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View Full Version : Couple of questions......



Boswoj
02-14-2002, 05:37 AM
Hey guys - I've got a ITA/Pro-7 car that I'm cleaning up for the upcoming season, maybe you can help:

1) Anyone running a Kirkey seat? Which one, roadrace or intermediate? I'm about 6'1" but with short legs and long body - having headroom problems with current no-name seat. Is 20 degree Kirkey the solution?

2) Are there any cheap options for a compression tester? Hate having to load up car and run it to someone when I want to do compression tests!!

Thanks in advance!
Rick

02-14-2002, 01:28 PM
for compression see, Topic: Buying a Junkyard 12A? found below this one.
on the seat do like i did, cut the stock seat mounts off the floor and mount that puppy 1" off the floorboard, gave me 4" from helmet to cage, I have the Cobra imola 2 $460.00 ouch.

Daryl
ITA RX7 #90
SFR



[This message has been edited by 7'sRracing (edited February 14, 2002).]

ddewhurst
02-14-2002, 03:14 PM
Rick, this would be what Daryl is refering to I would think. See below.

Daryl, did you find time to try & see if this works ? Ya realy had the H board going for a couple days. It was fun to have some Mazda posts on the British board. http://Forums.ImprovedTouring.com/it/tongue.gif

To the curious RX-7's folks with reference to compression testing a 7. The following is what I have read but never tried.
The Mazda compression tester is in the neighborhood of $1,200.00. Don't matter if it's $500.00 that is to rich for my blood.

So lets get to the Poooo boy method.

Per what Bill Emery passed on pull a plug & listen to see if the three sounds per rotor revolution are the same. Listen for an odd mechanical noise. If one seal was going or gone the sound would be different. Also if a finger was rested at the plug hole maybe you could feel the difference in air velocity if a low compression came past. ???

On to the improved poooo boy method.

Warm the engine up to normal operating temp.

Use a normal compression tester with the release valve removed or held open.

Watch the compression tester as the engine is turned over & view the compression numbers. Three numbers per rotor revolution, one for each combustion space. Having never tried this test & while typing this info it comes to mind that these compression numbers are going to peak & dissapear in a hurry. O well you never know untill you try.

Again from info that I have read normal compression numbers with the bucks up Mazda tester are 85 to 110 psi. When using the poooo boy method expect compression numbers of 20% less. 70 to 90 psi. Compression below 80/70 psi is no good.

Please do not shoot the messanger. If anyone has or does try the poooo boy method how about posting the results.

------------------
Have Fun

David Dewhurst
CenDiv Milwaukee Region Spec-7 #14

RX767
02-14-2002, 04:26 PM
In response to:" Anyone running a Kirkey seat? Which one, roadrace or intermediate? I'm about 6'1" but with short legs and long body - having headroom problems with current no-name seat. Is 20 degree Kirkey the solution?"

- When I bought my '81 ITA RX7, it came with a cheap seat that was ok for autocross but nothing I want to use in a hillclimb or road race. I use the Kirkey Intermediate(resonably priced through "Racer Wholesale") and I am 6'3". I used steel 90 deg. angle brackets that I mounted directly to the floor and backed with large washers. I drilled through the sides of the seat and bolted the seat to the brackets. I used "I/O Port Racing Supplies" back brace that mounted easily to the seat and the cage. This set-up has me three to four inches under the rear hoop of the cage.
All the best,
Bill Emery

02-14-2002, 05:35 PM
David, can you believe there would be so many opinions on a 1/8" hole in a roll cage? then a comp board post, on a friggin 1/8" hole?.
would you believe im still messing with wiring, we really need to update the friggin rules on wiring, disable anything and the thing wont run, but thats a whole nuther thread.
I did get the heater box back in but theres a bar in the way to put the blower back in for my defroster so i ran a duct from the pass window down to the heater core so the defroster will work when i need it, at laguna in the rain!
i hate working under the dash.
should run this weekend then ill try the compression test.

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Daryl Brightwell
ITA Mazda #90
SFR, NORPAC



[This message has been edited by 7'sRracing (edited February 14, 2002).]