Forced Induction Q45 Discussion

[sultan]

Stock q45 gearing good for 215? Sorry, I don't buy it

theoretical top speed based on tire size, rpm, transmission and rear end gears is about 220 in 4th gear at 7000rpm (if my calculator is accurate). put taller tires for more top end, 27" would make it 229. the gearings good but aerodynamics is the limiting factor.

obviously JWT ecu would be a good way to go for boost, but the SAFC II and e-manage both are supposed to work on the Q, but would only be to add more fuel or bigger injectors. e-manage has an ignition harness for timing retard but it doesn't work on V8's with coil on plug ignition unfortunately.

does the SC have the ability to be intercooled (easily)?

[1qckser]

http://www.zongoo.com/article1465.html

[AZhitman]

Great info.

dkill, we desperately need to talk before I call the CA guy back. I may just add him to the group buy list, take the original Eaton for myself and go from there.

[Nathan]

I think you guys are limiting yourself...6psi? I think you should run more like 12, intercooled. Of course you'd have to drop 8 new sidefeeds in and have JWT make you a program that could handle them, but man imagine what it'd be like. I think the ol' 4.5 could take it too, if a KA can handle 15psi and make 350whp, imagine what a Q engine could do...I think 12psi intercooled is well within possibility. The only bad thing is it adds significantly to the cost Oh, and you might be outrunning me at that point

[tonytgtr]

Nathan the problem with the q45 motor is the compression ratioof the piston. This is a 10:1 motor. I have sucessfully supercharged motors with this much compression the problems you run into. The heads gaskets usually let go. There were designed for N/A motors. The pistons literally melt. Hyperutecticpistons don't like being leaned out. Fuel system starts to lag or you detonate the motor they won't be around for long. Right now I am looking for a set for duaine they need to be forged. Looking for help here guys. Someone had mentioned about spark retard for COP set up. There gets to be a point where he have to leavethe factory computer and will have to step up to a new computer system. AEM, fel-pro, etc...

[HeavyDuty]

I'm offline for a week & all hell breaks loose here!!

Trying to catch up on all the forced induction posts, going to be a late night.

AZ, if you need a shop in Orlando to do any removal, measuring, shipping, mock ups, etc. please let me know. We're almost up & running 100% after the move.

Also, I found a VH45 from a 94-95? car that caught on fire. Great for mock up fitment issues.

I got a little distracted the last couple of weeks with a Pulsar GTI-R swap underway on my old 91 SE-R, got the motor Tuesday, 440 inj, Cobra MAF & a 50 shot.

Oh yeah!

[AZhitman]

HD - That's good to hear.

I may have you run over and grab the SC and ship it to me (I'll hook you up for the trouble).

[HeavyDuty]

I think you guys are limiting yourself...6psi? I think you should run more like 12, intercooled. Of course you'd have to drop 8 new sidefeeds in and have JWT make you a program that could handle them, but man imagine what it'd be like. I think the ol' 4.5 could take it too, if a KA can handle 15psi and make 350whp, imagine what a Q engine could do...I think 12psi intercooled is well within possibility. The only bad thing is it adds significantly to the cost Oh, and you might be outrunning me at that point

Too much pressure on the table of a cast piston for reliable power. Yes you could stud the head & make a different head gasket, etc, but tonygtr is right, the weakest link is the pistons themselves.

12 aftercooled psi would be yes, YES, YES!!!! Awwwww!:D

[Nathan]

Hmmm, I'm still not so certain 12psi isn't easily attainable. The KA I referenced earlier has a 9.5:1 compression ratio and also has stock cast pistons, the rods are sturdy but the ringlands on those pistons is a known weak point. I've firsthand compared my cast pistons to my Ross's and let me tell you, there is NO comparison, yet those stock cast ones have held up to some crazy loads. I kid you not when I know a person running 22psi on a stock block KA, I dont expect it to live long, but still...it so far is taking it. As long as you have adequate fueling and conservative timing, I dont see 12psi on such a nice motor being a big problem. This is why I mentioned upgraded injectors (I think 550's all around would do the trick) coupled with a JWT ecu tune. I dont remember offhand what the capabilities of a Q MAF are, but that too would be simple enough to fix with a Z32 MAF. Also, studding the head should be unnecessary, Nissan uses ridiculously good head bolts allready and while studs are nice...without detonation I really dont see the need. The JWT ecu has a history of being on the conservative side anyway so detonation shouldn't be an issue. Just dont go filling up with 87 octane gas I'm not trying to argue here guys...just bring another angle in from the crazier side of the Nissan world!

[Nathan]

Insanity

Is that really such a bad thing?

[Tgvince]

AH dreaming of a 600+hp Q....

Terry

[1qckser]

To get things back on track some good info

http://www.mn12performance.com...n.htm

[AZhitman]

I concur - I just want mine to give me a good, consistent added 50-70 hp.

That's not much to ask, but I really have no idea what kind of boost that corresponds to.

I want more power, but I want it to remain streetable and "wife-freindly".

[HeavyDuty]

287hp x 4 psi = 361hp

Rough calculations, for chrissakes, please no flames.

[AZhitman]

No flames necessary - I don't need EXACT numbers, but I think anything that'll give me 300 to the wheels will make me a damn happy camper.

[Tgvince]

No flames necessary - I don't need EXACT numbers, but I think anything that'll give me 300 to the wheels will make me a damn happy camper.

For a few weeks....HP is addictive my friend...especially when your talking boost:).

Terry

[AZhitman]

LOL - And soon thereafter I'll be talking transmission replacement and divorce lawyer.

[HeavyDuty]

For a few weeks....HP is addictive my friend...especially when your talking boost:).

Terry