I think I am going to race IT7R and am looking at the costs/work involved. IT7R is a new SCCA regional class that puts a Renesis engine in a 1st gen chassis.

It may be necessary to swap out to the big bearing front spindles and big bearing/spline rear axle that are not on my '83 IT7 car. What years and models should I be asking for?

My reay axle has an factory LSD with 4.88 gears. Can I use it in the big bearing rear and what to I have to change?

 

big bearing is 84-85, front and rear. the lsd might work if you put the big axle side gears in it. if not the gears will swap over and you can use the 84-85 diff

 

I'm at a crossroads with my '82 after finding chrome flaking in the housings. Instead of throwing money at used housings that will eventually flake away I was thinking of going the IT7R route as well. So....

Any ideas on how tough the conversion is?

The only difficult part I can see is the exhaust as the rules require keeping the stock RX8 manifold. Does anyone know if that will bolt up to the stock exhaust (my guess is no) or any specific aftermarket exhaust?

I know this whole thing is pretty new but if anyone knows where to find more info on how to perform the conversion I would appreciate it. I've searched but only found very general information.

 

can't be too bad

the exhaust will have to be custom, although racing beat sells a midpipe that has the right flange on it. so its not difficult

 

From what I can remember from my conversation with Blair.

Besides a Renesis engine you need to made or purcahse custom motor mount brackets that allow the use of the stock motor mounts in their original position. The two Renesis brackets bolt to the sides of the engine, not the front like the single unit for the 12A.

The engine bolts right up to the 1st gen transmission.

You need a Racing Beat flywheel and an automatic transmision counterweight to make the stock starter work.

The battery needs to be relocted to make room for the intake filter.

You need a Mega Squirt ECU for the FI. The stock unit has too many required inputs and interlocks to be of any use.

He has a part number for an inexpensive Mustang throttle body that works great with the Mega Squirt and someone making an adapter to bolt it to the intake.

The bracing under the hood may need to be relieved a little as the Renesis "over the top" intake is a little taller that the 12A or 13B.

He has part numbers for OEM radiator hoses that work.

The stock header we will all have to adapt to since we all have something different. Mine for instance is no where near stock (3" with an expansion chamber).

If I can think of anything else I'll post it.

 

IT7R is a great idea for our 1st gens. People doing all kinds of things to keep our old racecars alive.

What regions allow this class?

 

Watching with interest. Been thinking about selling off my IT7/ITA/STU/PTE POS-7 due to this and related issues. My mind could be changed!

 

i really looked at the Rx8 engine when i did the P port, unfortunately in 2006 the only real option for the Rx8 stuff was buying new, so the P port was much much cheaper, but since you can find the intakes used now, its cheap

 

After pulling apart my 12a and finding that one of the housings isn't in great shape I may just bite the bullet and go this route.... I think you can run STU as well right?

 

Yes you can run a stock port Renesis in STU at 2300lbs.

 

Yea, that's what I thought. At least then whether IT7R has come to my region or not, or there is little to no competition in IT7R yet, I know there is a class for me. And it's national... Mazda payout, etc....

Tom, can we get those part numbers from Blair? (sorry I don't know who he is on the forum). I already found the 13B RE for 1200-1500 sourced through my buddy's shop.

 

You want to check the induction rules in STU because some of the IT7R induction rules may not be compatible. For example in STU you are required to run the OE throttle body and intake (or a specified alternative) and it looks like they are substituting a Mustang trottle body in IT7R.

It seems like some of the IT7R rules are intended to lower the power output of the renesis and this make sense considering that they are still running the GSL brakes.

 

Gotcha, Good point. Either way I have decided to commit to the project. It's easy enough to swap out the induction parts when necessary. I'm done with the 12a, the housing problem is only going to get worse. I'll go through the rules more closely as there isn't an IT7R in SE yet (not that I know of in FL anyway) so STU is my only option.

 

NC Region IT7R Rules:

http://www.ncrscca.com/it-7r-rules

 

Thanks Tom!!

 

So I have a first gen rx7 live in ohio and travel to Nc often. Does this have the possibility of being picked up by the SCAA?

 

Any new information about this class?

 

You gonna come racing?

 

Maybe

 

Best of both worlds?

 

I had a small hand in this class development working with Blair on the prototype engine mounts and TB adapter. I wish I could have continued to help just not enough time in the day.

Really a neat idea for bringing all these IT7 and ITA cars back out from garages all over the south east. Maybe I can put one together one day

-billy

 

Any more information on it7r? Does anyone have a build thread or any more info on what it takes to make work? Is anyone racing this yet?

 

I would also be interested in this.... seems like cost would be around 4k to get sn engine/ parts and do the conversion. I have the time but money is tight. Am I off base cost wise?

 

You can buy a rear ended RX8 for about $2k. Part out a couple of the easy items (wheels/interior) and you end up making money on the swap.

 

Contact Blair Stitt. His email is at the bottom of this page.