[jojosmk2]

right now i have a 5m w/ a 35 shot of nitrous and i was wondering about a few things. i wanted to swap in a 7mgte block for lower compression and higher dispacement as well as using the mk3 turbo system on stock boost (what is stock boost?) also im gonna rebuild the 5m head and get it ported would the 7mgte block be able to handle that on stock internals? if not what needs to be done?

 

[zacknafei]

the 7m-gte block is a turbo block so it will take stock boost and a little laughing gas with no problems i belive stock boost is about 6-7psi for a ct-26, this combo has been done and works but requires a little fuel tunning,
and for sure a metal headgasket. when doing this combonation you use everything for your 5m except the 7m shortblock all accesorys are 5m, but im sure if you use the search button you can find lots of info on this setup

Scott A

 

[jojosmk2]

well im picking up the 7m block tomorrow. got it for 250 w/ all internals, then when i put the supra away for the winter ill be taking the head out for a full rebuild. also i plan on intercooling but would i need it if i was using the laughing gas seeing that will cool the air greatly

any more help apreciated

 

[84MKII]

yea stock boost is 7 psi

 

[Supra Bob]

ONe thing to be aware of... 5M is a 2 valve per cfylinder design. The 7 is a 4 valve, which means that the 7M pistons have 4 smaller valve reliefs instead of 2 larger... Not an insurmountable problem... but one to be aware of.

 

[Muchbzy]

ONe thing to be aware of... 5M is a 2 valve per cfylinder design. The 7 is a 4 valve, which means that the 7M pistons have 4 smaller valve reliefs instead of 2 larger... Not an insurmountable problem... but one to be aware of.

What this really means is that the engine is now a zero tolerance motor. If the timing belt goes it takes the valves with it and maybe more.

 

[zacknafei]

i was under the impression that a 7m block 5m head hybrid motor was non-interference, although i dont know why..)
Scott A

 

[suprarox85]

it is but it is recommended that you swap to the 5m pistons so that the valves and valve releifs dont battle it out and claim your new hybrid

 

[jojosmk2]

yea but if i put in the 5m pistons then i wont lower compression right?

 

[suprarox85]

if im not mistaking the compression on the older mkIIs are higher and after 84 i think it is(dont hold me to it)the went to lower compression pistons but if you are going to build this motor to be quite strong you may want to look at getting some custom forged pistons made so you can get it done how you want