[Mk2] [Turbo] Maximum Rev Limit

[Turbonoz]

Do you monitor oil pressure at those high revs? The only real issue I can see would be the oil pump not being able to keep up. If you are keeping the det at bay, rev it to 8000rpm and monitor the oil pressure.

That's a good point, cheers

It is the cams that will determine where your max power is, nothing to do with size of turbo or boost.

The whole point though is that it's a standard engine with standard valvetrain. The cams are a constant, as is the huge turbo, for the time being. Variables are boost pressure & tuning (inc. rev limit). It's not about spending massive amounts of time or money, I just wanted to strap a huge turbo to another engine and see what I can get out of it with it still in one piece. It's just a laugh. If the car hadn't gotten into the 12s, I'd have scrapped it, bought my mates FC and swapped everything over onto that. Having raced his FD-engined bridgeported T88-powered FC, Rotary>>>>pistons any day

Once everything is maxed out, it will be cams, inlet and maybe headwork, and then see what the stock block will really do. Probably for next year. Conversely, my Pulsar is running 264 HKS cams and pulls a 12 flat at a higher terminal with just a tiny T28

[greeny]

It should be the stock rod bolts that'll cause you problems first at higher revs.

If it was me I wouldn't want to take it above 7.5k on stock bottom end.

As for valve float, I've no idea when it'l become a problem.

I've got no choice, I'll be forever stuck in the 12s with a 7.5k limit 'cos the turbo is too damn big

Boost off the line and some slicks

[Turbonoz]

It should be the stock rod bolts that'll cause you problems first at higher revs.

If it was me I wouldn't want to take it above 7.5k on stock bottom end.

As for valve float, I've no idea when it'l become a problem.

I've got no choice, I'll be forever stuck in the 12s with a 7.5k limit 'cos the turbo is too damn big

Boost off the line and some slicks

Heh, I have launch control with a soft & hard cut which gives me mild anti-lag and it'll produce about .4 bar at 4700RPM stationary. Only got semi-slicks to keep it in the road-legal class

I'm going to try a 6.5k launch as I didn't break traction at 5.5k.

Is yours up & running this year?

[greeny]

I've got no choice, I'll be forever stuck in the 12s with a 7.5k limit 'cos the turbo is too damn big

Boost off the line and some slicks

Heh, I have launch control with a soft & hard cut which gives me mild anti-lag and it'll produce about .4 bar at 4700RPM stationary. Only got semi-slicks to keep it in the road-legal class

I'm going to try a 6.5k launch as I didn't break traction at 5.5k.

Is yours up & running this year?

Hopefully will be somewhere near by the end of the year. Just time at the minute!

Expanding my business amongst other things, so unfortunately my toy comes last!

Edit. I'd certainly put some rod bolts in it and then I'd be tempted to take it to 8k. Be interesting to see how it does!

[2barGee]

It would be great to see what power it's putting out now as well ..... Get it on a dyno

[ashley]

Edit. I'd certainly put some rod bolts in it and then I'd be tempted to take it to 8k. Be interesting to see how it does!

^^This! A set of ARPs on there and you should do a safe 8k on stock rods for not much £££

[Turbonoz]

I take it the bolts can be changed with the engine in-situ easy enough?

[ashley]

I guess you could do it in situ, I've never attempted to though

[Peter Gidden]

I take it the bolts can be changed with the engine in-situ easy enough?

Yes.

[Al-sw20]

Yup have changed big ends in situ, so should only be a little more work than that

[Ja99a]

I understand the biggest issue with High RPM on the REV1 - 2 3sgte is the over shim arrangement. it has the chance to spit a shim.

I am sure this will be a controversy...

I have my Limiter set at 8250 with under bucket shims (rev3), use the shims from a ford Puma they are loads cheaper and fit perfectly with a larger range of sizes.

My turbo is all blown out at 7500 so it's better to shift than hang in there ragging the setup.

[Turbonoz]

I understand the biggest issue with High RPM on the REV1 - 2 3sgte is the over shim arrangement. it has the chance to spit a shim.

I am sure this will be a controversy...

I have my Limiter set at 8250 with under bucket shims (rev3), use the shims from a ford Puma they are loads cheaper and fit perfectly with a larger range of sizes.

My turbo is all blown out at 7500 so it's better to shift than hang in there ragging the setup.

Fancy a trip to Santa Pod this weekend mate?

[kingsley]

My understanding is that max power is around 6250 rpm on a stock engine so there no point in going higher.

I disagree with that. You accelerate better if you rev past the max power rpm as long as the power curve isn't dropping like a stone. That way your revs are high enough when you change into the next gear to still be making good power.

Assuming a normal "single hump" style power curve, you rev to X rpm in (say) 3rd and the moment you engage 4th you're doing Y rpm. Max power rpm is somewhere between X and Y, and power at X equals power at Y.

You maximise power over time that way.

Cheers,
Kingsley.

[kingsley]

After all, it is high-mileage & bone stock (apart from a metal head gasket) with a T78 strapped to the side of it.

Holy wotsits, a T78?!! Sorry to wander off topic but when does that start spooling, and when do you get decent boost?

Those are laggy and have a high boost threshold on an RB26 let alone with 2.0 litres!

Cheers,
Kingsley.

[Turbonoz]

After all, it is high-mileage & bone stock (apart from a metal head gasket) with a T78 strapped to the side of it.

Holy wotsits, a T78?!! Sorry to wander off topic but when does that start spooling, and when do you get decent boost?

Those are laggy and have a high boost threshold on an RB26 let alone with 2.0 litres!

Cheers,
Kingsley.

Haha, yeah it is overkill and is probably costing me a good 1s down the strip, but it's staying til the end of the season. Hopefully I can get into the 11s which I'll be happy with for now. Next year I'll drop down to a GT40 and think about WI.

It's not too bad on the street, but it only runs up the strip at the moment. With the launch control set at a modest 4800rpm it'll generate 0.5 bar on the line. According to my logs, I'm getting 1 bar at 5500rpm and 1.6 bar at 6250rpm. Limiter kicked in at 7773rpm. Peaky!

This coming weekend the air temps should be about 15° lower than last time. I've tightened the spring in the wastegate as my Profec B was maxed out. I've further refined the map and switched to a hard cut rev limit as oppose to the soft & hard I was running. I'll be increasing the launch RPM to 6500 and going for a 1.7 60ft Last time out I went from 13.6 to 12.8 just with mapping, which saved the car from being scrapped as I had promised my mate if it didn't hit a 12, I was done with it. It's still slower than my Pulsar (and probably my Zed, too), so it's skating on thin ice

I was hoping to have sorted my side exit (3" pipe straight off the turbine housing) and fitted some ARP rod bolts, but spare time is taken up with websites, ECU diagnostics & mapping my Zed at the moment.

[Turbonoz]

Kingsley....

Hahaha, this is a blast from the past... Remember rinsing a white Sapph Cos in your R33 down the A45 no less than EIGHT years ago??

http://www.gtr.co.uk/forum/23710-grey-r ... a-pod.html

[kingsley]

Kingsley....

Hahaha, this is a blast from the past... Remember rinsing a white Sapph Cos in your R33 down the A45 no less than EIGHT years ago??

http://www.gtr.co.uk/forum/23710-grey-r ... a-pod.html

Hi, yes I rememeber that

Jeez it doesn't feel like 8 years ago though - now that's scary!

Cheers,
Kingsley.

[Turbonoz]

Will be keeping the limit at 7800rpm with stock rod bolts for the time being.

ARP rod bolts are not a standard Toyota engine component, and that would be cheating

[synXero]

Is a '78 a stock engine component?

[kingsley]

Is a '78 a stock engine component?

No, but neither is it a bottom end or valve train component. From his original post:

Standard bottom end & valve train components.

Cheers,
Kingsley.