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Login to post Forums » Grassroots Motorsports » Progress on the Jensen Healey project 56k uh uh!

May 28, 2009 6:37 p.m. Jensenman SuperDork

The Jensen Healey I got last October has undergone a few changes, to put it mildly. Here's the front suspension with Miata knuckles and QA1 shocks: Here's the Mazda RX2 rear axle which has a 1st gen RX7 limited slip and 4:86 gearing, mounted on my own design 3 link suspension: Reckon this will be enough tire? 13x10's with 22x10x13 Hoosiers. Here's one of the rear QA1 shocks in place:

I figured I'd better reinforce the upper shock mounts: The suspension is completed, I have the throttle and clutch cable linkage fabricated, tested and installed. I modified the pedal box to accept an RX7 master cylinder. Now it's time to start test fitting the engine. Lots of room in there.

The engine needs to come back ~3/4", up about the same amount and be leveled out but this is basically where it's going to reside. The shifter is within 1 1/2" of the stock J-H location. Next: building the engine mounts and fabricating a set of headers. Then wiring, fuel pump/cell/ lines, fabricating a radiator and oil cooler mount, fabbing an aluminum dash... wow. Plans are to light it off sometime in August. No, this is not a Challenge car!
May 28, 2009 7:44 p.m. tuna55 New Reader

You clearly need more tire. Are the rears going to be that wide too? Nice rear shock tower brace, are you sure it's big enough? hardy har har. I can't tell much about the rear suspension from the pics, but straight axle stuff is easy to get right.

I can't wait to see it run. Nice work.

just one thing though, 10" wide tires and non vented discs?

-Brian
May 28, 2009 7:58 p.m. thatsnowinnebago HalfDork

I bet a 20B would fit in there...
May 28, 2009 8:03 p.m. alfadriver HalfDork

Not bad for a salesman

Seriously, though, are you going to fabricate the wiring yourself, or buy a "kit"? I'm just about finished with the one for my race car- they are not too bad to build, and I used some really cool mini breakers.

Pretty sweet work.

Eric
May 28, 2009 8:55 p.m. Toyman01 Reader

Damn! you weren't kidding when you said you were ready to set the engine. Looking good!

If you put a little more tire on it it will look like a roller skate.

If you need a hand give me a shout.
May 28, 2009 9:07 p.m. P71 Dork

I'm in love! Sweeeet car and nice fabrication work.
May 28, 2009 9:13 p.m. tuna55 New Reader

OK, your rear suspension is confusing me, which isn't that hard. What is the bar running diagonally from where the panhard bar meets the shock mount (weird, btw, but cool) to the chunk? Brian
May 28, 2009 10:51 p.m. Luke Dork

That's awesome. Very impressive stuff.

I like how far back you've set the engine.
May 28, 2009 11:57 p.m. BobOfTheFuture Reader

wow. looks like you could fit another motor in there infront of the first
May 29, 2009 6:51 a.m. Jensenman SuperDork

Thanks!

The front rotors are vented, the rears aren't but I will be adding ducting all the way around. It already has front ducting, it's visible in the front engine pic. I left it in place so I can plan my sway bar/radiator etc mounting around it. The wheels are the Bassett low inertia steels with the huge holes in them so I don't think I'll have a problem getting air out once it gets in. Yes, all 4 are 13x10's.

The bar running diagonally on the axle housing is a triangulation brace for the Panhard mount on the axle housing. You can see the end of the tube in the pic of the left shock mounting. The lower shock mount is about 2" inboard of the Panhard mount, to remove the lower shock mount bolt the PH has to be disconnected and lowered. I flipped the calipers to the front of the axle so the Panhard could be as long as possible so the axle won't move side to side a whole bunch as it goes up/down in relation to the chassis.

For right now, the majority of the engine wiring will be the stock RX7 harness, it's made so that it comes out of the car separate from the main harness and plugs directly into the ECM. That will make that part a lot easier, I just have to fab the harness for the power and ignition side of the circuits which should be pretty simple. The other wiring for lights etc I will do myself.

The story goes that when this car was on the drawing boards Donald Healey and Kjell Qvale planned ahead for a V8, and I believe it.

I'd like a 20B too, there's definitely enough room for it! It would put the engine higher and move weight further forward, though. Not to mention there just ain't enough wallet. I am seriously considering a 13BT, it will fit in the same spot as this motor and make ~240 HP with minimal mods; I have sourced a front mount intercooler already.
May 29, 2009 7:05 a.m. curtis New Reader

Jensenman wrote:

I am seriously considering a 13BT, it will fit in the same spot as this motor and make ~240 HP with minimal mods; I have sourced a front mount intercooler already.

I second this notion. You can also make more then 240 on a turbo engine with minimal mods. I mean just slap a good exhaust on the 13bt and you get quite a bit, that plus an intake, front mount, a couple fuel pieces, bigger secondaries (like gsl-se ones) , a fuel cut defender, pump and regulator. All on stock ECU or megasquirt it for that little more. i ran this same setup minus the squirt on my turbo 2 and put down more then 240 i can tell you that.

But then again you get the Na done right and youll have a revhappy engine that even with less power should have a nice crisp powerband that will make that jensen scoot. or 300 hp 13bt w/e. haha
May 29, 2009 7:27 a.m. Jensenman SuperDork

Another reason I am seriously considering forced induction: an N/A motor can lose a LOT of oomph over a 500 foot elevation change, like a hillclimb and it's much worse with a carbed engine. At least this 13B is the S5 FI motor and shouldn't lose as much power with elevation change as a carbed motor. The 12A in the Abomination does pretty well at the start but generally by the time I'm near the top I start trying to trim my toenail in the fan. If I'm going to make the 2 Minute Club at Wolf Ridge I'm gonna need a little help. If I go 13BT, I'll need to work on smoothing out the 'hit'.
May 29, 2009 8:48 a.m. alfadriver HalfDork

Here's the link to the breakers I found- http://www.spemco.com/circuit+breakers.aspx?product=136 is the actual ones that I have- all 7amp, but hopefully, this link shows the all of the mini ones- http://www.spemco.com/Circuit+Breakers.aspx

With the size, they are easy to mount on simple panel. Oh, and the price was right- less than $2 apiece. Well below what I could find anywhere else.

I only wish I could pull the breakers to turn the circuits off, but that's ok- I can always unplug what I don't need. But since those are $20 apiece, I can deal with the savings.

Eric
May 29, 2009 9:30 a.m. Jensenman SuperDork

Thanks for the link! Those are pretty cool.
May 29, 2009 9:40 a.m. John Brown SuperDork

Eric (and Jens) Instead of unplugging what you dont need why not build the system so that the entire array is powered by a single high amperage relay to the array of breakers then to micromini switches then LEDs to indicate power?
May 29, 2009 10:31 a.m. Jensenman SuperDork

(head explodes)

My plans were to run toggle switches with indicators and either fuses or breakers. That way each switch would have a fuse right with it. The toggles would control low amperage circuits to turn relays on/off for high draw stuff.
May 29, 2009 11:38 a.m. alfadriver HalfDork

Jensenman wrote:

(head explodes)

My plans were to run toggle switches with indicators and either fuses or breakers. That way each switch would have a fuse right with it. The toggles would control low amperage circuits to turn relays on/off for high draw stuff.

High draw stuff on your car.... starter, horn. That's about it. If you wire the indivudual head lights as individual breakers, they won't draw too much (I have each at 7amps, no relay). I'm sure you'll have a fan- so that'll need a relay, too. Oh, there is a turn signal relay- but just to flash the lights....

KISS. Even with 4 breakers for the lights, I still only have 8 used breakers on my car (10 are there- just in case).

E-
May 29, 2009 12:28 p.m. John Brown SuperDork

Good Point Eric.
May 29, 2009 12:31 p.m. Jensenman SuperDork

I was figuring relays for stuff like the ECM, cooling fan, headlights (yes it will have lights!) and fuel pump. I like the idea of separate controls for all of those but of course I'll have a main kill switch. I'm keeping the wipers as well, I am on the fence about a relay or relays for that. I will probably just wire that direct, since the switch I found is rated at 30 amps and to use relays I would need to either get a really freaky relay or run two of the 'ice cube' types (one for low, one for high). The wipers won't get much use (I hope).
May 29, 2009 1:10 p.m. alfadriver HalfDork

Forgot about the ECU.

But for the most part, you don't need a relay for all of that, even the fuel pump isn't a high draw item- the orignal pump on my alfa was on only 7amps.

Rad fan for sure, as well as horns, and starter (assuming you don't have a high draw button to use). But separate circuits keep the rest of the draw low. I almost had one for the fog lights, but just deleted them.

1)- main right 2) main left 3) high right 4) high left 5) fuel pump 6) reverse light, gage power, and SPICA switch (FI), turn signal 7) wiper. 8) brake lights and parking lights 9) (opt)- heater fan.

I'll probably add a system for an electric fan, too. You'd add a 10th for ECU power.
May 29, 2009 4:54 p.m. Jensenman SuperDork

With an ECU, I am most concerned about voltage drop rather than switch overload. I bought some no-E36 M3 switches rated at 25 amps from Pegasus a while back, while they are very good quality switches IIRC they have a higher voltage drop than the 30 amp Bosch relays. BTW, the Bosch relays are the only ones worth a rip; spend the extra money.

I have one of those noisy MSD pumps, it's supposed to draw an average of 10 amps.

I will be using one of those high capacity starter switches with the rubber boot, the same thing is in the Abomination without a relay and it works well so I'll just copy that again.

Also, RX7 alternators have a goofy '+' indicator light output which on the normal car energizes a relay which powers all kinds of crap. If using a charge indicator light, about the only way to do it is to convert that to a '-' output, so you can tell at a glance if the charging system is working. I'm not so much concerned about the alternator output as I am throwing a belt and not knowing it, that would lead to overheating whis is A Bad Thing.

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