Shoot, I can barely light the mix below 10.0 AFR!

 

The whole timing issue sounds VERY fishy to me. The pulley and hub should be used as a set because of the way Mazda manufactures them.

 

+1. Learned about this the hard way several years ago. Took me awhile to finally figure it all out.

B

 

I didn't get to it last night as I wsa trying to get some mani's prepped to go out for ceramic coating. I'll take two pics, one of a Cosmo front cover next to an S4 n/a. Then I'll take the S4 core motor that just went on the stand line the pulley up with the pin. Replace that pulley with the FD pulley becuase that has the Cosmo marks on it and see what happens.

Sounds like Brian had something very similar happen to him though

 

Well, the pulley and hub are both re if that helps. I don't even think the re pulley can be put on the s5 hub but I could be mistaken.

 

if the e-shafts are interchangeable than the hubs should be as well. That's not to say that they will line up properly though. There are machined slots for the keyway that need to be clocked correctly with the four mis-spaced bolt holes for the pulley as well. They are mis-spaced so the pulley that contains the timing marks can only be put on one way keeping the timing marks in place.

While I agree with Arghx that the pulleys should only be used with the corresponding hubs, I also can't see why Mazda would change the hub design if they didn't need to. Why change the pulley and the hub when you only need to change the pulley? Cuts down on costs.

Now, with that being said it appears what I will also have to do is after I put the Cosmo pulley on the S4 hub, I'll also need to put the cosmo pulley and hub on the S4 motor and make certain there is no difference in the hub either. Anyone thing being different will throw the timing way out of whack and that's what I think happened using the cosmo pulley with an S5 front cover.

 

I hear you on the costs thing, but a little info that may pertain to this which I discovered while searching for TDC during the TECgt install:

S5 eshaft with S5 Hub + S5 pulley = good

S5 eshaft with S4 hub + S4 pulley = a little off

S5 eshaft with S6 hub + S6 pulley = a little closer, but still off

Never used an RE hub or pulley OR front cover, so can't comment on the pin location, but I know that all the other previous (S4, S5 and REW) hubs had a minor difference in the keyway. This could be observed by stacking the hubs, and sliding the key way down them all....you'll see they bolt holes "rotating" as you go up in years....

With that said - i'd bet money they're different, every other freakin' one is!!

 

I should have just stayed with the s5 pulleys. I'm getting it back on Tuesday so I'll be checking in the mean time to see if I have the s5 pulley.... Crap I'm going to need a dual FD alternator pulley as well. I have a feeling you guys are right. I mean the RE thing has constantly been a thorn in my side and that's why I get for trying to reinvent the wheel. Dual pulley is all that's need to prevent slipping.

 

I suggest a RB main & alternator pulley; that way you eliminate the guesstimate on pulleys vs hubs. I went through it a couple of years ago, and got tired of trying to figure out which one was which, so I broke down and bought a serpentine pulley kit

 

hum..... Thanks for the info I'll check it out! Anything that'll fix this problem

edit you talking about this?

Aluminum Main Drive 1974-92 (all)
Double Sheave Pulley

 

it seems to me that you actually have TWO problems

1. it does not run right unless the afr is in the 9's

2. with 9:1 afr and 20psi of boost, the fuel pump is maxed out.

#1 is the worry, step one would be to verify that the afr is right, then????

#2 is pretty simple, to do a volume test of the fuel system. i have seen bad bosch pumps before, i could believe a misassembled AN line, clogged filter, poor pump voltage. its all easy to check.

 

There you have it. I'll still get the pics though as the pin location can have ALOT to do with it as well

GREAT info Joe

 

Here we have an S4 front cover to show the pin location




Here we have a Cosmo front cover showing the pin location



S4 front cover, S4 Hub, S4 pulley



S4 front cover, S4 hub, COSMO pulley. After I saw this I took the pulley off and put the S4 pulley on to make sure that the e-shaft hadn't rotated. It didn't. I believe your timing is off



Now, what I would like to know as I would like to do this to double check..... how does one find TDC on a rotary? While the motor probably wouldn't like 0* timing, it would be nice to be able to have 2 points to check timing at. One from the factory, and then one that we add.

 

Timing marks:
http://www.yawpower.com/pultime.html

TDC:
http://www.yawpower.com/dectech.html

 

Nice pics!

I've heard of alot of methods of locating TDC varying from jamming pencils in the spark plug holes to using liquid measurments to boreoscopes......but personally, in my quest for TDC and a pulley/hub that would keep my (S5) engine there I broke down and assembled one half of a keg on the stand, set it at TDC, and went from there.

At that point you could add marks whereever youlike....a line or notch on the shaft works best IMO. All I did was put a teency mark on the front cover that matches with the leading edge of the keyway while in TDC.

Basically, I wouldn't trust much of anything when it comes to pulley/hub combos given the variance I've seen, so physically lining it up with the parts in your hands is the best and most accurate way IMO.

 

Thanks, previously read both those articles and neither tell you how to find TDC on an assembled engine.

The only thing mentioned is that @ TDC the keyway is @ 90*. Now is that true for ALL e-shafts?

Thanks. I like your approach but unfortuneately like you said, with all the variances I believe it would be possible to have differences between the two engines that you built unless you're CERTAIN that the pulleys, hubs, and e-shafts are correct. With my used/imported motors, I just can't be sure.

What I'm going to do becuase this is causing me some concern is when I'm assembling my engine, I'll put the front iron on the stand, drop a rotor on, drop a housing on, bolt the front cover on, put the hub and keyway in place and rotate the engine to TDC. Make a mark on the pulley, and then taking your route, put a mark on the front cover that lines up with TDC.

Following Pauls destructions for additional timing marks, take the pulley off and find 5* and 15* and make sure they correspond with the marks that are already on the pulley. If they don't, I'll curse alot and throw the pulley into a wall.

 

I don't think it's the best method but i bought a RB one piece pulley and got an old first gen 12A cover. I use that to verify all the marks on my pulleys because i know it's accurate. The cover was free and the pulley was $79 IIRC. It's a small price to pay for piece of mind. My only worry now is that all the keyways are the same trough the generations

 

+1. I've done the exact same thing, Allen. I copied it by putting a hub and crank pulley together and chiseling known-good marks on it. I use it as my reference piece.

B

 

i never blew up any rtek car, get your facts straight

 

Ummmmmmmm, OK. I'll believe the close friend with no reason to lie about it, thanks.

 

Must be a pretty good method as I do the same....

 

well. i believe him not you. if you can't say who it was or pm him? then both of you(you and friend) are lieing and i believe its actually called slander(but i'm not a lawyer by any means)

 

on the subject of timing marks then,

would installing an RB pulley on an s4 T2 motor (s4 T2 front cover and eshaft) essentially mean that accurate timing marks are guaranteed? Also, what are the disadvantages to the RB pulley? Will it slow my alternator down, reducing voltage? I do not want to try and find TDC myself.

I am willing to pay $79 for accurate marks if that's what an RB pulley will get me. I am not 100% confident on the pulley that was installed by the previous owner.

 

Sorry guys I didn't duck out of the conversation I'm just waiting on the car to come back so I can let you guys knows what the deal is. I do appreciate all the advise so far and NotTTT Thanks a ton for the pictures!!! I'll be sure and report back as soon as the car comes in next week. THanks again.

 

Excellent, you're welcome. I noticed last night when I cracked open an S4 keg that the keyway is @ 90* (or 3 o'clock when looking strait at it) @ TDC. How that translates to other shafts, I don't know. What that means for the front hubs, I don't know. I would think Mazda would make something common between them all, perhaps it's the keyway @ 90* that makes TDC and the hubs are all slightly different as Classic found. Paul Yaw's article seems to indicate that all e-shafts are at 90* @ TDC.