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5/6M-GTE vs. 7M-GTE

  • I did a 5/6M and wish I'd have done a 7M-GTE swap

    Votes: 0 0.0%
  • I did a 7M-GTE and I'm glad I went with that over a 5/6M

    Votes: 0 0.0%
  • I did a 7M and still have residual nightmares from all the wiring....should gone 5/6M

    Votes: 0 0.0%
  • I'm planning on a 7M, because (post reason)

    Votes: 0 0.0%

  • Total voters
    2
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Discussion Starter #1
Well, I've been scheming/dreaming/planning ('cause that's all my broke ass can do right now :D) and I was running some ideas off a buddy of mine. Originally, my plan was to do the turbo the 5M, then rebuild a 6M when the 5M gives up the ghost and go from there. I was planning on the Split Second MAF conversion, 295s, the works. Well some I did some math, and I was coming up around 2 grand all told. My buddy was thinking that a wrecked MKIII could easily be had for less than that.

So.....lets weigh out the pros and cons of 5/6M-GTE vs. 7M-GTE. Aside from the hellacious wiring nightmare that I will have (which I really am not afraid of), what would be the benefit of going with the 5/6M? It seems to me that it would end up cheaper in the long run to get the whole car, as I can sell off what I don't need (my old 5M, MKIII rear end, interior, etc). Plus, I want to use the tranny from the MKIII either way, so that's taken care of. Any thoughts? I'm pretty sold on the 7M swap at this point, anyone care to change my mind back, or solidify my thoughts further?
 

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As far as the wiring goes Reg Rimer can make you the harness you need.

I was thinking about the same thing before I started my project.

For me I guess I like having a car with all the #'s matching. I think that they are comparable in total cost. I havent figured up what it is gona cost me to complete this project but it is goign to be WAY over $2000, and that is using a used CT26 and standard pistons. I did have an expensive machine shop do my engine work but I wanted it done right. I am also putting on adjustable cam gears and redoing all my vaccume hoses in blue. At least that is the plan.

Just do yourself a favor and rebuld whatever engine you get. Be prepared to spend over $2000. It all seems to add up. Go slow when you do it and put all the bolts in labled ziplock baggies. You will thank yourself later.

Good Luck.
Mark
 

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well, my donor car cost me $1k and was complete running and driving. it had been rearended badly. it already had an hks 2mm mhg. then i spent about another $1500 to put it in including the 3in o2 elbow, dp, exhaust, muffler, boost and a/f gauges, oil filter adaptor, hks smf air filter, stage 3 clutch, wiring adaptor harness, oil, ,filters, hoses, misc. items, ,the gauge cups, coolant, eclipse, bov, etc.. all in all its not bad, and you have much more room to grow on the stock internals. you can do the lexus 550 mod and should be good to well over 400rwhp on stock internals as long as it is tuned properly. plus the ecu will control the a/f ratios much better then a 5m or 6m ecu ever can even with a piggy back computer.hth.
william
 

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Go with the 7m-gte. I did the 6m-gte and while it was ultimately successful, cost in the end after all bugs worked out was well into the range of just having Don Culbertson do the whole 7m transplant for me and never get greasy. Plus I'm stuck at 7-8psi with no aftermarket support and lets face it, a jury-rigged fuel and ignition system. I've had it up to here with these dicey add-on systems and now am saving my money for a standalone programmable ECU. Only two reasons I didn't do 7m-gte in first place 1) I lived at the time where I didn't have room to keep a mk3 donor for the duration and 2) I was scared of the electrical mess. This was before I'd ever met Don and before Jim King and Andy S. wrote up all the info on the web. Using a 6m block only came about because I didn't want to turbo a 150K mile 5m and I just decided to buy a 6m core for rebuild.

What you could look for is a running/driving mk3t thats mabe rough or badly rusted out for under $2K, make sure everything is good to go while its in the mk3 chassis, and then swap everything over. Minor plumbing fabrication and miscellaneous stuff will add another $500 to $1,500 and then you're still under the cost of a 6m-gte done right considering piece-by-piece salvage yard prices. Now you've got a 7m-gte with toyota engineered reliability and at least some aftermarket support if you want to mod it.

Phil D.
 

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Discussion Starter #5
I added a poll so people can vote what they did/want to do. I'm hearing lots of good feedback on the 7M swap, not so many pro's for the GTE swap. What does Reg Rimer get for a harness, and how much for a computer? I still think getting a whole car is the plan though.
 

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Ditto what Phil said.

However, I do give Phil major props for doing the 6MGTE!

The key for transplant is a properly working donor 7MGTE. And time. And money. And a very good condition MK2.

One should have done performance mods already to the MK2.
This includes suspension and brakes.

If the donor 7MGTE is in an unknown state, you will spend more time and money to get it to run correctly.
 

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re: reason

I voted for the 5/6M. Reason being that this is what MKIIs came with, and for me adding a 7M/1JZ/2JZ would be changing the soul of the car too much. Props to everyone who has done it or wants to do it, but for me it changes the character/lineage of the car too much. 5/6M are what MKIIs came with and that's what mine will have when it gets turbo'd :) Besides, at full bore I think the two valve head engines sound alot better than the 4 valvers do too :)

Sonny
 

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Discussion Starter #8
I've already put a different "heart" in my car, so I wouldn't be too broken up about doing it again :). The 7M just sounds much more cost effective, and also a better platform to work from.
 

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i was planning on doing a 7M swap into my blacky this summer but MSS hit and it hit bad (whity). it did take good part out of my 7M swap money thats why im gonna have to wait and build up some more to do it right
 

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anybody ever heard of a hemi?

:D thats right hemispherical valve heads thats all i can say about the 5/6mge!!! no 4 tiny little valves. but 2 can be enlarged valves. ahu thats right. i think their all the same blocks is that correct. don't remember, but can put h-beam rods in them and forged pistons aswell. anybody can have the heads ported for max flow. camshafts CAN BE MADE for them just have to know the right source! and be happy with reprocussions of the performance wanted no performance camshafts is going to idle like a stocker unless its a stocker improved piece(junker another words) with no power improvement except the band in which is produced at different rpms maybe! everyone you need to think about how easy it is to do these mods, and if your not familiar with high performance cars with v8's( ones that have choppy idle) they don't drive like they did stock :) . if you want the power out of the 5/6mge you can obtain it. don't fear those who go to "bigger is better" not always the right choice, and can be very expensive to poor people with little time. any way thats just my thoughts on the question of whats a better option. :wink: :idea: if all else fails head studs thicker hg and reallyyyyyyyy good intercooler you could run lots of boost on a 5mge same rods as 7m i do believe. but i'm not a perfect person just done lots of cars and lots of turbos for imports and domestics oh ya f.y.i. most stock bottom end motors can handle about 15 psi of boost!!! not all but most. balance the bottom end before and you'll be much more likely to succeed were others have failed with the 5/6m's when mine is finished i will give full details on its performance and is "sale" after completion.
 

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Discussion Starter #11
I'm thinking it's all about the fuel system of the 7M, it's way superior for a boosted engine. It will end up being cheaper too. And really, I don't want this to turn into a 4 valves vs. 2 valves debate :p. 7M heads are Hemi's too, IIRC.
 

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re:

4 valves are simular but the efficiency is off due to the effects of how the a/f moves in the cylinder the 4 valves with extra valves interups the flow design of a piston engine
 

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Discussion Starter #13
Re: re:

turbofreek said:
4 valves are simular but the efficiency is off due to the effects of how the a/f moves in the cylinder the 4 valves with extra valves interups the flow design of a piston engine
none of this matters when boost is involved.
 

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More valves increase the "window" at which air flow starts geometrically.

Also, smaller valves create less physical disturbance for air flow.

However, the 5M head has physically nicer flow characteristics.
 

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Reg's wiring would set you back a grand and you have to supply the wiring to him. It makes since to go this route if you already have a mk3 turbo otherwise have Don or Jeff do the swap.
 

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Discussion Starter #16
I'm thinking I will do this myself. I will have a garage and covered car port next year, and lots of time, so I can go slow and mark everything. I may end up actually enjoying it :)
 

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Sam,

I have to agree with Phil D, tho for a different reason than he stated. To really do a 5M-GTE RIGHT (and when I say right, I mean as right as one can accomplish with the limited after market supprt we have), it's pretty spendy. All said and done, to really do my 5M where I felt I am not gonna blow up the motor the first time I hit boost, have some reliability, and keep the longevity that the original 5M had, I am about $4,000 on just the motor. Add in a stronger clutch (thats gonna compromise driveability), suspension to handle the extra power, fuel delivery mods and a replacement rear (because its a WHEN I blow the rear, not an IF), I'll probably be sitting at ~$6K... When I started this endevor, I estimated that I could do this for about 2K...

Now comes the 7M figures... Donor cars can be haed at insurance auctions left and right, for between 700 and 1500, depending on the condition of the car. Add in another 1500 for miscelaneous parts, and your still a damn site cheaper than what mine is costing... Plus you have a motor that the aftermarket makes parts for, and you don't have to spend near as much time modifying parts to work as you do sourcing and installing them.

Do I think a 5M or 6M with a turbo is a reliable or decent motor? If its done right, sure do. Do I think its as high on the "Bang-for-the-buck-ometer"? Hell no.

And as for the guy who said that he wanted to keep the "Linieage" of his car true.. Ya do know that the 6M is a 5M with a longer throw, and that a 7M is a 6M with a 4 valve head?
 

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re:

7Ms do not have a hemispherical combusion chamber. They have pentroof combustion chambers, and although they are a somewhat similar to hemis, they aren't the same thing.



And as for the guy who said that he wanted to keep the "Linieage" of his car true.. Ya do know that the 6M is a 5M with a longer throw, and that a 7M is a 6M with a 4 valve head?
:roll: thanks. I always just figured that the engine codes all had the letter "M" in them and were numbered sequentially in increasing order from oldest engine design to newest engine design was always just a funny coincidence............ :p

All kidding aside, I do know the relationship and history of the M engines Bob, you just missed my point. Some might also argue that a 2JZ is nothing more than a 7M with a superior head design and stoughter block, seeing as how they share similar design architecture, so why not use it? My point is (and this only applies to me cause this is how I feel, I'm not willing my opinion on anyone else here) is that to keep the car closer to what I believe a MKII is, and less of a MKIII/MKIV Supra hybrid (or hot rod for those who feel putting anything other than an inline six in a Supra is ok) I wanted to keep it with the basic engine configuration it had when it rolled off the factory assembly line. I'm not knocking 7Ms, and realize they are the evolution of the 5/6Ms, but they didn't come in MKIIs and therefore don't feel it belongs in my MKII. This is just my opinion and I was simply replying to the originator of this post as to the reasoning for my pole selection. Now then, back to my surfing.......

Cheers

Sonny
 

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Well, I've done both a 7mgte and now a 6mgte. The 7mgte is more work, higher costs but when it's done right it's a beautiful thing. Good power, reliable, good gas mileage and it will pass emissions. The 6mgte, on the other hand, is cheaper, harder to work on and there are alot of unknowns about how it if/might run before you even attempt to start it. And it's the unknowns that tend to take the excitement out of the project, IMHO.
 
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