GT2554R, Suitable?

[Jules-B]

Hi all

Im looking at building a forged engine running a GT2554r. I have been looking at the compressor map for the turbo http://i231.photobucket.com/albums/e...xx10/gt25r.jpg

and it looks like ideally looking at making around 170bhp at 0.8 Bar. I know you cant really predict lag from looking at compressor maps, but maybe some of the Malta boys might be able to tell me if it would be laggy or not?

And what kind of boost could i run on one of these tubbys

Thanks for the help

Jules

[ecksjay]

GT2554R is quite a large turbo for a 4E, i assume you're going 5E? Even considering that, it'll still be quite laggy. it'll EASILY produce 170bhp, but that turbo is used for 300bhp on an sr20, so will be very laggy and well under its efficiency curve if forced to run only 0.8bar on a 4E.

abbott is running a GT2530, and that is rather laggy from what i understand, a GT2554 will be larger again, and hence, even laggier. He produces good power (around 220-240bhp from memory), however he's running it at a fair old whack, so is making the most of it.

[Jules-B]

I was of the understanding that his was a hybrid running a gt25 inlet and gt30 exhaust side, and that dispite the numbers it would be less laggy than his gt2530.

I may be totally wrong here though, and i was only going on what i have been told about reading compressor maps. i will be running a forged engine so will be able to run the turbo to its full potential. this is the one im looking at, shows the size etc.

http://www.turbobygarrett.com/turbobygarre...4R_471171_3.htm

some of this stuff does confuse me, and i have had a few this evening so i may be tottally wrong, i want a high response turbo, that i can run to full potential, with power fc, forged 4e, lightweight pulleys, lightened flywheel and knife edged crank.

[ecksjay]

i believe his is a gt2530, i think he discussed having it hybridised but it is definately a gt2530 in essence.

those types of turbos are relatively laggy on an SR20 (what they were designed for), so on a 4E then they will be even laggier, it'll never be a 'high response' setup unfortunately, thats just the way of the world.

High response would probably need to be a hybrid smaller turbo of some sort, GT2510 is smaller and would probably run decent bhp whilst being responsive, as its pretty much instant on an SR, in honesty you'll never truly know until its bolted on, it's treading new ground really and the only way to know for sure is to try, as the specs of everything will affect it all in different ways.

Most responsive high-bhp starlet i've ever been in was a Hybrid TD04, around 270bhp and still very responsive, no real noticable lag, that was a completely custom turbo however, built at great cost specifically for that engine to particular specifications. Very impressive however, think it was a TD04/VF series hybrid.

For response ideally you should be looking at the 5E route, they do produce that little bit more torque and give the extra grunt which does help with low down power, gets the turbo spooling that little bit quicker.

[TBDevelopments]

you guys do realise you using both new and old generation garrett names in the same thread, so this could be a little confusing

Tim

TB Developments

[turbominicooper]

can I revive this thread and see if anyone has got a gt25r on there 4e? what's the opinion if so, spool up time etc?