I'm new to the forum, but have learned a ton in the last week or so. Thanks!! I just bought 2 (RX7 verts... one I intended to do a turbo swap and a few days later one where the swap was almost complete). Anyway...
1- I don't see much discussion on weight saving in the RX7. What net weight should I aim for in a 'vert. What light-weight components are viable? (Hood, fenders, smaller battery, etc.) What can be made to be easily removed and replaced? (Top, top motors, etc?) I love the stock BBS's, but what are the choices in lighter wheels?
2- What acceleration might I expect from 'vert w/205 RWHP? I know, there's probably a calculator ou there for that.

 

Depends on how comfortable you want either of these to be. There are numerous ways to save weight.

 

Which begs the question; "and those ways are...?"

 

Well there some sound deadening insulation in the floor boards that can be taken out. That can take off about 20 pounds. Also you have the basic stuff like your spare tire, jack ect. The seats in the verts are also very heavy, so you might consider replacing those. Most of the other things you had mentioned are already very light and really dont need to be replaced. The vert bbs wheels are around 11 pounds each i believe, which is very light. The hood on the verts should be aluminum and are also very light. Another swap you could consider is a lightweight flywheel, driveshaft and possibly throwing in a 4.3 rearend from a GTU. Aside from that I'd do some emissions removal and make sure you have a good fuel setup, intake system and exhaust on the car. This should give you some pretty decent power

 

verts are a couple hundred pounds heavier than coupes ( i believe my friend weighed his stock vert at about 3100 lbs.). first gut the interior and take off the top, start gutting the engine bay: p/s, a/c, and if its a t2 motor, the air pump. also replace brackets and such with zip ties and such. and if you dont mind the look, sleek headlights save quite a bit of weight since you do not need the electric motors for the pop ups.

 

The biggest weight savings is from a stock exhaust to any aftermarket system with no emmison controlls.

 

The coupes weigh about 2500 pounds. I dont think the verts are 3100 lbs heavy.

 

coupes are around 2800

 

S5 verts can be that heavy. 3050+ is not unusual for a S5 vert.

and most S4 non turbo coupes were in the 2600-2700 range, none of them were 2500 without major weight reduction.

Stock S5 coupes were 2800+ with Turbo coupes adding about 150lbs to each series.

Stock S4 verts were just under 2900 for non P-package manual tranny verts and just over 3000 for P package verts.

But back to the originators question, the verts all came with lightweight parts like alum hoods, alum jacks and spares, uberlichet 11 lbs BBS wheels etc.

The only weight savings you are gonna get on a vert is by stripping.

 

This is good info and is making think that I should keep both RX7's. The '89 NA for comfort and strip-out the '88. Maybe even go with the 50's brit-car look and use a half-height windshield and dump the passenger seat. If I paint both cars the same color and only park one at the house, my GF will never expect.
Seriously, we don't mind a bit of road noise so the insulation can go and I already have Corbeau seats on order. I will see what else I can rip out... er... remove.
What's the advantage in 1/4 mi times of a 4.3 rear? I'm gonna guess the stock is about 4.1? The guys at RP Performance in Chantilly, Virginia are looking around for a rear-end now, I better communicate this to them.

 

You may wish to read the What did my Car come with standard features and options sticky thread at the top of this section... it lists things like rear end gearing.

But your 88 would come with a 3.9 year end (regardless of tranny) for gearing, only the S5 convertibles came with a 4.1 (regardless of tranny).

In coupes the 3.9 rear end was only found on automatic tranny cars, with manual tranny (except for the GTUs model- note the small "S") came with a 4.1 rear end. The only the 89 and 90 GTUs model came with a 4.3 rear end.