WS6HUMMER

iTrader: (19)

It was embarrassing! What a massacre.

TINKRD

iTrader: (27)

M6 car. and you're 100% correct. spools faster on the road then on the dynojet.

http://www.youtube.com/watch?v=1FOnzonT6qI

http://www.youtube.com/watch?v=M8WSxuD7dfI

http://www.youtube.com/watch?v=5lXEUEycOyA

corpserodeo666

iTrader: (12)

I have ls9 gaskets and ARP in my 408 and I'm running a s91 with 1.32ar and I have had no issues so far. It seems a little laggy in the get go but when 2800-3000rpm hits it moves like no tomorrow.

konceptracin

What psi are you at and what kind of boost
Controller?

corpserodeo666

iTrader: (12)

I'm at about 25psi and I have an AMS 500. I just got the Holley Dominator EFI system. I will see how that works out for me.

konceptracin

Dam on 4 bolt heads? Lq9 block?

corpserodeo666

iTrader: (12)

Yeah. Its not like I drive it always at 25psi but yeah its not crazy. There are plenty of people on here who can make that power and even more on a setup like mine.

konceptracin

What kind of power did you make?

konceptracin

Also who did your turbo hot side?

Louis

iTrader: (7)

The nice thing about singles that make big power- they lack the torque that two small twins make.

Whats that do? Keeps cylinder pressure down in the early RPMs. Which in turn helps keep the heads on it.

PRAY HRD

iTrader: (119)

subscribing........i find it a bit funny that anyone could think that a 4788 wont work on a 408 when there's a couple on here running mid-low 9's on a little pt88 with a t4 housing. granted it isn't the Most ideal turbo but will you make enough power to run 8's? hells yea! i will be finding out exactly what mine will do on my 402 if i don't sell it first for a forged 370 but i will be running mildly ported 317's with about 10.25:cr and standard ARP studs.

i spoke to mike at AES the other day and he said with my goals of staying 20psi max, i will be fine with the ls9 gaskets. to do the 1/2" studs, as another said a couple pages back, Mike said they would have to do a complete teardown so it's not worth it at all to me for my goals of an 8.99 or faster street first, track second car. i will be starting out with the .96 ar that was on the turbo when i picked it up slightly used (handful of 1/8 passes).

the rest of my setup is also similar to the op's with a built th400 w/brake and a mwc 9" and 3.70's but i will be swapping out to 3.25's to be able to cruise at a more reasonable rpm. cam will be an EPP/Brute Speed blower cam and vic jr intake w/81# injectors.

can't wait to see the progress OP and on yours as well as others craig!

JLE58

So what is The best Cubes For the GT4788 ? We know it works on a 408 but what would be ideal?

PRAY HRD

iTrader: (119)

i can tell you that mine came off a mod motor 283 ford and ran 8.50's and wasn't reaching it's potential yet but idk the boost level or anything else about the combo so i would say probably 283 on up to 370 is best suited for all out. that's strictly an opinion and i'm sure others will chime in on that. the guy sold the turbo as it didn't fit whatever class it was he was shooting to compete in.

konceptracin

PRAY HRD .... I will start posting some picks of my build up when I get back in town ! I'm going with the 4788 or the 91 not sure yet it will be a last min thing!!! How dose your pa racing k member compare to the bmr turbo k member clearance? Have you heard anything on that subject?

konceptracin

Also what track do you go to in il?

PRAY HRD

iTrader: (119)

well josh built my kit around a bmr k'member and my engine is at the machine shop currently so i wont know for a bit yet how much it will need to be modified. kinda hoping not much.

i go to us41 morocco, in, no limit raceway.

looking forward to seeing your build thread!

98Z28CobraKiller

iTrader: (17)

You could put a GT4788 on a 600 ci mountain motor and max it out at 4k rpm and run 9's but its not the correct turbo for the application unless your application is pulling tree stumps out of the ground. The op wants the best combo, not a good enough combo. The fact that these turbos are making their best power under 330ish ci is why I wouldn't put it on a 408. My pt88 has been 8's with my 370ci motor at almost 3900#'s but I'll be the first to tell you that its not right for this combo. I'm looking to get into a GT5091 on my cubes and I'm only turning 7k rpm.

konceptracin

lmao.....

craig382ci

iTrader: (5)

When I spoke with a rep. at both Percision and Garrett. I told them what I had and what my goals was for my setup. Both place knowing what I have and that I was willing to sell the 4788 and go bigger. They said that they was no reason that the 4788 could not meet my goals of around 1100-1200 hp and no reason that it shouldn't hit high 8's in the 1/4.

That is if I got a good engine management system. Because I was going to have my harness repined for a 99 computer. And "that" they said would be my weakest link. But this was for my setup being mostly street. But when race season is on I will be going to some events to compete.

It just makes me wonder why 2 companies that sells the same stuff would not push for the sell for a bigger turbo. Help me understand this.

black98ws6ta

iTrader: (77)

PTE once rebuild a t4 88 for me like 5 times before we came to the mutual agreement that it was being over spun, pushed too hard, and failing. Alot of times there are fine lines to where a combo is happy or not and right or not and sometimes hard to get there without a long talk about a combination. Then there are people who have been there and done that and post up the results and nobody listens. I cant count how many times Dr turbo has posted that the 47-88 is too small for the larger ls crowd. I also posted my thoughts in this thread and I have a 47-88 on a 5.3l....which should be on the happier side of displacement for that turbo.