New Owner Engine Mod advice

[CV8revver]

Hi guys. I purchased a cv8 big boot model end if last year. It's currently got 41k on it and the following mods:
K&n, modified mAf pipe
Remote bleed
Ls7 clutch, mishimoto alloy rad
Wortec cat back

I'm going to get a rip shifter and upgrade the brakes soon and get some suspension bits from pedders.

What do you guys think would be a good MOT friendly engine build for around 400whp that wouldn't break the bank?

[mfp4073]

CV8revver said:

Hi guys. I purchased a cv8 big boot model end if last year. It's currently got 41k on it and the following mods:
K&n, modified mAf pipe
Remote bleed
Ls7 clutch, mishimoto alloy rad
Wortec cat back

I'm going to get a rip shifter and upgrade the brakes soon and get some suspension bits from pedders.

What do you guys think would be a good MOT friendly engine build for around 400whp that wouldn't break the bank?

Welcome to the fold, that's a very clean looking super low mileage car you have there. It looks like it had some great mods already. The rip shifter is a good mod and takes the slop out the standard shifter.
To get 400 flywheel HP, is easy, but to get 400 rear wheel HP, is something else.
You will need headers, sports cats and a remap to get 400 at the flywheel, but you will have to add a cam, intake and throttle body to get near 400 horses to the rear wheels.
If you search through this forum you will find out what other owners have done in the past. If you click onto my user name, you will see all the mods I've carried out on my car and that's pretty much what you need doing before going into the engine mods ( in my opinion)
You can end up spending an absolute fortune on these cars so it's best to plan out what you want from the car before you spend any cash.
I hope that helps a bit......John

[Phillphill]

Supercharger

[CV8revver]

mfp4073 said:

Welcome to the fold, that's a very clean looking super low mileage car you have there. It looks like it had some great mods already. The rip shifter is a good mod and takes the slop out the standard shifter.
To get 400 flywheel HP, is easy, but to get 400 rear wheel HP, is something else.
You will need headers, sports cats and a remap to get 400 at the flywheel, but you will have to add a cam, intake and throttle body to get near 400 horses to the rear wheels.
If you search through this forum you will find out what other owners have done in the past. If you click onto my user name, you will see all the mods I've carried out on my car and that's pretty much what you need doing before going into the engine mods ( in my opinion)
You can end up spending an absolute fortune on these cars so it's best to plan out what you want from the car before you spend any cash.
I hope that helps a bit......John

Thanks John. Seems like headers are the next stop for me then, wortec recommended AAS. Bit of a trek from Cardiff but I bet they're worth it.
Trev

[mfp4073]

Contact Stuart at AAS and he will book you in, be aware they are very busy so it might be a month or so for a slot.
I had my headers ( mid length ) and sports cats fitted by them a few years ago, and they have been faultless. No knocking on the chassis or split welds, there quality in all reality is the best.
The car might be a few days in the workshop as they make headers to order ( I think? )
On the other hand I'm sure someone on here got AAS to send out a set for them to fit themselves.
If you do actually go up there it might be worth getting a few other jobs done at the same time if required.......cost permitting of course.
Rest assured they know their stuff, and just as importantly they are an honest bunch.

John

[Lincsls1]

Plenty of history on here to search through.
This is one example of an interesting old thread...

https://www.pistonheads.com/gassing/topic.asp?h=0&...

I can also vouch for AAS, done a bit of work on my Monaro last year and happy with their workmanship and knowledge.

[CV8revver]

Thanks both, I'll plan a trip with the girlfriend later in the year :L
After that I'll get a remap and see where I'm at horsepower wise.
Fun times ahead!

[vxr2010]

I have the same car , it has what used to be called the focus pack , it was around 4000£ upgrade , it was headers k n panel filter , bigger intake pipe plus larger maf , headers sports cats plus a cat back and remap , it adds around 100 bhp , it is about 325 or so at the wheels , the problem i get is mot time can be an issue , if you add other mods like a cam and bits i think a legal mot maybe getting out of reach , you have supercharging but it’s not cheap , one thing i found was modding is a slippery slope lol

[fred bloggs]

vxr2010 said:

I have the same car , it has what used to be called the focus pack , it was around 4000£ upgrade , it was headers k n panel filter , bigger intake pipe plus larger maf , headers sports cats plus a cat back and remap , it adds around 100 bhp , it is about 325 or so at the wheels , the problem i get is mot time can be an issue , if you add other mods like a cam and bits i think a legal mot maybe getting out of reach , you have supercharging but it’s not cheap , one thing i found was modding is a slippery slope lol

If that lot adds 100 bhp and shows 325bhp at the wheels, a stock one should show 225 at the wheels ? not sure about that. A remap+exhaust maybe 40.


Bone stock my vt2 made 265 at the wheels on surrey RR. Makes more now but on different dyno.

Only way to get(realistic) over 400 at the wheels and an MOT is boost.

[CV8revver]

fred bloggs said:

If that lot adds 100 bhp and shows 325bhp at the wheels, a stock one should show 225 at the wheels ? not sure about that. A remap+exhaust maybe 40.


Bone stock my vt2 made 265 at the wheels on surrey RR. Makes more now but on different dyno.

Only way to get(realistic) over 400 at the wheels and an MOT is boost.

Is there a way to get close to 400 at the wheels whilst staying NA and being MOT friendly?

[Chilli Sauce Pete]

Hi,I had a cv8 with LS1,Harrop 112 supercharger,wortec exhaust but no cam,540 fwhp ,400 rwhp,mot ok,hope this help's

[fred bloggs]

CV8revver said:

fred bloggs said:

If that lot adds 100 bhp and shows 325bhp at the wheels, a stock one should show 225 at the wheels ? not sure about that. A remap+exhaust maybe 40.


Bone stock my vt2 made 265 at the wheels on surrey RR. Makes more now but on different dyno.

Only way to get(realistic) over 400 at the wheels and an MOT is boost.

Is there a way to get close to 400 at the wheels whilst staying NA and being MOT friendly?

I doubt you can with n/a.

[mfp4073]

Reading this thread, we have entered the " how much power does the car really make"
You have to take things with a pinch of salt....there are so many variables that can effect HP readings on the day.
With that in mind my car put out about 325 HP at the rear wheels that was on a decent rolling road. My car has got an equivalent Focus pack fitted. This equates to approximately 425HP at the flywheel or there abouts.
So ...headers ( mid length on my car ) sports cats, X pipe, then a cat back. I also replaced the entire air box and filter with a VCM cold air kit. The engine ( a VZ 5.7 ) was then given a Wortec remap.
The standard HP rating was 349HP at the flywheel on this model.
Monkfish used to offer a couple of cam packages in the past, they were said to make near enough 500HP or 530HP if you had the rocker arms replaced as well. Each pack was mot friendly but that 530 HP was a bit too close regarding emissions.
The more power you make N/A, the greater the chances of having low speed drive issues, especially driving in traffic. You also increas fuel consumption and as mentioned you might have some mot problems.
If you aim for say 450-480HP that is a pretty realistic power level without any major issues.
I forgot to mention my car has a 390. diff which makes a big difference to how the car drives, some have said it feels like an extra 50HP kick up the backside!
Please be aware that I'm no expert, these are just my opinions. There used to be some really knowledgable people on this forum a few years ago, but they have sadly moved on.
Anyway hopefully it's given you something to ponder!!!!!

John

[selym]

mfp4073 said:

Reading this thread, we have entered the " how much power does the car really make"
You have to take things with a pinch of salt....there are so many variables that can effect HP readings on the day.
With that in mind my car put out about 325 HP at the rear wheels that was on a decent rolling road. My car has got an equivalent Focus pack fitted. This equates to approximately 425HP at the flywheel or there abouts.
So ...headers ( mid length on my car ) sports cats, X pipe, then a cat back. I also replaced the entire air box and filter with a VCM cold air kit. The engine ( a VZ 5.7 ) was then given a Wortec remap.
The standard HP rating was 349HP at the flywheel on this model.
Monkfish used to offer a couple of cam packages in the past, they were said to make near enough 500HP or 530HP if you had the rocker arms replaced as well. Each pack was mot friendly but that 530 HP was a bit too close regarding emissions.
The more power you make N/A, the greater the chances of having low speed drive issues, especially driving in traffic. You also increas fuel consumption and as mentioned you might have some mot problems.
If you aim for say 450-480HP that is a pretty realistic power level without any major issues.
I forgot to mention my car has a 390. diff which makes a big difference to how the car drives, some have said it feels like an extra 50HP kick up the backside!
Please be aware that I'm no expert, these are just my opinions. There used to be some really knowledgable people on this forum a few years ago, but they have sadly moved on.
Anyway hopefully it's given you something to ponder!!!!!

John

Good post again John.

[CV8revver]

Chilli Sauce Pete said:

Hi,I had a cv8 with LS1,Harrop 112 supercharger,wortec exhaust but no cam,540 fwhp ,400 rwhp,mot ok,hope this help's

That does indeed! Do they still make them anymore? Or is it just try looking for a used one?

[stu vxr]

I am supercharged, saved for years to get this and read a lot of threads on here, I have to admit I always liked the idea of staying NA, but you have to spend big money to get good power plus town driving and economy would not be good.

If I was building a track car then definitely I would go NA, but if you want real power for the road which is head and shoulders above stock then it has to be Forced induction.

I don't have a cam but full wortec and sport cats headers etc, think you need this to get the best from the charger.

It may be best to wait for a car to come up with the mods you want before you spend, think man maths may come into play.

[mfp4073]

selym said:

Good post again John.

Thank you, I do try my best....then again Mrs mfp4073 does say I'm quite trying!!!!!! she goes on bit about other things as well.......but that's for my therapist to sort out!!!!!!!

[Lincsls1]

Whilst its true it would be a lot cheaper to just buy a car with the mods already done, I think part of the fun is to have a project and upgrade it knowing the step by step process taken and exactly who's done what etc..
I think if I was to look at a significant power hike for my Ro I'd look at an engine swap. Would the 6.2 LS3 drop in a Ro from a knackered VXR8? If not I think there are other crate engines that might.

Edited by Lincsls1 on Tuesday 15th January 19:45

[mfp4073]

Lincsls1 said:

Whilst its true it would be a lot cheaper to just buy a car with the mods already done, I think part of the fun is to have a project and upgrade it knowing the step by step process taken and exactly who's done what etc..
I think if I was to look at a significant power hike for my Ro I'd look at an engine swap. Would the 6.2 LS3 drop in a Ro from a knackered VXR8? If not I know there are other crate engines that would.

I totally agree, it's far better to buy a car with most if not all the mods already done, assuming you can find a car in good condition these days.
However as Lincisls1 says, it's great to have a project car and modify it yourself to what you want.
Mind you It's hellishly more expensive that way, but my man maths say it's OK, especially when the cost is spread over the best part of 12 years in my case.
Any of the LS series of engines will fit a Monaro even a 7 litre, but you need to sort out the reluctor wheel on the crank if your original engine was a 5.7.....(something like that anyway.) I remember Roger Keys of Monkfish saying that the best bang for buck on a Monaro road car is fitting a Supercharger. If only.......

[selym]

Lincsls1 said:

Whilst its true it would be a lot cheaper to just buy a car with the mods already done, I think part of the fun is to have a project and upgrade it knowing the step by step process taken and exactly who's done what etc..
I think if I was to look at a significant power hike for my Ro I'd look at an engine swap. Would the 6.2 LS3 drop in a Ro from a knackered VXR8? If not I think there are other crate engines that might.

Edited by Lincsls1 on Tuesday 15th January 19:45

Phillphill has an LS3 engine in his Ro, I'm almost definite.

I'm enjoying grabbing bargain bits at glacial place, with the ultimate aim of handling better, stopping better, sounding better and going better.