Gotta link? I had trouble getting the search function to work in my favor

 

Not enough room for the oil lines to go around. Also, I needed a "Chevy" style radiator, the lower hose was too difficult to get to the other side, and I have no aluminum welding skills.

I didn't get pics of the FC radiator, but if I laid it down the way I wanted to, the lower hose nipple interfered (hard) with the motor mount bracket. It looks like it will (barely) fit if mounted like the stock radiator, though. It's only a hair larger than the tall FB radiator, so the main advantage is in being lighter.

I have a monster ****-extension electric fan already. 1600cfm = not enough I have it on full time and leave the ignition on with the engine off and cycle the coolant around between runs, and it's just barely enough. I wanted to lay the radiator down so I could more easily vent the hood, but that's just not possible unless I alter the motor mounting arrangement.

http://www.ohiorotaries.com/smf/inde...17915#msg17915

 

Yeah, that thing looks like it would be no fun to fit in there. The reason I recommended a dual pass rad is because the inlet/outlet would both be on the passenger side. Im not familiar with the 1gen, so I have no idea what the dementions are or what gets in the way, but I would think a 22"x19" would be pretty close to fitting. The dual pass is also much more efficient.
http://www.afabcorp.com/AFCO_Dynatec...r_dbl-pass-rad

I bookmarked your build thread. I didnt know you were a megasquirt guy. Ive been eyeballing the MS2 for a while now since most of the wiring on my street port motor are peanut brittle. Looking forward to this build!

 

22x19 is smaller.

Besides, if you're talking new radiators, that's way too much money. My racing budget is about $1000/year and if there are eight events costing me $100 a piece (incl. fuel, entrance, etc) then that leaves $200 for the car...

Did some work today:



4.9l F-150 throttle body, Porsche Boxster J-pipes.

 

the double pass is the way to go, but will set you back about 250-300. Griffin makes a double pass that measures 26x16 (#1-28221-x) inlet/outlet on the passenger side

you could have a local shop weld a 90 degree bend on yours to get it pointed in the right direction. probably cost 20 bucks


as far as cooling, you should run a 75-80% distilled water to coolant mixture( some people use nothing but distilled water with a water wetter), make sure you have no air bubbles and a good over flow resevior. the fan should have 2500+ cfm and a full shroud to the radiator. the air going to the radiator should be ducted with no gaps

 

But it's so much easier to just KEEP THE REVS BELOW 6000RPM because then the water pump actually works and the engine doesn't overheat. Cheaper, too. RPM = Ruins Peoples' Motors, donchaknow.

All the radiator in the world doesn't help if your engine is boiling over internally because the water pump has stalled flow because it's spinning too fast.

 

That all makes good since then. Building what you have an that kind of budget is admirable. Are the expensese of rallycrossing cheaper than autocross or track days? I would assume that the tires are cheaper and last longer, but im sure there is a lot more wear and tear?

 

Wear and tear isn't so bad.

New tires aren't terribly cheap (about $200 per for tires worth the trouble) but $30-50 used ones work well enough if you choose wisely. That's assuming you are in a class that permits them.

Track days are expensive, no question. The cheapest proposition out there (that I know of) is Nelson at $120 a day, and then you have to factor in fuel use and tire abuse, which given their run-till-your-brain-oozes-out scheduling, can easily destroy a set of tires in a single day. Possibly two sets of tires. Light on brakes, though.

Autocross is really, really light on cars, but it's so boring that it's not worth it.

 

have u thought about swapping in a manual shift turbo 350 or two speed glide u can pick both up cheap a glide has broad enough gears u can do like 60 or 70 in first and they r light and short . also look around at junk yards and find the smallst possible pully for your water pump and do u have one or two belts on it one will slip after about 5500 to 6000 rpm. i dont know what your top end is and how much time u spend at idle ,but if u look at hilborn injection they have mechanical injection with throttle bodys and injectors and barrel valves . u can look at there set ups and build your own maybe may be it will help

 

o and another thing becouse the engine has a fill neck on it as long as the radiator is below the fill point, u can use alum intercoolers as a rad. and lay it down a bit and mount it up in the front bumper area angling back to the engine or the othere way not real familer withe first gens. i ran two pulling two pushing 12" fans and sheet metaled a tunnel in the front end so the air had to go to the rad only

 

Gearing needs optimized for the 25mph-50mph range.

You cannot get TH350s cheaply. At least, not after you adapt them and dump $700ish into a converter that works well enough.

If I go with an automatic, it will have a V6 in front of it

 

thats what underdrive pulleys are for


a good manual 4 spd would seem to be better then an auto, you don't have to run trans cooler lines or a trans cooler

 

Believe me, I've thought all this through

I don't want to underdrive the accessories because the charging system is taxes enough as it is. Besides, that costs heaps money and none of the underdrive pulleys are steel. I am a major non-fan of aluminum pulleys because of the noise/slippage problems I see on so many customer cars.

A 4 speed would be very expensive. First you have to find one, that's maybe $700 for something in need of rebuilding. Then you have to adapt (??? no idea for cost - custom clutch disk for sure) and get a new driveshaft made ($$$). And then since any 4 speed worth using has a nice tall 1st that means having to get better rearend gears, which means changing the rear since the lowest commonly available Mazda gears are 4.78. With a 4 speed with say a 2.5 1st, I'd be looking at gearing in the low 6's range. Try driving that on the street with no overdrive!

I'll drive the P-port on the street, it's just that the housings are dodgy enough that I'd prefer to tow if I'm venturing more than a dozen or so miles from home. Rallycrosses are 150-250 miles away.

 

This makes me want to start on my PP project... No carb though, TBI.

 

IMO, TBI has all of the disadvantages of carb and of EFI. Well, all except that it's cheap to tune because ones and zeros are free.

 

That intake looks like its gonna work out nicely. Where'd you source the twin throat throttle body?

 

See above, 4.9l Ford truck.

The 5.0/5.8 trucks appear to be twin 51mm throttles, better if you're looking for big power.

And they have TPSes and other stuff built in!

 

Gotta love Ford throttle bodies when on a budget! Do you have a couple more pictures of the actualy plates and TPS? Im curious to how a filter will fit over this as its rather oblong, correct?

 

Please tell everyone in the Elantra world this too! haha. THey don't seem to understand what they are used for..... except for 30whp

Looks good Peajay. I Would probubly use thicker peice of metal for the support for durabuility. Going over bumps and torquing the engine may causing that one to bend.

 

That's actually a lot beefier than a lot of OEM setups.

Engine is assembled as of 11am today.

Short notes:

Used Belden 18ga wire (measures .092") and Right Stuff sealant for coolant seals, generic Harbor Freight O-rings for the the upper dowels and the front cover.

Front reg. shimmed with one washer, rear reg. compressed 1/8".

Apex seals all 7mm high in the middle, .003-.004 clearance to slots, corner seals snug but can pop back up, side seals have .002" clearance to corner seals, a little wide but it'll work. All hard seals the same ones Mazda installed in the engine 18 years and 120k ago.

Tension bolts torqued in four steps to 27ft-lb, front pulley to 50ft-lb, flywheel nut torqued to 120ft-lb plus 60 degrees

 

Arent those torque numbers a little low? I though the tention bolts were near 40, the front cover was 75-90ish, and the rear is 300? Im guessing the +60* was with a chisel and a smaller torque wrench? I forgot to ask. This is a GSL-SE 13b, correct? Does that mean your still using the heavy stock rotors?

 

I made an error - Mazda made the engine *28* years ago, not 18.

It's a regular ol' Series 1 RX-7 12A. Heavy 12A rotors, which IIRC means 11lb instead of 9.5lb like '83-85. I don't have the exact numbers on hand, but they're freely available. The light (20lb?) flywheel from a '81-82 has the same counterbalance and is a nice cheap upgrade if you can locate one. I never bothered with the math but gut feeling is that the 81-82 flywheel and heavy rotors gives the same rotational inertia as the light '83-85 rotors and the corresponding (heavier) '83-85 flywheel. The total '81-82 weight is down, but the rotors are orbiting as well as rotating, so that needs to be factored. Anyway, a forum member needed a rear side housing more than he needed the flywheel and vice-versa, so we made the swap.

I have always torqued to 23ft-lb, which is the spec for non turbo engines. You're allowed to go up to 27, and I had a somewhat good reason for this that I forgot. 32 is the highest I've ever heard, and IMO that's just a great way to ensure that your FC/FD side housings will crack apart the first time you get the engine extra hot.

The torque spec for the front pulley bolt is 50 ft-lb! The higher torque spec is for the larger bolt on the FD engines. Overtorquing does nothing useful.

The correct torque for the flywheel is 290-360, however I don't have a torque wrench that goes up that high. I don't think anyone makes one in 1/2", and I'm not going to buy a 3/4" torque wrench just for flywheel nuts. I work on *cars*, not tractor-trailers.

I used to just go to 250 and then burp it a bit more with an impact, but someone a while ago posted that 120 ft-lb plus 60 degrees is a good close approximation, so I do it that way. It's very easy, just torque to 120, mark a corner of the nut on the nut and the flywheel, and burp it with an impact (I love teh 2135Ti) until the next corner lines up with the mark on the flywheel.

 

Yeah, I had my numbers mixed up from the FSM. It listed the tension bolts at 31-39 N-m, not 23-29 ft-lb. The FSM does however list the front ecentric bolt at 80-98 ft-lb. I always locktite, so I doubt it would rattle loose at 50. I dont wanna sound like Im questioning ya here. I have absolutely zero experience with 12As and Im sure you have built a lot more motors than me.

What do you plan on revving this motor out too?

 

7000ish.

 

Blah blah, p-port 12A on the bench, everyone and their mother has one...


The injector bungs were made out of 1/4" tube nuts! Minor drilling required for the injectors to sit in there, then they were cut at a 45deg angle and welded on to the manifold, after I'd drilled the manifold where I wanted them to go.


The rail was originally on a 3.3l Intrepid. It was laying around and it was steel, and it was free, so I shortened it a little bit...