Is there any input you guys can give on wether it its better to buy a clip or motorset?

My Honors engineering class this semester requires an indepenent project, an I thought about trying to make a "How to, 20B into a RX7 conversion" Basically there are not really any guidelines to follow only that it has to work in realife, to make it cost effective and have drawings to prove it. I was hoping you guys might give me a few clues as to problems that are incountered during the swap.

I have been trying to do alot of research over the past couple of days and i have only really come up with:

Steering rack
transmission moving back
extra weight added
egine mounts

Anything else? LMK PM or reply here. I will keep you all informed with my progress!

Thanks!

 

what model are you gonna put it in?

 

Well, i guess i left out the important part, FD.

 

A question for the honors engineering student who is totally missing the boat IMO...

Grasshopper, what is the first step in the problem solving process?

 

When you can ****** the pebble from my hand.....

 

Evil Aviator, I do not understand what you are asking? If you want the steps here ya go!

1. Understand/Define the Problem
3. Gather info (Brainstorm)
2. Make solutions to the problem
3. test the solutions(obvisiously thats going be a little hard) -understand/define new problems
4. Retry until prblem is sloved

 

look at your wallet!

mike

 

I am not doing the swap, i am only coming up with all the problems and solutions for them. But i need to state all costs. I don't care if it costs $100k to do the swap, its just a project for my class, i do not have to complete it. Thats why i am asking people in the forum here.

And when i mean "cost effective" all the time, money weight must be insignificant compared to the gains.

 

A front clip is really no advantage over a motorset that includes the coils and igniters. Most of the rest of the clip is useless for a FC/FD project.

Gary
20B S4 RX7 drag car
20B JCESE Cosmo

 

Fianlly some good input! Thanks!

So motor set it is.

 

Very good, Grasshopper, you have proven yourself worthy of your degree major. Well, your numbering system is rather unique, but we will look past that, hehehe.

Now, look at what you posted. Are you identifying problems, or are you identifying fixes without addressing the problems?

For example, one problem is that the 20B does not physically fit in the stock engine bay. You do not necessarily need to move the transmission back, or modify the steering rack, but these are options for solving the fitting problem. Does that make sense now?

Also, depending on what you remove from the car, the total static weight may not be an issue. Pettit's 20B Banzai is actually a little lighter than a stock FD. Your "problem" here would be the static weight distribution, which can be solved by moving some components, such as the battery. Another weight "problem" would be the polar moment of inertia, which I don't believe has been addressed by any of the 20B conversions that I am aware of.

Hopefully you understand my point now. You may also now see why there isn't just one bolt-on kit for the 20B conversion, as there are many different ways to skin this cat. Also, if you consider synergism (which you should), a given solution to one of the problems may affect other problems.

LOL, that's definitely one of the problems that needs addressing.

 

i had a very good example if that the other day. tuning the twin su's on my tr3. imagine 2 different ecu's to run your engine, and since they share a common plenum, any change you make to one affects all. add in a sticking dashpot and you can have too rich and too lean at the same time.

mike

 

Most of the engines available from the various importers do not include the coils and igniters. This does bring up another interesting point, in that a lot of the 20B conversion depends on what you start with.

Geez, can't you get a divided plenum? That sounds like a nightmare.

I was going to direct you to the Pettit Banzai article, but it appears as though it is no longer available on the Pettit website. Somehow the article seems to have appeared on this other web site, but I have no idea how it got there.
http://www.geocities.com/evilaviator/

Also see this site which covers some of the issues of an FC conversion, which is very similar to an FD conversion.
http://www.se-rx7.com/20b/

 

From what guys have posted on here about fitting the 20B into an FD, and my own experience with the same on an FC, I would have to say the FC seems much easier. No PPF to get around for a start, and the 20B sits in the FC bay almost like it was meant to except for the height of that damn intake manifold!
Gary

 

its got the stock setup, it turns out there is a way to do it that doesnt get you lost. plus you have to unstick the dashpot!

mike