ColinRX7

So rebuild an FD engine and use a TII centreplate, and bam, bolt on REW (engine mounts anyways). No more cracking irons?

RONIN FC

Isnt the intake runner different on the TII and REW? Bolts different?

I thought there was a reason you cant do it but I dont remembr why

teknics

that would probably be the "strongest" motor, in terms of cracking plates. the REW rear plate, as i said, is only "stronger" because all the weight of the motor lays on it. Plus due to the mount being at the rear there's a lot more leverage on it too which increases how hevay the load feels.



kevin.

mazdaspeed7

How many fd motors do you see cracking irons?

CrassFC3S

haha yeah yall talk like cracking irons is a common occurance, i say just do it or shut up!

teknics

none. s4's only crack when theyre tuned bad anyway.



but structurally the strongest motor would be what colin described.



so if you plan on running on a horrible tune then it would be the choice for you.



we're not really talking about cracked irons, just waltzed off topic is all.



kevin.

ColinRX7

Well anyways if you goto the trouble of a rebuild, you can have an "FD" motor with FC mounts using the TII centreplate





That's really what I meant.. The cracking iron comment was for Kevman

mazdaspeed7

FC and FD intake ports dont line up. Dont expect to be able to use that combination without a custom intake manifold.





As for kevin's comment about it having to support extra weight, I disagree. To start with, the majority of the force is vertical, from the weight of the engine and gravity and bumps while driving. The extra bracing isnt in that direction, its in the direction that would oppose the block twisting under heavy load. If you really want to get technical, the vast majority of the load will be compression and tension loads on the tension bolts, bottom and top respectively. The shear loads on the dowel pins are well below the structural limits of both the dowels and the irons.



Ive personally been the witness to a s4 iron breaking in the dowel pin area, and Ive broken a S5 iron in the dowel pin area.

ReactionEffect

When you tear down 13B-BREW and 13BT side by side you will see the differences. Thats why I am building for my FC.

teknics

so you're telling me theres no reinforcement for the fact that the leverage on the engine mounting location is probably nearly double, nevermind the fact that a huge set of heavy *** twin turbos are now hanging off as well?



It's not like the brew was making 150hp more then the other blocks, hell if you put an s5 turbo on it i doubt itd make much more power then the s5. i really dont think they were sitting there saying "damn a lot of our stock cars' motors are being twisted apart and blown up by our regular customers"



I mean if youre mazda are you gonna worry about some car guy who is 1 out of a million, who if he does manage to increase the power to manage to create a load strong enough to produce a shearing effect and cracking the motor would be violating the warranty anyway. Or are you gonna be worried about the old guy dropping $40k on his brand new FD to drive on sundays and store in his garage?



Sure you can say they redeveloped it due to their racing program, but cracked irons = bad tuning. Im sure theyd fix their tuning before going out and redesigning what im sure is far from a cheap piece of the motor.



I mean im not saying youre wrong, maybe youre right whatever. I'm just saying there's no tech data on it that you can show where mazda says "it was reinforced to prevent cracking in the dowel pin area". So all we can do is sit here and say what it *LOOKS* like to us.



I feel it makes more sense for it to be reinforced for the extra weight due to the effect of leverage and the fact that the turbo setup is probably more then double the weight of the old s5 setup. Sure maybe when they went in there to fix that problem they increase strength all around, but i dont believe that was their main goal.



my opinion.



kevin.