G35 Camshaft Install
Excellent info Dave.. Unless it is free i don't think it is worth it. I do agree though if u do cams then might as well do everything and have reliable high reving De engine. If i was checking out a G35 at a meet i would love to ride in one of those that u described than be in a twin turbo 700whp G.
Originally Posted by DaveB
I agree that cams really aren't worth it, but I don't know if I'd say they're better for boost unless you buy cams specifically designed for boost. NA cams on the boosted motor often results in worse power numbers than the OEM cams.
Cam install is not for the faint of heart and they must be done the right way or you're going to potentially have a slower car (keep reading). The job can be done while the motor is still in the car, but it's quite a easier to do it when it's out. Guys that have done cams on VQ30s and VQ35s tend to spend around $1200-1500 for install. The cams themselves are $1,100-1,400 plus you'll need valvesprings ($300+), assorted shims ($50), and tuning ($400+). The tune is needed to adjust A/F ratios in the high rpms and to also increase idle rpm and the rev limiter. Install isn't hard, it's just labor intensive. When it's all said and done, you're probably looking at $3000-3,200 and that's just the tip of iceberg (continue reading).
You need to understand the implications of cams though. Cams will trade low and mid rpm power for higher rpm power. Around town, the motor will feel far more docile and weaker. The cams will trade anywhere from 15 to 20whp from idle to 4500rpms for some serious power gains from 5500rpms to 7500rpms+. You're completely changing the powerband of the motor therefore two other things really need to happen to make use of this new power.
1) Change to deeper gears
2) Improve high rpm reliability of the motor
The additional torque multiplication of the deeper gears is needed because you're low rpm power is weaker and you need to get the motor into the higher rpm powerband quicker. Without the gears and an extended rev limiter, the car will be slower in the 1/4 mile. With a 6MT, you'd need at least 4.08 gears and with that comes a reduction in mpgs. The VQ35DE is not designed for high rpm (7000rpm+) operation therefore you're going to need to at least add the VQ35DE RevUp rod bolts and oil pump. Ideally, you should add stronger rods too because the stockers are pretty weak. With the gears, rods and oil pump, the VQ35 should be happy living in the 7500rpm range, but now you're talking about another $3K. While you're at it, you might as well install the Cosworth intake plenum ($1,000) because now you have a motor that can breath hard enough to make use of the killer plenum. And if you've gone that far and the motor is out, why not clean the heads up a little for $1000 and gain a few more HP? Taking the motor out could save little in overall labor and it's my understanding that removing the motor isn't super labor intensive.
So, in the end you'd have a pretty dang reliable 7500-7800rpm revving VQ35 making probably close to 300-310whp and probably have put the NA G into the 12.7 range on DRs. Now the question is, for $8K is it worth it to you?
Cam install is not for the faint of heart and they must be done the right way or you're going to potentially have a slower car (keep reading). The job can be done while the motor is still in the car, but it's quite a easier to do it when it's out. Guys that have done cams on VQ30s and VQ35s tend to spend around $1200-1500 for install. The cams themselves are $1,100-1,400 plus you'll need valvesprings ($300+), assorted shims ($50), and tuning ($400+). The tune is needed to adjust A/F ratios in the high rpms and to also increase idle rpm and the rev limiter. Install isn't hard, it's just labor intensive. When it's all said and done, you're probably looking at $3000-3,200 and that's just the tip of iceberg (continue reading).
You need to understand the implications of cams though. Cams will trade low and mid rpm power for higher rpm power. Around town, the motor will feel far more docile and weaker. The cams will trade anywhere from 15 to 20whp from idle to 4500rpms for some serious power gains from 5500rpms to 7500rpms+. You're completely changing the powerband of the motor therefore two other things really need to happen to make use of this new power.
1) Change to deeper gears
2) Improve high rpm reliability of the motor
The additional torque multiplication of the deeper gears is needed because you're low rpm power is weaker and you need to get the motor into the higher rpm powerband quicker. Without the gears and an extended rev limiter, the car will be slower in the 1/4 mile. With a 6MT, you'd need at least 4.08 gears and with that comes a reduction in mpgs. The VQ35DE is not designed for high rpm (7000rpm+) operation therefore you're going to need to at least add the VQ35DE RevUp rod bolts and oil pump. Ideally, you should add stronger rods too because the stockers are pretty weak. With the gears, rods and oil pump, the VQ35 should be happy living in the 7500rpm range, but now you're talking about another $3K. While you're at it, you might as well install the Cosworth intake plenum ($1,000) because now you have a motor that can breath hard enough to make use of the killer plenum. And if you've gone that far and the motor is out, why not clean the heads up a little for $1000 and gain a few more HP? Taking the motor out could save little in overall labor and it's my understanding that removing the motor isn't super labor intensive.
So, in the end you'd have a pretty dang reliable 7500-7800rpm revving VQ35 making probably close to 300-310whp and probably have put the NA G into the 12.7 range on DRs. Now the question is, for $8K is it worth it to you?
I love this forum!!
If it were me and I had $8K to blow, I'd add a lower boost single turbo setup and make sure every piece of it was quality with no "bandaids" or short cuts. I'd also invest in the best ECU management system available and also add the stronger tranny internals from the Titan 5AT tranny. I would probably add the Cosworth plenum too. My goal would be 350whp/350wtq with a super fat powerband from 3000 to 6000rpms and little, if any, lag. That setup should be good for mid 12s@107ish on DRs. I'd think you could get away with this for around $6K.
I used to think the way many posts are here… however, I have spoken with a couple of people (one previous Nissan engineer) and a renowned tuner…. It seems there is possibly potential that isn’t exactly what has been construed here.
Once my current projects are complete (which are taking way longer than expected), I might be getting back to performance orientated tasks – and this is one that is on a relatively long list.
It very well may be all for not – but I’m not aware of enough real world installs (in line with some of the things I’m considering) to deter me from going forward.
Granted – it’s much easy to go FI – but that’s the case across the board as compared to NA… call me a sadist, but I’ve taken the challenge of NA performance (without doing full build – yet).
When the project commences I’ll be sure to post progress… but it will be a while (too many aesthetic projects with major delays are in process)…
Once my current projects are complete (which are taking way longer than expected), I might be getting back to performance orientated tasks – and this is one that is on a relatively long list.
It very well may be all for not – but I’m not aware of enough real world installs (in line with some of the things I’m considering) to deter me from going forward.
Granted – it’s much easy to go FI – but that’s the case across the board as compared to NA… call me a sadist, but I’ve taken the challenge of NA performance (without doing full build – yet).
When the project commences I’ll be sure to post progress… but it will be a while (too many aesthetic projects with major delays are in process)…
Registered User
Joined: Dec 2003
Posts: 2,514
Likes: 5
From: Marietta, Georgia
Mathematically you can accurately estimate [within 2-3%] what any cam will do assumming you can graph the profiles.............whether the valve geometry can follow the cam is another matter.
http://www.performancetrends.com/ca20.htm
http://www.profblairandassociates.co...HEAD_Main.html
http://www.ricardo.com/engineeringse...px?page=valdyn
http://www.performancetrends.com/ca20.htm
http://www.profblairandassociates.co...HEAD_Main.html
http://www.ricardo.com/engineeringse...px?page=valdyn
Great job Dave, thank you.
I should have clarified that IMO cams are not worth it unless you are boosted and building the motor anyway (and getting the right cams). You could also be building the motor for an N/A beast but one way or another I would do more than the cams when spending that kind of time on the motor.
I should have clarified that IMO cams are not worth it unless you are boosted and building the motor anyway (and getting the right cams). You could also be building the motor for an N/A beast but one way or another I would do more than the cams when spending that kind of time on the motor.
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Joined: Apr 2008
Posts: 1
Likes: 0
From: California
Well, if you're happy at only 7100rpm or so rather than 7500rpm... you can save quite a bit of cost there.
But for a long lasting motor once you're in all that trouble........ think about it. Since I already had the engine out, cams and valvesprings were a no-brainer.
But for a long lasting motor once you're in all that trouble........ think about it. Since I already had the engine out, cams and valvesprings were a no-brainer.
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Joined: Jan 2012
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kinetix intake manifold
Did you feel a big difference when you installed kinetix intake manifold? are you boosted?
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