Throttle body question (1 Viewer)

[locrwln1]

Ok, so I am still working on actually buying my 80, but I do have a question.
A little history, I sold my '88 3.0 4runner. The mods to the drive train were geared toward rockcrawling. You know the usual SAS, dual cases, 35's, arbs, trail armor including an arb front bumper, OBA and on and on. Anyway, back to the 3.slow. I put the downey headers, high flow cat and magnaflow muffler on it. I left the ignition alone, everyone told me stock was as good as it gets. I put a k&n in the stock airbox. Those mods made a signifigant difference in power. The final piece was a 3mm overbored throttle body. That also made a nice seat of the pants difference. It would run 70 mph over Donner Summit outrunning my buddies 4.0 jeeps that were built along the same lines. I haven't seen anyone do anything with the throttle body on the fzj80. Has someone done it and I didn't find it or has it been tried and no benefit was noticed? I just see guys going toward porting and polishing the heads and everyone saying that headers would/don't do anything. I'm not looking at doing anything right away or if ever. My question is, has anyone approached this as a system, ie. throttle body, headers, etc? It just amazes me that every manufacturer's intake/exhaust can be improved (including other Toyotas), except for land cruisers. How did they make it so that there is no improvement to be made. Discuss.

 

[bjowett]

The throttle body may or may not be a bottle kneck on the stock engine. No one(?) has spent any time dyno tuning the 1FZ in normally aspirated form to get some results... IMO there is a chance of some gains there. My engine build includes increasing the size of the stock unit, which measures about 63mm.

The stock exhaust manifolds are decent enough, though I think the downpipes (man. to cat.) are a restriction that needs attention.

 

[locrwln1]

The throttle body may or may not be a bottle kneck on the stock engine. No one(?) has spent any time dyno tuning the 1FZ in normally aspirated form to get some results... IMO there is a chance of some gains there. My engine build includes increasing the size of the stock unit, which measures about 63mm.

The stock exhaust manifolds are decent enough, though I think the downpipes (man. to cat.) are a restriction that needs attention.

Cool, I have been following your buildup, nice work. I would think that with the bore increase and head work, that some thought should be given to the complete package. I know that RC Engineering (who did the overbore) limited the 3.0 tb to 3mm for primarily stock motors. You go up as the mods go up.

 

[locrwln1]

Wow, quick discussion.

 

[bjowett]

The overall consensus on here seems to be there are no gains with bolt ons, t-bodies, headers, exhaust etc. This creates a limted market for items such as these. Is the consensus wrong? Good chance...

I usally try to approach buildups as a complete package, and this one is no different from ones past. Displacement increase, port and polish, the intake manifold has been reworked, bigger t-body etc. The stock exhaust manifolds will probably get a little attention and some custom downpipes and exhaust will top it off, maybe dual all the way back, inline six cylinder engines can sometimes see a nice gain from that alone.

 

[locrwln1]

I agree with you 100%. If approached as a system, how can you not gain some power? I mean really, this stuff works on every other motor out there. I was just curious if anyone had tried it and how toyota got everything sooo perfect on this motor. There are improvements to be made on the other toyota motors, but apparently you can only turbo/supercharge this one. Just curious.