Jeffs MSP GTR Build

[vtec-this]

OK THIS IS HOW YOU TELL IF YOU HAVE A BIG OR SMALL NOSE/BOLT PULLEY



You may notice that your BIG NOSE/BOLT pulley has a plate on the front. That is fine and does not mean you have a small nose.(this is where I screwed up I thought if you have this plate its a small nose, dont go by the plate go by the size of the bolt)



In the above pic u can see the big nose pulley with front plate install (its just super rusty) is very similar to the plate I am holding from the small noise pulley. Dont let this confuse you. Always go by the size of the bolt used to identify the pulley.



Left is a miata UDP pully
Center is a SMALL NOSE pulley
Right is a LARGE NOSE pulley with front plate that looks just like the plate on the small nose



EVERY LARGE NOSE PULLEY I HAVE COME ACROSS HAS A DIFFERENT BACKING PLATE PIECE (the part that is held by the 4 x 10mm screws). Just use whatever backing plate your engine came with.



Just to reiterate this again, my GTR, the miata 1.8 large nose and 2 x Escort GT LARGE NOSE all had slightly different backing plates that get held by the 4x10mm bolts and have the groove for the key.

Is there any advantage to using one plate over the other?

My guess is probly not. They look 99% identical, just slightly different thicknesses/design. If I weighed them all maybe there is a slight difference but it isnt much.

I believe you can use any of the big nose plates with any of the big nose pullies. Im just sticking with the one that came on my motor and keeping the others as spares.

[vtec-this]

wideband is back in. I have been tuning all week to/from work. my fuel consumption is amazing. im using less gas than I ever have before, even compared to my n/a tune with 230cc injectors (im on rx7 550s now)



Just wondering if anyone has any input on my target AFR tables. Keep in mind im still not the greatest at this. FYI I keep the idle a bit rich to help keep thing running smooth when I turn on the lights/fans as I have no idle valve.

i looked at some guys over on the miata boards and started copying their values.

now the car is running really well with these targets.

i have that lean cruise spot where I spend most of my time when cruising in 5th between 75-110+kmph. Currently getting over 40MPG on my best run when I drive like a grandma in 5th. (keep in mind only 2600 pounds, no AC, No PS, superlightweight right foot when cruising)

I was advised from a member on another board that 16:1 in cruise is pushing it so i backed down the slightest bit to 15.8

Then under boost Im staying well on the safe side Id say. I

I am EXTREMELY happy with how the car is running, but I would appreciate any input you guys have!

[Mazda_Powered]

I idle at 15.4-15.6 and it's fine without my IAC hooked up, otherwise those values seem pretty spot on, hows your ignition timing doing?

[vtec-this]

Pretty sure this came as the stock timing map for Lex's PnP setup. I dont remember messing with it as I started from a "fresh" premade by Lex map when i swapped to 550s, but I dont have any of the original files handy to compare they are on a cd somewhere in storage.

[Mazda_Powered]

seems fairly safe for timing! I bet it's a blast to drive!

[vtec-this]

ya it sure pulls hard.

Have not had a ticket in a long time. Got a speeding ticket last night. I guess it is time to calm down lol

[Mazda_Powered]

uh oh haha, hopefully wasn't too bad!

[vtec-this]

going to dyno at steeda next week.

they have a Mustang Dyno 1750SE (Single Eddy Current).

should be interesting to see what my 22 year old motor that has been through hell and back a few times puts down to the wheels.

[vtec-this]

the good news..the motor is making much more power per psi than it ever has before.

the bad news, im starting to get sputtering under high boost over 5K even with relatively safe AFRs..

only got 48 hours before she will be on the dyno. Going to grab a fresh set of NGKs on lunch today and hope that cures the issue.

Currently running-stock Ignitor to MSD Blaster2 coil, stock distributor, Bosch spark plug wires (could this be the weak link?) and NGK BKR7E. I was at 0.030 before, dropped em to ~0.026 and was still getting the misfire/studder.

Running out of time to sort this lol

[Boosted Escort]

i have heard that the stock coil is better than the msd stuff. Might try dropping your spark gap down a little more just to see what happens it might help.

[Boosted Escort]

I would try the wires first though.

[FE3-323]

your spark gap is too small. your plugs are too cold of a heat range. and you should put iridium's in it.........
use heat range 6 iridium plugs. & maintain at least a .3x gap.

[vtec-this]

the new plugs are the 4644 ngks. I just picked em up. They are replacing a worn set of ngks. After a few weeks of tuning they look pretty much shot. I am going to try these new ones tonight with 0.03 as you are suggesting and see if there is any difference. If not I gotta try and figure this out tomorrow. 13.5psi it runs great, 14.5psi and it starts stumbling. The lowest the AFR is going is 11:1 near redline, im still working on the tune. Ive run much richer than this and it didnt stumble so Im thinking\hoping its just the plugs.

have you had better luck with range 6 than range 7? I would figure at 1bar on a big turbo I was supposed to be range 7 or even 8..Im on a stock internals ~9:1 EGT motor so I figured the slightly increased compression would warrant a colder plug more so than when on a gtr/gtx bottom end.

[Mazda_Powered]

4644 are the perfect plug to run in the BP, they seem to love them.

[vtec-this]

well the new plugs worked good. everything smoothed out a bit and it is no longer sputtering in high boost.

but of course ive found the next weakest link. around 14-15psi the clutch started slipping in 3 and 4 after a few hard pulls. The clutch is a clutchmaster stage 2 6 puck. I believe it is rated to ~250-275 foot pounds. I am just going to set the boost around 13psi and see how it goes on the dyno.