Gtx4202 or g42-1450 turbo? Wanting 700hp street car
 

Gents
Just after thoughts. Running 13b on e85.

IMO not going to be very "street" when you don't spool until 6k with that g42-1450.... I would look at the EFR9280, you may get there maxxing out a 9180....

I once tired to run a PTE7675 with a 0.96 open T4 on my 13b and the first time I took it out, I barely made any positive pressure under 5k. Took it off the next day.

Either turbo would make 700rwhp pretty easily. Any other details on the motor setup and use case?

Listen to Copeland.

Thanks guys. I have a street port with a t04z running 550hp on e85 at the wheels. I know the gtx42 has been around a while and interested in the results of the g42 as it's a new turbo. I see the BW is big in America but I would prefer to still to garett. Looks like it might be the gtx42 I may go with. But now the problem of which rear housing?

What manifold will you be using? T4, T6, V-band, etc? 1.5" 1.75" 2"?
Do you have a spool preference (what RPM?) or a peak power preference?

I'm open to opinion. A mate has a gtx42 that spools up at 3700 with 1.15 rear housing. Obviously the sooner the spool the better but I do want top end so I was thinking a 1.28 rear. What manifold would I use? I have a 3 1/2 inch exhaust

Top end power requires a large port regardless of turbo size. Using a large a/r, and huge turbo with a mismatched port leads to a smaller powerband.

I would use the EFR 9280 with the 1.05 and our cast EWG manifold, 4" exhaust, etc. This will make 700rwhp easy, and produce the fastest response possible.

The smaller GTX4294R will make 650rwhp, so a 4202 should do it no problem.

You'll want to pull your engine apart to do some machine work for 600+rwhp.

You'll definitely go through stock transmissions rather quickly.

CD009 or T56 Magnum are your reliable transmission options.

The engine is already ported. A stage two or also known large street port. Exhaust ports have been done also. I've had the standard gear box on it two years. I don't ram it through the gears so I guess that's why it's lasted so long with the to4z. But as you say over 600hp will be a different beast

Thank you. Are these options big money gear boxes?

Necessary. Wouldn't say "big money" since relatively it's cheap compared to other components on a reliable 600whp build.

Custom Driveshaft, Ford 8.8 Rear End, Heat exchangers, nice PTFE lines, huge FPR, custom exhaust manifold, custom downpipe, etc adds up quick.

A streetport will be helpful but you’ll need actual machine work. The engine needs clearancing/balancing at a minimum to make 600rwhp+ reliably. There are additional mods that will be beneficial as well, such as, studs/pins, oiling, etc.

As far as the transmission goes, you’ll see they fail exponentially faster/easier over 600rwhp. I went through 2 in a single weekend; street tires, not shifting out of a single gear, on an unprepped regular street.

With a genuine 700rwhp, you may be better off looking at an auto transmission like a modified Jatco, which is what you'll find most people in Australia are using at that power level. Manual transmission can be done but at considerably higher cost. Keep in mind that when you saw 700rwhp, if you are referring to Dyno Dynamics figure like most Australians do, then this is 10-20% lower than the figures US guys are more familiar with and quoted on this forum. In other words, when say 700rwhp, this more like 800rwhp in US language.

Who in the Gold Cost is doing the work?

What car is the engine in?

The car is a 2001 fd
The mechanic is in Brisbane and well known for his work.And no. Not mazfix. You are right I think more internal work first

Looks like the gtx4202r wins with a1.01 rear housing. Thanks for all the help

qeustion so the 350 /370z trans can hold more power more than the cosmo fd trans .

nobody is mounting an FD transmission behind an LS engine 😂

since this thread last ended Garrett released the G40-1150 and it would make for a much better 700 - 800 whp option, the 0.94 A/R divT4 turbine would be a good match, about the same swallowing capacity as the 1.01 A/R that was chosen in the prior posts.
​​​​​​.

the .94 not going to make 700hp let alone 800hp.

I did the testing and not even the 1.06 made 700RWHP. the 1.19 Got us to 700RWHP and by then we were just over 1:1 EMAP (34psi of back pressure at 30PSI of boost)

this was done on a 13B bridgeport

G40-1150 1.19 T4 in with twin scroll manifold great street setup

What engine speed were you seeing usable boost?

I’ve seen over 700 on a much smaller turbine :dunno: but seems like you’ve claimed this more than once

but just so we’re clear, the G40 1.06 A/R is higher flowing than an EFR9280 1.44 A/R

no offence, just because you didn’t do it doesn’t mean somebody else won’t

case in point, I’ve seen a S369SXE 1.01 A/R make 500-550 whp @ 30 psi on one car, yet on another posted on here it made 719 whp @ 30.5 psi.

Coincidently, the lower one was a BP, and the higher one was an extended large street/race port. And that S369 1.01 A/R is much lower flowing than what you’re claiming.

https://www.rx7club.com/single-turbo...19whp-1140159/


sometimes the details matter … and the OP posted 700 whp in the title, but stated 650 in a post. I was assuming on a dynodynamics though.

be interesting to know if he followed through and the result along with the details.

which the argument then becomes was he making the correct choice or not, I had meant to add these to that prior post and became distracted away from completing it:

https://cimg4.ibsrv.net/gimg/www.rx7...83d48031a.jpeg
.
https://cimg5.ibsrv.net/gimg/www.rx7...a92fcd278.jpeg
.

which the S369SXE results variation example I gave above, sort of matches up with the variation between these two as well:

https://www.rx7club.com/single-turbo...-dyno-1082295/

https://www.rx7club.com/single-turbo...04rwhp-949687/

.

You are just observing whatever other people are stating and drawing conclusions from this and then providing people with advice like its your own. Different brand dynes show different numbers and different dyno operators manipulate numbers to suit there own agenda. I do my own testing on my OWN dyno and do MY OWN BACK TO BACK testing.