lwrobins

Bought an 85 gsl fb a while back.. as hobby project car. Paid $2800.
Loved the old 80s parts, no rust and 13b engine.

Found out has an early 74-75 13b with light steel rb flywheel. dellorto sidedraft , and crappy single rb exhaust..

Is it worth anything? love sa/fb but $1000 for true dual exhaust? what if need parts for the dellorto? Is the 3b a ticking time bomb due to age?

K-Nives

iTrader: (1)

Looks like a really clean car to me.
How many KM on the motor?
Does the carb NEED work and do you really NEED to change the exhaust?

ray green

iTrader: (14)

Not a tough decision, old school supreme. Keep it, you can buy the RB exhaust on the money you save buying something else.

Nicholas P.

iTrader: (1)

13b85-3mm apex seals. 13b 86+ 2mm apex seals. I see nothing wrong with the one you have if it has good compression. Worse comes to worse rebuild with coolant seals. I think im correct with the apex seals.

Jeff20B

iTrader: (13)

Agreed with Ray. Keep it. Drive it. Don't worry about it.

If the worry persists, get some Guatemalan Worry Dolls to worry about stuff for you.

Guatemalan Worry Doll Fair Trade Single Doll | eBay

Jeff20B

iTrader: (13)

And if my post just now wasn't confusing enough, and because I like old school 4 port engines, I can tell you that your engine has been running for a while and will continue to run for a while. This gives you plenty of time to save up for the long primary you talked about as well as some nitrided Y irons and a rebuild kit.

It's not like you really need these parts, but you mentioned it, and seemed plenty worried, so I figured I'd help out in an unconventional way.

Cookboy

iTrader: (10)

Damn nice setup.

lwrobins

Love old R100 rx2,3 cant afford one...FB is my second choice...don't like SA
Rotarys are cool but expensive.

lwrobins

20b, Jeff, I Have become quite familiar with your quotes and info on this forum. would you be interested in building me the perfect street motor? We live in the great Northwest, Must be 13b...
Remember Hayes?

lwrobins

How much are worry dolls? Hayes rotary...not the best...

j9fd3s

iTrader: (3)

there is something to this, i have an apex seal retaining toucan (long story), and in 20+ years of rotary ownership, have never had an apex seal failure.

Jeff20B

iTrader: (13)

Yeah, I remember Hayes. The IRS shut them down. I've torn down a few engines built by them. Most were terrible. A couple were kinda ok. But most were just slapped together with reckless abandon. I 've posted about a few of them in fact. I could go search through the forum and dig some of them up for you in a few...

Yeah, I can build you really nice street engine. I can do 74 spec like what you have (3B irons) or a Y plate engine with modern nitrided irons, ported out to 74 spec. I also have some 6 port stuff if you're interested in getting your feet wet with that. I'd offer you parts to do an RB long primary exhaust but they're spoken for. Of course I could build you a long primary too, but details like that really should be taken to private messages.

Hmm, looks like your PM privileges aren't available yet. I don't know how many posts you need to wrack up. Like 50 maybe?

Jeff20B

iTrader: (13)

I like the one on the far right with the heliotrope colored... hat.

Click to see full size.


In my 17 years of rotary ownership, I've never broken an apex either. One engine I built for a guy did break one, but that engine was worn down to a nub everywhere inside. Everything was new or nearly new when assembled, but on teardown the bearings/shaft/oil pump looked like the oil was never changed and the air filter was likely missing (or unfiltered air was getting in somewhere). Rotor housings and side plates were super worn the like of which I'd never seen before. The remaining apex seals were 5mm tall. I asked if he premixed or ran the OMP. He said both. I was like ok?? In reality turns out he drove the living bejesus out of it every chance he got. Still not sure how it could have worn out so fast though. Reminds me of peejay's dirt track driving, though I don't think this engine ever saw any dirt in track form...

By the way this engine had 74 3B irons and rotor housings identical to the OP's engine. I also have a build thread for it I could dig up in a few minutes too. It was black and red.

Jeff20B

iTrader: (13)

Here is the black and red 3B engine build thread. https://www.rx7club.com/1st-generati...ne-13b-657853/



Just one pic of the new engine I threw into the REPU after selling the 3B (hint I like the red and silver color scheme much better).

Jeff20B

iTrader: (13)

You asked about Hayes? I have two build theads of what I had to do to correct two of their mistakes.

https://www.rx7club.com/1st-generati...s-dust-658456/





And https://www.rx7club.com/1st-generati...no-way-672671/




Both were Hayes builds but we got lucky in that the second one was never fired up. I couldn't install it as it was. Had to strip off the red paint and go black and silver on this one! Notice the kinda uneven port job? Yeah, everything about this engine was uneven, but we did our best.

Jeff20B

iTrader: (13)

Ah looks like I just found another thread about another Hayes that needed correcting. It's short and to the point. Sorry no pics of this one. https://www.rx7club.com/1st-generati...-build-921975/

Sorry if this seems a little excessive. You asked about Hayes. I'm not trying to trash them, I'm just showing real world results from their builds.

lwrobins

will work on PM, engine does not smoke much upon startup but would like Y plates. I can save up for exhaust. Will my 48 dhla support a 180-200hp street motor?

Jeff20B

iTrader: (13)

I think you need to go into your control panel and choose to allow private messages.

As for Y plates, yeah they can be swapped in and ported to 74 spec. I'm sure your rotor housings are ok, but I do have a spare 3B just in case. I can also swap in a newer thrust assembly that won't disintigrate. You will also need stationary gears as the 3B version is short. Mazda went to a longer tooth design for 76 and up. At this point you might consider a set of new hardened stat gears for higher RPM and power handling capacity. Though stock 3mm apex seals shouldn't be taken higher than 8400 for any reason. You will alse need an 83 to 85 "high volume" oil pump.

As for your 48DHLA, no it won't get you to 200HP. They just aren't able to flow enough. Heck Racing Beat even recommends AGAINST this carb on a 74 engine, such as the stock 3B in the REPU. Why? Because it's too small. lol. So yeah your carb is too small for your engine as it is, I'm sorry to say.

The Dellorto as it was sold from RB back in the day was only recommended for the 76 to 78 US-spec 13B which had small 12A sized intake ports (which close at 40 degrees) and small US-spec exhaust ports.

They also recommended it for the GSL-SE 6 port engines with their smallish aux ports as well. I can quote from memory the power levels as tested by RB on the GSL-SE. The stock car with EFI made 135HP. Then it got the RB long primary exhaust and gained 21HP for a total of 156HP. Then they swapped in the Dellorto and it gained 21 more HP for a total of 177.

So you see, even an ideal dell setup could only just make 177 which I'd imagine was screaming the engine (increased wear at high RPM). There is no way it can make 200, especially on a true 74 spec engine.

But I see the pictures of your setup. Looks like someone added cruise control and the choke cable. Do they actually do anything? It would be a shame to change this setup as you'll lose functionality of these two cables.

I see you also have power steering. Unfortunatley the only option for a front mount oil cooler is the GSL-SE unit because it has the correct long oil hose and a hose holder which locates it down and away from the PS unit. Unfortunately the GSL-SE specific oil cooler has to be used because other versions have the oil line fittings in the wrong spot and will hit the radiator (already tested it). Your best option would be a 79-82 short radiator and matching oil cooler which mounts below the rad, but I don't know how much it will interfere with the PS pump. You can keep the beehive but your engine really needs a high volume 17mm oil pump because all 83-85 beehive equipt 12As had this oil pump. Your stock 3B engine only has a 15mm pump which is still better than the 76-82 engines which had a too-small 12mm pump. Those engiens tedn to suffer from low oil volume related problems like worn bearings and thrust assemblies/increased wear on everything etc. As for your 3B engine with its medium size pump, it really depends on mileage and how hard it was driven.

One option you might consider, and I don't know how well this would actually work for you as I'm still learing about it myself, is to do a blow through turbo with a stock S5 T2 unit and a boost prepped Nikki. This way it can keep the cruise control and the choke cable can still set idle speed. It will get you to your 200HP goal. You need a new exhaust anyway, so might as well spend it on 3" components. And your engine is coming out anyway so might as well prep it with boost in mind (oil return fitting, stronger clutch, stronger stat gears etc).

The Nikki might be too small for a 13B so keep that in mind.

I don't know if the dell can be boost prepped. But I do have a boost prepped weber 45 DCOE. It just needs some 36mm chokes and a tune. However I'm no expert with 2bbl carbs so you'd need to get it tuned or learn how to do it yourself. I can provide all the jets and air correctors the PO bought. You can order a carb hat or have one made. Just a note this carb was used on a streetported R5 13B and it made like 200HP we think (it was never dynoed but man it was quick).

Your car will need a Moog idler arm as the stock version hits the S5 turbo or is like super close. You will also need an MSD fuel pump and a Mallory pressure regulator.

This is just an introduction. It's kind of an involved swap and you'll need to do a lot of research. There's no way I could cover everything in a single post. And the cool part is it doesn't have to be done any time soon thus allowing the engine to be redone first and broken in NA before you ever even consider boosting it.

j9fd3s

iTrader: (3)

there is about a 99.5% chance that the engine was rebuilt at some point. and B, the 1st gen Rx7 is about the easiest car to keep running on the planet

Jeff20B

iTrader: (13)

What do you say or ask? Something like, "Please keep these apex seals intact," and just go with it?

j9fd3s

iTrader: (3)

well a very long time ago, my friend crashed his BMW, and then his Rx7, both times on wet pavement. so he bought a traction control penguin, and we all thought he was nuts, but no more accidents.

so we were at disneyland for sevenstock 4, and i bought my apex seal retaining toucan, and installed it in my room and have never had any sort of trouble with apex seals.

so it was as simple as buying said toucan, declaring the function, and keeping it somewhere safe.

i may have been better off with picking a dollar bill attracting gazelle, but you live and you learn. or don't learn, or whatever

ray green

iTrader: (14)

"the 1st gen Rx7 is about the easiest car to keep running on the planet"

A greater truth has never been spoken.

But just in case, J9, where can I get one of those toucans?

Cookboy

iTrader: (10)

^+1

j9fd3s

iTrader: (3)

i got mine at disneyland

might be wiser to be slightly less specific, perhaps you could find a "generally healthy engine" rhino or something

Jeff20B

iTrader: (13)

This actually like a form of magic, and it works. We're just never taught this in our society in church or school.

I think I'm going to get worry dolls for my family members. They worry about stuff a lot.