Standard valve springs, how much can they handle

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motomenace
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Re: Standard valve springs, how much can they handle

Postby motomenace » Sat May 18, 2013 2:50 pm

Exactly, i want More mid range power, hence why im not going super aggressive cams.

The tracks i run on are tight and short so i want mid range torque, having and engine that revs to 9000rpm on these tracks would be totally pointless.

I'm going 6 speed box and 4.3 diff as well, possibly 4.44. will do some testing. I want to stay with hla's as i want to keep the original design of the NA model.
As my aim is approx 110kw atw hlas will do that easily.

As the car is with 95kw atw im down to 1.10's at wake, and it will do a 1.09. but just want to be a little closer to the front guys!

Cheers

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Re: Standard valve springs, how much can they handle

Postby manga_blue » Sat May 18, 2013 3:37 pm

Another roadblock for you ... :roll: Depending on the age of your engine the HLAs may be getting old and tired too. Putting in higher lift cams may send them over the edge, as they did with mine. This is the time to make a choice between new HLAs and new solids, before you buy cams.

Everyone says new HLAs for track work need to be genuine Mazda or Kia, neither of which I've found yet at a reasonable price. Also speak to Wozzah about oil gallery mods to help HLAs work a bit better.

Mazdaspeed solids (from MiataRoadster I think) are the popular choice if you go that way, once again better and much cheaper than Supertechs. Valve lash caps can be from MiataRoadster too (cheaper) or locally made by PrecisionShims in Melbourne (a bit dearer but much more convenient). NB: valve stem top to collett dimension is important when ordering lash caps locally.
’95 NA8

motomenace
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Re: Standard valve springs, how much can they handle

Postby motomenace » Sat May 18, 2013 4:07 pm

If there that bad,

im going to throw cams straight in, not worry about springs or anything. If there that brittle id rather not bother engineering it. Ill put new lash caps on and run it till it drops a valve. If it doesnt make power, then bad luck for me lol. The head is brand new and everything was checked by my head shop, seat pressures everything all within spec. Plus im lazy and really cant be bothered changing everything for such small gains. The cams im choosing arent aggressive at all and as the cam shop said, "if the stock stuff cant handle it then there sh*t"!!

Then when the engine is destroyed, ill finish building the nb i have in the shed already with full cage, and throw a turbo on it.
Hell of alot easier, see how we go.

Cant see the point in spending 500 for the cams, then 300 for springs 300 for lifters etc. The head only had 60k on it anyway and was in an auto car, so never seen a hard life. It revs to 8k as it is anyway, im not going huge lift so rather spend the $500 on cams and hope for the best. Our turbo car had 180k but had a different engine at some stage, big cams and never missed a beat. Ill take my chances i think!!

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Re: Standard valve springs, how much can they handle

Postby project.r.racing » Sat May 18, 2013 6:33 pm

sailaholic wrote:Fair bit of cost going solids.
Cams can change engine performance where you want it, that is not always increasing rpm range.

Sent from my GT-I9100 using Tapatalk 2
Well aware. Is the OP?

motomenace wrote:Exactly, i want More mid range power, hence why im not going super aggressive cams.

The tracks i run on are tight and short so i want mid range torque, having and engine that revs to 9000rpm on these tracks would be totally pointless.

I'm going 6 speed box and 4.3 diff as well, possibly 4.44. will do some testing. I want to stay with hla's as i want to keep the original design of the NA model.
As my aim is approx 110kw atw hlas will do that easily.

As the car is with 95kw atw im down to 1.10's at wake, and it will do a 1.09. but just want to be a little closer to the front guys!

Cheers
Not sure if you have done much research into camshafts. But if you are aiming for increased torque, then adding lots of duration and very little lift like you are isn't the way to find it. Especially from the specs provided in the first post. You will get an increase in torque, but the specs read more high end breathing thsan anything.

Less duration and increased lift is what you need to be chasing. And you ain't gonna get that from any HLA friendly camshaft.

I'd suggest talking to another camshaft company about what your goals are before you pass over your cash. Sometime people will tell you anything you wanna here to get you to pass over the cash quickly.

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Re: Standard valve springs, how much can they handle

Postby motomenace » Sat May 18, 2013 6:51 pm

Hence why ill run cam gears and play with timing to get what is needed.

Your not listening, i only what marginal increases!! If i simply put an exhaust cam as an inlet ill nearly achieve what im aiming for, but for 500 for a pair ill be happy with 5-10hp,

There's only two corners im aiming to improve to get a slightly better run down the straights.

Ill post a vid of me running side by side another na, with massive cams, 6 speed and 4.3s down the straight at wakey. My motor already makes very good torque but want a little more. The 6 speed and 4.3 will also help make use of it.

From 26 sec into the vid you will see a black and white car with a wing. Thats the car mentioned above. It has about 120 to 125kw atw
You can hear it buzzing at high rpm but doesn't seem to help it!

http://www.youtube.com/watch?v=csDhzzytIh0

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Re: Standard valve springs, how much can they handle

Postby project.r.racing » Sat May 18, 2013 7:13 pm

motomenace wrote:Hence why ill run cam gears and play with timing to get what is needed.

Your not listening, i only what marginal increases!! If i simply put an exhaust cam as an inlet ill nearly achieve what im aiming for, but for 500 for a pair ill be happy with 5-10hp,
I am listening (well reading really) and it isn't making any real world application sense.

That power increase you just quoted wont be in the middle of the rev range which is your goal, it'll be at high rpm with the camshaft specs you suggest. No good quoting power figure from other cars that have different power delivery goals than yours.

If you can put a near free exhaust cam with $50 spent relocating the dowel, then why spend $500 on camshafts to get same result?

Just keep the camshafts you got and use the cam gears to decrease the overlap. Don't waste money counterproductive things.

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Re: Standard valve springs, how much can they handle

Postby motomenace » Sat May 18, 2013 7:54 pm

Thanks for your input but im not asking what cams to use.

Im asking if stock springs can support, got my answer which was probably not!!

So now knowing that ill take my chances, and wont expect it to last. If they do then yay :)

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Re: Standard valve springs, how much can they handle

Postby NitroDann » Sat May 18, 2013 8:55 pm

I have a fair idea that you do not really understand how this all works fully.

If the car in the video has 125kw, and you have 95kw then his car was running on 3 cylinders.

Lets start with this, you do not want more torque, you want more torque AND hence horsepower through the midrange.

It makes no difference how much torque you have if that white car really had 125kw and you 95 he would have left you like you were standing still.

Its all about torque to the wheels which comes down to hp and gearing.

You dont seem to know exactly what you want, you need to determine at what rpm you want more horsepower and then work towards that.

Sounds like you want more horsepower between 4500 and your current redline which only means more lift or more compression, and your HLAs wont let you do that.

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Re: Standard valve springs, how much can they handle

Postby motomenace » Sat May 18, 2013 9:09 pm

That white car even uses the same dyno!!

I run a 5 speed and 4.11. Ive had heaps of people say that my car must make way more power than what im saying. I even have the dyno sheet to proove and the 95kwatw was on manias dyno. so prob has 80kw lol

Since i have had the car its never missed a beat and finished every race. Never had a dnf. Never had decent tyres on it always second hand sh*t.

Where i want my power is from the fishook, for the run down the back straight, and turn 2. If i leave everything as and put a 6 speed will probably acheive what i'm after.

I have rebuilt the motor and done head porting (in the back shed) shaved the head (not tellin how much told on here couldn't be done) head shop said it can and soo it is. I can even run the stock ecu on this set up but loose approx 80nm compared to the wolf 3d
all my problems could be solved with a turbo, but the rules in the classes would rule me out of too many classes :s yet i do an NB and thats ok!! ??


Mayby its just the driver making the car quick lol :/ me not think so!

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Re: Standard valve springs, how much can they handle

Postby motomenace » Sat May 18, 2013 9:11 pm

Oh and with the head shave dont think ill be able to go much more than the 9mm lift anyway :/
Not sure how close the valve to pistons will be.

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Re: Standard valve springs, how much can they handle

Postby motomenace » Sat May 18, 2013 9:50 pm

DYNO Sheet
https://www.facebook.com/photo.php?fbid ... =3&theater

After 20min run in and a few tuning runs.

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Re: Standard valve springs, how much can they handle

Postby noobee » Sat May 18, 2013 10:48 pm

looks like you are increasing lift and duration by a similar percentage,so acceleration/deceleration of valves should be similar to stock.
Mick

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Re: Standard valve springs, how much can they handle

Postby motomenace » Sun May 19, 2013 12:40 am

Oh and dan, that red car that i over took at the start at turn 3 has about 130kw

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Re: Standard valve springs, how much can they handle

Postby NitroDann » Sun May 19, 2013 1:19 am

Sure it does.



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Re: Standard valve springs, how much can they handle

Postby project.r.racing » Sun May 19, 2013 7:58 am

motomenace wrote:Oh and with the head shave dont think ill be able to go much more than the 9mm lift anyway :/
Not sure how close the valve to pistons will be.
0.1-0.2mm off the head wont make next to no difference to compression or height. I have 256dx9mm in/ex toda cams (36mm base circle) in my BP-05 and it is still non interference. Which is really just a 0.11mm increase in lift on the ex side anyways.


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