How to select cams?

**Scottie** · 30-07-2010, 15:21

Originally Posted by martinbattye

555's should max out at about 1.1bar on 2871r (the 52trim varient) which is about 340-350hp

I'm not sure what trim I have, but it's the 0.64 version.

At 90% duty cycle it was 1.45 bar, and 360bhp (fly) on a dyno dynamics rollers, although I'd let 7 psi out of each rear tyre and had 3 men in the boot, so the real figure was a little higher due to the increased drag.

This is spot on for the many cars I've seen mapped and rolling roaded on 555's over the last 10 years. About 370bhp is the max of 555's at standard fuel pressure with origianl FRP but walbro etc.

Do you mean 340whp or flywheel bhp?

**piman2k** · 30-07-2010, 15:45

Thanks for all your help Scottie, I fully intend to get it in and enjoy it.

The comment about the RB26DETT, you can land an engine, turbos, loom and ancilaries for about £3.5k these days. Okay you need a box and prop conversion but when you think how much a 'lined and stroked SR20 would be it makes sense.

Problem is, then modding an RB26. I quite like the idea of building up a savage SR20 but this one will be great enough. I think I will look into the 260 or 256 cams and see what I can do.

Oh, running 740's btw!

Thanks man!

**crouchy** · 30-07-2010, 16:27

Tomei 256 cams are real cheap from www.frsport.com thats what i will be running in mine with a 2871r

**piman2k** · 30-07-2010, 17:03

Thanks crouchy, I will look at them.

I'm thinking that this would be a pretty comprehensive head spec for parts:

Tomei 256/260 Pon Cams - $450
Tomei RAS - $80
Brian Crower BC0200 Springs/Titanium Retainers - $236
Brian Crower 3200 Stainless Intake Valves - $152
Brian Crower 3207 Stainless Exhaust Valves - $152
Nissan Valve Stem Seals (8I/8E) - $80

That's like $1260 shipped (£804) which is a lot of money, plus someone to properly build it up and do the machine work.

And that doesn't include:

New Spray Bars
Hydraulic Tappets
Labour

What's this I read about phosphor valve guides and Bery rings?

**OdEssA** · 30-07-2010, 17:03

I have the same turbo like you and when i uprated my cams i asked my tuner (APT) and they told me to go for the Tomei Poncams 260° over the Tomei Procams 256°

**piman2k** · 30-07-2010, 17:04

Thanks mate, that's SOUND advice as well. It seems I'll be onto a winner either with the 256 or 260's.

**sideways14a** · 30-07-2010, 17:07

I didnt bother with chopping the valves out, i just got them all 3 angle cut ect.. The gauge said they were all the right size as per FSM and none were banana shaped.
I wouldn't change them unless they were shagged, but you would want some head cleaning up / machining factored in.
Valve stem oil seals were a fook on for me, i went to a local motor factors and the spack gave me 16 of them all the same size (exhaust valves) and the SR runs different sizes intake and exhaust

I think i got my BC cams/springs and retainers for less than your retainer/springs and tomie cams combined.

**Scottie** · 31-07-2010, 11:39

Agree, you don't need new valves unles there is a problem.

Just clean the spray bars - fairly cheap i seem to recall to have ti done professionally.

I guess you'd need new rockers with new cams?

**PallominnoX** · 31-07-2010, 14:32

Just really curious, how would 256's or even an exhaust cam on the inlet of a CA18DET affect idle? I really like the smooth idle i have now and i'd rather not give it up for more lag, crappy idle and somewhat more power.

**Aj82** · 31-07-2010, 15:56

I would personally go 260's mate, should give good all round performance and what you are after with a good map.
Speak to Mazworx aswell, i got a cracking deal with them but i did spend nearly 2k on valvetrain with them! lol

Cheers Aj

**piman2k** · 31-07-2010, 15:57

I'm not gonna waste their time yet mate as they've been good to me so far, but this winter I will give them a call. Nice one mate

260's I think it is.

**Aj82** · 31-07-2010, 16:29

Ah right my bad, forgot you werent looking to buy just yet. I would buy the cams soonish though as they may go up in price soon due to the economy apparantly getting better.

Cheers Aj

**piman2k** · 31-07-2010, 16:36

Haha you've got to be kidding. I need still another £600 just to get my car moving, and I've got a spoiler to buy and a Punto to insure!

**martinbattye** · 03-08-2010, 12:58

Originally Posted by Scottie

I'm not sure what trim I have, but it's the 0.64 version.

At 90% duty cycle it was 1.45 bar, and 360bhp (fly) on a dyno dynamics rollers, although I'd let 7 psi out of each rear tyre and had 3 men in the boot, so the real figure was a little higher due to the increased drag.

This is spot on for the many cars I've seen mapped and rolling roaded on 555's over the last 10 years. About 370bhp is the max of 555's at standard fuel pressure with origianl FRP but walbro etc.

Do you mean 340whp or flywheel bhp?

i mean by injector maxing out that there is no more flow from above 85% duty..

what was your wheel hp..?

**200sxct** · 06-08-2010, 14:56

Originally Posted by Sideways14a

I think i got my BC cams/springs and retainers for less than your retainer/springs and tomie cams combined.

Yes my BC 264's from FR sport cost me about £200 delivered including tax! THe BC springs worked out to be less than £60 plus delivery!!

They work really well together with the 3071r and H-dev manifold. Full Boost comfortably before 4000, 15psi by 3200 and holds power to 7000+rmp even with 2.5" mongoose

(now changed) . Idle is fairly smooth too.

The only major difference I can see is a bout 500+ rpm extra rev band than the poncams, which seem to drop off around the 6 to 6.5k mark. I can't see any point in going for the poncams given the price and perfomance of these cams??

**bahis** · 06-08-2010, 15:07

I ordered the BC cams a few weeks ago from FRSport, but they are out of stock and won't get any until the 3rd week of august...

**200sxct** · 06-08-2010, 15:31

THey were out of stock when I ordered them, they quoted about 3 weeks and they arrived after just under 2 weeks.

Fingers crossed.

**sideways14a** · 06-08-2010, 16:33

Just get em from BC direct, thats what i did.
This is what i meant in another thread about cheep parts, I got a great deal from Mazworxs and BC for the bottom and top end parts i needed. Was loads cheaper than if i had went with others from over here and they are excellent manufacturers.

Looking forward to the 264's, a good cam for 400-500+

**piman2k** · 16-08-2010, 21:05

Right, update

I've decided to delay my car a few more months. It's almost September and it's not really finished, I'm not going to use it in winter so I don't see the point in rushing. So I'm going to build a better head with something similar to the above spec.

This opens up the opportunity to have a look at that Head Gasket if required. So, is moving from my 1.6 to a 1.2 really going to affect me a lot for the better?

Thanks

Ryan

**Damo** · 16-08-2010, 23:48

it will give you a little bit better low end to mid range power

Thread: How to select cams?

Thread Tools

Posting Permissions