New to the forum and looking forward to some good info.
I have a 2002 Frontier with the VG33E. I have looked at a previous post on this site about building these engines and wanted to ask for some advice on parts, setup for future turbo charging and so on. The post I was looking at is the "VG33E - What can be done to this motor?" and it had some great info, but I need to know a little more.
What I am trying to do is take this VG33E to the extreme, getting the absolute most from this motor as I can. Supercharged intake system, headers/custom exhaust, head work, block work and in the end turbo charging the system are in the plan.
I want to do this build in 3 stages and make sure that each stage can handle what will be needed for the final goal.
1. Intake and Exhaust System
A. Intake: Here is where I immediately have run into trouble. Over bored TB and MAF are no problem here, but what about the intake plenum itself?? No one seems to make anything that will work. I hear that using the 2000 Pathfinder Intake will give much better flow, but I’m not sure if this is true. I do know it will fit, but that’s about it. Some guys have said that using an aftermarket Intake Plenum is the way to go for the best flow, but can’t seem to provide anyone that supplies them, which leads me onto my next question. If in the end I want to install a turbo or two on this system, should I be looking at this route anyway? I may be better off going with a supercharged intake. That truck did come in a supercharged model and I’m sure I could easily go that route… Anyone help me out here?
B. Exhaust Pretty straight forward here I think. Headers are a must, High flow CATS etc. Questions are… How much flow is needed here? Should I run two into one or true duals? What size pipe do I run? How much back pressure is needed? What headers would be best for this app? I only know of one company who has them. They are 3 into one with the collector @ 1 ¾ inches. I think that the headers for a Z31 would work as well, but not sure and I have not found any as of yet. Again keep in mind the final goal will be the addition of a turbo.
2. Block and Heads
A. Heads: Porting and Polishing… Possibly larger valves… Not really sure here. This is a weak point in my knowledge. There are some good cams available and adjustable cam gears that according to the previous post listed will make a big difference. Both are on the list for installation.
B. Block: Again, need all the info I can get.
3. Turbo: Adding this in the end will be a project in itself. The main thing for this post about the turbo is getting everything else in place and ready for its integration.
Of course an ECU reprogramming will be in order somewhere along the way.
I know it’s a long post, but from what I have read on this forum already I am in the right place for some good advice.
VG33E Build... Need some help.
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mtcookson
- Posts: 2923
- Joined: Thu Nov 21, 2002 12:43 pm
- Car: 1991 Nissan 300ZX
1992 Iinfiniti Q45
and much much more - Contact:
1A. The stock intake should work just fine. Stock, it is one of the best flowing intakes available on the SOHC VG. Port match both the upper and lower intake manifolds and port match the modified throttle body to the upper manifold and it should work great.
The problem with the manifold for the supercharged VG is that the supercharge itself is essentially the upper manifold. You have the lower manifold connecting both of the heads, then basically a plate that bolts to it, then the supercharger to the plate so it won't work as an actual intake manifold unless you were going to twin charge the engine (supercharger and turbo), which I don't recommend. Just stick with the stock intake and it should work just fine.
1B. When you go turbo, generally the manifold pipe diameter will be smaller than most NA setups would be (and probably even a supercharged setup). After the turbo, there's almost no limit. If you go single turbo... don't go any less than 3" all of the way back. Twin turbo, 2.5" from each turbo back should do fine.
No backpressure is needed at all. Its a common misconception that backpressure is needed for low end power. What is really happening is when you go to a larger exhaust you're basically just changing the tuning point of the exhaust. A smaller exhaust has great flow and velocity at low engine speeds but as the engine revs up it starts becoming more restrictive, increasing backpressure and decreasing power. When you go to a larger exhaust you gain your top end power back but sometimes the flow isn't quite as optimized on the lower end, which is why you can lose power down low with a larger exhaust. When you go turbo... this all goes out the window. You almost can't go too big on the exhaust with a turbo. Reason being, the less back pressure you have on the exit side of the turbo the quicker it will be allowed to spool. This gives you better low end power as you have more air, sooner.
2A. You can get larger valves, Ferrea makes 1mm oversize, stainless steel valves for both the intake and exhaust. I believe that's about as big as you can go without running into problems. Generally... I think a good port and polish with some good cams designed for a turbo setup will benefit you more. If you're going all out, it wouldn't be a bad upgrade but probably not absolutely necessary.
2B. Not much truly needed to be done here depending on your power goals... but after some recent discoveries there's actually a lot you can do if you want. Turns out, the VG33's have some super thick cylinder walls, about .300" thick. As a comparison, the VG30 has roughly .177" thick cylinder walls. This means, you could actually bore your VG33 out to around 98 mm and still nearly retain the same thickness as the VG30 cylinder walls. This gets you right under a 3.8 liter VG (3,756 cc to be exact).
You don't have to go that high, not by any means. Stock, the VG33 with boost is an absolute torque monster. I've seen one example making nearly 500 ft. lb. of torque to the wheels on a stock internal VG33 with a turbo. At that point, I'd probably consider going with some forged pistons. Stock size or larger, your choice. Either way they'll likely have to be custom so you can get them made how you want. BRC Performance is a popular company for the SOHC VG crowd for custom pistons. The most common route is to have them make the piston to your specifications based on stock, but with a larger wrist pin hole to match the VG30DETT rods. The DETT rods will bolt right up to your crank, no problem, but the wrist pin is just slightly larger in diameter. If you get your pistons made to use those rods, you could pick up an inexpensive set of Eagle H-beam rods for the VG30DETT for less than 600 dollars and would have a very strong bottom end.
As far as compression ratio goes, I'd keep it at 9:1 or less. Depending on your power goes, if they're somewhat high, less would probably be a bit better.
3. Here you first need to decide if you want to go single or twin turbo. Each has their own benefits. Single will be cheaper but depending on where you want it in the engine bay, exhaust pipe routing can get difficult. Twin works great on V engines as it reduces the amount of exhaust piping but it does, generally, increase the amount of intake piping quite a bit and you generally need about double of everything for it so they are a bit more expensive.
Once you decide which route you want to go there, we can move on to turbo selection. To kind of get that kicked off a bit... what kind of power level are you looking for?
Finally, are you interested in tuning it all yourself or having a dyno shop tune it or do you want a pre-programmed ECU? If you're interested in the tuning part of it, take a look at Nistune. Its pretty much the best, and one of the only, tuning setups for the SOHC VG ECU's. It gives you the power of a standalone for the cost of a reprogram and even some piggy back units. Definitely worth looking in to.
The problem with the manifold for the supercharged VG is that the supercharge itself is essentially the upper manifold. You have the lower manifold connecting both of the heads, then basically a plate that bolts to it, then the supercharger to the plate so it won't work as an actual intake manifold unless you were going to twin charge the engine (supercharger and turbo), which I don't recommend. Just stick with the stock intake and it should work just fine.
1B. When you go turbo, generally the manifold pipe diameter will be smaller than most NA setups would be (and probably even a supercharged setup). After the turbo, there's almost no limit. If you go single turbo... don't go any less than 3" all of the way back. Twin turbo, 2.5" from each turbo back should do fine.
No backpressure is needed at all. Its a common misconception that backpressure is needed for low end power. What is really happening is when you go to a larger exhaust you're basically just changing the tuning point of the exhaust. A smaller exhaust has great flow and velocity at low engine speeds but as the engine revs up it starts becoming more restrictive, increasing backpressure and decreasing power. When you go to a larger exhaust you gain your top end power back but sometimes the flow isn't quite as optimized on the lower end, which is why you can lose power down low with a larger exhaust. When you go turbo... this all goes out the window. You almost can't go too big on the exhaust with a turbo. Reason being, the less back pressure you have on the exit side of the turbo the quicker it will be allowed to spool. This gives you better low end power as you have more air, sooner.
2A. You can get larger valves, Ferrea makes 1mm oversize, stainless steel valves for both the intake and exhaust. I believe that's about as big as you can go without running into problems. Generally... I think a good port and polish with some good cams designed for a turbo setup will benefit you more. If you're going all out, it wouldn't be a bad upgrade but probably not absolutely necessary.
2B. Not much truly needed to be done here depending on your power goals... but after some recent discoveries there's actually a lot you can do if you want. Turns out, the VG33's have some super thick cylinder walls, about .300" thick. As a comparison, the VG30 has roughly .177" thick cylinder walls. This means, you could actually bore your VG33 out to around 98 mm and still nearly retain the same thickness as the VG30 cylinder walls. This gets you right under a 3.8 liter VG (3,756 cc to be exact).
You don't have to go that high, not by any means. Stock, the VG33 with boost is an absolute torque monster. I've seen one example making nearly 500 ft. lb. of torque to the wheels on a stock internal VG33 with a turbo. At that point, I'd probably consider going with some forged pistons. Stock size or larger, your choice. Either way they'll likely have to be custom so you can get them made how you want. BRC Performance is a popular company for the SOHC VG crowd for custom pistons. The most common route is to have them make the piston to your specifications based on stock, but with a larger wrist pin hole to match the VG30DETT rods. The DETT rods will bolt right up to your crank, no problem, but the wrist pin is just slightly larger in diameter. If you get your pistons made to use those rods, you could pick up an inexpensive set of Eagle H-beam rods for the VG30DETT for less than 600 dollars and would have a very strong bottom end.
As far as compression ratio goes, I'd keep it at 9:1 or less. Depending on your power goes, if they're somewhat high, less would probably be a bit better.
3. Here you first need to decide if you want to go single or twin turbo. Each has their own benefits. Single will be cheaper but depending on where you want it in the engine bay, exhaust pipe routing can get difficult. Twin works great on V engines as it reduces the amount of exhaust piping but it does, generally, increase the amount of intake piping quite a bit and you generally need about double of everything for it so they are a bit more expensive.
Once you decide which route you want to go there, we can move on to turbo selection. To kind of get that kicked off a bit... what kind of power level are you looking for?
Finally, are you interested in tuning it all yourself or having a dyno shop tune it or do you want a pre-programmed ECU? If you're interested in the tuning part of it, take a look at Nistune. Its pretty much the best, and one of the only, tuning setups for the SOHC VG ECU's. It gives you the power of a standalone for the cost of a reprogram and even some piggy back units. Definitely worth looking in to.
Re: (mtcookson)
Sweet u r the man!
Ok... It seems to me that setup for the turbo may be detrimental to my performance for the time I will be driving the truck before I actually move on to the turbos integration. At this time why don't we stick with the intake exhaust and head work only... Sound Ok?
1A. Can I do the port matching myself?
1B. A couple of things here. If I were to setup my exhaust for the turbo, I would loose low end power in my NA configuration correct? If this is the case, what would be ur recommendation for a NA setup keeping in mind the headwork and cams? I will redo the exaust again once I go turbo.
2A. The cams I wanted to use are the .473"/266 DEG supposed to be the biggest that will fit in the head w/o modification and great for mid torque on NA and turbo. What would u recomend? I will be using the adjustable cam gears as well. I will check into the 1mm oversized valves. I may as well add them now when I'm having my port work done. In the end I want this to be the the most extreme VG33E(T) possible. Is there anything special about the port/polish and valve job? I have heard that on these types of jobs there are certain methods that are prefered... Sorry I do not have anymore detail on that... forgot to bookmark
2B. This will be a little time in coming and definately another job in itself. I still have a good 100K miles left on my lower end and at this time will leave it as is. I will however get another short block in the meantime and start the mods as the money permits... and yes it willl end up a 3.8L.
3. To keep in line with this build, twin turbo is what seems to be appealing to me. I do have a concern though. There is almost no free space in my engine bay as it is from Nissan. How will two turbos and the piping needed fit? Will they possibly be remote mounted?
As for ur question of how much power I want, let's see what the limit is.
4. Do any upgrades need to be done to the Fuel/Ignition system somewhere along the way?
Thanks for the Nistune tip. I will look into that.
Looking forward to getting this build going. Thanks
Ok... It seems to me that setup for the turbo may be detrimental to my performance for the time I will be driving the truck before I actually move on to the turbos integration. At this time why don't we stick with the intake exhaust and head work only... Sound Ok?
1A. Can I do the port matching myself?
1B. A couple of things here. If I were to setup my exhaust for the turbo, I would loose low end power in my NA configuration correct? If this is the case, what would be ur recommendation for a NA setup keeping in mind the headwork and cams? I will redo the exaust again once I go turbo.
2A. The cams I wanted to use are the .473"/266 DEG supposed to be the biggest that will fit in the head w/o modification and great for mid torque on NA and turbo. What would u recomend? I will be using the adjustable cam gears as well. I will check into the 1mm oversized valves. I may as well add them now when I'm having my port work done. In the end I want this to be the the most extreme VG33E(T) possible. Is there anything special about the port/polish and valve job? I have heard that on these types of jobs there are certain methods that are prefered... Sorry I do not have anymore detail on that... forgot to bookmark
2B. This will be a little time in coming and definately another job in itself. I still have a good 100K miles left on my lower end and at this time will leave it as is. I will however get another short block in the meantime and start the mods as the money permits... and yes it willl end up a 3.8L.
3. To keep in line with this build, twin turbo is what seems to be appealing to me. I do have a concern though. There is almost no free space in my engine bay as it is from Nissan. How will two turbos and the piping needed fit? Will they possibly be remote mounted?
As for ur question of how much power I want, let's see what the limit is.
4. Do any upgrades need to be done to the Fuel/Ignition system somewhere along the way?
Thanks for the Nistune tip. I will look into that.
Looking forward to getting this build going. Thanks
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mtcookson
- Posts: 2923
- Joined: Thu Nov 21, 2002 12:43 pm
- Car: 1991 Nissan 300ZX
1992 Iinfiniti Q45
and much much more - Contact:
I'd actually just stick with the intake and head work to start, then when you're ready for the turbo do the exhaust since the manifolds will be completely different between the two setups... you could technically go ahead and do the turbo manifolds and bolt more exhaust piping to it instead of a turbo for the time being. It won't be optimized for NA performance but won't hurt it extremely bad.
1A. Port matching is rather easy so you can do it yourself. Pretty much all you do it match the manifold ports to the gasket so that they're all the same diameter.
1B. If you don't mind doing the exhaust twice, the optimal setup would probably be long tube headers (the length essentially tunes where your torque curve will peak), equal length if at all possible, and probably 2.5" piping back from the headers. I'm not fully versed in NA exhaust setups but I'm sure that would work pretty good. The only thing I'm unsure of is what diameter the headers should be. I know Doug Thorley Headers has a set for the older VG30 equipped trucks and they use a 1.5" primary.
2A. Those are the JWT S2 cams. They definitely wouldn't be bad, they're optimized for turbo setups but work alright with NA setups so that would be pretty good for you. If you wanted to go all out down the road, I'd probably consider a custom grind from a place like Isky, that way they can design the cam exactly how you want. I think its also a bit cheaper than JWT as well.
The best thing you can do on the port and polish is find someone that either knows Nissan's really well and has done some VG heads or someone at least with a flow bench so that they can at least make sure they're making it better. As far as what to do... I'm not really sure there as I haven't got into head porting yet.
3. Luckily when you go with a twin turbo setup, the turbos are generally rather small making it a bit easier to pull off. If at all possible, you'll want to keep them close to the block so that you can somewhat short manifolds. Equal length manifolds would be preferable but a log design will work just fine as well.
As far as power limit... the limit is just how much you want to spend really. The Electramotive IMSA GTP ZX was powered by a VG30ET and made upwards of 1000+ hp in qualifying trim. There are some street driven 300ZX's making nearly 500 horsepower to the wheels I believe one in Florida or something making well over that I believe. A 3.8 liter VG with a twin turbo setup would probably hit that rather easily with torque that could probably put some diesels to shame.
4. For the NA setup you might need a slight upgrade in the fuel system, but probably not too extreme. The tuning would be important though as that will allow you to extract more power. When it comes to the turbo setup you'll need to go all out. Large fuel pump, large injectors, all of that fun stuff.
Ignition wise, the stock setup is actually rather strong. You'll want colder plugs when you go turbo but other than that really the only other thing may be an MSD ignition box, but its probably not necessary. You could also get a different coil if you want to.
1A. Port matching is rather easy so you can do it yourself. Pretty much all you do it match the manifold ports to the gasket so that they're all the same diameter.
1B. If you don't mind doing the exhaust twice, the optimal setup would probably be long tube headers (the length essentially tunes where your torque curve will peak), equal length if at all possible, and probably 2.5" piping back from the headers. I'm not fully versed in NA exhaust setups but I'm sure that would work pretty good. The only thing I'm unsure of is what diameter the headers should be. I know Doug Thorley Headers has a set for the older VG30 equipped trucks and they use a 1.5" primary.
2A. Those are the JWT S2 cams. They definitely wouldn't be bad, they're optimized for turbo setups but work alright with NA setups so that would be pretty good for you. If you wanted to go all out down the road, I'd probably consider a custom grind from a place like Isky, that way they can design the cam exactly how you want. I think its also a bit cheaper than JWT as well.
The best thing you can do on the port and polish is find someone that either knows Nissan's really well and has done some VG heads or someone at least with a flow bench so that they can at least make sure they're making it better. As far as what to do... I'm not really sure there as I haven't got into head porting yet.
3. Luckily when you go with a twin turbo setup, the turbos are generally rather small making it a bit easier to pull off. If at all possible, you'll want to keep them close to the block so that you can somewhat short manifolds. Equal length manifolds would be preferable but a log design will work just fine as well.
As far as power limit... the limit is just how much you want to spend really. The Electramotive IMSA GTP ZX was powered by a VG30ET and made upwards of 1000+ hp in qualifying trim. There are some street driven 300ZX's making nearly 500 horsepower to the wheels I believe one in Florida or something making well over that I believe. A 3.8 liter VG with a twin turbo setup would probably hit that rather easily with torque that could probably put some diesels to shame.
4. For the NA setup you might need a slight upgrade in the fuel system, but probably not too extreme. The tuning would be important though as that will allow you to extract more power. When it comes to the turbo setup you'll need to go all out. Large fuel pump, large injectors, all of that fun stuff.
Ignition wise, the stock setup is actually rather strong. You'll want colder plugs when you go turbo but other than that really the only other thing may be an MSD ignition box, but its probably not necessary. You could also get a different coil if you want to.
Re: (mtcookson)
mtcookson, I am in the process of building this monster and wanted to ask a question. I am using the pistons from a VH45 as you stated in a prior post and wanted to know if you know how much needs to be notched into the pistons for valve clearance?
Intake and exhaust are already complete. Heads are beutifully ported and polished by DPR Racing in Gardena California. I am using the Jim Wolfe S1 cams. We are building the block as well using the VH45 pistons and I thought you may have some info on the how much of a notch is cut.
Thanks
Intake and exhaust are already complete. Heads are beutifully ported and polished by DPR Racing in Gardena California. I am using the Jim Wolfe S1 cams. We are building the block as well using the VH45 pistons and I thought you may have some info on the how much of a notch is cut.
Thanks
Re: VG33E Build... Need some help.
hey guys i was just linked to this thread and was just curious on how it worked out.. i just shot a rod and it amazed me because she wasn't knocking and has yet to knock. i fiured that since im goinge to have to pull the engine and rebuild it any ways that i might as well just up the power that she can put out. why waste the time and money with no incentive right?
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