2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

Marren 750's and 1000's install writeup... not TOO hard...

Thread Tools
 
Search this Thread
 
Old Jun 23, 2005 | 09:57 AM
  #1  
YearsOfDecay's Avatar
Thread Starter
Locust of the apocalypse
Tenured Member 05 Years
 
Joined: Apr 2003
Posts: 2,553
Likes: 2
From: Directly above the center of the earth (York, PA)
Marren 750's and 1000's install writeup... not TOO hard...

I installed some marren 750 primaries and 1000 secondaries in my TII yesterday..

THe Marren 750's (low imp., japanese style) are very CLOSE to the stock injectos, but are a bit fatter.. and there's the rub...

The area machined out of the center Iron for the injectors is to narrow to fit the marren injectors.. they LOOk like they are going to make it until you tighten the fuel rail down.. then they hit at about the 11-3 oclock area if you are leaning over the passenger fender looking at the iron.

SOLUTION: DIE GRINDER... first.. Pull the little showerehead lookin things out of the holes, this required the making of a special tool out of a pair of needle nose plies by bending the points outward into sort of hooks, then inserting the pliers into the hole and, while holding the pliers open, pulling out the iunserts.

Then.. to avoid getting metal into the injector holes, I stuffed about 1/4 of a plastic bag (walmart type) down into the holes, leaving a little tail sticking out to remove it later. I made sure that the bag was compacted BELOW the area where i was going to remove metal so that it souldn't get caught on the die grinder.

Next, i ground out the area that was contacting the injectors (the raised part in the center and to the top, i DID NOT mess with the area that is flat to the rest of the iron... this would compromise the injector seat) .. I removed about 1/4 inch of metal in a 45 degree angle around each injector hole. After I removed the metal.. I turned on the sho-vac and put it over the holes as i pulled the bag-plug out.. worked like a champ, no metal got down in the holes.

Now, since i removed the little spray deflectors, i had to come up with a solution to the hole depth left from removing them.. Well, when i removed the deflectors the bottoms broke off off so that I was left with just the jetson house looking top. onse side flat, the other with a beveld tip sticking out (where the two skinny legs that held the deflector were attached). I cut the first ring off the top and dremeled it flat to the next ring. now you have two rings, one flat and one that has the beveled end sticking out the center.

I inserted this into the hole with the beveled end down. Then I Inserted TWO of the grommets from bottoms of the stock injectors on top of that... Now, i had the proper depth in the hole (about 5-8mm) so that the Marren bottom Injector grommet would seat properly and the injector would be held firmly, but not too damn tight when you clamped the fuel rail down.

The marren injectors do not need the top grommet used on the stock injectors as there is a machined ring on the top of the injector that will seat against the fuel rail, and there are two O-rings that fit inside the fuel rail so they wont leak. by using two stock injector bottom grommets in the hole, i built up enough of a spacer and also gave some elasticity to the mounting system so that when the fuel rail is clamped down, the injector is compressed, but not smashed, into the hole, thus creating a good seal.

The 1000's were REAL easy.. I have a K2rd secondary rail for 1600's, therefore i ordered AMERICAN style 1000's that have the thicker input tup and use a huge o-ring. BUT, unlike the 1600's, the Marren 1000's can use the STOCK bottom grommet. You just take the marren grommet off, use a dremel and grind away the lip for the grommet, then slid the stock bottom grommet up over the neck on the marren injector and plop it in. Now, i've removed the diffuseres from the LIM as well, so, i inserted a old bottom injector grommet in the hole as a spacer, but, if you left the sprayers in there, you shouldn't need to remove them.

Those Marren 750's ROCK... the car idles SOOOOo smooth. I haven't tuned for boost yet, but the throttle response and idle under vac with just the primaries running is freaking AWESOME!!

Well woth the two hours it took to modify and install them!!!!

Last edited by YearsOfDecay; Jun 23, 2005 at 10:01 AM.
Reply
Old Jun 23, 2005 | 01:22 PM
  #2  
Rx7Ridah's Avatar
Senior Member
Tenured Member 15 Years
iTrader: (8)
 
Joined: Nov 2003
Posts: 533
Likes: 0
From: Green Bay
any pics of before, during or after?
Reply
Old Jun 23, 2005 | 02:30 PM
  #3  
Bukwild's Avatar
Rotary Freak
Tenured Member 15 Years
 
Joined: Apr 2003
Posts: 2,702
Likes: 1
From: DC Area
yeah I noticed that the idle was rock solid with my new 720's in the primary slots with the haltech. 100 times better than my stock 550's and the stock computer
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Snook
3rd Generation Specific (1993-2002)
14
Oct 1, 2015 10:56 AM
apooch
Single Turbo RX-7's
8
Sep 4, 2015 10:27 AM
tiger18
3rd Generation Specific (1993-2002)
9
Sep 3, 2015 08:27 PM




All times are GMT -5. The time now is 01:15 AM.