Valve sizes ?

Valve sizes ?

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ClassiChimi

Original Poster:

12,424 posts

148 months

Tuesday 3rd March 2015
quotequote all
Following on from the 430BV thread I'm just wondering g how much bigger the 500 valves are than the 4.6
Can anyone tell me please.
Can the 500 valves be fitted to the 4.6 heads
Would the gains be marginal?
I have steel rockers and a Kent 885 cam already fitted,,
Doms going to port and polish my heads to within a few thou of their lives so is it really worth putting the bigger valves in?
FI is where we'll all be one day so should I leave the valves alone.

SILICONEKID345HP

14,997 posts

230 months

Tuesday 3rd March 2015
quotequote all
ClassiChimi said:
Following on from the 430BV thread I'm just wondering g how much bigger the 500 valves are than the 4.6
Can anyone tell me please.
Can the 500 valves be fitted to the 4.6 heads
Would the gains be marginal?
I have steel rockers and a Kent 885 cam already fitted,,
Doms going to port and polish my heads to within a few thou of their lives so is it really worth putting the bigger valves in?
FI is where we'll all be one day so should I leave the valves alone.
Why not Turbo it ? I bet the BV heads and labour will cost close to the Turbo kit .



ClassiChimi

Original Poster:

12,424 posts

148 months

Tuesday 3rd March 2015
quotequote all
Yes Daz I'm aware the valving is expensive hense the question
It's not expensive if I'm only porting the heads and I remove engine
If I eventually go FI then surely I want the heads to be as open as possible,
So what's a good turbo install going to cost,,,
As you know I made a pigs ear of my chassis last year so engine out i can inspect chassis better,
If my riggers look like they can hang on a few more years then I can do a proper job with the right materials

Daz you have stage 4 heads, what does that include?
Do you not have a build sheet, if not why not and can your engine builder remember exactly what he did ?
I'd be wanting to rack his brains to get the exact spec.
You've got small journals have you not?
Cheers Al

SILICONEKID345HP

14,997 posts

230 months

Tuesday 3rd March 2015
quotequote all
ClassiChimi said:
Yes Daz I'm aware the valving is expensive hense the question
It's not expensive if I'm only porting the heads and I remove engine
If I eventually go FI then surely I want the heads to be as open as possible,
So what's a good turbo install going to cost,,,
As you know I made a pigs ear of my chassis last year so engine out i can inspect chassis better,
If my riggers look like they can hang on a few more years then I can do a proper job with the right materials

Daz you have stage 4 heads, what does that include?
Do you not have a build sheet, if not why not and can your engine builder remember exactly what he did ?
I'd be wanting to rack his brains to get the exact spec.
You've got small journals have you not?
Cheers Al
Long story ! I don`t know if they are stage 3 or 4 but i bet someone will know what heads they are from the power it makes .

ClassiChimi

Original Poster:

12,424 posts

148 months

Tuesday 3rd March 2015
quotequote all
So why don't you just bell the builder for a definitive answer.
You've got a ( special ) I'd want to know every detail?
You could get close to 500 ponies ( FI ) all day by the sounds of it!

SILICONEKID345HP

14,997 posts

230 months

Tuesday 3rd March 2015
quotequote all
ClassiChimi said:
So why don't you just bell the builder for a definitive answer.
You've got a ( special ) I'd want to know every detail?
You could get close to 500 ponies ( FI ) all day by the sounds of it!
Its worn me out ,the whole thing .

ClassiChimi

Original Poster:

12,424 posts

148 months

Wednesday 4th March 2015
quotequote all
Hang on, you must have one of the fastest N/A engines out there,,
So with standard Lucus AFM set up what power would you have
320 Max or more?
With porting mines close to that I reckon,,,
It has got an aggressive chip mind!
I've done some race starts and I defo can get to 60 in 4
And that's with a st clutch and hard tyres
It's got torque and screams up real quick so with better breathing and a decent ecu trumpets etc. ,,
Told you Dom built a good engine for me,,

SILICONEKID345HP

14,997 posts

230 months

Wednesday 4th March 2015
quotequote all
ClassiChimi said:
Hang on, you must have one of the fastest N/A engines out there,,
So with standard Lucus AFM set up what power would you have
320 Max or more?
With porting mines close to that I reckon,,,
It has got an aggressive chip mind!
I've done some race starts and I defo can get to 60 in 4
And that's with a st clutch and hard tyres
It's got torque and screams up real quick so with better breathing and a decent ecu trumpets etc. ,,
Told you Dom built a good engine for me,,
I would not say that ,mine is just a bit more pepped up . Not a`lot in any of them.

Tell you the truth i would not care if i had a 4l .

ClassiChimi

Original Poster:

12,424 posts

148 months

Wednesday 4th March 2015
quotequote all
Funny that,,,,
When I drive mine around the roads I use about 3mm of throttle pedal and it's still to fast,,,
There's real merit in that comment Daz,,,
How often do you open her up and feel the full power on the roads,
If you do the miles it's hardly ever unless your a dick if you ask me.
My cars now a toy so the extra engine work on the heads is more about having it than actually using it.

Fatboychims 4.0 l supercharged really impressed me,, sounded brill and ripped

I stood on the pit wall at Snett and thought what the fk, so quick up the hill.

Hey stop it's my engine were talking about,
So what's the difference in size between the 4.6 and 5 l valves.
The reason I ask is I drove Qbee's 5.0 l at Snetterton and it was a lot faster than my car and not even fuelling properly at the time.
Saying that I've got a more aggressive chip now and mines far better so ????



A900ss

3,245 posts

151 months

Wednesday 4th March 2015
quotequote all
Watching quietly...

My 450 is fairly standard, only mods are stealth cam, smooth bore, larger AFM and mapping to go with the AFM. However when I look at the shape of my power graph, it really starts to tail off above 4k and I feel it has more to give. I'm assuming it's lack of air (I know it's not lack of petrol) so better heads should release more power....


ClassiChimi

Original Poster:

12,424 posts

148 months

Wednesday 4th March 2015
quotequote all
I'm thinking I'll need bigger fuel injectors etc
Let's hope someone with more tuning knowledge will be along to explain your graph, def looks like it's peak performance and torque drops off a bit early but the bhp looks to be about right for your set up!
A900ss, was your car re mapped and or chipped after the new cam etc,,

A900ss

3,245 posts

151 months

Wednesday 4th March 2015
quotequote all
ClassiChimi said:
A900ss, was your car re mapped and or chipped after the new cam etc,,
Cam fitted in 2013 but the car was fitted with a larger AFM and remapped last autumn.

QBee

20,903 posts

143 months

Wednesday 4th March 2015
quotequote all
You've got a lot of lovely mid-range torque there Karl.
BHP is for willy wavers, torque is what makes the car drive well and fast.
Your car will be quick, both on road and on track.

phazed

21,844 posts

203 months

Wednesday 4th March 2015
quotequote all
Alun. Here's my old 5.0 which was a flyer.

Robs stage 4 heads, ported inlet, 72mm plenum, trumpets, etc, etc.
Still running 14 CUX but with a tweaked chip, standard injectors.



Graphs are cats in then out!

ClassiChimi

Original Poster:

12,424 posts

148 months

Wednesday 4th March 2015
quotequote all
Thanks Peter, that's rather impressive,,
Who ported the inlet manifold for you ( Rob )
Standard injectors,, even more impressive

If I can get 320/330 bhp from the 4.6 I'll be happy,
It's got loads of torque already so it's just about freeing up the top rev range a bit.

I don't want to bore you but your 4.6, what spec did you go to and what did that produce.
I really want to leave the valves alone but if it's vital to get the last bit out of it I'll consider it carefully.

I'd go FI but I like N/A !!!
As usual until some business is conducted I'm not sure what my budget will be,
It's gonna happen though.
Thanks for your input Alun

phazed

21,844 posts

203 months

Wednesday 4th March 2015
quotequote all
I forgot yours was a 4.6 Alun.

Heres my 4.6 with a solid Tornado looky likey cam by kent, solid lifters and all the other bits and pieces from the 5.0.


Chuffmeister

3,597 posts

136 months

Wednesday 4th March 2015
quotequote all
Both impressive dyno charts Peter. I'm surprised that the cats made such a massive difference!

phazed

21,844 posts

203 months

Wednesday 4th March 2015
quotequote all
Chuffmeister said:
Both impressive dyno charts Peter. I'm surprised that the cats made such a massive difference!
At their age they well have been partially blocked.

QBee

20,903 posts

143 months

Wednesday 4th March 2015
quotequote all
phazed said:
Chuffmeister said:
Both impressive dyno charts Peter. I'm surprised that the cats made such a massive difference!
At their age they well have been partially blocked.
Fur balls or cat litter? Peter is well acquainted with my elderly cats..... laugh

ClassiChimi

Original Poster:

12,424 posts

148 months

Wednesday 4th March 2015
quotequote all
I've removed precats, that's obviously helping already.I'll have to put Alex old de cat Y back on!
That's really good figures for the 4.6,,
I'll make a shopping list that includes ear muffs, ?
So the head work in conjunction with all the other bits is important to get near that figure, you were running coil packs when on the rollers with the 4.6 Peter ?