Ready To Put In 272 Cams. What Supporting Mods?

[335]

Hello

I am putting HKS 272 cams into my '91 R32 GTS-T with 116000 Km on it. The car will be tuned and will have a bigger fuel pump and possibly a R33 turbo on it as well as a front mount. Should I replace the valve springs and lifters? Or should the stock ones be fine? Also what other mods should I do to support this? I want my engine to last at least 5 more years. I don't race but use my car as a daily driver. I will be going fast on the highway sometimes. Maybe Maybe I will take it to the track twice a year just to go faster.

Help

[NYTSKY]

You might have wanted to do a bit of research before you bought those size cams because not only will you need some heavy duty valve springs,you whole head will need a good going over.

Valve springs,solid lifters and maybe abit of machining for that size cam to fit.

Good luck.

[r3240sx]

What is the lift on the cams? That is what will determine whether or not you need to do machine work, and maybe solid lifters/new valve springs.

I bought tomei 256's w/8.5mm lift and they dropped right in.

[Adriano]

Pretty sure hks 272's have 10.2mm lift which will require head machining to clear the lobes, and hks step 2 valve springs. These cams are way overkill for the turbo you are running and are really 300rwkw + territory, my guess id you will lose power everywhere except at 6-8000rpm where you may gain 10-15rwkw, but the turbo will definately be the limiting factor.

[PM-R33]

272 degree cams for a RB20 running a RB25 turbo is overkill and a waste of money. You will need solid lifters, springs and might as well do valves and guides to do it properly, the amount of money that is going to cost is a complete waste for such a small turbo. Should have gone 256's which are a direct bolt in and don't need anything replaced and would work a lot better with such a small turbo.

Edited March 10, 2008 by PM-R33

[335]

Hello

These cams were given to me, so I took them. They are HKS 272 degrees N2 with 8.53 lift. My mechanic said they should drop in. They are made for the RB 20. Came out of another 32.

So since they have 8.53 lift instead of the 10mm mentioned earlier, is this better? So can I use these without all the stuff having to be done as mentioned earlier? If I do keep these which turbo would be a appropriate turbo to use for these? If I get Tomeis should I get the pon cams or the pros?

Help please

[Cjmartz2k]

where are you located?

[R31Nismoid]

Hello

These cams were given to me,

Well sell them.

They are too big for a tiny turbo upgrade that wont even really outflow the stock setup

[335]

I am in Japan If I keep them which turbo should I get? Which Tomei cams should I get?

[Cjmartz2k]

Okinawa? Poncams for that or 256 HKS cams.

[Gav]

I think RB26 with HKS or Tomei stroker kits match well with 272 cams

[r3240sx]

I think RB26 with HKS or Tomei stroker kits match well with 272 cams

I think You'll loose some low end using 272's over 256's, but with the same lift as the pon cams, these cams could be made to work. 8.5mm lift will not require any upgraded valve springs, lifters, or machine work. They will drop right in. However. You're idle might suck, and street performance will probably suffer. If I were you, I'd definately take the downsides to those cams for free, instead of spending $700 USD on a set of pon cams. I think if you had a set of adjustable cam gears, you could tune those cams well enough to work.

I put my pon cams in, and was suprised to find there's not much difference between these and stock. I think I got more midrange, more noise everywhere, and it pulls pretty well to redline. I didnt notice any change in idle or street driveablility. If the 256's are this mild, I dont think you'll have a problem with 16 degrees more duration, seems like a waste to toss those in favor of 16 less degrees. Just my 2 cents..

Good luck

[335]

So if I put these in I will have bad street performance but good powder for mid to upper power range? But with adjustable cam gears I could probably get good street performance?Is this with tune or without?

[R31Nismoid]

Mate with 272's on a p|ss tiny turbo, your going to have all round sh|t performance if you install these.

I highly doubt you'll see any top end increase as the RB25 turbo simply is NOT going to outflow the factory setup.

Cam gears, no cam gears... 272's are a pointless upgrade regardless of them being free or not.

RB20's are not big on low/mid range as it is, and all your going to do by installing silly cams is hurt whats already a sore point.

Sell them and buy something appropriate, or better yet, stick with factory and get a tune.

[335]

I understand about the RB25 turbo but what if I use HKS 2510 or 2530?

[R31Nismoid]

I think RB26 with HKS or Tomei stroker kits match well with 272 cams

[limpus]

I understand about the RB25 turbo but what if I use HKS 2510 or 2530?

Still too small if you ask me...those cams are really suited to a slightly more extreme setup...

[r3240sx]

Mate with 272's on a p|ss tiny turbo, your going to have all round sh|t performance if you install these.

I highly doubt you'll see any top end increase as the RB25 turbo simply is NOT going to outflow the factory setup.

Cam gears, no cam gears... 272's are a pointless upgrade regardless of them being free or not.

RB20's are not big on low/mid range as it is, and all your going to do by installing silly cams is hurt whats already a sore point.

Sell them and buy something appropriate, or better yet, stick with factory and get a tune.

Okay, I guess I just dont know what I'm talking about...

All I was trying to say is, judging by how mild my 256's are, it seems like you could make the 272's with 8.5mm lift work well. Adjustable cam gears could help if you need to get rid of some overlap.

In order to make any setup work properly, yes you do need a tune.

I've never used 272's though, so I cant tell you from personal experience. For what its worth, if I could do it again I'd look for some 264's with an 8.8-9mm lift. It just doesnt seem like these 256's did much, we'll let the dyno tell though.

He's right though, in order to notice a difference you're going to need a turbo thats capable of flowing more than a tiny 260-280 hp.

GT2510's and gt2530's are so damn small, I really dont even know why people bother with those turbo's, when an rb25 turbo is what $2000 less? Lots of boost with a 2835 or a 3037 may make those cams usefull, other than that Nismoid is right, stock cams would be best.

However, if you do upgrade turbos, the cams were free.. I'd do some experimenting before I decided to sell them.

[335]

Okay, I guess I just dont know what I'm talking about...

All I was trying to say is, judging by how mild my 256's are, it seems like you could make the 272's with 8.5mm lift work well. Adjustable cam gears could help if you need to get rid of some overlap.

In order to make any setup work properly, yes you do need a tune.

I've never used 272's though, so I cant tell you from personal experience. For what its worth, if I could do it again I'd look for some 264's with an 8.8-9mm lift. It just doesnt seem like these 256's did much, we'll let the dyno tell though.

He's right though, in order to notice a difference you're going to need a turbo thats capable of flowing more than a tiny 260-280 hp.

GT2510's and gt2530's are so damn small, I really dont even know why people bother with those turbo's, when an rb25 turbo is what $2000 less? Lots of boost with a 2835 or a 3037 may make those cams usefull, other than that Nismoid is right, stock cams would be best.

However, if you do upgrade turbos, the cams were free.. I'd do some experimenting before I decided to sell them.

Ok I understand. So what you are saying is that in your opinion, the 2510 and 2530 turbos are a waste of money when a RB25 turbo can get the same results?

If I went with a 2835 or 3037, how much lag would I get in my car compared to the 2510, 2530, RB25 turbos?

So I am assuming that even with a tune, you don't have any good figures with using the 256 cams you have?

[R31Nismoid]

GT2510's and gt2530's are so damn small, I really dont even know why people bother with those turbo's, when an rb25 turbo is what $2000 less? Lots of boost with a 2835 or a 3037 may make those cams usefull, other than that Nismoid is right, stock cams would be best.

However, if you do upgrade turbos, the cams were free.. I'd do some experimenting before I decided to sell them.

$2000 ?

HKS 2530's are cheap as chips. $1500 second hand, and a darn sight better than the RB25 turbo.

Its just that the RB25 one is cheap, the 2530 is the BEST (and makes more outright power with resonable midrage)