GR Yaris Tegiwa Type-M carbon bonnet

After the rain cover is installed on the engine cover with a vent, the heat dissipation effect is not as expected, and it is meaningless to replace the engine cover. When it rains, the best thing to do is block the vents with fiberboard so the rain doesn't get in (unless you're racing for competitive purposes and don't care about dirt). Therefore, all hoods with ventilation holes should pay attention to the location of the ventilation holes when it rains, where the rain will flow, and whether it will affect the electronic components inside the engine. The vent on the hood of the engine meets rain, and the water flows to the intake manifold, so far no electronics have been affected after I drove in a period of heavy rain. The fact that any electronic component in the car is waterproof to some extent is nothing to worry about, after all, you are not soaking the car in water.

In addition, even if his opening is not as big as GRMN, but I can tell you for sure, this does have a certain heat dissipation effect, as long as you drive at a certain speed, hot air can be smoothly exported, especially when it rains, you can clearly see the windshield there is hot gas generation, which is not a phenomenon under the OEM hood. And the opening is too large, the stability of the vehicle is relatively serious, so it is best to choose the product that has been tested by the wind tunnel will be safer.
 
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After the rain cover is installed on the engine cover with a vent, the heat dissipation effect is not as expected, and it is meaningless to replace the engine cover. When it rains, the best thing to do is block the vents with fiberboard so the rain doesn't get in (unless you're racing for competitive purposes and don't care about dirt). Therefore, all hoods with ventilation holes should pay attention to the location of the ventilation holes when it rains, where the rain will flow, and whether it will affect the electronic components inside the engine. The vent on the hood of the engine meets rain, and the water flows to the intake manifold, so far no electronics have been affected after I drove in a period of heavy rain. The fact that any electronic component in the car is waterproof to some extent is nothing to worry about, after all, you are not soaking the car in water.

In addition, even if his opening is not as big as GRMN, but I can tell you for sure, this does have a certain heat dissipation effect, as long as you drive at a certain speed, hot air can be smoothly exported, especially when it rains, you can clearly see the windshield there is hot gas generation, which is not a phenomenon under the OEM hood. And the opening is too large, the stability of the vehicle is relatively serious, so it is best to choose the product that has been tested by the wind tunnel will be safer.
Ok, if you think the Tegiwa hood works, the most telling data would be the temperature and barometric pressure data.
So you agree with me that water finds its way over time. I don't want any more water from above. If you're driving and everything's hot, that's no problem. But standing and on the trailer already. Had water in the spark plug holes once, no idea how that got there.
Masking the holes with tape is not an option for me.

I also think that Toyota doesn't trust the rain from above. 🤣
 
Had water in the spark plug holes, then you should be checking the tightness of the electronic ignition coils, not blaming the engine cover vents.

I also replied to you above, any form of engine cover with a large number of vents is not suitable for daily street use, such a product is really suitable for the racing field, even if the engine cover has a small number of vents of the car, For example, impreza, mini cooper, BMW M5, etc., also need to pay attention to where the rainwater flows through the vent, not to mention the dirt and water stains in the engine room can be clearly seen after opening the engine cover after rainy driving, but I think most car manufacturers seem to think that a small number of vents are not a problem. As long as your vents don't have an over-the-top design like VARIS.

You do not need to use tape to seal the vent. The product itself provides a shield inside the engine cover that can be locked on the inside of the vent to shield the rain, but the board itself does not have the function of drainage and water guiding like rain cover.
 
This is the detail of carbon fiber, I try to shoot it more clearly, but it is very difficult to shoot well due to equipment and environmental problems, but if you look carefully, you can find a bunch of flaws and uneven places at the joint, if it is the scene will be more obvious
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Ladies and gentlemen, this is a picture taken from the vent, so it should be clear where the rain will flow to, personally, there are no important electronic parts in these locations, so there is no need to worry about failure.

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In addition, the interior of the engine cover can be clearly seen to have a fixed lock point to lock the cover plate, which is very good in a rainstorm, can effectively prevent rain intrusion, and the relative vent has no effect.

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For those of you who are worried about dirt, you can clearly see that the engine room is still clean after 5 hours of rainy driving with the vent open, and there is no dirt problem, so there is no need to worry too much.

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I was looking at buying one, but realised there's nowhere under the bonnet to attached the bonnet stay or bonnet stay clip. How have you got round that? Have you got any close ups of how bad or good the weave quality and finish is (you say it's not good).
Also interested to see what the chicken-wire grill looks like too - does that also look cheap? ,
Last question i promise - when it rains, where does the water run to?
Hey, look at the photo I shared, the type-M has a relative position marker, you just need to punch the hole and move the original oem related items to the past
 
It'll be cheap because it's carbon cloth laid over fibreglass and in doing so it's a lot more difficult to lay the outer cosmetic layer perfectly. Making either prepreg or resin infused full carbon parts you can get much neater seams but the processes and materials are more expensive, you get what you pay for. Given the fact it's 60% of the price of competitor products you can't really hold the cosmetic stuff against it. My Scara wing was over £3k and there's even imperfections in that.

Noone's going to notice an extra 1kg in the bonnet and the vent looks like it will be functional even if smaller than the GRMN vent. As with many mods though budgets and use cases come into it, if someone wants a carbon bonnet without breaking the bank it's a great option, as is their Varis replica bonnet. Anyone who wants something cosmetically perfect or with more R&D will need to put up the cash.

As for rain covers Toyota need to protect themselves with their 10 year warranties. Personally i've never run rain covers and i've had some cars with wild vents before. I have the RSIC6 vents and they're huge but other than a bit more dirt in the engine back i've had no issues after 10k miles

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It'll be cheap because it's carbon cloth laid over fibreglass and in doing so it's a lot more difficult to lay the outer cosmetic layer perfectly. Making either prepreg or resin infused full carbon parts you can get much neater seams but the processes and materials are more expensive, you get what you pay for. Given the fact it's 60% of the price of competitor products you can't really hold the cosmetic stuff against it. My Scara wing was over £3k and there's even imperfections in that.

Noone's going to notice an extra 1kg in the bonnet and the vent looks like it will be functional even if smaller than the GRMN vent. As with many mods though budgets and use cases come into it, if someone wants a carbon bonnet without breaking the bank it's a great option, as is their Varis replica bonnet. Anyone who wants something cosmetically perfect or with more R&D will need to put up the cash.

As for rain covers Toyota need to protect themselves with their 10 year warranties. Personally i've never run rain covers and i've had some cars with wild vents before. I have the RSIC6 vents and they're huge but other than a bit more dirt in the engine back i've had no issues after 10k miles

View attachment 19443
mean and functional look, very nice..!
 
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Anyone have this? Thoughts if so?

I really want a carbon vented bonnet and this has a decent price, plus I think it looks better than the alternatives. Maybe even the GRMN one.

But I notice it's 8KG whereas the OEM is 6KG. Not a massively big deal but it irks me that it's heavier. I spoke to Tegiwa who say it's due to being made of CFRP, but other "proper" carbon bonnets weigh around 3-4KG. Would you prefer CFRP or proper carbon?

I'm not too sure why I'm even posting this, guess I just wanna see what you guys think.

I'd also like a matching carbon badge panel as the coloured moustache bit looks silly IMO, but I can only find the Tanso one which has split weave and wouldn't match this bonnet. Does anyone know of another that might match? Tegiwa say they could get some made if there's enough interest.

Cheers
I think the number one thing when swapping out an engine cover is to make sure it's lightweight, and then you've got to think about keeping things cool too. That's just how I see it. Oh, and by the way, I also went ahead and upgraded to a carbon fiber engine cover recently. High five!
 
It'll be cheap because it's carbon cloth laid over fibreglass and in doing so it's a lot more difficult to lay the outer cosmetic layer perfectly. Making either prepreg or resin infused full carbon parts you can get much neater seams but the processes and materials are more expensive, you get what you pay for. Given the fact it's 60% of the price of competitor products you can't really hold the cosmetic stuff against it. My Scara wing was over £3k and there's even imperfections in that.

Noone's going to notice an extra 1kg in the bonnet and the vent looks like it will be functional even if smaller than the GRMN vent. As with many mods though budgets and use cases come into it, if someone wants a carbon bonnet without breaking the bank it's a great option, as is their Varis replica bonnet. Anyone who wants something cosmetically perfect or with more R&D will need to put up the cash.

As for rain covers Toyota need to protect themselves with their 10 year warranties. Personally i've never run rain covers and i've had some cars with wild vents before. I have the RSIC6 vents and they're huge but other than a bit more dirt in the engine back i've had no issues after 10k miles

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Your Hood looks amazing, bro!
 
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This unfortunate product is a China-made replica of the bonnet offered by Japan's RS-carbon. Many of you have spent a lot of money but ended up with a counterfeit product. The original version weighs about 5 kg (vs. OE 6.1kg, counterfeit 7.4kg) highlighting the difference in Japanese manufacturing quality.
 
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This unfortunate product is a China-made replica of the bonnet offered by Japan's RS-carbon. Many of you have spent a lot of money but ended up with a counterfeit product. The original version weighs about 5 kg (vs. OE 6.1kg, counterfeit 7.4kg) highlighting the difference in Japanese manufacturing quality.
OEM-7.4kg
It is heavy because the product is a composite material of carbon and glass fiber. What's wrong with this one? The reason why RS-carbon can measure 5kg is that it is made of single carbon fiber, which is relatively light in nature. However, compared with other Japanese products, the weight of 5kg is quite high, so you can choose more products less than 4kg
 
This unfortunate product is a China-made replica of the bonnet offered by Japan's RS-carbon. Many of you have spent a lot of money but ended up with a counterfeit product. The original version weighs about 5 kg (vs. OE 6.1kg, counterfeit 7.4kg) highlighting the difference in Japanese manufacturing quality.
In addition, this cheap engine cover is not very expensive, so I do not understand what you mean by a lot of money?
You know, the dry carbon cover costs several times as much