I am planning to maybe go 20B but I need to know if my v-mount would work or what I need to do to make it fit.

If you can measure the space in between the front of the motor, let say from the pulley to the hood latch.

Thanks in advance

Kai

 

Hey Gordon, either way can you still measure it, it should be about the same... ...thanks

I just need a general idea on how close it is to the front frame..I have pondered the thought of going N/A so that is still not out of the question...just trying to gather more information on going 20B to make my final decision.

Kai

 

I can *almost* guarantee that it won't fit without some considerable fabrication/modification. For a rough (but really quite accurate) idea, add the thickness of a rotor housing to the front of your engine and add 70mm to that.

 

if you are good at fabrication anything will work,,but measure and check for options we have a greddy front mount with custom built pipes by me for the ac to still mount and work good...

 

That would be great, thank you Gordon...Kai

 

Gordon,
That will only work if Kai is going to make a custom sub-frame like Chris'..... Otherwise the engine will be considerably closer to the front of the car (hood latch). 95% of the other 20B sub-frame "kits" out there will place the engine in a totally different place than the beautifully designed one that Chris made.


Also Kai, this doesnt just go for Chris', there are a ton of different sub-frames out there that place the engine in a different location.

Just something to consider.

-J

 

What would be the best subframe kit out there that does not screw up the bump steer?

 

I've owned that subframe and that subframe itself moves the rack (just like all the other subframes that sit the engine in the stock location). You have to also buy the correction kit or modify the spindles to help bring the steering geometry back to near normal. It's still not perfect though.

 

so does the rxspecialties need a bumpsteer kit or not..kinda confused..I have broke it down to the rx7 specialties or the one of Logan "gtorx7".

 

Yes, it does need a bumpsteer correction kit. I have the same subframe but bought it from Pettit. To correct bumpsteer on my car, Pettit modified the spindles on the car. Although this works, I'm not sure I would go this route again. Don't like the thought of having someone hack up the spindles and rewelding them to reset the geometry. Anyway, you don't have to do this anymore as the correction kit is available. I have pics of my spindles versus stock ones but can't seem to find them right now. I've seen the new bumpsteer correction kit as Alex at Gotham has it for his 20B and they look really nice.

I think the Defined Autoworks kit doesn't require the correction kit. The disadvantage to my knowledge of this route is you can't you PS or AC with the latter being very important to me in FL. With the rxspecialites kit, you can run both PS and AC.

 

EVERY subframe on the market requires bumpsteer correction. The ONLY "off the shelf" product that keeps your subframe stock (and thus has NO bumpsteer correction needed) is Logan's kit.

That aside, as has been mentioned, custom fab makes anything possible.

 

I run the RX7 specialities sub frame and it has a bump steer kit. Kai I will measure the space tonight, but to fit a v mount is a serious project. I would go with a front mount. The only clean vmount fit I have ever seen is RE-Amemiyas son's, and obviously they did the fab work and cut the firewall to move the engine back. It does look unreal though.

http://images.turbomagazine.com/feat...ngine_view.jpg

 

Great info guys...thanks a lot...I am leaning towards the rx7 specialties subframe it seems to be the better route, I like gtorx7's kit but I just can't seem to get over the fact that you would need to cut and shorten the LIM.

Keep the info going...I have a lot to learn as I am planning to do this myself.

 

My #1 intent for my 20b fd project revolves around the idea of building a car that I felt Mazda should have built. So I'm taking an engineering approach as if I actually worked for Mazda R&D and was given the opportunity to install a 20b into an fd myself. That means putting an engine over a rack and moving more weight higher and past the center point of the two front tires is an absolute NO NO. It's always been Mazda's design intention to move as much weight lower and as close to the center of the car to improve the vehicles center of gravity and polar moment. The laws of physics doesn't lie when it comes to weight distribution and placement. This is the main reason Rx7's handle the way they do. I don't want to compromise this since I'm installing a heavier and longer engine. That's why I decided to ditch the Rx7 Specialties rack and fab my own.

Moving more weight towards the center of rotation and lowering the center of gravity improves turn-in, makes the vehicle respond quicker to steering inputs, and overall improves handling feel. With where my engine currently sits now, my engine is exactly 2" lower than the stock rew engine and sits directly behind the rack. Now given the 20b's extra length, obviously my transmission is moved back as well. The nice thing about that is more weight towards the center of the car. My rack is untouched. I did no cutting of the firewall or anything like that because I'm building a custom intake. The stock LIM is why you have to hack the firewall when moving a 20b engine back.

Now I don't expect to see a huge difference in feel when compared to the stock set-up, but I do know for a fact that when it's done, I will have a better foundation to work with. We all have our project goals. Some do these swaps for just more reliable power while others do it for rarity reasons. Mine is to 1st stay true to Mazda's engineering design philosophy. Power!!!!! I can always make that later. Hell's it's a 20b

 

Yea I definitely know how expensive it is to go the route I'm going so I completely understand your direction. I don't have the kind of money to pay someone to do what I want so I'm fortunate enough to posses the skills to do it myself. As 4 my transmission, I moved my shifter forward to the access plate. The shifter is exactly where it once was. Planning took a while but when I figured it out, the execution of the plan only took like 30mins to do it. I really can't wait till I'm done as I spend soo much time planning my moves and actually really not doing much work.

 

Our kit comes default with keeping the p.s intact. We are making a version that keeps a/c and deletes p.s. If going N/a we CAN keep a/c and p.s. It uses the full factory subframe, thus no danger of any bad welds (not saying anyone makes faulty subframes, but human is human) No bump steer corrections, and factory everything. We modify the stock intake to fit, its easy, and it works great. The factory 20b pan is used, as is the 20b rear iron. Keeps the FD waterpump. My personal 3-rotor even with a drysump still uses our 20b conversion kit. Drysump or not, my kit places the engine as low as you can go with stock steering rack placement. It seems like a easy decision to me, modified intake manifold vs bump steer correction, non factory subframe.

KaiFD3s we just finished up a 20b turbo with our kit, and it has a v-mount too. The setup is much different than anything else I've seen, but the center of gravity is very very nice. Hood latch could not be retained, other than that the chassis/tranny setup is full factory. In a couple weeks you will see some pics of it.

 

Hey, Logan I will wait for the pics of this beast you built, I'm not worried about the hood latch as I took mine off, I am using the aerocatch as a hood lock now..
Guess I may still go with your kit...

 

thats how my stuff works out too, but if you do your homework, it makes huge tasks like a 3 rotor managable.

 

Hi Gordon,

My experience with the rxspecialties (Pettit in my case) subframe and bump steer is very positive. To reiterate, the rxpsecialties kit DOES require a bump steer correction kit as the steering rack is repositioned. Logan's kit DOES NOT require a bump steer kit but you lose AC capabilities which for me, being in FL, eliminates the kit as an option.

As for having bump steer problems with the rxspecialties subframe and with the correction kit installed, you won't have any issues. I've driven my car enough to report very positive results. The car does not wander and steering is precise. And this is with my very wide (12.5 inch) Forgelines on the rear of the car.