VH45DET - 446wHP - 93 octane - 6psi

[Jeff Taylor]

Welp, just dyno'd the car tonight.

The stock 370cc injectors are at 100% duty cycle and the MAF is railed at 5.0V with only 5 - 6 psi of boost on 93 octane. Needless to say, the upcomming MAP system with larger injectors are long overdue.

The tach signal for the dyno was a little screwed up, so my displayed engine rpm and torque curve aren't accurate. However the measured power is.

Here's the graphs:





...not bad for 6psi

Jeff

[gammer_ghn]

Holy crap 635 TQ wooooooow with my stocker 4.1 i cant realky get passed the stopsign without churping at 2k rpm i guess your doing standstill all day errday haha nice one!!!

[SuperHatch]

The tach signal for the dyno was a little screwed up, so my displayed engine rpm and torque curve aren't accurate. However the measured power is.

Holy crap 635 TQ wooooooow with my stocker 4.1 i cant realky get passed the stopsign without churping at 2k rpm i guess your doing standstill all day errday haha nice one!!!

It looks to me like it's really making about 430lb-ft at peak.

[Carl H]

time for a z32 maf or a dual maf setup...

[Carl H]

very nice numbers...when did the injectors max, do you have an exact rpm/airflow?

[Jeff Taylor]

Holy crap 635 TQ wooooooow with my stocker 4.1 i cant realky get passed the stopsign without churping at 2k rpm i guess your doing standstill all day errday haha nice one!!!

The car currently has stock 195mm rear tires on it...lol Anything after 4500rpm in 1st, 2nd, 3rd, and sometimes 4th puts the car sideways.

[Jeff Taylor]

very nice numbers...when did the injectors max, do you have an exact rpm/airflow?

I'll post a Consult datalog of the pulls soon.

[elwesso]

WE NEED A VIDEO!!!

Why does the torque chart look so torquey??? The curve is definitely a lot more linear than a stock VH, but looks nice...

About what RPM were you hitting that plateu, all im seeing is the MPH?

It looks to me like it's really making about 430lb-ft at peak.

agreed.

[Jeff Taylor]

WE NEED A VIDEO!!!

Video: http://filebox.vt.edu/users/je...i.wmv

I'll have a dyno plot with rpm as the base soon.

[ScottJackson]

VW guys have done well with making a larger MAF housing and then simply putting in larger injectors. I was thinking of doing this with my BMW. It has 18lb injectors stock and something like a 3.1" ID MAF. I could toss in 36lb injectors and then to compensate just make a 4.5" ID MAF. The idea is to double the flow of the injector at the same pulse duration and then double the cross sectional area of the MAF so it reads only half the air going through the meter. So the computer thinks there's half as much air going into the engine so it shortens the injector pulse by half. However, since the injectors are double stock flow, the same amount of fuel as before is injected. It should give you a lot more head room before pegging the MAF.

[sijoko]

Very nice! Are you still running the 1.08 housing on the TV7512? At what rpm does the boost show up?

[gs14racer]

I am so green with envy...

[Florida240sx]

Thank you... as I look at the turbo in my closet...

[Jeff Taylor]

Very nice! Are you still running the 1.08 housing on the TV7512? At what rpm does the boost show up?

Yeah. I'd say it was at 6psi by 4500rpm.

[Mettler]

Great work Jeff, you're not far from maxing out that fuel pump too!

Very interested in seeing how far the engine can be pushed with 10.2:1

Do some burnouts for us

[darinz]

What is it reving to? I got 375rwhp with 370cc injectors etc and 10psi but that was at 6000rpm where the injectors hit 87%. I'm not switching cams either so have yet to tune it for top end, so it would be good to see what you arre getting as a guide. With my T04z 1.15ar, I'm getting boost at 2000rpm and have hit 10psi at 3000 which it holds through to 6000 where the rev limiter is currently set due to injectors.How does the turbo you have compare to my garrett turbo?I'm thinking about dropping boost to 6 to 8psi so that I can run pump gas as avgas is a pain in the arse to carry around.The biggest difference is that mine 375 was with 33x12.5/15 mud tyres, so it would be quite a bit more if on a car tyre.

[Jeff Taylor]

Very cool.

In that pull the engine was revved out to 7000 rpm...I'm still taking it easy on the motor.

I'm not sure what the size differences in our turbos would be. My compressor wheel inducer is roughly 72mm, the turbine housing is a 1.08 A/R T6.

[qsiguy]

In light of these numbers I think I will need to set stage 2 at 6 psi instead of 8 until I'm ready to make the jump to larger injectors and MAF.

That has to be exciting for you getting on the road. Congrats! I love the way you mounted and configured the turbo. More pics and video!

[darinz]

The good thing about a 6k rev limit is I can sit on the rev limiter spinning the tyres virtually all day without worrying! With how much useable power I have I won't be hurrying into more. It is very driveable as there is a bit of lag that gets you moving before the power starts bilding. Once it hits anything over 3k then you need to be in a straight line!I'm doing some high speed testing etc on the beach this weekend so will see how it handles at high speed.

I've just found out about a comp I want to do that will require me to basically be running pump gas so I'll be really keen to follow what you do as a guide for changing mine around a bit. I'm thinking about a 6psi spring and let the EBC control what we boost to depending on fuel. Then I can just change maps depending on wether I am running avags or pump gas.

[Jeff Taylor]

In light of these numbers I think I will need to set stage 2 at 6 psi instead of 8 until I'm ready to make the jump to larger injectors and MAF.

That has to be exciting for you getting on the road. Congrats! I love the way you mounted and configured the turbo. More pics and video!

Yeah, I didn't expect to max out the injectors until around 10psi, but this engine/turbo combination seems to be more efficient than I thought. I suppose I could increase the fuel pressure or lean out the top-end slightly, but for now it seems very reliable on 93 octane.

I'll have to find a 'controlled test environment' for an acceleration video in the next few days...

[Mettler]

Watch out for those controlled test environments, I hear they can damage your numberplates if you don't remove them first :p

[T45]

Damn Jeff, you should post up the vid of the stock KA dyno. Unbelievable. If you hit that much with the KA I can't wait to see what the VH does on stock internals.

[qsiguy]

Jeff, what tune are you using for your ECU? Have you retuned it for the boost? I know you had a good tune for NA but curious if you've done anything yet or just using the original tune still. Using 8 bit or 16 bit ECU?

Hoping to pick yer brain..... and maybe beg steal or borrow a copy of the map if you've made a decent one for 6 psi....

Oh, and are you monitoring the a/f ratios? If so, how's it looking with the tune you're using?

[Jeff Taylor]

Damn Jeff, you should post up the vid of the stock KA dyno. Unbelievable. If you hit that much with the KA I can't wait to see what the VH does on stock internals.

Thanks. The original goal of the VH project was to push the engine to its stock mechanical limits like the KA, which I may still do.

Here's the KA dyno video:

http://filebox.vt.edu/users/je...d.wmv

[Jeff Taylor]

Jeff, what tune are you using for your ECU? Have you retuned it for the boost? I know you had a good tune for NA but curious if you've done anything yet or just using the original tune still. Using 8 bit or 16 bit ECU?

Hoping to pick yer brain..... and maybe beg steal or borrow a copy of the map if you've made a decent one for 6 psi....

Oh, and are you monitoring the a/f ratios? If so, how's it looking with the tune you're using?

I've been tuning the stock 8-bit ECU for boost using the stock injectors and MAF in a blow-through setup. The AFR's in the top-end are a steady 11.8:1.

The tune I have now is actually not very far off from the NA tune in the low-end, however I made fuel changes above the boost threshold and slight ignition timing retard around peak torque. With further tuning, I should be able to produce another 15 - 20 hp at the same boost level. There is currently no detonation on 93 octane at 6psi boost, however since my fuel injectors & MAF are currently maxed out, I have to be very careful of the weather conditions I'm driving in & boost pressure.

Jeff
Modified by Jeff Taylor at 11:51 AM 12/6/2007

[qsiguy]

Here's the KA dyno video:

http://filebox.vt.edu/users/je...d.wmv

Holy cow, 30psi on a stock internals!

[valkyie]

Hi, I am new to this forum. I am searching for a method to apply boost to my engine. I have a 300ZX NA with J30 engine installed. I plan on making a supercharger for my engine powered by the belts hopping to run 6 PSI and I would like to ask you some questions.

I see at the bottom of your page in your signature you state that you ran stock internals on you engine for a boost of 6 PSI and gained some big ponies. How did that work out for you?

Did you have any problems in engine reliability?

How should I determine how much boost I should run on my J30 engine?

What size fuel injector would you recommend that I upgrade to for the 6 PSI? And any other question I should have asked. Thanks

[Jeff Taylor]

I'd recommend purchasing some books on turbocharging or supercharging, to learn some of the theory behind a correct engine setup. Different turbochargers and superchargers perform differently. The best way to determine how a blower will perform is to get a copy of its compressor map and do some calculations using your engine specifications.

If you plan on running a low boost setup, it may be most cost-effective for you to just upgrade to 300zx-tt injectors, which are 370cc/min, and should be good for 330 wHP or so.

In determining how much boost to run, you should consider how power your engine can handle, if properly tuned. With good tuning, that engine will probably be fine making 300 - 400 hp in its stock form. It's difficult to create a rule-of-thumb about how much boost is too much for a particular engine, because of varying efficiencies of different turbos. 6psi on my 72mm turbo makes 446 wHP, but it would probably take 10psi on a 60mm turbo and 18psi on a 50-trim T04e to make the same power.

Good luck with your project!

[valkyie]

Jeff Taylor, Thank you for the feedback. Yes I have my supercharging book on the way. Like I said I plan to make a supercharger powered by the belts. Also the fuel injectors with ECU will be upgrade as well. I guess its time for me to hit the books. Thanks
Modified by valkyie at 9:30 PM 6/18/2008

[valkyie]

JT, Just wondering what size injectors would you recommend for running the 6 PSI boost. Also I see these boost control kit and I know I will need it and a blow off valve. I understand how the blow off works but I am not sure how the boost control works. Can you please explain this parts function.