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-   -   My projects progress! 9 Months *story+photos* (https://www.rx7club.com/1st-generation-specific-1979-1985-18/my-projects-progress-9-months-%2Astory-photos%2A-415820/)

teddyrx2 08-17-07 12:28 AM

looks really nice bro

dj55b 08-17-07 12:46 AM

275hp? What am I missing here ... By the sound of it, it seemed like they were pulling it in 3rd gear? Whats the reason for that? If I'm wrong what is the actual HP output of the car? Any chance you have something of before the ITB's too for comparison's sake? It seems to have added a nice fair bit of torque by seeing how much your hood shakes in that run.

H4Inf 08-17-07 02:26 AM


Originally Posted by dj55b (Post 7244650)
275hp? What am I missing here ... By the sound of it, it seemed like they were pulling it in 3rd gear? Whats the reason for that? If I'm wrong what is the actual HP output of the car? Any chance you have something of before the ITB's too for comparison's sake? It seems to have added a nice fair bit of torque by seeing how much your hood shakes in that run.

haha i wish it was 275hp.. its 120.. maybe i shoudl have said that aye........ the dyno has 2 ranges. 0-150 and 150-300... we are running on the lower range. engine is brand new so it still has to bed in before thrashing the crap out of it.. N/A Extend Port. :)

This is a brand new engine, first run on mega, so no comparisons really... the old 6port engine with no porting, no aux sleeves pulled 100hp at 7000rpm... that was the most it made lol.. after pulling that motor down we found it was really stuffed :) amazing it still worked haha.

anyway once i put 1000k on the clock we will retune it up to 9k rpm and then see how much power it makes.. maybe around 160 i hope!!! also running a touch on the rich side right now just for safetys sake.. she is going well :)

dj55b 08-17-07 10:55 AM

I think you should aim for more than 160 if thats the case. My 12a with my holley that was running a tad rich and poor stock ignition made a little over 147 at the wheels, I'm expecting with good tuning of my ITB's and the second gen ignition system that I would be closer to 160.

H4Inf 08-17-07 08:12 PM

Yeah... i guess the other thing is that different dyno's read differently. This is a mega old dyno in case you hadn't noticed :) Everyone who uses it says it under reads a fair bit... main thing is that its safer than tuning on the street :) just got to bed the engine in, then retune up to 9k.. should read over 150/160 on this dyno i hope :) either way it feels so much better than my old engine which was a 6port running no aux sleeves.. and that only pulled 100hp on this dyno..

i have to modify the front suspension, as since the brake upgrade the wheels stik out a little more, and when i go over bumps, are hitting the guards and hurting them... deforming the right one...!!!

dj55b 08-18-07 01:59 AM

Ya i guess I could of clued in on that too ... you should get it done at another dyno and see what it comes up as there.

As for the tires hitting the guard, why don't you just roll the fenders? That should be more than enough.

H4Inf 09-15-07 09:49 AM

Update.... has been a while :)

- Had harder shocks put in
- Upgraded the headlights to 100watt low beam :) with brand new h4 lenses, completely rewired with relays!! hooray at last!
- Bent my bonnet arm a little so it no longer can fall out!!
- Swapped rear springs from stock to some pedders standard height but stiffer ones
- Oil change and filter... after i put 1000k on the engine :)
- Some more dyno tuning
- Added an air temperature sender to megasquirt- has helped smooth some problems out
- Had some new oil hoses made up at Pirtek... good for 500psi :) Beasts
- Had my front right guard rolled so prevent damage from tyre hitting it :)
- My new front shocks completely failed and pissed out their fluid... got those replaced under warranty!
- Modified the tune a little because adding air temp sender caused about 25% enrichment (its part of the base fuel calculations)

So that's whats been happening :)

In other news, the EPA are at me again for vehicle noise... so next weekend we're gonna be looking at that... and install the new oil hoses, perhaps a little tune.

Coming up shortly I will be building a little addition on the MegaSquirt so i can run the stock Crank Angle Sensor and FC leading and trailing coilpacks... Next 2 weeks :)

In the mean time it's great fun to drive!! Wooo :)

dj55b 09-15-07 11:10 AM

Can you post pics where you mounted your Air temperature sensor? I'm not too sure where to mount mine on the ITB's and if the sensor needs to be covered or what.

Whats the new HP numbers if they have increased from last time too. Dyno graph to show the smoothness of the curves would also be great.

Sam

H4Inf 09-15-07 10:06 PM

I've just cable tied my temp sensor to the fuel rail so that it sticks up right next to the air filter. I need to pick up a plug to replace those spade connectors :) So long as the sensor is mounted in a position that will pickup the temperature of the air that the engine is getting, you should be fine. I don't think the sensor needs to be covered... perhaps a good location would be after the air filter, as this would practically guarantee the sensor would not get wet- not that water would kill it, but it could give a false reading.

http://stuff.pw.cx/CIMG2105%20(Custom).JPG

This dyno doesn't do graphs :) It's completely analogue and runs on water LOL... one wheel spins shooting streams of water at a finned wheel attached to the rollers the car sits on... to increase the load, the wheels move closer together :).

I didn't see how much power it made, the exhaust fumes were so bad I left the garage.. Should be back on the dyno in 1 week, so I'll post an update then.

Just yesterday after modding the tune, I was surprised to find I could break traction in 2nd gear in the dry- not from a slammed gear shift, but just by pushing my foot too far :)

REVHED 09-16-07 08:00 AM

Sorry but having the air temp sensor sticking in the air like that is dodgy. It can't be that hard to tap it into the manifold. ;)

H4Inf 09-16-07 08:03 AM


Originally Posted by REVHED (Post 7338215)
Sorry but having the air temp sensor sticking in the air like that is dodgy. It can't be that hard to tap it into the manifold. ;)

It's the same air that goes in lol.. not the neatest solution. I'll sort someting more permanent out later, although really theres not many places to mount it.. no real airbox as such.. trumpets and butterflies right under the filter, then straight down into the engine.

dj55b 09-16-07 12:35 PM

The one thing about placing it inside the manifold is that because its after ther fuel injectors, would the fuel spray cool down the intake temps by a few degrees? I'm not 100% sure what the IAT exactly does yet, maybe just some very minor adjustments at idle and what not, but thats about it.

H4Inf 09-16-07 07:17 PM


Originally Posted by dj55b (Post 7338654)
The one thing about placing it inside the manifold is that because its after ther fuel injectors, would the fuel spray cool down the intake temps by a few degrees? I'm not 100% sure what the IAT exactly does yet, maybe just some very minor adjustments at idle and what not, but thats about it.

Is it often placed after the injectors??? That sounds a bit odd to me.. you may be right though.

IAT sensor is used to calculate the density of the air. If it is cold, the air density is higher, thus you want to richen the mixture a little... vice versa if it's hot, air density is lower, so you would want to lean the mix a bit.

For example I found that from 16C to 79C there was a 25% difference in the enrichment. These are not 'real' values, but without my IAT plugged in, the ecu assumed 79C degrees for some reason, then when i connected one up, my fuel map was enriched about 25% overall :P quite a lot! ive since recalibrated it a little myself.

From the megasquirt site... The ideal gas law:

PV = nRT

P = pressure,
V = volume,
n = number of moles (which is related to the mass of the gas, i.e. 1 mol = 6.023x1023 molecules of the gas, and n = mass (in grams)/molar mass(MM)),
R = the ideal gas constant,
and T = the absolute temperature.

THUS

P = VE * MAP (i.e. the pressure in the cylinder in kPa),
V = CYL_DISP = the displacement of one cylinder (in liters),
R = 8.3143510 J/mol K,
and T = (IAT-32)* 5/9 + 273 to convert IAT from ºFahrenheit to Kelvin.
This is how megasquirt calculates fuel required. Other ECU's may or may not be similar, but i'm sure the IAT is used to provide minor enrichment only, however it would be more noticable testing it in summer, then winter.

dj55b 09-16-07 10:37 PM

I guess that I could of guessed air density which makes sense. Good thing that I have one.

Naegleria_Fowleri 09-17-07 03:23 AM

Your car looks amazing. I'm glad to see you are still into your car after all this time, as well.

H4Inf 09-17-07 06:05 AM


Originally Posted by Normality_Glitch (Post 7340952)
Your car looks amazing. I'm glad to see you are still into your car after all this time, as well.

Thanks.... I probably should save my money for a house though... lol... Regardless of a house, I plan on keeping the car forever and maintain it at least :) I see a lot of people selling cars in order to help them buy a house.. I don't want to do that as its the fastest way to lose all value of my investment.......

Oh well.. moving forward :) My next major task is to build a little add on circuit to the megasquirt to take the standard crank angle sensor signal... got to piece together a lot of info..... aghhh

pjr 09-17-07 08:34 AM

So... what's your plan for the exhaust? Are the EPA complaints related to the sound or to emissions?

H4Inf 09-17-07 08:59 AM


Originally Posted by pjr (Post 7341204)
So... what's your plan for the exhaust? Are the EPA complaints related to the sound or to emissions?

Thankfully the EPA is just noise... the police reported me (last time as well)..

Current exhaust is like this:
http://stuff.pw.cx/current_exhaust12092007.jpg

The current plan is to switch the resonator just before the axle with a catalytic converter. When they do the noise test they also verify that adequate emissions equipment is in place. Supposedly this should bring down the noise level, but I am not 100% confident in this.

I suspect we may have to open up the muffler and modify it so it is less of a straight through nature. The EPA do not support any sort of temporary restrictor plates, so it has to be done right. I also agree that the car is too loud, so it's an issue I wish to address properly and for the long term.

Since getting this notice I have felt a lot better about driving because i'm basically immune from getting reported for being too loud, because ive already been reported :) But once i clear this, i would like to be able to drive around without having to worry about disturbing the neighbours, police and EPA.

Since getting the 7 back the low frequency response in my ears has again been reduced, as expected... hehe.

As a backup, I have been looking at Rotaflow products. Jon from rotaflow said with the use of one of their resonators and the RFS250 muffler, I should get about 94dBA on the noise test. These are a well known brand for rotaries and well tested. With a test done with this muffler on a dynorun, their test car made 130rwkw with no exhaust, and 129rwkw with their rotaflow muffler. The mufflers are quite expensive though, so if I can I'd like to be able to come up with a solution myself :)

FYI This is how the test is conducted. They mount a sound sensor 50cm from the exhaust outlet, at a 45 degree angle to it, at the same height of the exhaust. They then hold revs at 4500rpm (for any rotary engine) and let it drop to idle and watch the dBA rating. They repeat this test 3 times to confirm the reading. Cars made before November 1982 can be up to 96 Decibels(A).. cars made after than can be up to 90 dBA. Every 3 dBA is double the intensity :)

gsl-se addict 09-17-07 09:15 AM

Paul,

Would you like a new plug for your IAT so you don't have to use the spade connectors? I can send one to you with some pigtails attached. Free of charge, of course. On the IAT, it would at least look better if you could find a spot to drill and tap. Probably won't make any difference to the performance/operation of the FI system, though. It should go before the injectors. Maybe the filter housing would be the easiest spot for it.

Kent

Naegleria_Fowleri 09-17-07 11:24 AM


Originally Posted by H4Inf (Post 7341018)
Thanks.... I probably should save my money for a house though... lol... Regardless of a house, I plan on keeping the car forever and maintain it at least :) I see a lot of people selling cars in order to help them buy a house.. I don't want to do that as its the fastest way to lose all value of my investment.......

Oh well.. moving forward :) My next major task is to build a little add on circuit to the megasquirt to take the standard crank angle sensor signal... got to piece together a lot of info..... aghhh

I am currently buying a house. Not only am I buying a house, I bought another Rx7, and a daily driver. I now own three cars. lmao. Its possible to do it all.

H4Inf 09-18-07 06:53 PM

Hey Kent, what a generous offer! I agree it would look better... I think there might be a small gap in the base of the trumpet casting where I could put the temp sender... Will look at it on Saturday. If youve got a spare connector I'd love to install it in my car :) Thanks!!! :D

Normality_Glitch... Nice to hear you can do a house and 3 cars at once :) Good work! I will try to do the same... for my third car i will need an rx8 though :P

gsl-se addict 09-18-07 08:39 PM

Paul,

I'll dig one up and throw it in the mail for you. Just pm me your address if it has changed from last time. Car is looking good. Nice work.

Kent

H4Inf 09-22-07 07:49 AM

Thanks Kent!!!

What a long day it has been :)
- oil lines installed
- played with a porsche carerra gt running on megasquirt
- went for a ride in a turbo 13b first gen
- checked out an amazing morris 1000 running 13b supercharged on LPG!!!!!!
- made my exhaust quiet

First up Stuie put in the new oil hoses i had picked up from Pirtek - good for 500psi :) They look nice and neat, I just need to put a bit of conduit around a small area that may rub on the engine mount at times.

Secondly we attacked the exhaust sound problem.
Attempt #1 - Install CAT - Made it a little quieter but not quiet enough
Attempt #2 - Install a diffuser into the exhaust inlet of the muffler (bent piece of tubing) - Again dropped the noise but not enough.. getting about 96-99 dBA
Attempt #3 - Weld one of the exhaust tips closed. SOLVED

Unfortunately this has taken me from 135rwhp to 85rwhp lol... ouch... anyway I am going to go for the noise test and over the next few weeks we're going to do some research into doing a custom build of a muffler which will be ok for power but also not too bad on noise :) Driving home I couldnt even hear if the car had stalled or was still running lol. Will easily pass the test....

Also finally got an ok photo of the car with these wheels on it lol...
http://stuff.pw.cx/car_side_sept07.jpg

dj55b 09-22-07 03:11 PM

Thats a huge horsepower drop there, don't want to choke your rotary too much

H4Inf 11-24-07 05:50 AM

yeah choking is BADDDDD!!!!!

Ah lots has happened since this... I have had the exhaust modded some more to unchoke it :) Maybe this can be a pictorial progress... here goes..

Twin rotaflow mufflers :)
http://stuff.pw.cx/CIMG2625%20(Large).JPG

KYB shocks installed in place of the failed (2nd time) pedders comfort gas shocks.

Made up a shroud so i could add a second thermo fan, as the other day the heat was WAY high and bad!!! unshrouded single thermo was not enough!

http://stuff.pw.cx/CIMG3245%20(Custom).JPG
http://stuff.pw.cx/CIMG3261%20(Custom).JPG
http://stuff.pw.cx/thermocooling.png

Next up I'm switching back to long primaries in the exhaust, as this apparently will help my top end power... AND i will be doing a cold air intake.. which means ill be getting some ram-tubes and making up a box!!! :) When i do get those put back in ill have an o2 sensor bung put in too.. I have a wideband kit too which will tie into megasquirt (Wiring already done! :)) so this will help HEAPS with tuning and give a whole nother dimention to the datalogging!

Currently the worst intake air temp I have seen is 48C or 119F and this was sitting in my drive and just after the thermo fans came on lol..

So that's some updates :) Stay tuned....

OH.. PS.
My oil lines failed.... I was flying up a hill at high rpm and one of the hoses popped off the barb fitting and sprayed oil all over the road!!! Bad :P Anyway i noticed pretty much instantly and everything is fine :D SO LUCKY! This time i made my own hoses, to perfect length and to my standards :)
http://stuff.pw.cx/CIMG2765%20(Large).JPG


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