so with 280 are you looking for rev car out to 9000rpm. and 280 for like top speed meaning like 100mph up or what i kind of dont understand.

also why is that people set 272 at -4/-1 and seem to get best hp and tq. and then you have 280 at +2/0 humm

 

No, I'm not looking to rev the engine to 9000rpm. My HKS 280s are set to make peak power at 6400rpm, and that's exactly what they do. Peak torque is at 4400rpm. This is a result of what can be done with cam gears.

I had 272s, and I conducted A/B dyno testing with -3/-3 vs. -4/-1. The -4/-1 did give a little better peak numbers, but at the expense of spool time. I felt the tradeoff was too much, and personally speaking, neither of those two settings are optimum for that cam set.

 

very nice info have you ever dyno car at 0/0 with 280.

and how come a lot of people say 280 for stock turbo are to much. i dont see how your only gaining if anything.

and how is idle at 0/0 or you +2/0 just wondering

 

I've not dyno'd my car with the 280s at 0/0. However I theorized that the +2/0 setting would be better for my particular setup, and I've since seen two dyno tests that indicate my estimation to be correct. That setting gives better midrange torque, but requires good tuning.

IMO, the HKS 280s are best left to those who are willing to put up with some fussiness and who have the means to thoroughly tune the car. If one has cam gears and ample tuning capability, they can be made to work well with the stock turbo, although a larger turbo is a better fit.

The idle of my car at +2/0 is very choppy, but solid (no stalling).

 

well if you go with 280 and someone who only has to go to someone to tune you saying not for them. does the choppy scared people lol.

 

Actually, I am saying that a longer duration cam set functions better with a capable tuning device and competent means of tuning. Yes, the choppy idle does put some people off.

 

I torque numbers will be similiar but it is the matter of when it comes. if you have 280s you will feel bit laggy compared to 264s but you get a lot of rewards at the end of the RPM range. And dave did not test 264s.

 

Yes, but you can influence when it comes with the use of cam gears and competent tuning.

For example, here's some recorded spool characteristics with my basic setup:

HKS 272s at -3/-3 = 23psi at 3400rpm
HKS 272s at -4/-1 = 23psi at 3900rpm

HKS 280s at +2/0 = 23psi at 3500rpm

So you can see that changes in cam timing can make a significant difference in power characteristics. Also note that such changes can make for larger peak numbers, but 'peakier' power curves.

It's all a matter of what one seeks and the tools he has at hand.

 

Take his advise, the man is right... Following his advise, the HKS 280's in my car outspools my previous HKS 272 settings at -4,-1 in the midrange and makes more power at the top end... I got my turbo coming into full boost 300 rpm earlier than previous... It takes a while to fiddle the cam timing on the dyno and tuning it but the results are just satisfying... Retarding the HKS 272 inlet cams seems to hurt midrange torque thus the spool too much to be worth that extra few horsepower at the top... The best overall setting to me on the 272's seems to be very close to 0/0..

 

I know this isn't about cams so I'll make this quick. The only experience I have personally had with cam gears has been bad. End of story, do a search if want more than that. My point is I only run HKS cams as 0/0. I'd say we have had great success with our way of doing things over the years

I run the 280's in my personal RS. Other than the fact you can hear that the car is fairly aggressive the car idles, drives and performs like stock. You can visit our website and rear what the Editors of Car and Driver Magazine had to say about the car when they drove it.

Anyway, with that to answer what you should do. I LOVE the 2,000-4,500 rpm range and do feel that most drivers spent atleast 90% of their time in that range. I know I do.

Not sure what you budget is so here is what I would do that would mostly effect that area:

TME turbo. While I was doing that if it was in the budget I would port and ceramic coat the exhaust manifold and turbine housing and buy the fabricated 02 housing coated. This is the same 02 housing you can buy from Ebay if you choose. It works extremely well.

Next choice on the list is the stroker. A stroker lights up a turbo better than just about any other mod you can do. Power up top stays about the same but the low/mid range is greatly improved. Stock turbos become rediculous with a stroker spooling them. Beware though, you may end up with some compressor surge doing this route.

Many of the other mods listed will have some effect on that area but I feel the TME turbo and stroker are the two biggest. Matter of fact if you really want it to hit hard in that range use a 9.8 turbine housing with the TME turbo.

For a sales pitch to be added, I have a VERY slightly used TME turbo and a ceramic coated/ported 9.8 housing I could let go very reasonable.

Hope you get the results you are looking for.

David Buschur
www.buschurracing.com

 

Here is what my curves look like going from stock cams and gears to HKS 272/272 cams and HKS gears at +1/-1, and of course, me tuning for all of it.

 

264 and the stroker kit.

 

well if you are building a road race / auto X and just drag it to test it out. would it make sence to put in 280. i just think it does becasue your saying low end and what not is same with any diff cams, and the top end is inportent. so auto X be in like 2nd which should not be a big prooblem with spool and all. but for road racing you want top end. so i think 280 are a good all around becasue can make the most. and i mean if on street and go to hit the gas you go way over the normal driving. thats just my thought. i can be wrong if so let me know what you think. and if you put in cams and all how bad of a tune would you need. like would it run like total crap if no turn

 

And it shows that when timed accordingly, the HKS 272s will out spool the factory cams, generate more torque, and more hp. Basically, there is absolutely nothing lost and a lot gained everywhere.

The same can be had with the HKS 280s as well, again, IF they are timed accordingly.

 

Upper and Lower IC pipes will help the turbo spool faster.