mtcookson

Holset HX25... I just bought one and the exhaust housing definitely looks small enough for 1.5 liters to spool pretty quickly. I'm planning on putting it on a MR2 Spyder (1.8 liter) and it should work out pretty well. Going by Holset's specs, it should support up to 360 hp. Two would be a blast. They're a bit hard to find but are rather cheap when you do find them. I picked mine up in perfect condition with no shaft play at all for 245 shipped... it'll support as much power as the GT28RS for nearly a 6th of the cost. Definitely can't beat that.

a gt25r is quite small and 1.5 liters is within its opperating range. TTZ guys upgrade to larger turbos that than and i'm sure they spool up quicker than 5,000 rpm. something couldn't have been right.

That definitely doesn't seem right... there must've been something terribly wrong because there are larger twin turbo upgrades for the 300ZX (and the VQ shouldn't flow that much less than the VG... if it even flows less. it could potentially flow better really.) There must have been a boost leak or something major like that causing that problem.

They seem to have syncro issues on the earlier ones. I'm not sure of the power handling but someone mentioned to me that the Z32 5-speed matches the VH45's power band a bit better than the 6-speed did, which makes sense but at the same time doesn't... both Z cars and the VH produce their peak power and torque at a pretty close rpm (both Z's peak hp at 6,400 and the VH at 6,000 while the Z's peak torque is at 3,600 for TT, 4,800 for 350Z, and 4,000 for VH). *** In the end, I know one thing is absolutely certain... the Z32 5-speed has been proven to handle a lot of power. *** Just checked the gear ratios of both trannies. Oddly enough, the 5-speed is overdriven slightly more than the 6-speed making the 6-speed a rather close ratio tranny. That would probably make it good for a N/A setup but if you go with some boost on the VH, the 5-speed would probably be a much better choice, plus there's a chance you would get better gas mileage with the 5-speed.

Sent you a private message

just curious why you want to go with a twin setup... double the cost for little to no gains of anything. but to answer your question... from what i can figure out so far it looks like there might be a chance you would see some surging putting two of those on and it seems like it might take quite a bit of boost to hit the numbers you want. i'm not the greatest with compressor maps and haven't messed with trying to figure out how figure one with a twin setup so i may be totally wrong.

sent you a pm.

The DE(TT) crank will fit right into the VG30E. The major difference is the crank snout. It needs to be machined down to accept the oil pump, timing belt gear, crank pulley, etc. Some say to machine the pulley and such as well as the crank snout equally so not too much material is taken off of the snout.

Yeah, I was working with lost on that one. He is pretty difficult to get ahold of. Did you try sending him an email or a private message? It might take a little while for him to reply, he's always on and off it seems. Very awesome guy to work with though. He's definitely pretty cool.

I was helping put together the group buy but at the time there wasn't enough interest to get all 10 together. I think now there might be enough people to get all 10 or more so it could definitely happen now.

good idea

Sorry, I only have the one I'm using on my Maxima and another that I'm putting on the Z (the one I'm putting on the 300ZX is just a cheapy Skyline intercooler that I'm just using for slightly better than stock performance. Its not very big at all.)

This site has a bunch of links on the granger valve based boost controller: http://www.fwdmopar.com/sites/dennis/boostcontrolbible.html

for the most part they are the same (bore, stroke, bearing sizes, bell housing bolt pattern, etc.) but some of the differences are the head bolts locations (naturally since its sohc vs. dohc) and i believe the TT block has spots for oil squirters. i'm pretty sure that the oil/coolant passages through the block to the head are likely different but overall they're the same basic design.

very good point indeed

cast iron blocks. the vg30de(tt) engines are quite heavy... which is somewhat odd since the vg30e(t) engines are rather light weight for a iron block, aluminum heads v6. 84-86 vg30et is roughly 396. i've heard the vg30dett is well over 500 lbs.

ahhh, yeah... i didn't even think about that. thanks for the help!

This could potentially be a stupid question but I've never heard nor read anything about this particular subject before. Can a pressure plate be resurfaced like a flywheel can? Reason I ask is because a 300ZX Turbo I have has a SPEC stage 3 on it but the disc is pretty worn down. Its quite a bit overkill for this car as I'm not going to put a lot of power out of it since I'm going to sell it. Anyways, I'm wanting to do a sort of hybrid setup using the SPEC pressure plate (if it has more holding power than stock, as it should) and using a stock clutch disc. Should hold more power than stock and still retain good street manners. Anyone know whether or not this is possible and safe to do? Thanks in advance for any advice you can give me!

the thing may "only" make 350 hp but it displaces 7.8 liters... how much torque does that sucker make?? i would think it would make an insane amount of torque, which is where the tranny and clutch could have issues. Other than that (and the thing blowing to pieces) that would definitely be a unique and cool swap.

that's strange... the only thing i could possibly think of would be maybe that the hoses are too long causing a delay... but even then i had decently long hoses on mine and i never noticed any spiking. what type of mbc are you using and what type of wastegate?

The former... I always hear bad stories of centerforce clutches. Exedy is usually held as a very good clutch company.

I've actually done a cost comparison and it would be cheaper to swap it into a Z32 than it would an S30 mostly because of all of the suspension and drivetrain stuff needed for the S30. The Z32 pretty much has everything you need already.

Wouldn't happen to know how to calculator the frontal area would you? Does that include all front facing parts (windshield, hood, bumper, mirrors, etc.) or does it include something else? This definitely seems like a pretty cool calculator.

I've heard of some people having that issue with SPEC before. I like mine but I think the next one I want to try will be an RPS as I'm thinking about using one of their high dollar ones for the VH swap so I want to make sure their lower end ones are made just as well. I can never decide though. That's interesting about those trannies. I wouldn't have guessed that the Z31 tranny would have been so much shorter. I hate when they make changes like that yet keep the numbers the same.

Clutch: I'd probably go with a SPEC or RPS clutch. The SPEC clutches can hold a decent amount of power yet are still streetable. They have a "stage 3" that is the last sprung hub clutch (easier for street driving) before the racing type clutches for the 84-86 Turbo that will handle 515 ft. lb. of torque. I bought one of those for my Maxima and its pretty nice... definitely on the overkill side at the moment but hopefully down the road I'll make enough torque to need that. Tranny wise you should be able to use the 90-96 300ZX N/A 5-speed. The twin turbo version of that tranny is exactly the same except for where the starter bolts to the bell housing. There is slightly more material at that spot on the twin turbo version due to them using a 250 mm clutch/flywheel setup. I believe the 87-89 300ZX Turbo tranny is also the same as the those two but is more similar to the TT tranny is it uses a 250 mm clutch setup as well. Those trannies are definitely a lot stronger than the pos borg warner t5 in the earlier 300ZX turbo. The t5's definitely seem to have some serious issues with handling power... as do most borg warner trannies except for maybe the T5 world class and definitely the T56, but I've had nothing but headaches from borg warner's ****. Anyways... an aluminum flywheel is definitely a nice upgrade as would be an aluminum or at the least a one piece driveshaft to save some more weight. It just helps the engine spin faster and frees up more power in doing so. They also increase throttle response as well. I put one on my Maxima and it helped out in all of those areas. I'd probably run a full 3 inch exhaust if possible. On a turbo vehicle that usually frees up a good amount of power and allows the turbo to spool faster. I probably would run a muffler just to be on the safe side though. Wouldn't want to get pulled over for noise violation. A Magnaflow, Dynamax, or similar straight through muffler will give you the best flow. They're the louder of all of the mufflers but with the turbocharger aren't all that bad. I have a Magnaflow on my Maxima and there's only a certain spot where the exhaust drones but it is below the rpm I usually cruise at so it never bothers me at all. Aftercooler wise you don't want to go too big and don't want to go too small. I'd probably stick with an aftercooler that has a 2.5 inch inlet and outlet. I definitely wouldn't go any thicker than 3 inches. 2.5 to 3 inches thick should be more than enough. Dimension wise I'd first measure where you want to put it. On the 85 Z31 Turbo I'm working on, I'm planning on standing the radiator up and putting an aftercooler where the radiator was with some electric fans on both to be on the safe side. Once you find your measurements I'd base the size off of that. I wouldn't go overly big like the radiator big but slightly smaller than that should work pretty good. Also, you'll want to look at the flow numbers of the aftercooler you're looking at. Most of them will have a flow and/or power rating on them so that'll help you figure out which size works best for you. The best style of aftercooler core would be a bar and plate. They're much more free flowing than a tube and fin style which means less pressure loss and more flow. Here's a bar and plate: I have a couple tube and fin aftercoolers in the garage but have yet to take a picture of them. If I remember to I'll try getting some comparison pictures tonight. I believe the TSC that you're speaking of might be different than the one the turbo was sent to. If its like the one around here that I'm thinking of, they're more of just odds and ends supply, I don't believe they actually deal with any mechanical stuff like that. I'm not positive though. I would think a good diesel performance shop would be able to do something with it though. I'd call around different places in you area and see if anyone them do any sort of work like that.