Hey guys, one of my fellow MechEng friends were going through some engine layouts for a project. He noticed some things everyone should atleast be aware of. The Ralliart engine is a 4G63 with some modifications. Looking at the details of that engine and the 4G69 info that he could gather, he came to several conclusions.

1. Yes, the low-compression layout does make for good boost levels.
2. Higher levels of boost (that may not even require race gas) may break the rods.
3. The cylinder walls a very thin. The block should be sleaved if heavy boost is being considered.

Again, this is purely speculation. He hasn't done any tests, so just keep this in mind and have fun tuning.

 

good inf, where did u get the engine layout?

 

Yeah, I'd like to know too....also, what are you calling "high boost"? That notwithstanding, the rods SHOULD be replace if goin' for high boost anyways but I had no idea that the cylinder walls were so thin.

 

Here at Texas A&M we have access to all kinds of blue prints. I can't really specify high boost, because 1 psi on one turbo is different from 1 psi on another turbo. At 250-300 whp I would raise an eyebrow. That is our guess. Only testing will tell. The part of the cylinder wall that is adjacent to another cylinder is very thin. Increased pressure from more airflow leads to more heat. This could lead to some major problems if cooling and engine re-enforcement aren't considered.

My biggest point is:
This engine is very friendly to small amounts of boost. But beyond 200 whp, there are alot of factors that need to be considered.

This engine isn't as easy to boost as some other engines on the market. Honda's K20 series and Nissan's VQ are examples of two engines that can handle alot of boost without heavy modification.

The Ralliart is very young, and I would love nothing more than to see you guys prove me wrong. I have yet to purchase my vehicle, but the time is approaching.

 

One thing I forgot to add, the cylinder walls are thin because Mitsu wanted a light block with (relative) high displacement. They simply bore'd till they could bore no more. America for example, will just get a bigger block. This adds lots of weight.

Mitsu saved alot of weight going their route, but made a hurdle for boost freaks. I think this engine has a lot of potential without boost.

My proposal:
Start: 145 whp

Add:
Intake
Fully exaust w/ headers
Forged rods and pistons (11.3:1 compression)
Full engine management w/ 3D fuel mapping & MIVEC control
Porting & Polishing (not much porting can be done due to narrow bore)
MIVEC compatable cams adjusted for new setup
1 tank of 91 octane gas

Finish: 200+ whp

Believe me, it can be done. The three stages on MIVEC are the iceing on the cake.

 

All 4g6x engines are related to one another. Also, the 4g69 may be the last engine that Mitsu will create for this block family.

The same for the 4g9x, 4g1x, 6a1x, and 6g7x. There are within the engine block family.

 

Hey MitsuRalliArt, how much does that set up you posted cost? And what's the 145 HP you talk about starting with? All my info says the Ralliart has 162 to start with.......what would your set up raise that to?

 

145 is the whp (wheel horsepower) 162 is what mitsu rated the engine at the crank.

 

anyone know if PR Turbo Tech had to do any sleaving or anything? He has over 20 PSI on his ralliart (23 i think). I know he had forged pistons and better rods made up, but I dunno about any additional reenfocement, but I think he said he was well over 400 HP and running a 1/4 in 11.1sec.

 

Stock sleaves 23psi with a GT28RS GARRETT TURBO electromotive engine management system,turbosmart intelligent boost controler,900cfm yonaka intercooler,tial 38mm hibrid wastegate,tial 50mm blow off,860cc injectors,2 fuel pumps,custom made fuel rail, BEGI fuel press regulator, ROSS 8-5-1 forged pistons,crowell rods,greddy evo 2 exaust system,greddy egt ,air fuel gauge warning,clutch masters stage iv clutch and custom made by clutchmasters a aluminum fly wheel,sparco monza racing seats,quaife LSD,RRM motor mounts,450 wheel hp at 23 psi boost,and proud to be made in the island of puerto rico by turbo tech p.r.

 

if any one interested my ralliart is going to be in the front cover and the complete story inside icluding a poster doing a awsome burn out, of the mayor p.r. racing magazine it call supercompacto puerto rico it will be realesed in the bigining of august to obtain a copy you can e-mail to this adress supercompacto@hotmail.com the cost will be $4.99+s/h.thanks turbo tech p.r.

 

will it be printed in english or spanish? regardless, put me down for a copy =]

 

Saludos Malving...!

Esto te quedó bien patriota...Jejejjeje.. ",and proud to be made in the island of puerto rico by turbo tech p.r. " We'll if Turbo Tech is pushing 400 WHP I'm more than happy to know the stock block is up to the task..! Let's se how many STI's can push that amount of power without pushing a Rod through the block or flexing the crank.. And one important note 400whp from SOHC NOT DOCH..

T-rush

 

Saludos tunder-rush.

 

so basicly what mitsuralliart said was bull?