stifler1603
New Member
what is the difference in using a neo vvl head verses a stock gtir head on the gtir engine? alot of the guys in the caribbean are doing it.
neo vvl head
- Thread starter stifler1603
- Start date
warpspeed
Well-Known Member
doesn't just flow better.....eliminates the problem off rockers jumping and allows a much high rev limit.
Its a similar idea to the vtec heads giving you 2 cam profiles so you have much better airflow at lower revs giving better spool for the turbo and then better airflow at high revs too....
Get better valve springs to reduce the risk of valve float, Honda H22a valve springs will fit but may need a slightly thicker shim to give a fraction more preload, using these springs has allowed others to rev to 9.6k revs, some will say 9.8k but thats pushing it a bit....
Supertech do bigger valves too if you really want to go for it...
The squish pads can be machined out also.
As for cams, sr16ve cams are better but a fair bit of overlap, sr16ve n1 cams are better still but extremely hard to find (I was very lucky that I ended up with a pair by accident)
Kelford do aftermarket cams for these, I think Cat cams do to but don't hold me to that
To fit the head isn't just a simple bolt on but it's not that difficult, holes in head need opened out slighty for the gtir's slightly larger head bolts or you could just fit a 1/2" head stud kit, the dowel holes in the head need opened out a fraction too.A hole needs drilled and tapped in the back of the head and an oil pipe run to suppy the extra oil the head needs for the vvl, a kit is available from G-spec.
You'll need a switch to work the vvl also, Granatelli switches seem to be a common aftermarket solution..
When you buy a head you'll need to make sure you get the inlet side to as gtir throttle bodies are too small to work and fitting the vvl head would just be a waste of time then.
vvl heads have side feed injectors so that will need changed also unless you plan to keep the fuel rail etc
Its a similar idea to the vtec heads giving you 2 cam profiles so you have much better airflow at lower revs giving better spool for the turbo and then better airflow at high revs too....
Get better valve springs to reduce the risk of valve float, Honda H22a valve springs will fit but may need a slightly thicker shim to give a fraction more preload, using these springs has allowed others to rev to 9.6k revs, some will say 9.8k but thats pushing it a bit....
Supertech do bigger valves too if you really want to go for it...
The squish pads can be machined out also.
As for cams, sr16ve cams are better but a fair bit of overlap, sr16ve n1 cams are better still but extremely hard to find (I was very lucky that I ended up with a pair by accident)
Kelford do aftermarket cams for these, I think Cat cams do to but don't hold me to that
To fit the head isn't just a simple bolt on but it's not that difficult, holes in head need opened out slighty for the gtir's slightly larger head bolts or you could just fit a 1/2" head stud kit, the dowel holes in the head need opened out a fraction too.A hole needs drilled and tapped in the back of the head and an oil pipe run to suppy the extra oil the head needs for the vvl, a kit is available from G-spec.
You'll need a switch to work the vvl also, Granatelli switches seem to be a common aftermarket solution..
When you buy a head you'll need to make sure you get the inlet side to as gtir throttle bodies are too small to work and fitting the vvl head would just be a waste of time then.
vvl heads have side feed injectors so that will need changed also unless you plan to keep the fuel rail etc
nismo gti-r
Member
VE head flows better,especially the exhaust side.
Valvetrain is also more stable for crazy rpm.
please note you cannot use larger valves and uprated cams with stock sr20 pistons.
You will need deep valve pockets for higher lift cams and bigger valves...
Valvetrain is also more stable for crazy rpm.
please note you cannot use larger valves and uprated cams with stock sr20 pistons.
You will need deep valve pockets for higher lift cams and bigger valves...
Agreed.
vpulsar
Well-Known Member
Apart from being able to rev to stupid levels what else does it do, There are plenty of 500 + bhp Pulsars going about these days and my new one will be around 400 and spool stupidly quick so I don't see benefit per cost pound wise ?
Rob
Empty Pockets
New Member
It obviously gives you a broader powerband, what's better, power from 3k-7k, or 3k-9k ? Think of the benefit when you're choosing a turbo that kicks off at 4.5k+, although the benefits are no less on a small turbo, i.e that awkward corner where you have to change up/down mid-corner that you can now hold gear through.
vpulsar
Well-Known Member
You'll also be needing new rods then because though the standard pulsar ones are pretty tough I don't think I'd want to trust them doing 9000 rpm for long so as I said it's going to be very expensive to do it's not just fitting the head, Plus I don't like engines that rev that high I like my grunt low down personally.
Rob
Empty Pockets
New Member
You wanted to know advantages ? Rods would be fine, they're tougher than the VE one's, no ? The whole point is you can have the low down grunt that you like, with extra up top, i.e a broader powerband ?? The only downside is you'll have to pay for it (just like any other mod you've bought), so it's not really a point if you modify your car, unless you get everything free.... plus it's not expensive if you're in the market for having head work done anyway ? Wether you like it or not, isn't reallly relevant dude 
vpulsar
Well-Known Member
Whether you like it or not, isn't really relevant dude
I suppose not lol.
Not for me but I can understand the appeal for those that want to scream the nuts off there engines.
I'm just having my engine built at the moment but I think I'll stay on plan.
Rob
Empty Pockets
New Member
That's it mate, disregarding rev limit, at 400-450bhp the only thing you need to do is cams, so if you're not intending on headwork already, port, polish, springs, valves etc then it may seem expensive, it's more than peak figures though, it's that usable powerband, i've seen some truly nasty graphs on here of GTiR's, stock turbo cars of 350bhp coming on power at 3.5k plus and dropping at 6.5-7k, 500bhp plus one's with 2-2.5k powerbands, nothing untill 5k then dead at 7-7.5k. If anyone says they wouldn't want to be able to safely increase their powerband by 25-50% they're lying, for sub 2k i think it's the best value mod going, especially if you were looking to mod the 54c head anyway, if built for application the revs aren't an issue, honda's will rev at 9k all day, even rb26's are ok at 9-10k with minor mods, super upgrade if your engines capable of making power above the stock rev limit.
I have mine for the flat torque curve they give.
As for price if your going to upgrade the gtir motor the intake is the only extra cost plus the initial price of the head. Complete motors in Australia are hard and expensive to get no idea on prices for you guys. Imo spend the extra and buy the X-trail VET, I'm a little bias tho.
I'm surprised more people haven't done this swap.
As for price if your going to upgrade the gtir motor the intake is the only extra cost plus the initial price of the head. Complete motors in Australia are hard and expensive to get no idea on prices for you guys. Imo spend the extra and buy the X-trail VET, I'm a little bias tho.
I'm surprised more people haven't done this swap.
interesting to read about the issues in fitting a VE head. No doubt that that having a broader powerband makes sense under all circumstances.
VVL kicked in YO!