boardkid280z

Just to put Tony's comment in perspective, 125mm is 5" exhaust (not sure whether the TT setups are sequential or what). And 444kW is about 600hp. I work at Lindsey Racing and on the 4 cylinder 944 Turbos we build (2.5L-3.0L), we recommend 4" over 3" on anything over 300hp because you will notice a difference. Around 300-400hp you're not going to have as much of an advantage in peak hp and torque so much as how soon it comes on. Ref: http://www.lindseyracing.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=LR&Category_Code=951EXHAUST4INCH We noticed an increase of about 10ft/lbs of torque at 390 peak and the horsepower didn't change much (it's actually lower with the 4", but it was 7 degrees hotter that day). BUT - "by 4000 RPM, the engine was making 75 more Ft. Lbs of torque at the wheels. It makes more torque all the way up the graph. Also note that the engine reached it's peak torque 350RPM sooner on the graph." So, with a larger exhaust - on a turbo, you'll have more power lower in the rpms and you'll increase your peak power output by a marginal to significant amount.

Frank, from some things I've read in the research I've done, it is not a good idea to use any liquid to cool a supercharger if you are running the compressed air through an intercooler. The liquid may vaporize in the heat of the SC, but it will probably 'liquidize' in the intercooler when the air cools off. Then you'll have puddles/pockets/whatever of liquid in the intercooler, which isn't good, especially if it's fuel. So cooling/lubing of the SC should only be done if it is going directly into the intake manifold. Any other more educated responses on this? A thought: I was planning on using water/alcohol/methanol/fuel to cool the air from my SC (JCR kit) right before or after the SC. Is it OK to use anything besides fuel to lube/cool the SC spraying before or into the SC? Or will water damage the SC any more than fuel?

Anything with boost is going to put the stock L24 to shame. Great looking car! As mentioned, we'll be curious to see if you have any hood clearance issues with that sweet azz IC. I'm sure it would be more of a problem with a 4.5" intercooler.

I think your nomenclature is causing a lot of problems in the understanding of your situation and your understanding of people's suggestions. Firstly, what kind of gauge are you watching? Are you talking about a mechanical gauge you have installed ini the dash, if so, is it one of these? A) C) Or are you talking about one of the gauges in Megatune with your laptop connected. If so, what is the name of the gauge? "Engine Vacuum", "Engine Vac Boost", "Engine MAP", ... Secondly... where, EXACTLY, is the vacuum gauge connected. If you are reading off of megatune, where did you connect the Megasquirt MAP vacuum hose on the engine? And if you are using a secondary mechanical vac/boost gauge, where, EXACTLY, is the signal line for that gauge connected on the engine/intake manifold, intake pipes, throttle body, whatever. Thirdly, you talk about how at idle you are at 19in or so of vacuum, this is good. Then you say as you increase the rpms, up until 4500 or so, your vacuum reading (notice how I didn't say vacuum pressure, because that doesn't make sense since those or contradictory terms) goes down. It sounds like this is while you are driving, and when I picture it, I picture the vacuum gauge going from 19inHG down towards 0inHg, which is atmospheric/ambient. The throttle blade is a restriction which creates a vacuum in the intake manifold, as you open the TB to increase RPMS, whether driving or in neutral, you are removing the restriction and your vacuum will go down. (you won't have as much vacuum, ie the vacuum number will be lower, 19inHG -->> 0inHG). With a turbo, once you hit 0, the engine is no longer sucking air through the turbo, but the turbo is now pushing air into the manifold/engine. That is called boost/positive pressure/pressure above ambient. Once the turbo is forcing air into the engine, you don't say negative vacuum, you say boost. I know you know all this stuff, but I'm trying to clarify the terms and names you are using for the different situations, since what you are saying is very confusing. For example, a)"without the turbo engaged" - did you remove the wastegate arm so the wastegate is always bypassing the turbo? or did you just not push the throttle down enough for the turbo to spool up? if your vacuum records negative values, you are producing boost, so the turbo was engaged. If it was hesitating (choking/sputtering), you may have been really lean when you were in boost. c) You should really figure out why you are blowing the injector fuses, check all you wiring, Ohm it out whatever. If you have it setup like we did with 3 fuses for the six injectors, you are losing fuel to 2 cylinders when that happens, that's very bad if you are under boost like you said. Make sure you have your PWM settings right, so you don't burn up your injectors. Also, what are the AFRs when all this is happening, when you are explaining stuff, mention if you were at 13:1 or 19:1 or whatever. This is more valuable info than anything else. As for your last post, that doesn't make any sense at all. What do you mean, "I can keep the turbo from turning on", to me this means you are keeping it out of boost, or keeping the MAP (manifold air pressure) below ambient, ie in vacuum. Then you say the pressure goes above ambient - this will not happen if the turbo is "off". If the pressure goes above ambient, very easy to do on an incline with a turbo, your turbo is "on". Dang, sorry for making this so long, but it didn't seem like this thread was making any progress in fixing your problem. Maybe you can post where you live and if anyone is local to you and has turbo experience, they might be willing to meet up and help you out. If you have ANY questions about this post, make sure to ask for clarification, or you can PM me. If this is all stuff you know, sorry for the long explanation.

Well, I was planning on using some type of TBI setup for my first iteration of getting the supercharged engine running. The TBI would just sit on top of the supercharger with a spacer. So the scoop would just force air into the TB. And the scoop butterflies wouldn't actually be functional. You could have one with the two or three butterflies that just open along with the actual throttle, or you could just have a scoop that scoops and filters, with no butterflies.

Sorry, I wasn't entirely clear there. I was assuming the 6 injectors in the runners would be for fuel, but I was wondering if you had any intentions of using the 7th injector for "cooling injection" using a fluid besides gasoline, like water, alcohol or methanol. Thinking about the hood clearance issue, I was searching for different scoop possibilities and came across some pics of the classic blower/carb scoop with 2, 3 or 4 butterflies sticking way up. You know a car's bad, when it's got one of these babies sticking out the hood: What if we applied the same principle to the Z, and I'm not talking about no V8 + blower + scoop setup with the scoop sticking straight up out tha middle. I'm talking inline 6, JCR supercharger kit, scoop with three red butterflies sticking out the driver side of the hood at a 45 degree angle. I photoshopped a little sample of what it might look like as follows: I might have to try it, comments? In fact I dare you all to dare me to do it, then I'll have to do it.

>>> ROFL >> Interesting.

So, are you just running fuel to the lone injector? Or will it be methanol, alcohol or water fed? I have a JCR kit that I'll be installing soon, and am still trying to figure out the whole fuel situation... I'd also love to see some pics of your fuel lines once they're all installed, should be a work of art. Any issue with hood clearance with that Ford TB setup?

Fuel pressure should be around 36psi, with the vacuum line disconnected. It will go down to 28-30psi when you connect the vacuum line. Mind, that's for a stock car, with a stock vacuum actuated FPR which will have a base fuel pressure that goes down under vacuum and up under boost. Hopefully your Mallory Unit will act similarly, because with boost, you kinda wanna make sure your FP goes up with boost.

Does this data look correct to everyone? I had a P90 head +Turbo on my L28 flattop shortblock before I threw a rod bearing. Then I swapped it all onto a L26 flattop block, been running 8psi boost for a while now no problems.

You should consider editing your second post in this thread if you really want the great folks of this forum to seriously consider your question and offer some useful advice. Like PJ says, there is usually quite a bit of discussion in this subforum, but at the moment it is kind of slow. And as far as knowledge base goes, like he said most of our collective know-how is focused on Zcars (hence the name of the forum). Your car falls outside of that range, and although it is a Nissan, most of us will need a little more info to help you out properly. What engine does it have? Displacement? It sounds like you want a roots style blower rather than a centrifugal style SC, which will involve either a) building an intake manifold to mount the SC on, or mounting the SC on a "stand" that you can route inlet and outlet air pipes to. Option a) might not be to hard if you can somehow adapt it to the intake manifold where the carb sits. But option would allow for intercooling, but would basically rule out carbs. Which brings us to fuel delivery. Draw through carbs should work I think. Same idea as a TBI unit, which is what the JCR kit came with for the Z. If you want full control though, you might consider Megasquirt, or if you have big $$$ some other fancy standalone. Which would bring injectors into the picture as well as the possibility of water/alcohol injection instead of intercooling. Full timing control is nice too, no need for a timing retard device. Running the SC long term should not be a problem, since they are stock parts right off other factory cars. But if you do buy a used one (not rebuilt/new) you never know how long it will last. As far as $$ goes, I'm not sure you could do SC cheaper than Turbo, that's seems like a false assumption.

Here's a few pics of my car: (The car has been lowered a bit since these pics were taken. I guess that means it's time for a new photo shoot) And me (last year sometime, helping a friend pick up his 77 280Z 2+2):

Update?? Any driving under boost yet?

So, how much difference do you think there will be in weight between a 'complete 2.8 turbo engine' and a 'complete 2.4 N/A engine'. If you take into account 20lbs for the turbo... you'll be pretty darn close. Throw in another 20 for the wiring/ECU/... and you can add an estimated 0-40lbs to your 390lbs base figure. So in response to your first post, after compiling the info Tony so kindly supplied, your engine to be shipped will weigh approximately 400-450lbs. If you are not familiar enough with these engines and couldn't make this deduction, maybe you should use kinder words to request an explanation of someone's 5 minute response to your 'searchable query'. Dang, 5 minutes, that's almost emergency response time quick... some people have to wait days to get a response to questions like this.

I've been a member here and at zcar.com for a long time. Last summer, we turbo'd my '78 with parts off an 81 ZXT (it was toast). Mods include: - Megasquirt 1 v3.0 - larger turbo compressor off a Buick Grand National - 3 inch downpipe and full exhaust - intercooler - stock N/A shortblock with flattop pistons and P90 head combo - sweet billet blow-off valve I've only been running 8psi or so, since it has flattops, and the stock turbo injectors and I haven't gotten a wideband on it yet to make sure my Air/Fuel ratio is OK. It runs good and pulls hard from 2800RPM on. Here is a video we made when we just got it running. I just made a YouTube account and this was the first video I uploaded, so I wanted to go ahead and make good use of it. Enjoy.

Looks great, Sounds like it's running pretty smoothly.

Just out of curiosity, how did you determine what portion of the head needed a vent tube? We have a steam vent kit for the 944 Turbo heads, but only because we noticed upon inspection of the inside water passages of the head that there was evidence of steam bubbles eroding the water passage walls.

It looks like I'll be using Joe Gibbs Racing Oil XP4 (equivalent to 15W50) (since that's what we sell at Lindsey Racing). Anyone have a suggestion on an additive that will have some good anti-sludge detergents? It sounds like the Joe Gibbs stuff will have the zinc, phosphorous and sulfur additives taken care of, but lacks any detergents since it is a race oil. Does that Lucas Oil Additive have detergents?

http://www.ka-t.org/forums/viewtopic.php?t=27681 How soon do you plan/hope to have it on the road 1FZ?

What is the cheapest oil (and easily available) with sufficient Zinc ppm?

I wonder if your brother's using a TPS like signal to control the position of the blow-off valve according to the position of the throttle...

Tony, got any pics of your Corona?

Why is your idle timing so high? Shouldn't it be close to what the stock setting is, mine is between 12 and 15 I think, stock is 8 or so.

Looks great! Any concern with hood clearance on the turbo's, or baking the paint off the hood with that much heat right underneath?

it's gonna be called a reducer, and you will probably want to find a silicone one, although plain ol' rubber would work fine if you can find one at HD.