MORE HORSEPOWER!!!

[Rex Rich]

MORE HORSEPOWER!!!

Yes one of the funnest things to talk about and something most people want! No?

I was an engine builder for several years a wile ago. My friends and I were always making our engines of all sorts a lot more powerful and because we had lots of them around we could try anything to make it happen. We also had lots of info floating around on how to get more power from an engine.

We were street racers, strip racers and circle track racers. There was one thing that we always agreed worked every time and was the first thing you needed to do. It was also the cheapest dollar for power!

Answer… mill the hell out the heads!

I would have good results going up to 11.2-1 comp on pump gas. Then all you had to do is add octane to get rid of the pinging if needed.That would not only add HP but also that much again torch!

Mill it off take it out and bust the axles off it! No kidding!

I wish I were an engine builder now, bumping the compression would be the first thing I would try on a Q45 engine. Then I would find the other bottlenecks in the system.

If the valves hitting the pistons were a problem then we would add material to the heads combustion chambers or the top of the pistons.

The problem with this well designed V8 (in my opinion and others with experience I knew, Nissan just made the best production engine design!) is that it seems that they may have tuned this engine to its near peak output and with a 10.2-1 compression ratio you would probably only be able to add a half point of compression? But even that would add up to a lot more real power compared to any of these air and exhaust mods people are doing?

With all the computer controls involved I’m not too sure how they would react?

Lets get some Q45 techs and others of interest to toss this idea around a bit? Cool? If anybody has gotten the chance to do this please post!

REXRICH

[1qckser]

I talked with JE about making some 11.1 pistons, they said no problem, just send them a stock one, only problem is that each piston if im not mistaken is a slightly different wieght due to balancing the whole rotating assembly together, so I would think that if we went with custom pistons some one has to be able to rebalance the whole setup, I know that the SR20DE are balanced like this and when you order pistons and rod bearings you have to give the dealership each number from each piston and bearing, also if the heads are milled then the chain slack would be a huge issue as far as timming, so maybe some custom cam gears could help this out, I think Q45TECH has said that the major bottle neck is after the TB and the intake runners, cant remeber:)

[rsiwicki]

I admire your new way of thinking...but nothing is easy nor cheap on the Q to get extra HP. There are maybe one 1 or two Q owners that would even consider such a modification and one of them being you. We have a prototype SC setup for about $5,000 complete that would add some serious HP that I think others would be more willing to venture vs. getting into the engine internals.

[maxnix]

Milling the heads maybe relatively cheap, but when done on an OHC engine, it truly messes with the valve timing, as the relationship between the crank timing and the valve timing is altered. Very little may be OK, but a little is too much.

How many of those altered engines ran 250K miles?

[Rex Rich]

If the pistons are made to 11.1-1 from the stock spec the they should be applied/applicable in the normal whey. I always rebalanced my engines (10k,rpm/v8) its one of the best improvements that you could do to good machine work in my opinion.

Thanks 1qckser

more replies later...

[sijoko]

I came across a bit of information in regards to the VH45DE.

It seems that the crank from the Nissan Titan engine might fit. The main journal inside diameters (2.7143-2.7144 in.) are the same between the VH45DE and the VK56DE.

I figure that in a year or two, we should start seeing used engines from wrecked Nissan Titans. Then, maybe someone can build a stroker engine for the Q.

I know that there are other considerations, but remember that the VK series shares some of the architecture with the VH series engines.

The only sure way to find out would be to measure both cranks.

Anyway, just throwing out some ideas.

-sijoko

[HeavyDuty]

Wonder if we'd wind up with a 5.0 then.

That'd be very cool, I've had good success with Acura 3.2 TL's/CL's stroked to 3.5 using a homologation between the Odyssey & MDX motors.

Very interesting, lose a little high rpm range, but gains gobs more torque with a stroked VH45..........

[Rex Rich]

I would have to agree with you about nothing being cheap on the Q. I’m sorry I forgot to use the word relative. On the other hand if you are machinist or a friend of a machinist / or mechanic that could help a lot?

How easy it would be is a relative situation too. I think if you were able to R&R the plenum you would be the type that could handle the job of removing, milling and reinstalling the heads? There is another cool benefit that you would receive when pull the heads off, you get to see a couple of the nicest production heads ever made!

If you were to take the car to an everyday shop to have it done it would probably cost up to the equivalent of 5k$ your system? On that note I would expect that only the serous, desperate or the knowledgeable would get in to this fix?

Lets say if you want to do this then do it to an extra engine (do a clay test –valves to pistons clearances) and remove small amount around (0.020) then test. .020 would likely add 20 - 30HP with the 10.2-1 compression ratio this 4.5L has.

There is simplicity here; mechanical as opposed to unsaid other approaches?

Although I haven’t done this to the Q45 - 4.5L I can give enough info as to what the mechanical problems are and what the typical fixes are so the job could be completed and then a write-up could be made for others.

Prototype SC setup! I need to know more please!

Thanks rsiwicki

[Rex Rich]

Good point! I would degree the cams back no matter what.

There is a relatively easy way to do this with the stock sprockets and chain by off-setting the key/keys.

Like I said in another reply I would start with an effective but conservative .020 or maybe .030 milling.

If the job is done write and you take care of your engine as you should it will last as long as they do.

Thanks maxnix

[Rex Rich]

That could be cool.

Hmm… use the rods/pistons too or off set p-pins?How about, swap the engines (easiest kind of) or swap the plenum and fuel system? Think this way; simply put, bigger cams trade torch for HP > bigger cranks trade HP for torch respectively.

Thanks sijoko

[elwesso]

Heres my opinion...

While Im not really savvy on what can/cant be done and other things like that, I think the amount of money put forth do actually do all that crap you could get your supercharger...

Dr Rex Birkmire (sp?) used an eaton rootes type supercharger on a 1992 Q45. It is in the possession of NICO and I believe Greg (AZhitman) is sending it away to be casted and reproduced..... Youd need a custom intake manifold, the SC, pulleys, custom crank pulley, and so on...

Another method we've thought about is the centrifugal type supercharger... Probably more doable IMHO as the amount of custom work is not NEARLY as much... Youd need a centrifugal supercharger, which are pretty pricey (about $1500)... Then youd need to make a bracket, pulleys, piping, and so on....

The latter method is probably better as IMHO not as much custom stuff is needed... And also its much easier to get that stuff done than a full custom intake manifold! All in all, the difference in price is probably near a wash...

Wait, we're talking about HP... We've discussed in detail all the other options, and forced induction is really the way to go... if you want cheap HP, slap on some nitrous and call it good.....

[Rex Rich]

Well… there some more fuel for thought!The list of some what sketchy options grows?

With that said…With a 10.2-1 comp on pump gas this supercharger has got to have some tricky setup situations and even limited use?

It seems to me this engine has a very well matched air to fuel ratio. In this case you would have to do something to get more fuel down in there too?

Nitrous! Yep that’s the way! But… there’s something’s unappealing here… Could it the lack of sophistication?

Eaton Rootes type supercharger! I like to make things so I’d be up for making a manifold. Just imagine… pop the hood with that custom scoop and take another look at that big shiny supercharger sittin in the middle there!

Thanks elwesso

[elwesso]

Theres also the issue of the ECU...

A lot of fuel can be dumped in by altering A/F ratios by the injector open time... JWT has made a boost program for this SC 92 Q, and I would assume they still have it... However, the MAF should be able ot compensate for most of it... OBDII has said to be more flexible in this sort of things.....

So basically, everything is THERE to do it, now its just a matter of putting it together and, as larry the cable guy says it "get er done!"

Remember, this setup has been tested AND used... There has also been the centrifugal type that worked too... Personally i like the way that looks under the hood better... The spider looks so damn good under there, and with the chrome and stuff it would look AWESOME!

[1qckser]

Rex, are thinkn about shaving a few ths off the the head and then notching the piston tops to keep the valve clearence? Also what about just doing a Titan bottom end with the 4.5 heads and intake, I think tech said it would work, cant find a lot of the old post.

[Rex Rich]

Yah! That would look pretty dam good!

So… this centrifugal system is complete except for the induction tubing?And the MAF you think can compensate?10.2-1 is not a problem? Thanks elwesso

[elwesso]

To make it work RIGHT youd wan the JWT ECU, an exta $600 or so, and lots of downtime (order when you start the project)...

But as far as availability, everything is on the market, you just gotta put it together... I think the maf COULD compensate, but if you didnt get a modded ECU I would DEFINITELY run it at full fuel pressure all the time (by pulling the FPR vacuum hose, 43.4psi fuel pressure instead of 34, at idle)... Alos, the KS will retard the timing if detonation should occur... Up to 5 degrees??IIRC? Maybe its more, i cant remember off hand...

We're talking running mild boost, about 6-7 (>10) psi... That has been calculated to give us 400RWHP, so thats crazy HP... The rootes type SC was said to make low end power undriveable... meaning it would just roast hte tires and not go anywhere.. The centrifugal would help down low but really come in as the RPMs are higher and you really get going (and traction is fully established)..

Of course with that youd need the level 10 transmission.....

[elwesso]

Also, after driving the 3800 series V6 N/A and the SC version, which only has about 6psi, the difference it makes its just phenominal.... That boosted 3800 just SCREAMS, and a boosted VH45 would be brutal fast..... Just the SC whine is enough for me (or the BOV on a turbo car)

[Rex Rich]

Um… why not lets take that spin? I always like say; the first one across the intersection wins!!!

How about screw the mill job and go with the supercharger / Titan bottom end with the 4.5 heads and intake!?!?

Thanks 1qckser

[Rex Rich]

This Q-car almost has enough unf at rpm meaning you could easily pile up a stack of tickets pretty fast! Even a body or two using that a lot!

I still gotta say the first guy across the intersection is the winner!?!?

Not only leave those Mustang Monkeys be hind but impressively just disappear with your luxury family vehicle! I gotta stop these friken tires roastin off the car though!

Two flat tires but that super sounds so good!

elwesso

[elwesso]

When I say roasting I mean undriveable.....

They said that with this setup, 3 things would happen (if you gave it any sort of throttle)

1. It would spin and spin out of control (donut)2. You would back off3. It would go sideways and maybe get traction.....

They said ti was nearly undriveable..... Cool? Yes of course, but for maximum performance, probably not.....

Im sure the centrifgual setup will "roast" as much as you need!!

[szh]

While Im not really savvy on what can/cant be done and other things like that, I think the amount of money put forth do actually do all that crap you could get your supercharger...

Agreed! A supercharger or turbocharger is probably the best way to boost horsepower in this particular case. Way less change to the basic characteristics of the engine. Although a change in TCU and ECU programming is probably also needed to make best use of the increased horsepower.

Z

[HeavyDuty]

Not only leave those Mustang Monkeys be hind but impressively just disappear with your luxury family vehicle!

Yeah, and isn't it great there's NO performance mods for them either? And, they're all the same, all rated at the same horsepower, all slow.

[psychic_mechanic]

Add material to cure valve interference? You my friend have never built an engine.

[HeavyDuty]

You beat me to it, Psychic, but I thought I'd let it fly.

[Rex Rich]

Its Friday after a hard week of work in the sun and I’m too tired argue. Besides that I’m just making conversation and collecting info for later use. I appreciate this forum too much to screw with the practical participants that way.As I said we had lots of engines of all different types to try anything we thought would improve the performance. That said… it’s just a simple miss understanding! There is a reason to add material. When our Flowbench essentially said that with the higher CFM gains the head would have a better burn pattern if the combustion chamber had more material in a certain area (different shape) then we would add it. If for no good reason just to see whether it made a difference or what? In doing so the comp ratio was now higher and so less surface material needed to be removed and so on... I don’t know for sure… but you must not have been there because I am sure you would have remembered doing this? Oh wait… there was a guy that got hit in the head by a flying p- rod from a dino gone bad?

Sorry guys but I don’t type that fast so I don’t want to have to post to impress all.

Lets get back to the good ideas.

Thanks psychic_mechanic!

[PoorManQ45]

here is a link that will tell you how much it costs to prepare a VH45DE for boost.

http://www.automotiveforums.co...20125

[Rex Rich]

Yah I aren’t going to spend that kinda $ until I can see an end to it all. I’m glad I don’t see an end solution yet cuz I know it’s big $ anyway. Although the HP they’re talking about sounds like a good amount for the $ to me.

Like I was talking about before, it sucks that I don’t have the engine building shop anymore cuz I could easily start testing the components now and come up with something for everyone that wants to make big, drivable and reliable HORSEPOWER!!!

Maybe I will name the next post; 50 more horsepower!!!? although not big HP see how close we get to bolt-on and drive, because you could probably get 50hp from just a mill job and a little more fuel?

Thanks PoorManQ45… let us know what all of your wild ideas add up to bud?

[PoorManQ45]

If you have pistons custom made for two engines of similar size, Lets say 4.5 vs 5.0. Shouldn't they cost about the same? I mean, the manufacturer doesn't care what the pistons are going into, right. You just tell them what you want, and they make it. It should be the same way for the crank, and rods, right?

So, I don't understand why it costs so much to build up a VH45DE engine. Could someone explain this to me?

I'll keep you informed on my works of art .

[Rex Rich]

Well I think I know you mean. It would depend if you were dealing with the same manufacture for quotes. Also it depends on the popularity of the engine you are working with meaning its essentially less work to design same part for a 305/350 Chevy than for 4.5 Infinity engine for instance.

When I was building engines for a few reasons I would automatically double the labor charge for a similar diesel engine over a petrol engine even though to me there about the same amount of work.

PoorManQ45

[IvoryJ30t]

So, I don't understand why it costs so much to build up a VH45DE engine. Could someone explain this to me?

because everything has to be custom.

crower custom rods- $1500crower custom crankshaft- $2000 [+/-]ross custom pistons- $1500cometic custom MLS headgaskets- $400arp rod and head bolts- $??swaintech ceramic coating on piston tops, heads, and exhaust ports, swaintech moly coating on piston skirts and bearing shells- $1500 [+/-]block and heads hottank, cylinder hone- $??new oil seals, valve seals, valve guides- $400 [+/-]high precision micrometer set [0.00005 inch accuracy] - $1500log exhaust manifolds w/ T3 flanges- $400twin garrett GT turbos- $2400tial wastegates and bov- $500FMIC- $600trip to mandrel bender for IC and exhaust- $1000fuel system redesign [pump, lines, rails, regulator] $1200custom radiator- $??engine management, autronic or motec - $3000-5000custom transmission adapter [Z32 trans] and twin plate clutch- $1800custom driveshaft- $350clutch LSD- $900

im sure theres at least 10 things i forgot off the top of my head.

thats what it takes to do it CORRECTLY.

then again who cares about reliability. i guess having to wonder if the motor is going to grenade everytime you see positive manifold pressure is excitement in itself.
Modified by IvoryJ30t at 9:09 PM 9/19/2004