I need some help with replacement hoods for my 93 R1. I is fully modded for track use and I have an overheating problem at the track despite upgraded fluidyne radiator. My plans now are to duct the radiator, run more water in the coolant and drill the thermostat.

I was also going to replace the hood with a carbon fiber vented hood. Please everyone submit opinions as to which is the best choice for cooling. I have a M2 med intercooler so it has to clear that as well.

Thanks
Raj

 

you need a front bumper not a hood. i'd recommend the mazda gtc front bumper. the hood won't help much unless your sitting still.

 

I'm gonna have to second Fritz's idea. Skip the hood and get a front bumper. And i'm gonna have to agree with Fritz again. The mazdaspeed GTC bumper is an all around great front bumper. It has a big intercooler opening, and big oil cooler ducts. And on top of that, it looks killer.

If choosing a hood for cooling, i'd prolly have to go with the Scoot hood. It has two big cooling ports, and it also has an air inlet port which directs air to the abs/turbos and toward the brake master cylinder. But i believe this is only on the original and rotary extreme version, but it was removed on the VIS replica, but i'm not sure. If someone does know, please correct me.

 

Maybe you could put some kind of washers on the bolts for the hood by the wind sheild. This might help some of the hot air exit the engine. There also might be a rubber seal that you might be able to removeat the back of th hood. I beleive I've seen this done for cooling on many japanese cars. This also would help save some money for the front bumper. But I would recomend hood pins if you decde to go this route

 

Thanks for the input guys. Where do I get one of these??

Raj

 

Removing the weather stripping on the stock hood doesn't do anything at all. Search through on the 3rd gen forum and you'll see some threads where a couple of people tested this with no difference in temps.

On your heat problems do you have SMIC or FMIC? I've heard bad news (sadly) about heat on track regardless of radiator with FMIC. If you do have a FMIC you may want to look at a larger SMIC instead.

 

I'll take it from that quote that he has a stock mount intercooler.

The scoot hood will clear the intercooler, and the cooling ports are behind the intercooler, letting more hot air out. Performance wise, this is probably the best hood to get.

Look wise, i like the mazdaspeed hood, but looks dont matter as much as performance on the track. The main problem with the mazdaspeed hood is that the hood vents would be right above your intercooler. For maximum cooling efficiency, it is best to have the vents after the intercooler.

Damian did a poll on finding a hood. The thread has a lot of usefull information. Check it out.

https://www.rx7club.com/showthread.p...hreadid=315421

 

from what I have gathered in the 2nd gen forum

that would be okay if the car is trailered to the track but for anything driven on the street that is no good. In a front end collision the hood is not blocked on the rear end so rather than folding like it was designed to do it gets pushed right back in through the windsheild. One of the most dangerous 'mods' you can do as icemark put it in the 2nd gen forum.

I also read that there is no cooling benefit from raising the back of the hood.

 

Knight Sport

 

Scoot

Good Ventalation

 

Out of curiousity, in the future my car will be doing dual street/track duty and I like the look of the 99 specification front end. Does the 99 front end offer better cooling than the stock front end?

 

Section 8. Yes it does. There's also the sharkmouth mod to the stock front that allows for more air as well. I'll post when I find a pic, but 99spec=better.

As far as raising the back end of the hood, this actually sucks air in, causing increaded pressure under the hood. Also, you don't think accidents happen on the track too? You finna get split

 

 

Not sure why, but everytime I try and link the pic so it shows up in the thread, the forum just links it. Strange.
Click the link.

 

If you have a radiator and you have not properly ducted it yet that is the single largest improvement you can make along with running 90% water / 10% coolant.

I agree with the others: A vented hood ain't going to do squat for coolant temps. Unless you build an exit duct from the radiator to the hood vents (good luck) you really don't gain anything.

 

Yeah, I've heard of that, but I haven't gotten around to searching on what's involved in doing it. A friend of mine has done something similar as well. I'll probably do that until I'm ready to pony up for the 99 front end and a new paint job.

 

https://www.rx7club.com/showthread.p...ht=shark+mouth

There's the thread I got this from.