Cams

djdrastic · Post by **djdrastic** » Sun Dec 03, 2006 4:12 pm

Hi . have any of you guys upgraded your cams ? I've been looking around for some cams for the CA18DET motor but I haven't seen anything yet . The only sort of info I can get about CA18DET cams seems to be the CA18DE inlet cam trick.

Thanks
Any Help Greatly Appreciated

Desertrat · Post by **Desertrat** » Sun Dec 03, 2006 9:32 pm

From what I have read on the det the cams don’t help that much, rather spend your money on something else. Well that is what I have read haven’t tried it my self.

The Calibrator · Post by **The Calibrator** » Mon Dec 04, 2006 6:44 am

Cams and headwork make a HUGE difference on a turbo engine. A friend of mine has a 1400 bakkie with a CA18det he made around 50whp more going to 264 deg cams.

Ran a 10.73@209km/h at North vs South with 8" slicks, turbo only@2bar

Check below for what cams did to a SR20

http://www.sr20forum.com/showthread.php?t=179358
[/img]

johansx · Post by **johansx** » Mon Dec 04, 2006 10:11 am

NA cams don't work too well in boosted motor because of the overlap. You need cams cut for the turbo motor. My only worry is drivability in traffic, because my car is a daily driver

The Calibrator · Post by **The Calibrator** » Mon Dec 04, 2006 2:08 pm

NA cams don't work too well in boosted motor because of the overlap

Err that statemant is based on old information. The new way is to run N/A type overlap on mild installations.
The amount of exhaust manifold pressure will play a huge role in determining how much overlap to run. The closer exh manifold pressure is to boost pressure the more overlap you can run.
The other interesting piece of equipment are called vernier pulleys by this I mean proper vernier gears not stock gears with the slot widened.

You can pretty much make the overlap what you want it to be on a dohc motor.

johansx · Post by **johansx** » Mon Dec 04, 2006 3:01 pm

After my SR20 head was gas flowed, the performance went down, noticebly... Added X-force stainless branches since, no improvement. Guess it is time to add cams to optimise the breathing. Intake and turbo is still standard.

ps. do you volunteer to sort it out for me early in the new year?

The Calibrator · Post by **The Calibrator** » Mon Dec 04, 2006 6:44 pm

After my SR20 head was gas flowed, the performance went down, noticebly

Then something was done wrong possibly cam timing? Or a bad valve seat job.

If you are willing to pay my price and do the job my way I am willing to sort it out.

johansx · Post by **johansx** » Mon Dec 04, 2006 8:49 pm

I agree, something is wrong, but it is a long story I will not bore everybody with right now

Engineering was done by Alan Y Brink in Pretoria and assembled by Mause (who also did the porting) at the time. My initial reaction was wrong cam timing as well, but somebody else who had a workshop at the time confirmed the cam timing was right, not that I trust his opinion at all!

Originally fitted a 3" e xhaust and Unichip, went from about 100rwkw to 119rwkw. 0-100 about 6 to 6.1 seconds, top speed well over 260km/h on the clock, easy. Since the gas flow and X-force the time is now 7 secs 0-100 and top speed on clock 245 max! No get going and no top end. Runs hot as well.

Before I hand over my car, I would like to have a development plan, things I want to add while it is sorted. Please add your comments on my plan.

1. 3" down pipe between turbo and top of exhaust. Should complete the picture as far as the exhaust requirements.

2. FMIC, 600x400x70 or whatever. (obviously lag is a concern)

3. With the small IC removed from the fender well, I want to use that space to scoop up fresh air direct to the inbox.

4. Bigger MAF, that standard thing looks way to small, maybe Z30 or whatever is the best/easiest/available. Maybe mod the housing on the origanal sensor?

The unknown factors are the still standard jets, FPR and fuel pump. The FPR gauge stays at the same spot at full tilt.

Maybe upgrade the T28 to a GTRS, bigger fuel system, a nice loud vent to atmosphere BOF

I don't want to run all the standard parts at 100% utilization, a little paranoid that way

Lots of meters to monitor everything : Fuel presure, boost, EGT etc.

Whenever I look at some of the overseas forums you see a lot of money spend on brand names cosmetic parts... not my intention to have a show car, just a reliable car with exceptable fuel consumption if I by chance want to cruise at legal speed... and a 200+ rwkw monster when I am in a hurry... (as usual

)

The Calibrator · Post by **The Calibrator** » Mon Dec 04, 2006 9:30 pm

1. 3" down pipe between turbo and top of exhaust. Should complete the picture as far as the exhaust requirements.

2. FMIC, 600x400x70 or whatever. (obviously lag is a concern)

3. With the small IC removed from the fender well, I want to use that space to scoop up fresh air direct to the inbox.

4. Bigger MAF, that standard thing looks way to small, maybe Z30 or whatever is the best/easiest/available. Maybe mod the housing on the origanal sensor?

The unknown factors are the still standard jets, FPR and fuel pump. The FPR gauge stays at the same spot at full tilt.

Maybe upgrade the T28 to a GTRS, bigger fuel system, a nice loud vent to atmosphere BOF

I don't want to run all the standard parts at 100% utilization, a little paranoid that way

Lots of meters to monitor everything : Fuel presure, boost, EGT etc.

Whenever I look at some of the overseas forums you see a lot of money spend on brand names cosmetic parts... not my intention to have a show car, just a reliable car with exceptable fuel consumption if I by chance want to cruise at legal speed... and a 200+ rwkw monster when I am in a hurry... (as usual )
_________________

The correct 3" downpipe will help a fair bit

I use smallish very efficient intercoolers you will not find slabs of core across the front of my cars.

Can I say BMC CDA this is a very underrated piece of equipment. You will not find airfilters sucking up hot air on my cars either.

Without daughterboards and such you are stuck with the stock maf. I can machine a bigger housing for the blade and adjust the fuelling with a piggyback.

The Stock fuel rail and FPR will work for the power level you are looking at the stock fuel pump is a piece of garbage I suggest a Walbro.

You will not see 200wkw with the stock turbo the GTir turbo can just barely sustain 1Bar AT THIS ALTITUDE which will give you around 180wkw.

I am not a fan of screwing a small turbo to death to try and squeeze the last bit of boost out of it. Rather get the correct size turbo for the job.

A set of cams with verniers and springs will change the above picture a fair bit and you should see close on 200wkw at 1bar.

johansx · Post by **johansx** » Mon Dec 04, 2006 9:58 pm

The Calibrator wrote:
The correct 3" downpipe will help a fair bit
Was thinking about the Rezlo unit...

I use smallish very efficient intercoolers you will not find slabs of core across the front of my cars.
But a BIG cooler with a brand name painted in black all over the silver core looks nice

Can I say BMC CDA this is a very underrated piece of equipment. You will not find airfilters sucking up hot air on my cars either.
Great minds think alike

Without daughterboards and such you are stuck with the stock maf. I can machine a bigger housing for the blade and adjust the fuelling with a piggyback.
Jip, my idea as well. So what about the Unichip ... Keep, dump?

The Stock fuel rail and FPR will work for the power level you are looking at the stock fuel pump is a piece of garbage I suggest a Walbro.
Walbro I like

You will not see 200wkw with the stock turbo the GTir turbo can just barely sustain 1Bar AT THIS ALTITUDE which will give you around 180wkw.
Ball bearing without to much lag.... as long as it fits the current X-Force and down pipe... My current T28 runs at 1 bar.

I am not a fan of screwing a small turbo to death to try and squeeze the last bit of boost out of it. Rather get the correct size turbo for the job.
I would like a numberplate that reads "200SX T4 * GP" or something simular ...

A set of cams with verniers and springs will change the above picture a fair bit and you should see close on 200wkw at 1bar.

Are the injectors still ok? What if I get silly and want to up the power to say 300rwkw? How many of the current add-ons will I need to upgrade?

Maybe I should visit you early in the new year and sort out the details

The Calibrator · Post by **The Calibrator** » Tue Dec 05, 2006 5:55 am

Was thinking about the Rezlo unit

Thats a start but I have a better design.

johansx · Post by **johansx** » Tue Dec 05, 2006 12:19 pm

Think we should carry on with this off-line. Will contact you soon.

ChemCool · Post by **ChemCool** » Tue Dec 05, 2006 8:23 pm

Johansx, I came accross this quoted paragraph and thought it might be holding sence? Since after you gas flowed the head - you experience power loss. Here it is:

Proper gas-flowing of the cylinder head. A lot of cylinder heads out there flow more air in the wrong direction than they can flow in the right direction. Most people who gasflow cylinder heads don't even realise that they are making it easier for the gasses to also flow well in the wrong direction! Remember that the main problem is that the exhaust gasses flow into the intake port during the increased overlap period. We can put you in touch with people who can do special things to a cylinder head so that it is difficult for the exhaust gasses to pop out through the intake port in the camshafts' overlap period. There's a whole science behind optimising the head to make it "cam-friendly", and usually there is a substantial improvement in the low speed range if the cylinder head is flowed properly, by a person who knows what directional flowing is about. Note that it is easy - even for experienced "port grinders" - to completely ruin the reverse-flow characteristics of your cylinder head.

johansx · Post by **johansx** » Tue Dec 05, 2006 9:10 pm

Nice quote, agree mostly. I doubt however is Mause who has done lots and lots Sr20 heads will stuff up this one... So, cams and better airflow into the cylinders will probably sort this sucker once and for all. However, I still believe there is another problem, like cam timing or something silly...

Phinx · Post by **Phinx** » Tue Dec 05, 2006 9:10 pm

Im planning on getting CA18de Cams soon...

Hi Calibrator do you think its a good Idea to use regrinds on ca18det? I know it not a good idea over all. Did your friend get HKS units for his?