Standard valve springs, how much can they handle

[motomenace]

haha dan,

You are a true idiot lol.

The red one is a 1950l same as manias goldie, you obviously have no idea how power on a track works!!
Why do our cars beat 300kw commies and things then???
Comes down to useable power on a track, those cars on long straights will be a different story!!

Goldie manias car has 130kw, that red one is the same as goldie and makes the same power. That white one makes about 10kw less.

Ashame u know everything, u might learn something!! But hang on i bet u would say a huge turbo say t70 on tight track that makes 300kw at 8000rpm at the wheels will beat a car with 200kw and say a t28 or t25.??

Ill put the cams in and see what the lap times tell me as to if it works or not.
I know what the cams will do that i have choosen, just wanted to know what the standard valve springs would support!! Now i know ill be pushing them to their limits if not past their limits.

0.1 0.2 head shave?? Yeah its a little bit more than that lol.

[motomenace]

Ashame u know everything, u might learn something!! But hang on i bet u would say a huge turbo say t70 on tight track that makes 300kw at 8000rpm at the wheels will beat a car with 200kw and say a t28 or t25.??

the same car with different setups!

[manga_blue]

Just going back to the original question ... I didn't realise you had such a low kms motor. Everything I've said was based around the assumption that yours was like every other NA8 in the country, with about 180,000kms or more on it. That makes a big difference.

I've heard that new standard NA8 valve springs are good for about 7500prm, i.e. a little slower than NA6. It reflects the fact that Mazda redlined NA8s at 7200rpm and specified softer spring rates. When I first dynoed my NA8 it was bog stock with 160,000kms on it. Valve bounce started to appear a bit before 6700rpm and it was pretty terminal by redline. If you assumed linear decline in valve spring rate with mileage then, just using my one example, yours could be good for 7500-(7500-6700)*60000/160000 = 7200rpm. It's more likely that they'd hold their rate for a while then decline rapidly. (Is there a metallurgist in the house?) Anyway, that might mean yours are good for 7300-7400ish. The springs I use now are good for 8000+rpm and cost me $125, so they're cheap but you need to factor in a head gasket, fluids and a few hours work to fit them.

Likewise I've heard new OEM HLAs are good for 7800rpm. Mine have almost 190,000 kms on them and they can't hold pressure effectively with shift points above 7000 rpm for more than a lap or two, even with increased oil supply. I tend to rest the car for a lap then go for it for a lap. Again, assuming linear degradation, yours are OK for 7800-(7800-7000)*60000/190000 = 7550rpm. The same comments about non-linear degradation would apply, so they could easily be good enough for your 7700.

I'd say if you have the cams then just whack them in and see what happens.

[NitroDann]

You do not need to pull the head off to hang valve springs AFAIK there is a method involving compressed air. I've not done it myself however.


To motomenace.

In the video you and the white car accelerate through a few gears on straights. he doesn't have 40 percent more power.

You don't understand how torque /power works if you truly believe that.

Dann

[motomenace]

Thanks magna,

I have a mate at kia who can get me new lifters at cost!!
Yeah, in the last race i done last mra i turned the rev limiter off and at about 7500 the power flattened off.
I have another head here which has done approx 80k. I may as well just throw the cams in the motor i have now, (im lazy couldnt be bothered changing the springs in the car atm) head on can be done but seriously couldn't be bothered with rope down the spark plug stuffing around etc. That motor is brand new too so really don't wana take the head off. If i blow it ill just rebuild the other head and do springs etc, put it together properly than sell the car and finish the nb. But i also have an r31 (drift project with rb30/26) so not sure what i wana do yet. nb or r31 mmm

Dan the gearing on the white thing is what lets it down!!, if we were at Bathurst or the island even SMP gp circuit, he would leave me for dead!! as his car will be easier to keep in his power band. Coming out of the tighter corners he cant jump on the power like mine, and my tyres were much better on the day!! Same story as the red thing he had trededs on that day, i had full slicks.
The other thing was all the dynoing was done with run in oil in it and only had about 30 mins of run time before we done the final run. I didn't change the oil after either (cbf) so raced it a total of 60 laps on the run in oil too. Now with some full synthetic 10w60 track oil itl go better.. i guess.
Torque is the motors turning force to the rear wheels, power is the measure of work the motor can do in a period of time!!
More torque means the car can turn the wheels easier however more power will result in the motor being able to get more work done, hence you hear his thing revving its ringer out near the ends of the straight but its all too late!! See how quick he gets past me down the main straight once his car can unwind!!

[motomenace]

Also i have used compressed air to do recalls on chrysler 300cc valve collets.
Basically use a leak down tester and wind the motor till the valves close on the cylynder u want to remove the collets from and the compressed air will hold the valve closed!

Can use rope down the plug hole and wind over to tdc until the rope compresses the valves closed. All a pin and fidly but probably still easier than takiing the head off

[manga_blue]

I have a mate at kia who can get me new lifters at cost!!

I'd appreciate a pm about that if you do get a price.

[motomenace]

HAHA,

mmm im not sure hed appreciate doing special prices for everyone :/, he still needs to make some money!!
Im sure he may be able to do a reasonable discounted price though!!

Hes a very good friend and has been for years!!, and i don't normally get many parts from him. As a guide though, he priced me a 4.7 diff with pinion crown wheel and bearings for $350 brand new!! so im sure lifters would be pretty cheap!

[NitroDann]

Ive watched your youtube video enough times to know that when you are both neck and neck accelerating in a straight line he looks to have about a 10hp advantage, maybe 15, and you clearly have better tyres and/or racecraft.

if you are both accelerating in a straight line, at full throttle, equal exit speed and he had 40% more power it matters not what track you are at, he would stomp you on the way to the next corner.

Dann

[little decks]

Bottom line here is and seems to always be... Dyno sheets lie... stop watches don't. You can argue about gearing and wheel diameters all day but a genuine 45% difference in power is huge, you aren't going to need a long straight to demonstrate that.

[motomenace]

So, we all use the same dyno,

Which everyone says tells lies (higher than normal readings)

It makes no difference as i use the same dyno each time so im comparing apples to apples.

If i get 100 to 110kw after cams and a reutune im happy.

The other car u can hear screaming, redline at 8000+ was sold in queensland stating 120kw+ and after a retune in syd claims to be the same??

Dont really care, as i know what im aiming for and cams will achive that, ;). Seems people cant hack that a near stock motor is nearly cracking the 9's and all done in my back shed costing me less than 8k to build the whole car!!

This thread is way off topic as all i needed to know was what the VALVE SPRINGS would take, i didnt ask for peoples opinions on power gains!!
Cheers

[NitroDann]

Dont really care, as i know what im aiming for and cams will achive that, ;). Seems people cant hack that a near stock motor is nearly cracking the 9's and all done in my back shed costing me less than 8k to build the whole car!!

yes cams will but what you tell us you want will not be achieved by the cams you are choosing.

Im going to do 5s for 5 grand as a personal challenge, we will see, and you ca save thi sand rub it in when i fail

Dann

[motomenace]

Im going to do 5s for 5 grand as a personal challenge, we will see, and you ca save thi sand rub it in when i fail

If you are, just running a 1.6 with a turbo will easily achieve that goal!!

Im all for budget racing, turboing a 5 can be done easy and well less that 5k. I done a charde years ago, 1.3 with a manifold i made at home out of steam pipe. I ran an ihi rhb5 turbo and made 130kw atw Cost me less than 2k to do the turbo setup. Biggest expense was the ecu, which at that time was a microtec. It ran a 13.1 at eastern creek .. Stock motor just dowled the sleeves (alloy block cast sleeves).

We need to proove that spending ridiculous money isnt the answer to going quick!!. However we dont pay labour! which for most is the biggest expense!

All the best

P.s Im not the person to gloat over someones demise either. I think its a very reasonable challenge and very acheiveable. How long it will go?? well who cares!! In saying that with new bearings and some chrome rings, arp rod bolts should see it go forever (providing a good tune is done!)

[NitroDann]

5k for EVERYTHING including purchasing the car.

Dann

[motomenace]

Yep,

i got my car for 2k, with a 1.8 , just couldn't/cant be regod. Eunos roadster import.
Was near immaculate, and only had 58,000ks was an auto but came with all the stuff to make it a manual.

Sold all the interior etc and the car paid for its self. Wheels and tyres were my biggest expense!

Matt