Twin turbo or single?

[8gsofresh]

@SPD_FRK thanks for all your insight

maybe 700Hp is a bit outta reach......for now ha

and i guess i'll be selling a set of heads soon lol
thanks again

[qnz]

I know there was 1 club 3g member who has twin turbo v6. That was about 3+ years ago

[8gsofresh]

It seems all the info i need is here just not organized very....

[beam514]

It seems all the info i need is here just not organized very....

that's because typically the people that come here and ask about twin turboing their Galants actually have no clue what they're talking about (not referring to you, I'm talking about in the past). There also hasn't been much in HIGH performance here, though obviously there is still some. Club3G seems to have just a tad bit more of the bigger number stuff.

That said, I hardly know anything about turbo's, so that's all I have to contribute :P

[SPD_FRK]

@SPD_FRK thanks for all your insight

maybe 700Hp is a bit outta reach......for now ha

and i guess i'll be selling a set of heads soon lol
thanks again

700hp really isn't necessarily "out of reach," but the final results of such a build just would not be street friendly or anywhere near "mild" for the streets. The heads will be fine for 500hp as we have seen those running into the 500+ mark. The only problem was how restrictive the heads were, even with boost pressure in the low to mid 20s. With the advancement on the 6g series engine platform now, the 6g75 heads have been proven to flow comparable to that of the Chevy LS1 heads (keep in mind they are a V8), that shows how capable the newer 6g75 engine is for either N/A or Forced Induction. We have already seen 400whp with I believe 8-10psi of boost in the MIVEC 3.8L. Granted the MIVEc does have a higher lift at 4000 RPMs when the MIVEC engages, but this is why I suggest running the Non-MIVEC heads as we can easily run a set of RPW Stage 3 cams with a high lift at all RPMs.

The only other thing I want to mention here is (and unfortunately you have already purchased them) is the forged rods. We have seen the OEM 6g72 rods hold up to 20psi of boost making roughly 400whp, and the OEM 6g74 rods are holding into the 500+ whp mark, there is more information on the rods Here. Having the aftermarket forged rods is not really a "bad thing," but unless you are really pushing into the 550-600hp mark it may be a bit overkill to an extent.

I know there was 1 club 3g member who has twin turbo v6. That was about 3+ years ago

I figured there was at least one in the Eclipse community who did the modification, just never saw much on it. From the time and research I spent for the TT plan on the 75 I did find it was pretty straight forward to build, just double the cost in a sense lol.

[Galant306m]

Someone put 3000gt heads on their engine and boost it before i do

[8gsofresh]

Well the idea is to get as much hp out of the motor with out breaking any thing so that the reasoning behind the forged rods I've seen a 3000gt with 1300+ Hp a 6g72tt just wondering why no one has tried to build a 8g like that

i figured with a larger displacement i could get pretty close to that with less boost

[SPD_FRK]

Someone put 3000gt heads on their engine and boost it before i do

It would work, however with the engine orientation of the 3000 GT being 180* opposite of the 6g series engines in the Galant and Eclipse, the engine rotation is also reversed...meaning the cam timing is most likely not going to work too well I imagine. There is always the option of the DOHC heads from a an XG350 though...but that requires the distributorless ignition system.

Well the idea is to get as much hp out of the motor with out breaking any thing so that the reasoning behind the forged rods I've seen a 3000gt with 1300+ Hp a 6g72tt just wondering why no one has tried to build a 8g like that

i figured with a larger displacement i could get pretty close to that with less boost

Well as it stands currently the most ever pushed (on this platform) is still held by a Galant at 531WHP. Not too many people have come close to that, and for a number of reasons besides the money investment. The vehicle at this point pretty much becomes one of two things, a track queen or a dyno queen. Things begin breaking more, tuning is vital, and any tiny issue becomes amplified to something major which ultimately leads to damaging effects if not resolved.

The 3000 GT platform is widely seen with higher HP numbers, even for a street vehicle simply due to the AWD setup versus the FWD setup we deal with. Anybody could certainly spend the money and build an 800hp engine setup for the Galant or Eclipse, but with FWD it is pretty much useless except for burning off tires.

[Galant306m]

Meh cams will still spin the correct way....

[M-Rod]

do it mitch!

[Stewi]

+1

There is no need to run that low of a compression ratio if the motor is being built specifically to handle the boost. I run 9.5:1 compression on my 4G64/63 setup and 21psi on regular 93 pump gas. You should have a compression ratio of at least 9:1 Its not like your trying to hit 1100whp and your running 42psi. As far as turbo's are concerned, If I were you I would be looking at the FP HTA86 or 88 or a precision 6765 DBB setup. Both those turbo's will spool up nice even with a .82A/R hotside and pull like hell to redline assuming you can get the heads to flow enough for that. Also definetly consider what your doing with the car, if your building it to chase a dyno# thats fine, but it might not be much fun to drive after that

[Galant306m]

Hmmm ill see if travis wants to build a tt dohc 9g

[mysticj]

Don't know if the 9G engine bay has room for a DOHC head, well with the deck height of the 6g74/5 anyway.

Crank sensor and wheel aren't a problem on the 9G ECU but the finding a way to mounting the 9G cam sensor on the DOHC is a problem.

Adapting the W5A51 and AWD system from the Endeavor is not hard but will the auto tranny hold out to the torque output.

[Galant306m]

Meant 8g lol stupid phone

[SPD_FRK]

Don't know if the 9G engine bay has room for a DOHC head, well with the deck height of the 6g74/5 anyway.

Crank sensor and wheel aren't a problem on the 9G ECU but the finding a way to mounting the 9G cam sensor on the DOHC is a problem.

Adapting the W5A51 and AWD system from the Endeavor is not hard but will the auto tranny hold out to the torque output.

I am not sure, but don't the 75 heads still outflow the DOHC heads? It would be more of a "cool factor" to run a DOHC than something more perfomance capable don't you think?

As for the AWD stuff, well it is possible to use Evo T-Case and 2nd Gen A/T GSX parts...still just waiting for Pharmicis and their "source" to make the necessary bellhousing "kit" to swap over from the OEM 3g M/T bell housing.

As far as turbo's are concerned, If I were you I would be looking at the FP HTA86 or 88 or a precision 6765 DBB setup. Both those turbo's will spool up nice even with a .82A/R hotside and pull like hell to redline assuming you can get the heads to flow enough for that. Also definetly consider what your doing with the car, if your building it to chase a dyno# thats fine, but it might not be much fun to drive after that

This is probably just personal preference...but then again with the business I work in we are running journal bearing turbos with excellent results. I would personally suggest finding a turbo that is not ball bearing for a couple of reasons. First is the ability, should the occasion arise, to rebuild the journal bearing turbo cartridge wheras the ball bearing turbos have to be sent into the manufacturer to be rebuilt (read higher cost). Second reason is the shafts on the journal bearing turbos are generally (Specifically the Borg Warner line) is much "beefier" and an excellent choice for its overall durability. Spool up time on the Journal bearing turbo vs ball bearing (from what I have seen from my work) is maybe 200-300 RPMs later, but you have to just weigh the advantages/disadvantages then really.

[Stewi]

I am not sure, but don't the 75 heads still outflow the DOHC heads? It would be more of a "cool factor" to run a DOHC than something more perfomance capable don't you think?

As for the AWD stuff, well it is possible to use Evo T-Case and 2nd Gen A/T GSX parts...still just waiting for Pharmicis and their "source" to make the necessary bellhousing "kit" to swap over from the OEM 3g M/T bell housing.


This is probably just personal preference...but then again with the business I work in we are running journal bearing turbos with excellent results. I would personally suggest finding a turbo that is not ball bearing for a couple of reasons. First is the ability, should the occasion arise, to rebuild the journal bearing turbo cartridge wheras the ball bearing turbos have to be sent into the manufacturer to be rebuilt (read higher cost). Second reason is the shafts on the journal bearing turbos are generally (Specifically the Borg Warner line) is much "beefier" and an excellent choice for its overall durability. Spool up time on the Journal bearing turbo vs ball bearing (from what I have seen from my work) is maybe 200-300 RPMs later, but you have to just weigh the advantages/disadvantages then really.

My personal preference is journal bearing as well (mine has been rebuilt a few times), but for his power goals and to keep the car streetable, you would want a ball bearing turbo. Plus his opening post was that money wasnt of concern, so if he has it to spend, let him spend it.

[Galant306m]

My personal preference is journal bearing as well (mine has been rebuilt a few times), but for his power goals and to keep the car streetable, you would want a ball bearing turbo. Plus his opening post was that money wasnt of concern, so if he has it to spend, let him spend it.

yea but..... Originally Posted by qnz
well there are talkers and there are do'ers. talkers never do. and do'ers never talk

[Stewi]

Lol