Gtr's... Sequential Turbo Set Up?

[Phil Megroin]

Hi everyone,

After a debate with one of my friends we could not come to a conclusion on this matter.

Does the GTR have a sequential turbo set up?

by sequential i mean that it has a small turbo to spool up quickly, while the second, larger turbo kicks in after - to overcome the problem of lag and to give 'constant' boost..

I have always been under the impression that GTR's DID have a sequential turbo set up but after chattin to paulr33 (i think thats his name) he has seemed to convince me otheriwse..

[lwells]

No, GT-R stock setups are not sequential: that would be pointless given that both turbos are exactly the same size.

Lucien.

[Fly_With_Sky]

the GTR's use a true twin turbo arrangement meaning that it is NOT a sequential turbo system. So that is why the GTR's are more laggy down low in the revs as they have got each turbo working with only 1.3L and 3 cyclinders.

Toyota's 2jz-gte engine on the other hand has a sequential turbo setup, however, instead of having a smaller turbo matched with a larger turbo, i believe the stock turbos are the same size.

[Links]

A true sequential turbo system was the B4 liberty - they had 2 different sized turbo's and there was alot of complaints because there was a point in the rev range where the first one would cut-out and the second one had to spool out - meaning you'd get a second of slight power loss..

GT-R's are twin turbo - both spool @ the same time with the same boost levels..

[Phil Megroin]

yeah.. just as i was told

thanks for the info..

what cars are there aside from the B4 with a sequential setup?

[Loop]

The late model RX-7's use a sequential setup.

[lingeringsoul]

sorry to dig this up, but if twin turbo on GTR is abit laggy then wouldn't sequential turbo set up be the sollution? Does this set up work well for Rx7 at all?

[R31Nismoid]

The cost vs the results in doing such a setup simply put... isnt really worth it. It would require a fair bit of rooting around

Hence there arent a lot of cars around with this setup, as its costly.

Most people soon as they chase power, dispose of the sequential from the outset

[R-SPEC]

A true sequential turbo system was the B4 liberty - they had 2 different sized turbo's and there was alot of complaints because there was a point in the rev range where the first one would cut-out and the second one had to spool out - meaning you'd get a second of slight power loss..

GT-R's are twin turbo - both spool @ the same time with the same boost levels..

been as passenger in a mate's old B4. didn't notice any power loss, infact as soon as the 2nd turbo kicked in at about 4-5grand it would just push you back into your seat. thats how i remembered it anyway

[mrgilly]

been as passenger in a mate's old B4. didn't notice any power loss, infact as soon as the 2nd turbo kicked in at about 4-5grand it would just push you back into your seat. thats how i remembered it anyway

It's a pretty common annoyance for B4 owners, I test drove one and found it to be quite noticeable, just over 4K IIRC.

VGT anyone?

[wrxhoon]

It's a pretty common annoyance for B4 owners, I test drove one and found it to be quite noticeable, just over 4K IIRC.

VGT anyone?

I have found the same with the b4's, there is a hole at 4-4400 rpm.

[R-PWR]

I like the way it is in the GT-R's that way its perdictable

[R33silverS2]

It's a pretty common annoyance for B4 owners, I test drove one and found it to be quite noticeable, just over 4K IIRC.

I found this true also, a mate of mine has a legacy gt with the twin turbo sequential setup and between 4 and 5 grand it feels like its off boost. Seems kinda odd as they gave it a smaller turbo to be on boost earlier but then it lags in the middle of the rev range anyway...

[scathing]

It was a great idea from Subaru, wasn't it? Move the lag out of the low-end of the rev range, and put it smack into the middle of the rev range.

[scathing]

Several companies have tried to get sequential turbos to work, and most of them have failed. Whether its a torque hole during the transition (i.e. B4) or the convoluted plumbing that has a reputation for failing (RX7), eventually people give up on it.

I don't know why you'd want to have sequential turbos that are the same size (a la the 2JZ-GTE) - if you want something to spool faster before you get the big power, why not get a smaller turbine matched to a bigger one? If they're the same size you may as well put them in parallel (like the RB26DETT) rather than in series, and just use smaller turbos.

Of course, the new BMW 335 has a sequential setup and by all accounts its a smooth engine. I wouldn't mind taking one for a drive and giving it a go, but it might be a sequential turbo setup worth buying.

[eddieneedsboost]

Yeah as mentioned the 2jz uses sequential turboes of the same size, Toyota did this to gain low down power and anyone thats drivin a supra will also know around 4000RPM there is a drop in power when the 2nd turbo comes online.

Turbos have come a long way since the mid 90's tho hence the reason people put on big singles on the 2jz. A GT35R wont spool much slower than a stock sequential system on a 2j but will make alot more power.

There would be alot of R&D needed to make a sequential setup for a GTR, IMO money would be better spent on a 3L bottom end if you wanted quicker spool

Edited January 1, 2007 by eddieneedsboost

[PHATR32]

also turnign the boost up is a pain in the ass as you cant just turn it up, as that will make the point where the turbos cut in/out even worse....

good idea in theory though....