CAMS?

Discussion and technical advice for 84-89 AW10 & AW11 MR2. 3A-LU, 4A-GE, 4A-GZE.

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gordy.r

CAMS?

Post by gordy.r »

Just (another) quick one, the cars in getting a full service (timing belt, fanbelt and clutch main header bottle/tank changed aswell due to a leak) and while it was in ive had tuning thoughts running through my head......
What is the best or highest cam shaft i could fit to my n/a without having to modify anything else???
And what would the performance benifits be?
Icsunonove
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Re: CAMS?

Post by Icsunonove »

These are what they use in Formula Atlantic:

13501-AE881-D Intake Camshaft $ 720.00
13502-AE881-D Exhaust Camshaft $ 720.00

Rather pricey! :shock:
LimeyMk1
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Re: CAMS?

Post by LimeyMk1 »

:lol: Tom those cams would tear his head apart if it wasn't modified, they've got a stupid amount of lift IIRC.

TED components lists 10.7mm lift needing machining of the head to remove metal that would otherwise obstruct the lobe rotation. High duration doesn't need any mods to the head.

To get the best out of any uprated cam will need adjustment to the fueling and a rolling road tune.

Richard at TED told me that a 8.6mm lift/262 duration could be run on a stock ECU but as above would really benefit from proper tuning.

Performance benefits in a nutshell: High lift gives increased low rev torque and high duration, high rev bhp increases (at the expense of low rev power). That's what I remember anyhoo.
gordy.r

Re: CAMS?

Post by gordy.r »

thanxs, its mainly low -mid rev torque im looking for, i feel the mk1 n/a needs a little kick sometimes to help it accelerate upto 4200rpm.
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Re: CAMS?

Post by Icsunonove »

:oops: Sorry Chris and Gordy, I was sort of joking. These cams can't be used for various reasons...
LimeyMk1
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Re: CAMS?

Post by LimeyMk1 »

:lol: Thought you might be :wink:
luthor1
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Re: CAMS?

Post by luthor1 »

decent cam for MR2 would be anything over 10mm lift, and 270-280 degress duration.

Can modify celica solid lifters to save £££

Speak to Roger at Sabre Heads, he has a custom profile listed with Piper Cams. The silly little lift ones are just not worth it. The MR2 Mk1 cylinder head flows enough air for around 180-190bhp, then you put the silly intake and silly little camshafts on it and it restricts it down to piffling 125ish.

Rogers words not mine, he can make 20v with 200bhp if you like. 180bhp on an NA is realistic with throttle bodies, head work, cams, and decent (DECENT!) Exhaust arrangement.

Unless you are going properly, just don't bother.
juanwond

Re: CAMS?

Post by juanwond »

My setup isss:

HKS 'fastroad' cams
HKS Super powerflow system
Polished/ported head
Magnex Exhaust system

Power is 142bhp@7000 at the wheels after rolling road tuning - no point fitting cams if you're not going to do a proper tune up afterwards.

Should be more to come from this once I've had my Unichip fitted as it's currently on a standard ecu map.

Power is up across the board with more power being produced now by 4000rpm (112bhp) than mine ,when standard, at peak power (109@6600rpm)

Cost:hmm not sure exact as it was a while ago but about £450 for the cams (quite expensive i know, there are cheaper ones) , £250 for the 'Powerflow' (V.noisy induction noise when accelerating hard..sounds like Darth Vader on steroids), about the same for the Magnex and about £100 work on the head, so £800 without fitting for the gear, but i'm sure you could use other components to get similar results for quite a lot less (anybody tried Raw engineering's Trackpack options)....have a look at their website if you're interested...www.rawengineering.co.uk £540 for the kit to take it to a (claimed) 160Bhp...note that's at the dyno *i presume* Not the wheels as i quoted for mine..if true would be pretty close though.

Juan.
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Lauren
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Re: CAMS?

Post by Lauren »

If you want drop in cams... then 256 duration (think they are pretty low lift though) is an option... agree with the others though, when it comes to engine modding you can't really do just one thing in isolation, though in saying that its not a bad place to start.

would think you ought to have at least a unichop so that you can get it mapped if you go lairier than 256 duration.

just out of in interest what is the car going to be used for?
2020 GR Yaris - Circuit Pack :lover:
gordy.r

Re: CAMS?

Post by gordy.r »

cheers guys, i am looking to probably go a lot further with the tuning side of things, was just interested in what was involved, so it looks like i might need to get some head work done if i want a decent cam set up then!

speaking of exhaust set ups, where can i get a 'decent' one that you speak of? i was considering going to longlife for mine. any suggestions on this?

as for what its going to be used for (your going to laugh now), its for general travelling about, going from england - scotland and the occasional trackday! so i cant have a massive petrol guzzling machine, i need a compromise!!! i know, i need another car! :oops:
Last edited by gordy.r on Wed Nov 30, 2005 6:38 pm, edited 1 time in total.
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Lauren
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Re: CAMS?

Post by Lauren »

gordy.r wrote:cheers guys, i am looking to probably go a lot further with the tuning side of things, was just interested in what was involved, so it looks like i might need to get some head work done if i want a decent cam set up then!

speaking of exhaust set ups, where can i get a 'decent' one that you speak of? i was considering going to longlife for mine. any suggestions on this?


magnex/mongoose are pretty good exhaust wise and theres the liftetime guarrantee as well due to them being stainless. Also they are not stupidly loud but will add 'character' to the sound of your car, so about right IMO.
2020 GR Yaris - Circuit Pack :lover:
crazylegs
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Re: CAMS?

Post by crazylegs »

back on the cam front you can go up to about 10.25 lift without the need for under bucket shims but you will have to get the grinder out .IMHO any cam change will need a change to the fueling and a unichip.RR is a must as well.so unless you have a few pennies to throw at it stick with standard.
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Re: CAMS?

Post by LimeyMk1 »

Gordy, I've got a longlife system and it was over £300 for just the back box. Pretty pricey, but I've got it fitted to a Mongoose down pipe. Don't know about gains etc but the overall length/pipe diameter is identical to the goose so should be similar.

Juan what's your cam profile? Must be pretty lairy to neet extra width on the inlet ports!
Last edited by LimeyMk1 on Thu Dec 01, 2005 10:39 am, edited 1 time in total.
luthor1
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Re: CAMS?

Post by luthor1 »

Since Roger @ Sabre Heads works out the back of Janspeed in Salisbury, he suggested making a stainless exhaust manifold using the ideal lengths etc to match the cam profile. Apparently the cams dictate (majorly) the optimum design of the exhaust, and not doing it "right" on such a highly tuned engine (180bhp from a 1.6!!) is just a waste of bhp and mpg.

Unfortunately the one-off cost of this would be around £600. If many people were interested I could probably get them to bring down the unit cost and we could share the development cost among "x" number of people.

I am still interested, (and saving mainly) in my OMEX throttle body/piper cam/sabre head assembly. After a lengthy thread in "modifications" regarding other NA engine options, I have decided to stick with the engine it has and tuning it up stupidly.

My route is extremely expensive unfortunately, the head would be around £500, the cams £400, the throttle bodies including mapping and ECU etc around £1500-2000, then I would need light flywheel and new clutch, the exhaust manifold and connector pipe. Would not expect much change from £4000 once completed, but would be 180bhp at least at the flywheel, probably around 150 at the wheels, maybe more.

Oh, yeah, don't change the cams without changing the mapping... I agree with the others.
juanwond

Re: CAMS?

Post by juanwond »

My cams are 272's good for mid to high power, not so grreat lower down but then the 4age is a naturally high reving unit anyways..least the way i drive it!
:evil:
Juan
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Re: CAMS?

Post by PsychomIKE »

juanwond wrote:Power is 142bhp@7000 at the wheels after rolling road tuning - no point fitting cams if you're not going to do a proper tune up afterwards.

Power is up across the board with more power being produced now by 4000rpm (112bhp) than mine ,when standard, at peak power (109@6600rpm)


Wow, that's a seriously impressive jump in power which, for most of us, is not a lot more than two cams thrown in and a tune up (most guys seem to have a stainless and some sort of induction) - I'm impressed.

What's the car like to drive like that? Streetable? And how much effect has it had on your MPG?

Mike
luthor1
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Re: CAMS?

Post by luthor1 »

272 is perfect duration, but you probably don't have the lift.

If you had the lift, you would have better torque, well better power everywhere. However, as before, with higher lift comes requirement for solid lifters and in some cases head modifications and CERTAINLY fueling alterations.

What CAM make and model are you running? I will pull the numbers
LimeyMk1
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Re: CAMS?

Post by LimeyMk1 »

Re solid lifters

http://www.club4ag.com/faq%20and%20tech ... uning.html

I guess plenty have seen this, but there're always a few who haven't.

£11+vat each from MrT and I've yet to find another source.
luthor1
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Re: CAMS?

Post by luthor1 »

That's cool. Simple and effective!

11+vat each is an absolute bargain?!
juanwond

Re: CAMS?

Post by juanwond »

The car's very driveable on the road, and that's before having the fuelling/ignition mapped properly. Unichip soon, hoping for about 150+ BhpAtw - the timing's just been done at the cams for the moment though no vernier stuff.
The engine pulling smoothly from about 2000rpm - before that's it's a little lumpy though still not a problem around town. From 4000rpm on it just pulls harder and faster for the redline, with a quite pronounced vtec like kick in power and noise when Tvis does it's thing.
You do have to rev it some to get the performance,yesss indeed - as you'd expect it doesn't have as much torque low down as stock (not untill 5000rpm in fact), but it's very noticeably quicker than standard. It'll happily pull away from say a Golf mk2 16v (a standard one anyway!) from about 60mph onwards and it'll hit over 7000rpm in 5th on a decently long (legal) piece of road.
And yes it is low lift (8.1mm i believe) - HKS 272(common exh./intake).
Mileage....believe it or not over 30mpg when driven sensibly (below tvis). So, yes 'silly low lift' cams but works for me! :D ...

Juan.
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