NA8C Race car issues, help please

[Juffa]

How is the cooling system, ie standard radiator, or aftermarket. Is the under engine tray still in place, I asked this because the underengine tray does greatly influence the amount of air going through the radiator. has the timing been adjusted due to the new cams?

Can running pig rich affect the engine temp?

J

[manga_blue]

Tried looking at the timing through the rev range with a bit of load? Retarded timing will cause overheating, it will be especially evident in the headers and exhaust.

Might even be worth taking the initial setting up to 16 to see if it makes any difference.

[green_comet]

The AFC Neo should be able to fix you air/fuel ratio. I have a Jaycar DFA in my car and its works great.

As for cooling I would upgrade you radiator, replace the waterpump, and repalce the thermostat. I would even look at running an oil cooler setup, and getting you headers HPC coated. This should all really lower your temps.

Its funny that your car is running soo rich, it could be the o2 sensor, or maybe the MAF is stuffed.

[Fatty]

overheating is usually only an issue with forced induction i thought ? maybe your radiator is clogged up ? are the fins all straight? you may need to spend some time with a set of needle nose pliers straightenning all the fins... i dunno i'm just throwing a few ideas at ya.

also as green-comet mentioned the dfa's are great for correcting your fuel ratios. i'm not surprised your ratios are out , since you've changed the cams. the dfa's have heaps more tuning points than the apexi units so they can do much finer control over a a wider range of load points. (they are heaps cheaper too, but you need to build it yourself as it comes in kit form) altho if you've already bought the apexi just stick with that i guess.

[Matty]

I would suspect the radiator of being past it...

I'd also recommend getting a proper programmable ECU. Adjusting the ignition timing will be very important (as important as AFR) to getting good performance out of the cams.

re in-car heat, check the rubber shift boots under the centre console. If they're cracked, a lot of hot air gets in.

[ampz]

Has the interior carpet and insulation been stripped out to save weight?

[CT]

Nah, timing is 28 degrees all in. Have just replaced the maf, going on the dyno wednesday.
Overheating is a big issue though, do they overheat standard or do I have an issue?
Is there an easy radiator upgrade? Don't say PWR.

You need to rethink your car's setup. A PWR 40mm is certainly the start to fix your cooling issues, you may also have to consider a coolant re-route, higher pressure radiator cap and better ducting. NA race cars do have cooling issues that road cars will never see.

Then, you need a real ECU, buy something that is fully customisable otherwise you are wasting your time. I make no apologies to anyone who things a cheap add on from jaycar or a jap interceptor can match a properly programmable ECU - it will not - especially not in a race car. My old NA MX5 made 122rwkw with a $1000 EMS stinger. It's basic but much better than an interceptor and will handle an na engine easily. If you want a better unit, I (and about 30 other racers) can heartily recommend the Haltech E8. It is an excellent unit to which you can add wide bands, boost controllers and heaps of other functionality. Plus, you can ditch the MAF and tune on throttle position which is how it should be setup for an na race car.

There is no way a stock ECU will properly fuel and time large cams - 250deg is about their limit. I used to run 292deg and it required adjustable cam gears to properly dial in and tune - not to mention a whole other world of modifications.

[CT]

Brand is irrelevant, just get a decent sized alloy radiator and use a thermostat unless you are running an electric pump.

Seriously, you are kidding yourself if you think you can get a reliable race car without decent aftermarket engine management. It is the single most important part of a reliable car. If you are at Phillip Island this weekend (and I assume that's the enduro you are talking about), come and look at the MX5 race cars that are there - there will be plenty of us.

122rwkw was in shootout mode on dyno dynamics. It was a fairly expensive, race motor designed to rev to 9000rpm.

[Fatty]

[ I make no apologies to anyone who things a cheap add on from jaycar or a jap interceptor can match a properly programmable ECU - it will not .

i don't think i've ever said that. it is a good option for cheapskates like me tho .

[neil d]

[quote="CT"]Brand is irrelevant, just get a decent sized alloy radiator and use a thermostat unless you are running an electric pump.

Seriously, you are kidding yourself if you think you can get a reliable race car without decent aftermarket engine management. It is the single most important part of a reliable car. If you are at Phillip Island this weekend (and I assume that's the enduro you are talking about), come and look at the MX5 race cars that are there - there will be plenty of us.

quote]

I agree with Chris!

You need a better engine management and to get a decent radiator. Then look for more power. Until you have this sorted you are wasting your time chasing more power.

Come and have a chat at the Island as coming from QLD and racing in 35deg heat we know how to keep them cool.

Neil

[Fatty]

post removed - off topic

[CT]

The car will be competing in the Alpine Rally, not at PI. So rather than just doing a few laps it stays on stage for up to 1hr.
I have added water wetter to the cooling system and am runnig both fans all the time.
Does the BP have a water bleed on it? At the moment I am bleeding the air out with the heater hoses.
Can you be a little more specific about the mods done to achieve that kind of power leve. Eg cam duration comp ratio billet rods etc.

At phillip island this weekend, there will be 58 sports car including 15 +MX5s racing in a one hour enduro. That's just a little harder on an engine than "staying on stage" for up to an hour.

[neil d]

The car will be competing in the Alpine Rally, not at PI. So rather than just doing a few laps it stays on stage for up to 1hr.
I have added water wetter to the cooling system and am runnig both fans all the time.
Does the BP have a water bleed on it? At the moment I am bleeding the air out with the heater hoses.
Can you be a little more specific about the mods done to achieve that kind of power leve. Eg cam duration comp ratio billet rods etc.

At phillip island this weekend, there will be 58 sports car including 15 +MX5s racing in a one hour enduro. That's just a little harder on an engine than "staying on stage" for up to an hour.

LOL

[fattima]

At phillip island this weekend, there will be 58 sports car including 15 +MX5s racing in a one hour enduro. That's just a little harder on an engine than \"staying on stage\" for up to an hour. Rolling Eyes

Do an Alpine and you may want to revisit that comment

Hey Mal I presume this is your car, took the pic at the Strahbogie stages earlier this year. Good luck with the Alpine.

[Ted]

Good Luck in the Alpine, definitely on my to-do list. Even have the car sitting in the garage to have a play one day, but those long stages in the Alpine will require a pretty strong car.

One of the problems I used to have with my old NA was overheating when pushed hard, esp uphill. I always put it down to the design of newer cars preferring to go in a straight line, and lack of airflow when cocked sideways a lot. Unlike drifting, rallying just has lots of kms. My car used to run hot in Qld, but put up with 52km in one stage with no problems in Tassie. A new radiator did help somewhat, as did making sure there was nothing in the nostril (no lights, grilles, number plates etc).