Some may find this interesting, some wont. here's my hack job turbo/m90 setup

fasterthanyou

Registered User
I'm only about 8 years late to my own thread from where I wanted to do a turbo/m90 setup.

Aside from needing to make an actual pipe from the blower outlet to the return plenum this setup is ready to hit the road.

Who knows, maybe in another 8 years Ill actually hit the track with this setup.

I went to my local track a few months ago with the turbo setup. Best this car has gone on turbo alone was 14.1 at 106mph 2.5 60 foot. 10 psi and 15 degrees of (actual) timing. Maybe the blower will help the 60 foot. Maybe not... yep.


https://youtu.be/6vLT_kHJe2M
 
No intercooler just water/meth. The silicon coupler from the outlet to the return plenum will be stainless pipe. I have one tack welded together from a dozen or so pie cuts.. I need to finish the welds.

Wastegate is referenced off of the compressor housing so it will be targeting 10psi. The m90 pulley system is stock so that should be around 10psi. Just stabbing the throttle in park netted around 9 psi so I am assuming the m90 boost pressure will be around there within a psi or so.

Whether 10+10 = 20 or not will be found out.

Really my torque converter is too tight to spool the turbo off the line, I had the supercharger laying around so yeah.. that's how this came about.
 
There will be a compounding affect, ie 10+10 will not equal 20 but will probably be much more. Really it depends on the size of the turbo.

I want to do the same thing on my junkyard car and run the turbo at something modest like 5 psi.

You should consider going to E85 or even straight methanol since you have got rid of the intercooler, there is going to be a whole lot of heat.
 
I found this on an SVT site. It came from the internet so it must be legit, at least that's what I'm going to assume.

It's a boost reference chart for the result of turbo psi + supercharger psi.

So with my 10lb wastegate and 10lb pulley system, this should be in the 26-28psi area give or take a psi.

That would actually be ideal. As for e85 and meth I already have that going. E85 from the pump which is generally high e70s and water/meth.

Anyways this will be my last post in regards to this thread for a bit. Take it easy.

compoundboost.jpg
 
I found this on an SVT site. It came from the internet so it must be legit, at least that's what I'm going to assume.

It's a boost reference chart for the result of turbo psi + supercharger psi.

So with my 10lb wastegate and 10lb pulley system, this should be in the 26-28psi area give or take a psi.

That would actually be ideal. As for e85 and meth I already have that going. E85 from the pump which is generally high e70s and water/meth.

Anyways this will be my last post in regards to this thread for a bit. Take it easy.

View attachment 70113

In Texas the E85 ranges from low 70% right up to mid 80% ethanol content. For the way I use it, it does not seem to matter much, the tuning window is much wider with ethanol. I have the knock sensor unplugged and just use an Innovate wide band O2 sensor and fuel pressure to tune AF ratio.

It made a huge difference in how cool my car runs.
 
I doubt anyone here has deleted their intercooler but on the off chance anyone here has, how have you gone about controlling air charge temps?

I assumed meth would be the golden ticket, like a magic pill that cures all ailments. I was wrong.

Just quick 3 second blips at 50-60% throttle cause air charge temps to rise over 210 degrees farenheit. I installed the largest meth nozzle and lowered the meth activation to trigger at just 1 psi to no avail.

I do not want to install an intercooler but I may end up having to do that. Should I consider adding a 2nd meth nozzle?

What are normal air charge temps for super coupes?

Finally, to follow up with the boost chart from the cobra site, that chart was spot on. I am seeing a total of 29psi with the turbo/m90 combo. It surprised me to see 29lbs at just 3400rpm. Everything was just in 1st and 2nd gear as I was simply driving on side streets to get data and make sure nothing would break while on a major road.20191111_171943.jpg20191111_171940.jpg20191111_172055.jpg20191111_172059.jpg
 
What are normal air charge temps for super coupes?

On my '90 Anny, I run a dual needle gauge that tells me air temp in & out of the IC... let's say as a general example, at 210°~230° in, I see 90° out. Hot day, hard pull, 7" IC fan on, I see 110° max out. I also run a narrow A/C condenser that allows fresh air direct to the IC.

We're told that "timing starts to get pulled at 120F and will have a full 8 degrees by the time you hit 180."

I seriously doubt you'll get where you need to be on meth alone...
 
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at 210°~230° in, I see 90° out. Hot day, hard pull, 7" IC fan on, I see 110° max out.

I seriously doubt you'll get where you need to be on meth alone...

Is this with a stock intercooler and stock piping or do you have a front mount?

I agree with you on meth not being up to the task of bringing the air temps down to low 100's from the low 200's. I don't have an air temp sensor before the m90, I am interested if the meth is even doing anything for cooling. At the moment I am going on the assumption that it's at least doing something since 29psi through a roots blower should, in theory, be well into the 300 degree territory if you use the 10* per psi rule of thumb.
 
Is this with a stock intercooler and stock piping

Stock IC and as I said, narrow condenser so the IC's airflow isn't double-stacked; stock IC tubes w/teflon gaskets, with a small patch of fabric heat shield on the return where it passes the exhaust manifold; 7" IC fan, MP raised top, 7% SC pulley, no cats, 13lbs boost on stock gauge.

I've run a total of 12% via an aluminum 5% jackshaft pulley, but with 15lbs. boost and incoming air temps at the IC hitting 275°, I decided to do my otherwise stock motor a favor, avoid off the slippery mod/on/mod slope, and stick with just the 5% SC pulley, instead.

And on the topic of the stock intercooler, and projected gains from something larger, see: http://www.sccoa.com/articles/cwintercooler.php
 
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Get a lighter waste gate spring that will allow you to only have 5 or 6 psi at the blower inlet. Yes add a 2nd methanol injection nozzle. What is meth/water ratio ?
 
I'm going to leave the boost as it is. This thing rips on 29psi.

Took it around town in the cool weather today. I can post a couple of data logs if you guys want. Not sure if you'll need megalog viewer or if any logger will work. It's all open source stuff.

I ordered a 2nd meth nozzle from Amazon for my aem meth kit. It arrived literally 20 minutes ago. I'll drill the m90 top hat and install the nozzle in the hat. I figure that's the best location for it to mix with the air.
 
what file hosting service do you recommend for uploading various file types? I attempted to upload my log files to this site but the site doesn't support .MSL files.

I have a 1000cc nozzle in the charge pipe going into the m90 throttle body, I am trying a 500cc nozzle for the 2nd nozzle in the top hat and see how the air temp sensor reacts to that before going with the 1000cc nozzle. The AEM nozzle from amazon came with 3 nozzles; 250cc, 500, and 1000 which is great for trying out the various sizes to see what works best.


A guy I was talking with on the megasquirt forums told me his experience with an m90 and no intercooler and the difference between spraying pre/post blower. He found that he needed to use an 18GPH nozzle pre-blower to get 140* charge temps as opposed to a 10GPH nozzle post-blower to get 130* air temps. granted he was running 14psi and not 29psi the basic concept should still be similar.

with spraying pre-blower the meth is cooling the rotors and housing as well as the air. spraying post-blower you're basically just cooling the air and charge pipes. I figure i'll try both and see how it goes.

That's really about all I've got going on lately with this car. No promises on track days. If it happens, it happens, I'll reply with the results whether they're good or lack luster. I'd like to take advantage of the cool weather so I'll try to push for a track outing sooner rather than later.

Have a good one.
 
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