my 200mph rx7 build

[turbotoaster]

seems my turbo has to possibly go back to an older idea.
 
speaking to manny at masterpower today about the mp4505...basically a gt42 sized turbo.
 
they claim 750-1000bhp for that turbo and the compressor and turbine areas are actually slightly larger than the gt4202 so thought all was good as he will sell me one with a t4 1.22 a/r for $700.
 
I enquired about running 2bar and seeing if this is within its specs, ie will it just generate more heat so he sent me a compressor map for the turbo.
 
to say its not really promising is an understatement
 
here it is so you can see it
http://www.glowfoto.com/static_image/16-114107L/6259/png/04/2010/img5/glowfoto
 
it is in kg/secs instead of lbs/min to convert it, multiply by 2.2, then multipy by 60
 
so 0.5kg/s is 66lbs/min
but running 2bar of boost is 0.58kg/s which is only 76.56lbs, or about 760bhp piston, or 588bhp rotary....ie not enough power, im surprised really as they are very big wheels on the turbo!
 
Ive emailed him back to confirm whether im correct or not but i have a feeling that im right, if so then its back to the borgwarner or maybe if a cheap gt4202 if one pops up

[shaunwil]

How much difference is the T6 variation ? Maybe not enough flow in the t4 , possibly ??

Shaun

[turbotoaster]

They dont do a T6 version shaun, else id look at that, seems if i want to stay t4 so i can save money on the manifold ive either gotta have a gt4202 or a bw s475 with a t4 1.25 rear end, the bw is cheaper but not as cheap as the masterpower was gonna be....shame

oh yeh

got myself a decat pipe for my birthday this year, even with the big turbo ill be running a 3inch exhaust on the road as due to running low boost there wont be massive back pressure issues and it keeps the noise down to semi-sensible levels........to say its loud compared to when it had a CAT on it is a bit of an understatement!!
When i started it up i crapped my pants, thought the decat had fell off, my neighbours werent to impressed!

Though its much better from 7-8krpm now as the ports where being heavily restricted by the CAT.

Big difference in weight


new gaskets and bolts which is nice


checked flanges and they are both true and flat


had to jack the decat up so i could get the lower brace back on, but all bolted up!!



video of starting it up

http://www.youtube.com/watch?v=0oiKRYFv2I8

[shaunwil]

I had one of those in the past (still have it knocking around) and it made some good figures on a small turbo. With a knackered back box I was seeing 112db at 3/4 revs :Giggle

Its a shame your budget isn\'t bigger and the pound was still strong against the dollar or I would suggest the GT42r A-spec makes with a Tial setup. Really nice but expensive !

http://www.rx7club.com/showpost.php?p=7715400&postcount=64

Shaun

[turbotoaster]

yeh it would be nice to have something like that, literally plug and play but i just dont have the money for something like that, i can dream though.
 
Decatted is proper loud though, its a well weird idle aswell, havent heard any other rotary sound like it before

[Dmentia]

Yeah, when you came round I thought something was wrong! Very loud and a little tractorish. Thought you\'d thrown a tip! Definitely goes better!

[turbotoaster]

yeh, its a weird sound, but doesnt seem to have lost any power and only started making this noise since i put the decat on, wont throw a tip sitting at idle for 5seconds lol

Does seem to calm down alot when you pull fuel out of the idle and the engine is warm, here it is warmed up

http://www.youtube.com/watch?v=pzRRHov_KUY

[Grant Monkhouse]

You should here my car idle especially in the cold weather; sounds like a bridge port. But is really smothe and quiet now the weather is better and with the bit extra work on my map that carl has done.

What back box have you got on your car? I have a tiger back box on mine so the noise is quiet, but when I give it some poke through first secon and third it sounds like a big motorbike, and with the lightened flywheel it picks up that little bit quicker.

With the Decatur you will have to add a bit more fuel at high rpm on boost, will you not as with a decat they run a little lean?

[turbotoaster]

You should here my car idle especially in the cold weather; sounds like a bridge port. But is really smothe and quiet now the weather is better and with the bit extra work on my map that carl has done.
 
What back box have you got on your car? I have a tiger back box on mine so the noise is quiet, but when I give it some poke through first secon and third it sounds like a big motorbike, and with the lightened flywheel it picks up that little bit quicker.
 
With the Decatur you will have to add a bit more fuel at high rpm on boost, will you not as with a decat they run a little lean?

Its a trust exhaust that came on it from japan, im not sure how it compares to other exhausts but its not quiet at all.
 
When i had it on the dyno with a cat on the leanest it hit was 11.1 afr so checking the knock values at high rpm its really low, i know that cant replace a proper afr or egt gauge hence ill be purchasing one next month, im gonna go with innovative motorsports one i think
 
DB-Red Gauge / LC-1 Kit which is only $229 but people have been saying its a very good kit for the money, ill put the bung in the downpipe so that it stays consistant just incase the flange on the decat leaks, i doubt it would effect anything because of the positive pressure in the exhaust but better safe than never

[Ed_RX7]

get an aem one you wont regret it!!!!

[turbotoaster]

ive heard a few bad things about them, that there latency isnt on par with others and there software isnt all that great.

But then i have heard a few people say they had problems setting up there innovate so seems swings and roundabouts at the moment

[Ed_RX7]

ok....ive had mine on a dyno and its was on par with the one at the dyno!....as for software...its tells me the afr thats it ...dont need it for anything else...so im chuffed with mine.....good luck with the innovate one though.

[turbotoaster]

well ill be honest and say i havent made my mind up yet, im not a fanboy of any of them to be fair and ill go with the best one for my money.

where was it tested against...ie whos dyno, i know dyno ones are good, just want to compare and contrast and if theres a few people who recommend the aem one then i would be happy to put my money there

[turbotoaster]

Watched the formula 1 today and even though it was 530pm the sun was still out so decided to fit my new radiator.

Heat is a major factor on a rotary engine so getting the temps down makes a big difference. As you can imagine, running flat out for around 32secs with 700bhp will put alot of heat into the system, hopefully this should keep it in check.

Ive gone from the standard 35mm thick one to a 52mm ali rad, its an ebay one but has been proven to cope much better when the engine is pushed, gavinruns one that was getting 120c temps on a stock rad on trackdays, changed to this and hasnt been above 106c

Had a quick look at my online workshop guide on how to remove the rad, better to know what your doing before you come to do it.

After looking at the picture, it says i have to remove the undertray and the anti-roll bar.....bugger that i thought, ill try from the top!

removed intercooler

removed fans.....they are awesome from factory so will keep them


removed radiator, actually just pulled out from the top, dead easy, not sure why it says from the bottom!

Big Space!


Came to put the top rad hose back on and because the outlet didnt stick out as much as the stock one i couldnt get it on with my spring clamps, so cut a little bit of the plastic away, you cant see it at all so made no difference to me

Again, bottom part didnt line up as you can see

All in and sorted, the angle it sits is not as horizontal, the reason for that is because it hits the chassis when you try to go to the point where the original rad sat, you can get around this by fitting the rad from underneath but i couldnt be bothered for the case of 1-2* more angle



Its been a bit of a pain and not an oem fitment, but to be honest i didnt expect it to be, only seen people run this rad upright in the past so wasnt 100% sure what to expect, but for £100 compared to £300 for a branded one im happy to mess about fitting it as my time is free.

Just going to duct off the sides of the rad now so all the air hits the rad first

[turbotoaster]

Little update, wideband arrived in the post today.

Got it from a company named txautoplex on ebay from as you guessed it,  Texas.

Ill have to admit, im always very unsure about buying from abroad, would  be very easy for the company to rip you off as you cant go visit them.

But true to the guys word it was shipped out as soon as i paid and gave a  tracking number so i could keep an eye on it.

He included free shipping so it only cost me £145 brand new in total and  also put on the shipping docs a really low value so i didnt have to pay  taxes....didnt ask him to do that so awesome!!

Id recommend buying from him as hes £30 cheaper than anyone else and  gives great customer service

some random pics, ill do a full installation next week when i get warren  to help me with wiring!

Gauge, was expecting it to have more depth than that which is a bonus

Bosch Lambda sensor


once i get it in ill start doing some proper tuning as my engine could  really do with sorting out