Discussion Starter #76
Hugh

Thanks for the data. I pulled a log in 3rd gear to see how the car was boosting.

I knew mine wouldn't be as sharp as yours due to: My larger compressor wheel, my limted torque level. I also did this pull in 3rd gear where I imagine yours, if on the dyno was in 5th and with more resistance holding the car back which aids boost build.

With the standard EFR 7163, I have the following boost.

0.5 bar boost @ 2700 RPM - Mart = 3025
1.0 bar boost @ 3270 RPM - Mart = 3800
1.5 bar boost @ 3600 RPM - Mart = 4400*

*The 1.5 figure is actually the boost that's maintained for a few thousand revs then rising to 1.9/2 bar at 8000+ rpm (remember I wanted 700lbs flat for the entire rev range to aid drivability).

Therefore I would argue that the 1.5 bar figure would be better if the boost target was 2 bar at that point.

Boost readings are from the boost gauge figure on the Ecutek log
 

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Discussion Starter #77
Just looked at a 5th and 6th gear log. I don't need 1.5 bar to make the power it seems. I can see from the boost chart there are adjustments going on with the WG to hold the boost down. Only as the revs get higher does the boost build further.

I'm running a 2018 spec Litchfield Sport engine which includes gas flowed and polished heads (as well as being reinforced) and also some nice valves and seats. On the basis that the car seems to make reasonable numbers I think I'm pretty happy with that and it shows that there is more potential in both the engine and turbos should I decide I need more.
 

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Hugh

I imagine yours, if on the dyno was in 5th and with more resistance holding the car back which aids boost build.

With the standard EFR 7163, I have the following boost.

0.5 bar boost @ 2700 RPM - Mart = 3025
1.0 bar boost @ 3270 RPM - Mart = 3800
1.5 bar boost @ 3600 RPM - Mart = 4400*
Mart,

My Dyno run was made in 4th gear, so if you have a 4th gear pull, you should be able to compare boost figures.

Will have a look through some other logs I have to see if I have a 3rd gear pull to see what my boost is in 3rd.

Not really considered what the difference in boost would be in gears, but agree that higher gears will show more boost.
 

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Discussion Starter #79
Just noticed the website I was using the host pics (photoio.com) seems have been down for a few days so all the pics have disappeared. if it doesn't come back soon I'll find another site and re-post them. Maybe try and get the sizing right this time around!
 

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Discussion Starter #80 (Edited)
Been a while since I updated this thread. Car has been running nicely and getting better and better with each map revision and set up tweaks.


Car running well and I'm getting the hang of driving it progressively. There is certainly a health warning with bigger power. Roads I was previously very familiar with, now seem different and naturally you are limited on where you want to go full throttle. On the flip side, I feel far less compelled to do so meaning it hasn't been an issue so far, I don't feel like I'm missing out. I would say though that if you want to smash your car in everywhere then 600 - 750 is probably the sweet spot.

I have spent far to much on petrol these last 4 - 6 weeks. Must be nearly £1000! And covered less than 2000 miles. I tend to just run in the max power setting and regulate what the cars doing with the throttle (piece of cake on Ecutek V7 - throttle and boost is very linear).

Looking at the Litchfield Ecutek instructions it did say that Map 1 (95ron) is actually a fuel save map too and I noticed when running that setting the MFD fuel consumption gauge is back to where it was before (30mpg when cruising). On the main map I'm lucky to see 20mpg and the reality is when moving along I'm probably closer to 10 - 15mpg
 
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