[Kolvry]

I’m looking for a 96-99 vr4 to buy currently I used to have an sl but wanted an actual vr4. Anyway what is the stock hp and boost that the bottom end can handle?

 

[Albert0]

A stock 2G setup would be like 250hp at the wheels, I think most guys agree that a stock bottom end can support around 400hp, from that any issue with knock is less forgiving and you could start breaking things (first weak points is the pistons, our rods could last more) and also you are getting near the stock drivetrain limits, mostly the output shaft connection, most recommend going with 300m components.

 

[TurboSinceBirth]

You can make over 600whp on a stock bottom end 93-99 motor but it definitely isn't for everyone or the average results. You really need to have a solid tune in that respect, constantly monitor for knock, and be aware of any little changes in performance of the motor, sounds, oil pressure, etc. That said you can get a nice 400-450whp on pump gas and bigger TD04s with a stock bottom end. Throw on heads and cams and that'll net another 100whp. Run pump + meth or E-85 and you can run over 500whp. I wouldn't honestly push it much further than that in order to give you a safety margin of error. The piston ringlands will break first with detonation so it really is all in the tune. A flashed ecu with Chrome works just fine.

Since you'll have a 6-speed you won't need any 300m components. That's only on the 5-speeds that it's necessary. Plenty of 700-1200whp are running stock output shafts on the 6 but just about everything else is upgraded including billet shift forks, billet endcase, billet midbrace, billet bell housing brace, and so far no solution for upgraded transfercase gears that strip. I've run 5-600whp on an all stock 6-speed just fine with no issues and so have plenty of others. Just don't go crazy with 7k clutch dumps or lauches on slicks at the track.

 

[Kolvry]

You can make over 600whp on a stock bottom end 93-99 motor but it definitely isn't for everyone or the average results. You really need to have a solid tune in that respect, constantly monitor for knock, and be aware of any little changes in performance of the motor, sounds, oil pressure, etc. That said you can get a nice 400-450whp on pump gas and bigger TD04s with a stock bottom end. Throw on heads and cams and that'll net another 100whp. Run pump + meth or E-85 and you can run over 500whp. I wouldn't honestly push it much further than that in order to give you a safety margin of error. The piston ringlands will break first with detonation so it really is all in the tune. A flashed ecu with Chrome works just fine.

Since you'll have a 6-speed you won't need any 300m components. That's only on the 5-speeds that it's necessary. Plenty of 700-1200whp are running stock output shafts on the 6 but just about everything else is upgraded including billet shift forks, billet endcase, billet midbrace, billet bell housing brace, and so far no solution for upgraded transfercase gears that strip. I've run 5-600whp on an all stock 6-speed just fine with no issues and so have plenty of others. Just don't go crazy with 7k clutch dumps or lauches on slicks at the track.

I’m definitely planning on doing everything correctly and making sure everything is being supported properly. Just was wondering how much I’d be able throw at it before I need to rebuild the bottom end. Looking at maybe getting the Brian crower stroker kit and just pulling the engine and doing a full rebuild

 

[TurboSinceBirth]

I’m definitely planning on doing everything correctly and making sure everything is being supported properly. Just was wondering how much I’d be able throw at it before I need to rebuild the bottom end. Looking at maybe getting the Brian crower stroker kit and just pulling the engine and doing a full rebuild

It's really going to depend on the tune. Knock will kill it in a heartbeat whether it's 300 or 500whp. If you get someone to get a solid safe tune on it that has built many of these cars before at upgraded power levels, then you'll be plenty fine with 450-500whp pretty safely for awhile. You could maybe get by with higher power on a TD05 setup vs TD04 since it'll hit full boost a 4k rpms and have much less mid range torque and cylinder pressures but realistically it sounds like you aren't too familiar with these cars. I would say go for a 15G 400whp setup or 19/20T 450whp setup on pump gas and be done with it. The BC stroker kit is way overkill unless you plan to push more than 750wtq where the stock forged crank can start bending. Save your money and go with a Stage 3 Pampena shortblock. It'll handle anything you can throw at it by the sounds of what you're doing. Pampena Motorsports Stage 3 Engine

 

[Vince_Cuts_Vinyl]

You can make over 600whp on a stock bottom end 93-99 motor but it definitely isn't for everyone or the average results. You really need to have a solid tune in that respect, constantly monitor for knock, and be aware of any little changes in performance of the motor, sounds, oil pressure, etc. That said you can get a nice 400-450whp on pump gas and bigger TD04s with a stock bottom end. Throw on heads and cams and that'll net another 100whp. Run pump + meth or E-85 and you can run over 500whp. I wouldn't honestly push it much further than that in order to give you a safety margin of error. The piston ringlands will break first with detonation so it really is all in the tune. A flashed ecu with Chrome works just fine.

Since you'll have a 6-speed you won't need any 300m components. That's only on the 5-speeds that it's necessary. Plenty of 700-1200whp are running stock output shafts on the 6 but just about everything else is upgraded including billet shift forks, billet endcase, billet midbrace, billet bell housing brace, and so far no solution for upgraded transfercase gears that strip. I've run 5-600whp on an all stock 6-speed just fine with no issues and so have plenty of others. Just don't go crazy with 7k clutch dumps or lauches on slicks at the track.

I'm looking at a safe pump (only 91 in California) build on my 1991 VR4

And known issues with the 5spd?

Sent from my LM-G850 using Tapatalk

 

[TurboSinceBirth]

I'm looking at a safe pump (only 91 in California) build on my 1991 VR4

And known issues with the 5spd?

Sent from my LM-G850 using Tapatalk

The output shafts can break and strip at stock power levels and also the transfercases have cracked/broken as well. It's a crap shoot rolling the dice because you don't know how fatigued the cast aluminum is over 30 years. Preloading the drivetrain and not really launching it will go a long ways. A 300m OS and transfercase brace would be really nice to have but still won't completely save your transfercase. It'll just make it a matter of time before it breaks. The only solution is billet front and mid cases. I run LIPP 304SS front and mid housings on my 5-speed with a 300M OS but they don't make those cases anymore. You'll have to go through Rvenge for what you need: https://www.rvengeperformance.com/product/3000gt-dodge-stealth-billet-transfer-case-5-speed/.

I ran a 6-speed for awhile so I wouldn't have to spend $2-3k upgrading the transmission/transfercase at those power levels on a 5-speed but I also never really launched my car either which could have potentially split my bell housing. I've since got a fully built 5-speed with all the diffs and a fully built transfercase too. All the info you guys need is here on the forums in plenty of threads if you search.

 

[Kolvry]

It's really going to depend on the tune. Knock will kill it in a heartbeat whether it's 300 or 500whp. If you get someone to get a solid safe tune on it that has built many of these cars before at upgraded power levels, then you'll be plenty fine with 450-500whp pretty safely for awhile. You could maybe get by with higher power on a TD05 setup vs TD04 since it'll hit full boost a 4k rpms and have much less mid range torque and cylinder pressures but realistically it sounds like you aren't too familiar with these cars. I would say go for a 15G 400whp setup or 19/20T 450whp setup on pump gas and be done with it. The BC stroker kit is way overkill unless you plan to push more than 750wtq where the stock forged crank can start bending. Save your money and go with a Stage 3 Pampena shortblock. It'll handle anything you can throw at it by the sounds of what you're doing. Pampena Motorsports Stage 3 Engine

Will all the 6g72 parts go into this block?

 

[ThatOneVr4]

More people run 5 speeds for the drag strip. I'd choose the 25 spline over the 18. I sent my transfer case to Chris at Rvenge to put a hardended spool on the transfer case. I've done about 15 runs at the local dragstrip, with the 2 step banging at 5K rpm. No issues.

As far as engine goes, I've seen the 93+ stock ends handle 700+ it can be done but won't be good longterm for daily driving. 500awhp should be plenty for most folks.

 

[TurboSinceBirth]

Will all the 6g72 parts go into this block?

Yes it's a 3.0L 6G72 block. You have to send in a block and crankshaft as a core.

 

[Boricua-PR]

Back in the day when I started loking for more HP, I fried pisto #4 about three times, all because how are engines are designed. After I learned a few things, and got a good tune, I was able to get about 600awhp with stock bottom end and with the DR-800 turbo kit. Yes it was on stock block, but with 720 injectors, dual fuel pump kit and a bunch of other mods. The stock 5-spd couldn't handle it so I went 6-spd.... all the way from tranny to rear diff.
Never launched over 5000rpm, you don't need to, but bellow 4000rpm the car will bug down. About the clutch, the best I ever had was the 6-pucks RPS carbon-kevlar compound.

So, with stock bottom end you can have about 600-awhp with a good turbo kit, all the supporting mods and a good tune, and still have daily driver capabilities.

 

[Vince_Cuts_Vinyl]

@TurboSinceBirth
@ThatOneVr4

While I am experienced with mechanical stuff, I'm more domestic like Ford and JDM like kawasaki and Suzuki....

Is there a wiki that explains 304SS, 300m and what came with 18 or 24 spline and what that entails?
I keep hearing about an output shaft and like the DR800 turbos... Not a clue what some of it means.
I'm still trying to wrap my head around the TD04 stuff, like 9b 13b thats fine... But HL and some of the other things are out of my experience.

It's also a strange car.... Something like my 70 firebird with a holly double pumper I have no problem... That's all mechanical with springs and cables.... A rack of carbs on my bikes is easy as well.... I'm actually an IT guy and have been able to work on my 14 F150 ecoboost.... But the VR4 is fuel injected and vaccum operated... But unlike my my truck it lacks the computer or sensors for someone not experienced in this platform

I keep reading 318 and 3si... But I still get a lot of stuff that has me scratching my head. Like why would I need a billet Xfer case? I've never heard of that cracking in anything... And if I recall we have getrags?

Anyway.... I need a wiki or to pick the brain of someone experienced

Sent from my LM-G850 using Tapatalk

 

[ThatOneVr4]

@TurboSinceBirth
@ThatOneVr4

While I am experienced with mechanical stuff, I'm more domestic like Ford and JDM like kawasaki and Suzuki....

Is there a wiki that explains 304SS, 300m and what came with 18 or 24 spline and what that entails?
I keep hearing about an output shaft and like the DR800 turbos... Not a clue what some of it means.
I'm still trying to wrap my head around the TD04 stuff, like 9b 13b thats fine... But HL and some of the other things are out of my experience.

It's also a strange car.... Something like my 70 firebird with a holly double pumper I have no problem... That's all mechanical with springs and cables.... A rack of carbs on my bikes is easy as well.... I'm actually an IT guy and have been able to work on my 14 F150 ecoboost.... But the VR4 is fuel injected and vaccum operated... But unlike my my truck it lacks the computer or sensors for someone not experienced in this platform

I keep reading 318 and 3si... But I still get a lot of stuff that has me scratching my head. Like why would I need a billet Xfer case? I've never heard of that cracking in anything... And if I recall we have getrags?

Anyway.... I need a wiki or to pick the brain of someone experienced

Sent from my LM-G850 using Tapatalk

As far as the 300m was a aftermarket upgrade to make the shaft stronger. The billet xfer case looks nicer and is stronger. Most people run the stock transfer case but use a transfer case brace, along with a transmission bellhousing brace.

9b is the smallest turbo, then there was an 11g 13g, 15g, 16g(TDO5) 19t. The if you see something that is HL like a 19t-HL the HL refers to the smaller wheel on the turbo. It's bigger then the standard wheel and will flow more air. I might be forgetting things. I'm sure someone else can chime in and correct me.

 

[rossb]

what came with 18 or 24 spline and what that entails
I keep hearing about an output shaft and like the DR800 turbos... Not a clue what some of it means.

The output shaft is the 18/25 spline thing people keep talking about, the 300m is a hardened is like the hardened beefy big brother of the stock output shaft.
You car is a 91 and will have the 18 spline output shaft. I think the transition to 25 spline was towards the end of the 92 model year.
Dr800 turbos aren't made anymore, that I know of. Either way they are/were TD05 turbos which would require new exhaust manifold to run.

I'm still trying to wrap my head around the TD04 stuff, like 9b 13b thats fine... But HL and some of the other things are out of my experience.

9b is the stock turbo, 13g are slightly better flowing turbos and actually came stock on the EU vr4s. As for designations like "H" and "HL" those are referring to the compressor housing size, with HL being the biggest. Common HL turbos are 20ts or similar. TD04HL turbos usually have slight fitment problems on our cars due to the radiator fan and motor mounts.

But the VR4 is fuel injected and vaccum operated... But unlike my my truck it lacks the computer or sensors for someone not experienced in this platform

I'm not even sure what this statement means? Are you referring to the fact that the fuel pressure regulator uses vacuum? Because it isn't that uncommon.

 

[TurboSinceBirth]

A lot of questions you're asking Vince pertain to obselete/discontinued items. The LIPP stainless steel front and mid 5-speed transfercase housings were an option offered through 3SX a long time ago. NoCar was the first to come up with a billet 7075 aluminum front case, LIPP came up with the front and mid, Broomfield did a front and mid billet 7075 aluminum, and now more recently PCT has made some billet 7075 front and mid cases that are sold through Rvenge Performance. These 5-speed cars are getting pretty old and if I was going to be pushing anything larger than a 15G TD04 400whp setup, I'd probably jump straight to a billet transfercase. Yes it's a pricy upgrade but used transfercases in good condition are going up in prices now. A brace is only going to last so long. It'll probably keep it together in one piece but it won't keep it from cracking which ends up ruining it anyways. Cast aluminum fatigues over years with all of the vibration, heat cycles, and age. The 6-speed transfercases have an iron front case and don't break apart but before you ask if you can put a 6-speed on a 5-speed and have the best of both worlds, no you can't. It would take an extensive amount of machine work.

The DR-800s were also a Garrett T3 turbo. I have the compressor and turbine wheel inducer/exducer dimensions somewhere around here because I owned them but they're a really old tech turbo. Matt Monett made 714awhp with them tapped out a long time ago. Here's a pic:

There's much better turbo options now with the GTX gen2 variants, G25 turbos, and Xona Rotor turbos. You just about have to go with a custom set of manifolds but if you can get them in a v-band in/out configuration for the turbine housings, IMR does sell a twin turbo manifold kit for $3k. I've seen lots of mixed reviews about it and the company though. They're chasing Evo and Stinger custom performance parts mainly.

The TD04, TD04L, and TD04HL is the turbine side. There are different size turbine wheels. Think of it like the exhaust on your muscle car. Are you going to go dual 2", 2.5", or 3" exhaust? The bigger you go the more power you'll get even though it's sort of relative since naturally aspirated engines have to have some exhaust backpressure but turbocharged engines don't because the turbine wheel itself creates the most backpressure in the whole system itself no matter how big you go before or after the turbo. The stock TD04 turbine wheel doesn't really flow a whole lot. Boostmoore sells some 19Ts that use the stock turbine wheel and they're really huffing and puffing to get to 500whp. Typically you won't get that high. The TD04L turbine wheel can make over 500whp but likely not much more than 550. DR-650s have a clipped TD04L turbine wheel and due to the clipping it cheats to flow more at the high end but I don't think those have ever made over 550. TD04HL is the largest turbine wheel and you can make over 700whp. DR-750s have a 4 degree clipped HL turbine wheel with a 20T sized inducer/exducer compressor wheel(all other dimensions are custom compared to a 20T wheel). So it really all depends on how much power output you want to make and if you have all of the supporting mods for it. Personally, I wouldn't pushing more than probably 450whp. You can get that and keep a relatively stock car. Past that it starts getting expensive. Once you want a bulletproof bottom end for the engine past 5-600whp, then it gets exponentially higher in cost for everything you have to upgrade on the car.

If you want to start looking at some of the TD04 turbo sizes and compare the mm dimensions on the compressor and turbine side, then go to Kinugawa's website: KINUGAWA TURBO - Powered by Network Solutions.. If you want the best priced and so far already proven for 10s set of the largest TD04 turbos, go check out Arashi: Mitsubishi Turbo Journal Bearing 3000GT Anti-Surge. If you don't want to food with any of the minor coolant line, motor mount, and fan modifications to fit these larger compressor housings then you can go with the legendary DR-650 or DR-750 tried and true turbos. The 650s have a 16T inducer and 19T inducer so it's a custom compressor wheel and of course is a clipped TD04L turbine. Both have a lot of thought and design that went into them and I've owned both. Hopefully that gives you some information to make some decisions.

 

[Vince_Cuts_Vinyl]

@TurboSinceBirth
That's very helpful indeed, many thanks.

To be frank the vr4 is my slow car, but it's exceptionally cool because it's a VR4 and with a few bolt on parts it won't be my slowest (any more.)
I'd like to build a reliable 91 octane setup without going into the motor.

At this point I have an old car with 230k and known light scoring on 2 if the rear cyls. Everything else seems fine, but I'm trying to get it running reliability and restore everything else then in going to build it as described above and move on to my next project.... If I mess up this motor I'll rebuild it but again a safe street tune.

I refuse to run E85, California has 91 as premium I want something reliable that spools quick. My driving is usually sporting
/freeway at 75-100 but I occasionally go twisty roads too.

What would you recommend for that kind of build. Bonus points if you know what can be used in a 2 bolt and all the supporting mods.

I'm spurious on working then building this car, but I also own 2 businesses so my cars get worked on slowly

Sent from my LM-G850 using Tapatalk

 

[TurboSinceBirth]

Since you’ve got a stock 2-bolt motor and don’t plan on tearing into it to freshen it up, then you’re a lot more limited on what you can safely run due to the cast crankshaft you have. I honestly wouldn’t run more than 400-425whp through it so 15Gs are the best all around pump gas turbo for what you’re looking at. If you at least freshened up the motor, put in a forged crank even with the stock pistons and rods, and just did a re-ring job I’d say go with some 19Ts on pump gas. You could get close to 450whp.

You’re pretty heavily limited by that cast crank. I’ve seen some guys run race gas and make close to 500whp but that’s playing with fire IMO. I wouldn’t even advice running water/meth or E-85 just because you can’t take advantage of the extra octane, boost, and power. You’re looking at intake, downpipe, boost controller and gauge, datalogger, wideband, clutch, 15Gs, 550cc injectors, GM MAFT, and I think that’s roughly it but I may be forgetting a simple item or two. You can do a 400whp build start to finish on 15Gs for about $3-3.5k in parts. It’s pretty simple.