cam for L28ET

[Scando]

I'm looking into upgrading the cam in my L28ET.  I want to try to get more power while keeping the good mid range torque that the car has at the moment.  The turbo provides good boost from around 3,000rpm and it seems to provide it's best power to about 5,500 rpm.  So I'm looking for a cam that works best from 3,000rpm and hopefully will still provide power up to around 6,500rpm.

 

I've been searching around the web and from the information I've found I think this is something like what I'm after:

http://www.thezstore.com/page/TZS/PROD/PEM01/10-0921

 

There's an old Zoom magazine with a feature article on Sinisha's car when it had the L28ET in it.  From how he describes it in the article this also sounds like it would give the characteristics I'm looking for.

 

These are the specs I've found:

 

MSA Stage I

Inlet Duration: 260

Exhaust Duration: 250

Inlet Lift: 0.460 inch

Exhaust Lift: 0.440 inch

 

MSA Stage 2

Inlet Duration: 270

Exhaust Duration: 260

Inlet Lift: 0.460 inch

Exhaust Lift: 0.460 inch

 

Sinisha's cam

Inlet Duration: 270

Exhaust Duration: 256

Inlet Lift: 0.470 inch

Exhaust Lift: 0.420 inch

 

I'm currently running the factory L28ET "B" grind cam which has the following specs:

Inlet Duration: 240

Exhaust Duration: 248

Inlet Lift: 0.400 inch

Exhaust Lift: 0.416 inch

 

Anyway, does anybody know any companies in Australia that do a cam for an L28ET?  I'd also be interested to know what other people think I should go for?

 

Cheers

 

Shane

[redrbzed]

Hi Shane,

The cam I had in the L28T was supplied by Datrally and was what they called their turbo grind.

I believe Wade did the grinding.

Jack, the current owner of the engine has put a bigger turbo and tube exhaust manifold

on it, he got around 240kW ATW on 98 octane unleaded.

 

cheers,

Sinisha

[Scando]

Hi Sinisha

 

So did that cam work well in the rev range I'm looking for?  (3,000-6,500rpm).  I remember reading in the article that you were always short shifting it on the track because it had heaps of mid-range torque which is what I'm after.

 

Thanks very much for the info.

[redrbzed]

 

It has been a long time since the L28T was in the car, but from what I remember with the

Gibson HR31 turbo mid range was good, power started to drop off about 5700.

As I discovered later when Jack put the bigger ball bearing turbo and good manifold on the Gibson unit and standard manifold were killing the top end.

What turbo setup are you running?

One bit of advice I can offer is get yourself a current generation Garrett ball bearing turbo as I think this will give you the biggest gains in power.

An example is my RB26, with a set of group A gibson turbos it made 150 kW @ 4000 rpm atw and 307kW @ 7100 on 100 octane fuel.

I put a set of Garrett -7 ball bearing turbos on it and made 200kW @ 4000, and 330kW @ 7100 on 98 octane fuel.

Big improvement in response and efficiency.

 

cheers,

Sinisha

 

[waxhead]

Are you referring to the stock intake or exhaust manifold when your talking about the restriction

[Scando]

There's a bit of confusion over the turbo.  The guy I bought the car off said it was a T04.  But the flange gasket is a T03 which makes me think it's a T03 exhaust housing with a T04 compressor housing.  Last weekend I was talking to the guy that actually built the turbo and he was sure it was a T04 and said it come off a Leyland bus    I think the A/R ratios on the housings are 1.00 and 0.60 but who knows if this is actually what's inside!  I've been reluctant to change it because it seems well suited to the engine but maybe we are loosing a bit there.  Maybe something I need to look into in the future.

 

The manifold is a custom made tube item.  The design isn't ideal but there's not a lot of room to work with as you would know.  The inlet manifold sitting above is a killer for any good design ideas.  We think there are some small improvements that can be made within the space we have to work with and will probably be getting a new one made up shortly because it got very hot at the first round of our series this year and has slightly warped it.

[waxhead]

Can you post a pic of your intake / exhaust side of the engine please

[redrbzed]

The turbo you describe sound similar to the Gibson HR31 unit, it had a TO4E compressor with a .6 housing and a Hiflow T3 exhaust wheel 1.0 housing.

 

Updating the turbo would give you the biggest bang for your buck.

 

Waxhead, I was referring to the standard L28T exhaust manifold.

[waxhead]

ok thanks

And you found a decent power gain by changing the manifold

Thats awesome

I was debating what to do in regard to exhaust manifolds and you just answered my question

 

Do you happen to have a pic of the one you ended up with

[Scando]

I'm not sure if I'll go for another turbo for now or not.  I've stuck with the L28 because it's been a good cheap package but if I start to spend too much on it then it's a bit of a false economy vs doing an RB25 or 25/30 conversion.  I guess if I did get a good ball bearing turbo it could be used on an RB in the future if I did decide to go that way.

 

Might have to keep an eye out for something second hand.  Thanks again for your help 

[waxhead]

Not sure how its false economy.

get on trade me buy an exhaust manifold for 200 kiwi. Intake manifolds are every where

 

if you want to go crazy then buy forged pistons but hey you will need those for the rb anyway ,

ecu well you need one for what ever engine you build

 

I actually think the l28 turbo will be cheaper than an rb,you dont have to buy the sump ethier.

 

Plus they get up to 400 at the rear wheels on the stock exhaust manifold

How much are you after

[zzzzed]

aaahh haaa you been researching on hybridz. I agree the l28et is excellent bang for buck

[Scando]

I'm after enough to mix it with a V8 supercar a carrera cup car and a 200SX with 360rwkw that's rumoured to have cost in excess of $200K to build.  Oh, I almost forgot the Falcon that broke the IP lap record for Bathurst at the easter meet..........from a standing start!  It's probably not going to happen but there's no harm in trying 

 

I could go crazy and get a set of forged pistons?..........Already got those...........

 

By false economy I mean for the power AND DRIVABILITY AND RELIABILITY I'm looking for I'll need:

serious head work = $$$$$, RB already has a twin cam cross flow head.

tuned length exhaust manifold - no room with the L series and everything has to be custom made = $$$$$ - RB has heaps of off the shelf items to choose from

inlet plenum - again custom for the L series vs off the shelf items for RB

then there's the problems with the excess intercooler piping causing extra lag because the inlet and exhaust are on the same side.

 

The L28ET is an excellent engine and I've found it to be a great reliable package for a tight budget.  I most likely will sitck with it simply because I can't afford to do an RB conversion at the moment but If I were to get serious about running at the front of my class then sticking with the L28ET vs an RB conversion would be a false economy.

[waxhead]

oh ok

i didnt realise you were trying to go that hard with it

Then your right an rb would be a better thing for you

 

[scrumpy]

Scando.  You could try getting a reground cam through WADE CAMS in Melbourne.  You could also try CROW CAMS in Campbellfield Victoria.  They may still have the last of a batch of blank billetts they got from the USA and grind to suit your specs.

 

The L series 6 cylinder blank billets are done in batches at odd intervals in the USA; so their supply is intermittent.  IMHO Crow provide excellent services; but if money is no object and you don't mind a bit of mismatching exchange rate action give MSA (California) a go or the arguabely overpriced KAMEARI stuff.

[Scando]

Thanks for the info Scrumpy.

 

Sounds like I better start ringing around some places 

[tbscobraZ]

There's also Z specialities. http://www.datsunstore.com/product_info.php/cPath/7_24/products_id/871. Price in american $.

[Aaron Neubauer]

Racer Brown on turbocharging

 

May be of some help.

[Scando]

Thanks guys.  I've kinda got sidetracked by Sinisha's comments about getting a later ball bearing turbo and haven't put much more thought into the cam.  Definatly something I'll look into shortly though.  I'm getting a bit ahead of myself, still need to get the new computer on!