I rev my 87 with the 6500 rpm to damn near 7 grand when I bounce it off the limiter once or twice. The aluminum flywheel and drive shaft are conductive for the ignition not cutting in quite in time after the 2nd or 3rd time off the limiter. Doesn't hurt anything, Toyota built in a hefty safety margin I'm sure.
Rev Limit
- Thread starter dumbo
- Start date
I have the 7M crank (and a lot of other goodies in the engine),
and I run mine to 8500........
ECU can have the clock crystals changed to raise the rev limiter.
But don't do it without building a good strong engine.
I send my ECUs to a guy in Florida by the name of Kieth Goldin
He charges $110 to change the rev limiter, and ship the unit back to you.
His e-mail is keith.goldin.co75@statefarm.com
and I run mine to 8500........
ECU can have the clock crystals changed to raise the rev limiter.
But don't do it without building a good strong engine.
I send my ECUs to a guy in Florida by the name of Kieth Goldin
He charges $110 to change the rev limiter, and ship the unit back to you.
His e-mail is keith.goldin.co75@statefarm.com
<< one of the few that have ran both cranks identically prepped in the same engine weeks apart with the crank being the only change due to a communications breakdown with my crank shop 
6M Snappier acceleration
7M Smoother across the rev range until 6500 then there was little difference to be felt.
Turned all 3 to 8300rpm
6M
7M
7M FrankenCrank
6M Snappier acceleration
7M Smoother across the rev range until 6500 then there was little difference to be felt.
Turned all 3 to 8300rpm
6M
7M
7M FrankenCrank
gofastgeorge;1473695 said:
YOU ARE AWESOME! Thank you
Hmmm makes me wonder if I should use the crank out of my GE block, IJ did you ever wheigh them? Can't seem to get solid weight.
Poodles;1473702 said:
This is the first i've heard of adverse effects, can you educate me beyond the 'don't do it to stock engines' info?
Change the clock and it changes ALL the calculations the ECU performs....
Adverse or not it's a change, I'd only be comfortable running an engine to the edge if I understood what those changes were and what the results were.
Perhaps 3P and the boys could look into this and post some data.
Adverse or not it's a change, I'd only be comfortable running an engine to the edge if I understood what those changes were and what the results were.
Perhaps 3P and the boys could look into this and post some data.
I sent him a pm IJ so hopefully he puts his two cents in here. This seems like a very good option for me, but would like to know the whole story. Don't wanna blow up my new engine right away.
<nodding> Not saying it's good/bad/otherwise just that I don't know or understand the full effects and I'm not keen on rolling the dice on unknown variables based on ancedotal evidence.
I wouldnt push the 7M series rev limit I used to then after me & my brother, couple other friends put pistons through the side of blocks we switched to JZ series, It either cant take the stroked out force, or the oil system haves some inadequacies.
I would look to gain HP or fun from other methods then boosting the revs on a 7M.
I would look to gain HP or fun from other methods then boosting the revs on a 7M.
IIRC, messing with the ECU's crystals has adverse effects on timing, and was hit or miss. RacerJake used to do the crystal mod for 7M's, but stopped because there was no definite way to make it work every time. He started (and still mods) the MR2 ECU's, which apparently are similar to ours.
Poodles;1474021 said:
I'm more than happy to read, i just don't know where to look is all
Thanks much for the effort Poodles!
Ive read on quite a few forums that, increasing the rev limit, increases everything else the ecu does. Meaning fuel, rev, timing....so I would say if you do it, be prepared to make other adjustments as well.
None of it is facts, just stuff Ive been reading....I want a rev limit of 7k rpms. And I wanted to know the cause and effevt of the ecu mod.
None of it is facts, just stuff Ive been reading....I want a rev limit of 7k rpms. And I wanted to know the cause and effevt of the ecu mod.
Pretty sure the stock hard limit is 7000ish, ignore what the redline on the Tach is I'm talking about the hard cut.airhead04;1474136 said: