kmonto85

As my other thread was about my engine going Kaboom and the definitive outcome and have searched and read many websites. What I find interesting is that there is a pretty good chunk of links in this thread below that these are dead and I can't really find much via google or yahoo searches if they moved on or what not. However, some do still exist and I have researched them.

https://www.rx7club.com/showthread.p...erformance+13B

What I am interested in seeing is the dyno numbers from these still around engine builders? The prices seem to be in the range of 1.5K all the way to 4K for relatively similiar features and plus more for mods. The prices vary but with similiar configurations on provided details of what is done to the motor. However, I do not see any dyno numbers. Some say 5-10% for stage 1 street porting and some say 10-20% for stage 2, and that even varies then this and that but no real numbers.

I guess for spending 1.5K to 4K on a reman ( some are only overhauled and replacing only the bad parts ), I guess I was expecting a bit more. Maybe I am just going through information overload. Hell, even the warranties varies and the fine print seem to be all different.

Some say they had good luck with this person and some say try this person... Then their are the horrible posts of people being taken advantage of.

Man, I guess I just need some warm and fuzzy... I truly want to stay with the 13B engine, but I want it modified for more power NA only.

Any additional intel anyone can shed to help me with this?

teddyrx2

iTrader: (33)

what kind of motor setup do you want to do...We know you want more powere...but whats your range of hp whats your range of money to spend...whats your whole game plan?

kmonto85

I want to spend <3K for a replacement engine for my broken one.

For 3K I wanted to be able to pick and choose my vendor based on quality, and what they delivered for that price.

Since the stock engine was suppose to generate:
Engine specs:

1979 198? +
12A 12A 13B
Displacement: 1146 cc/70 cu in 1146 cc/70 cu in 1308 cc/80 cu in
Compression: 9.4:1 9.4:1 9.4:1
Horsepower: 100 @ 6,000 101 @ 6,000 135 @ 6,000
Torque: 105 @ 4,000 107 @ 4,000 133 @ 2,750
Induction: Nikki 4 bbl carb Nikki 4 bbl carb Bosch L Jetronic FI


I was hoping I could get 175hp/175tq for $3K. However, if you take the stage 2 max increase projection by one of the vendors, that means 162hp. However, I am not seeing any dyno numbers that proves that. I guess I am just trying to justify spending $3K on something that is somewhat a mystery to taken it apart myself, get the DVDs, and do it myself for less apparently.

It's kind of like making a business decision, I just want to weight all aspects before I drop down the money.

Now I do know intake and exhaust play a heavy role in hp and tq making. But with the stock intake and an opened exhaust, shouldn't this be possible?

Maybe I am just asking to much....

Clearkut

iTrader: (1)

any porting that will get you those desired # will require a nice upgraded intake(properly tuned to new engine)/exhaust setup, ignition, probably want to do the clutch while your in there as well, besides that, a large street port will get should get you close, if losing a bit of drivability isnt an issue check out what a 1/2 bridge or bridge will do for you should be able to beat 175 no problem, with proper addons/tunning

orion84gsl

iTrader: (5)

I would recommend going to your local pick-a-part and find an FB/FC chassis with fairly low miles, just wrecked, and yank that motor. It will save you some money. Get the DVD and crack it open and port and rebuild it yourself. You could use your popped motor for practice and then when your comfortable with your technique, move on to the new engine. All in all you would probably save alot of money that can then be used for upgrades.
Good luck

Aviator 902S

Where many guys (and alarmingly, some rebuild shops) run into trouble is by trying to re-use parts that shouldn't be re-used. All the street porting and exhaust/ intake work on the planet won't help you if those rotor housings with "just a little minor flaking" are not replaced with new ones. Once the flaking has started it never gets better, will last as little as 10,000 miles after the rebuild (unless you get very lucky), and without warning scads of chrome disappear out the exhaust. When this happens the symptoms are the same as a tossed apex seal. Ask me how I know.

Ditto for re-using irons that have worn beyond allowable specs. By this time most of the factory nitriding (hardening) has disappeared and the wear marks will rapidly wear out those new side seals you've just installed. Even re-surfaced and then re-nitrided irons don't last as long as factory originals.

And lets not forget about other items like thrust bearings, rotors (especially the grooves in which the apex seals reside--- if they're worn those new apex seals you install will be treated to an early trip through the exhaust ports, taking those nice shiny rotor housings out of commission en route) and the pilot bearing and frost plugs.

A decent rebuild shop will replace everything that should be replaced with new parts, but the cost for these parts are prohibitive: rotor housings that sell for upwards of $500 each, rotors at $400 and irons at around $400 each. Now add the cost of a new *complete* rebuild kit and you'll quickly find yourself at over $4000 in parts alone.

Mazdatrix in California will gladly sell you a re-manufactured engine with all of these parts replaced with new---- for around 6K. They also sell lesser rebuilds for lots less, but you get what you pay for.

I'd just buy all the parts separately from someone who can order them straight from Japan at a discount, and then do the rebuild and install myself. The 12A that's in pieces on my work bench has good irons, rotors and e-shaft, but the rotor housings, bearings, all seals and rebuild kit will cost me around $1800.

One more thing:

Don't be too quick to blame the rebuild shops if one of their rebuilds doesn't last as long as it should. Often, it's the customer who is trying to cut corners by telling the shop to re-use parts that should be replaced, citing being too broke (a common ailment among buyers of cars under 5K) to afford a proper rebuild as the reason.

Often, these customers then sell the car, telling the new owner that the engine has been rebuilt and that such and such shop did the work--- while failing to tell the new owner that the work was done to the customer's satisfaction rather than the shop' owner's. Guess whose reputation takes the hit when this engine only lasts 25,000 miles? Hint: Not the previous owner's...