You need to set the spring pressure, in the AEM Tru-Boost, lower than wastegate spring pressure. Otherwise the wastegate will be stuck all the way closed until 13PSI(or whatever your wastegate spring is at) creating fastest spool, but will spike at high RPM. You can even start at 3PSI and adjust gain and other functions to gain extra spool without inducing spiking. Adjust the spring pressure up until you start seeing a spike, then reduce.

Here's a link to the manual below.

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&u act=8&ved=0ahUKEwiGpLfvrfbOAhWB6iYKHbj8CF4QFghPMAE &url=http%3A%2F%2Faemelectronics.com%2Ffiles%2Fins tructions%2F30-4350%2520Tru-Boost%2520Controller%2520Gauge.pdf&usg=AFQjCNHGQKM t7LUyiEpVz2vboo_F1Bqx_Q&sig2=OSFQfUmZM-8wEIGNZtF3oA

I bought the tru boost for this setting alone. But if i set the "SPR" setting anywhere near the actual spring rate, it spikes.

Its not as bad as it seems. I get 9-10 psi around 3000 on the street and full boost around 4000. It still goes pretty good

10 psi at 3000 rpm sounds about normal for a 2560.
Your numbers are pretty good for a base timing map and actually seems aligned with the 2560 car Elior is talking about (I know the car as well). I bet that if you play with the timing you can extract a lot more.

I tune them exactly like this on purpose.

Id say add timing and some boost and move it to 280 odd.

Dann

Ive been busy moving out of mommy and daddy's house.. But now that driving season is over here in MI and I finished my garage, out the engine comes and time to make some more power. The plan is to run 11s on stock pistons, pdextra style. I will try to update once in awhile for maximum negcats :hatecat: Here is a condensed list of things I will be adding/upgrading over the winter
ID1000s
FM fuel rail
fuelab fpr
dw300
(e85)
manley rods
aftermarket rings + flex-hone
arp head studs
arp main studs
BE oil pump
Supermiata harmonic balancer
gtx2867 w tial .86 housing
Coolant reroute
https://cimg4.ibsrv.net/gimg/www.mia...8c00bb5733.jpg
https://cimg2.ibsrv.net/gimg/www.mia...79f6951473.jpg
https://cimg4.ibsrv.net/gimg/www.mia...2a12e5470e.jpg

Did you figure out the issue with boost creep on the ewg?

Side note: how'd you keep the torque low like that? Most of the gt2560s I've seen make a bit more torque. Original tune looked pretty good for a stock engine!

EWG wasnt creeping. It just builds boost slowly (when running spring pressure only) to resist over shooting the target level when you stab the throttle at high rpm..tip in or an up shift.

torque is low because of this. if it makes 200ft lbs with 10 psi...the torque will eventually fall off up top. Adding boost as rpm climbs will "resist" the falling of the torque. stupid f*cking stock IM

I actually bought thirdgen's old setup, which is a journal bearing "2560" with an ewg. Should be interesting to compare how that one ends up. He sent this thread to me a few days ago just so I could see what to expect.

WHY DOESNT ANYONE SELL AN OTS SHEET METAL INTAKE MANIFOLD FOR BP'S BESIDES FCKING BEGI. literally every other 4 cylinder platform in existence has a SMIM. especially mitsu and honda stuff. Someone. please. bolt on, lightweight, aluminum, mass produced, dyno proven, pnp, stock throttle cable, badass vacuum block on the back, 7-800 $$$

MUST BE NICE TO BE A FIRST GEN DSM OWNER. A QUICK $560 AND THIS IS YOURS
https://cimg9.ibsrv.net/gimg/www.mia...cb96e3a207.jpg

/rant

Use a honda mani?

Because the R&D costs to build half a dozen or more to figure out what works the best quickly destroys any chance of ROI in the miata community.

not much R&D....seems like a fabricator could copy the plenum size and runner length of just about any decent SMIM and it would flow better than the stock BP mani. I mean people are going as far as hacking up ebay knock off honda manis just assuming they flow better. Seems like plenty of people would pay $600+ for a bolt on mani. then again this is the miata community...

edit: probably not enough people making the power to actually justify one. Majority of turbo miata owners are happy with stock engine 250hp i guess

You are newer to the miata scene, so you don't know what has or has not been tried. Begi has done a ton of different testing of various designs over the past 10+ years. Unfortunately none have worked as good as they or anyone else wants. You either give up power low or mid end, to get top end, or vice versa. Or you end up where on a stock motor, it works worse then the stock IM, but on a built motor running more power, it starts to work well. For a while Begi sold a cast IM that worked rather well with built motors. They had problems getting them cast with a good quality at a price people would buy.

I have looked into building my own IM. Cost alone for materials and labor will most likely run you between $400-$600 per manifold. Welding aluminum is not cheap or easy. So figure you need to build 3-5 different manifolds, with different runner lengths, and possibly different box designs around then. Then dyno time for each one to figure out how well they work, and then being able to compare so you actually are selling a product that works, and works, how you want it to. So figured minimal $2000 in material and labor, then another $500-$1000 for dyno time. So you are looking around $2500 minimal in total R&D costs to possibly figure it out. Then you get to pricing them out. To make a reasonable margin on the IM they will have to be sold in the $700-$900 range. You would need to sell 10-15 IM minimum to break even on R&D costs. The market for IM in the miata world is not overly large. I can think of maybe 10-15 people total who will actually need one and be willing to spend the much money on one.

Also you have to remember that Soviet made 450whp on either the VICs or flattop intake manifold. So you can make more power on a stock IM then the transmission can handle.

why would you want an IM made for 10,000RPM peak power on a miata?

I dont. I just dont want the power falling off after 6k. Maybe the bigger .86 housing on my gtx28 will help with that. Or ill add some boost up in the rpms

There's a mazdaspeed ITB setup on the classifieds right now.

:firedevil

anyone know if this will work? so much conflicting info on deleting the heater core and coolant routing...

https://cimg2.ibsrv.net/gimg/www.mia...4ead3c4408.png

Are you running a flat top? If the intake manifold flows better up top there is a good chance you will loose low end torque.

Just add boost up top if you want the keep torque up. Also it's not like a 2560 is a huge turbo.


That will work fine for coolant routing.

*see post 25*

Just stock 99 mani. Going with a gtx2867 .86 ar exhaust housing. Goal is 330-340whp

I guess ill have to get it on a dyno and see how hard it falls up top before i think about a new IM.