mkiii 7m na....can i swap a 1ggte

[marc]

7m = love

bhg = sumthing liek a busted condom

[XTREMESUPRA]

thats why if u gone do a swap u better have a couple friends that can help u out or have a shop that can give u a descent price.

[supraman121]

the 7m i think has more upgrades and the engine is cheaper to repair do to the engine is more popular.

?how much does it cost to bore the 7m engine's cause im na all the way and i was woundering out much it would cost for that little bit of horsepower or tourqe?

[XTREMESUPRA]

7M = prone to HG failure, long stroke (bad for rpms), inferior engine management (old technology), poorly designed intake plumbing and exhaust manifold, prone to overheating #6 cylinder, an abortion of accessory belts which are poorly routed, stock head doesn't flow great w/o major work, horrible oiling system

1J = higher redline (7100), cleaner design, not prone to any of the failures listed above for the 7M, stock turbos prone to failure, hard to find SOME EFI parts, stock components can make 600+ HP and rev to over 8100 rpms that why i think 1j is better to start with

[Lambolica]

I'm from Australia so I'm not sure on the availabilities but...

Factory 7M-GTE power 232hp@5600 torque 240@4000
Factory 1JZ-GTE power 280hp@6200 torque 269@4600

Here (may be different there) but it is cheaper to bolt in a 1JZ than to rebuild a BHG 7M properly. The swap is as easy as swapping 1 7m For another if you do the research (you guys will need to extend the loom + swap some plug wires) the 1J is more fuel efficient, is quicker in stock form. And doesn't require HG replacement every 5000km. they both respond equally to mods, but the 7M fails at the HG more often than not adding additional rebuild costs.

You guys really seem to like your 7M's

[IHateHacks]

No possible way swaping a 1JZ is cheaper than repairing a head gasket on a 7M. Im $800 deep on my repair and that includes what you call "adding additional rebuild costs" such as valve work, planed the head surface, cleaning, checking head for warpage and cracks, lapping the block (which I did my self for free). Show me where I can buy a good running 1JZ with the ECU and harness for under $800 shipped and I'm sold. We only love our 7M's because they are cheaper to fix/buy than any other motor.
"doesn't require HG replacement every 5000km"

Yea neither does a 7M if you know what you are doing. You just slap a metal head gasket on any 7M old block with out lapping then you will be redoing it. The mating surfaces have to be equal to or better than when the block rolled out of the factory. You also can't use or reuse stock head bolts or the stock torque specs. You also must tighten the head bolts in a specific order and in 3 passes working your way up to the final torque spec. You fail to do any of this and you will be replacing that head gasket again.

"the 1J is more fuel efficient"

Who cares about fuel efficiency? News flash: turbocharged cars require massive amounts of fuel to maintain a healthy air fuel ratio of 11.3 to 1, prevent knock, pre-ignition or detonation which will blow a hole in your block or destroy a piston. I care more about the internals of my engine than a few cents in my pocket. Buy a prius if you want fuel efficient bragging rights.

[Lambolica]

Yeah... Like I said you guys in the US may be able to get the 7M's back up and running cheaper than finding a 1J. Here 7M's are the more expensive engine and are generally harder to find.

Here is my story. Note this is in Australian Prices. Origonally the Car was bought ex Japan with 90,000km (~55,000 miles) MA70 GT Limited Aerotop. when first landed the head bolts torque was checked and tightend. Things went fine for 6 months until summer came. Several succesive 40 degree C days (105 deg F +) later came home from work, had a shower, went to go out, shtarted the car and it belowed Smoke... Joy. I did know this was comming but there were none of the symtoms normally associsted with BHG. the car was shut down and towed to a mechanic for testing, Low compression on 5 & 6 and milkshakes in the oil tray. After looking around for a quick fix replacement engine none were found that were in the price range (ie was looking for somthing to get it on the road as it is a daily driver whilst the origonal engine was rebuilt) the Supra ended up sitting for a few weeks while some pricing on parts was done and the pricing on a 1J converion was done.

The desision was made to go 1J and the 7M was sold to a mate who was looking for a cheap 7M to rebuild for his Crown Wagon. when we pulled the head off the HG was blown between 5&6 water to oil gallery & cylinder. the engine was stripped down the head sent off to get machined and the valves set, the block was pulled down the deck machined and bores rehoned, ARP stud kit was sourced, Metal head gasket sourced, the water jackets had the corroded areas re welded up and ground smooth before the deck was machined and the block was tested for cracks. The relevant costs for the rebuild as follows:
Head rebuild and machining - $1450
ARP stud kit - $550
block machining - $350
MHG - $850
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Total $3200

Note that the timing belt, front and rear main seal & cam seals were replaced and all new fluids were also sourced but these happened on the rebuild and the conversion so these costs are not included in the comparison.

Whilst the 7M was being stripped and sorted a 1J half clip was sourced and picked up. the reason at the time that the 1J was decided on was the MA70 was origonally Auto and there were always plans to convert it to Manual. The half clip came with an R154 so it was a case of kill 2 birds with 1 stone. the 1J was pulled from the clip swapped into the MA70 and the wiring done. the conversion took 2 weekends (3.5 days) from moving the MA70 onto ramps and pulling out the 7M to test driving the 1J.

Price for front Clip $ 3000
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Total $ 3000 (plus free Manual conversion)

To be fair if the Supra was already manual the rebuild of the 7M may have happened, but even then we could have got an auto 1J clip for $2200 and sourced a 1J bellhousing for less.

the 2 Cars were dynoed at a dyno day event the Supra turned 172rwkw as converted (stock ECU, I/C, Factory Boost). the 7M turned 181rwkw only mod was big beefy intercooler. Both cars had exhaust work done.

12 Months down the track the MHG gasket let go again and the engine was rebuilt again in the same fashion except forged pistons, bottom end bearings were done and the CT26 was rebuilt and High flowed. this time a composite HG was used. Costs were $2500 for the HG rebuild, $1500 for the turbo, $1800 for the bottom end.

The Supra has had the Clutch changed as it always slipped and a Dyno tune to improve the A/F.

The recent dyno event the 7M pulled 191rwkw running stock boost still. the Supra ran 195rwkw after the Dyno tune still stock boost. Granted when both these 1J and the 7M get boosted the 7M should come out on top. but bang for buck the 1J wins hands down in costs over the long term.

In terms of dyno results stock vs stock the 1J has more power.
Basic breathing mods they are very equal
when severly worked the 7M starts to come out on top (this is the displacement showing) but no-one drives around in a 340rwkw car everyday for very long. for most Aussies both engines are stock, then boosted, from there the breathing is improved and tuning tweaked to get 200rwkw where most of us are happy to use it everyday. there are some 300+ 7M and 1J's here but they are pretty much drag cars only and spent most of their time getting stuff fixed (usually gearboxes, diffs and clutches) but few of us really have the money to throw 5 or 10 grand at a car every year so reliable power is the key. and 7M unfortunatly don't scream reliability.

That being said I don't have a great deal against 7M's there are 2 that are currently getting built 1 in a Soarer, 1 in a MkII the soarer is getting about 350rwkw and the Supra owner is aiming for 400rwkw + but isn't on the road yet. The 1J's tend to hold all the drag records, and the 2J dyno cars are just insane (560+rwkw)

My 2c

Cheers
Simon