Well I tore the teeth off my timing belt upon start up yesterday -_- , so being an interference motor I most likely damaged a few valves. In any case while it's down and the head is off I'm gonna get it P&P. I pray I didn't damage any cylinders!! Anyways my question is will I need to get my RA tuned with a stage 2 P&P?

 

there's probably not any damage if it was on start up...mine failed at highway speeds, but not in MIVEC, and it was OK...i pulled the head anyway, but didn't bother to port it...isn't polishing supposed to be worse for airflow?

 

With polishing there are various schools of thought. I've read that it only makes the consumer think that they are spending good money and that it does nothing. I have read that the trick is to polish one side of the port only, there by allowing the air on that side to have a greater speed and generate swirl and tumble into the cylinder, which helps combustion and cylinder filling at low engine speeds.

I have most been influenced by 2 projects done by Larkin Auto Developments, where the guy ported and polished the head, added a short ram intake and aftermarket exhaust, adjusted the vernier on the cam (it came stock on the car because French auto makers are cool like that) the 1.6L went fromt 120 to 160bhp, the 2.0L went from 167 - 200 bhp. No ECU programming was done.

The 1.6 was either a Peugeot 106 or a Citroen Saxo. The 2.0 was a Peugeot 306 Rallye.

When I ported the head on a previous car, I did the area behind the valve seats till it was flush with the seat. I got rid of the hump in the port, and opened the port to the gasket. Then I wet sanded the entire port till it was shiny but nothing close to a mirror finish, since I had not the skill or patience for that.

The improvements were especially noticeable from mid range to top end (3-6k).

If I do another head, I would polish it. The Integra Type R's supposedly had a mirror finish from the factory. Never seen one, that's what the reporter driving it said on tv.

 

Shadow , I had my head fully p&p from the intake and exhaust ports all the way to the dish. It was all rebuilt as well with bronze bearings too. The gains are definitely in the mid to top end range, at wot it just roars. A tune isn't required but it will only help.

2006RA I have heard of the pr guys getting an aftermarket cam gear and advancing the timing 8-12 degrees but I haven't been able to talk to one of them that did it personally. They have reported around 10whp with the mod though. Which if it's true isn't bad for 200 bucks. Edwin would be the guy to talk to maybe he will see this and throw some pr knowledge this way. Finding an English speaking PR 4g69 forum would probably be a god send if it exists

 

hey guys. so I have a 4g69 eclipse and am doing a rebuild as well. I'm curious would it be cheaper to buy rrm's stage two head, or to have mine port and polished + valve job + resurface. I'm not sure how the ralliart is but the eclipse is all low end torque, so the 3k-6k range would be a huge improvement for me. also to those of you who have done the port and polish already, did you both do the intake manifold also? how much did everything run you?


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Sorry to revive an old thread, but I have the exact same questions as sa215ol for my 06 4G69 ralliart

1) buy RRM's p&p head stage, or have mine ported/polished, decked/lapped, valves done by a local machinist? how much time and care does RRM take in machining their head stages for the 4G69? can it definitely handle 400hp like they say? can someone who has installed this provide a review and the types of gains attributed to this?

2) if i get the head stage p&p'd, should I get their intake manifold too, and will they port match? do you want to port match?


I wish I had more options... I've entertained the prospect of just doing a full EVO head swap, but after a bit of research I've learned this can be an expensive en-devour - far more in terms of cost than using RRM's head and IM (despite being able to take advantage of far more options for turbo/intake manifolds, cams etc...)

 

1. get a quote from a machinist...upper gasket kit (MD979393) is around $200 from mitsubishi...3rd party is is $107 on amazon. so depending on how much they charge for the machine work, it could be more cost effective than RRM's head, plus if you're having an engine built, you don't need the convenience of a spare head to swap, plus you can have your block and stock head decked at the same time...

as an example, it cost me $280 taxes included to have mine decked, dipped, new valve guides, valves ground and re-seated, and lapped. not sure how much porting would add but i doubt it would be more than $5-600 total, plus you don't have to pay shipping.


2. same answer applies to the intake manifold, and yeah port matching is not a bad idea.

 

Thanks again Cranswick

I'll shop around and see what my options are locally.

As for the IM, RRM claims theirs is polished as well, but I was reading that this is actually a bad idea...?

 

I've never seen a definitive one-size-fits-all approach to achieving best intake flow. Some gurus swear by mirror polishing and knife edges, other just clean up excessive flash, some port match and some don't, some hog out and some don't, and some use fancy multi-angle valve seat jobs.

As fluid dynamicists know, managing airflow behaviour is still close to a black art, and each intake system design needs its own flow bench R&D to realize performance improvements, or to determine whether any are even possible.

I dunno, unless flow improvement can be shown with a results print-out from RRM, maybe its best to get your intake system re-worked by a local expert with a flow bench? There must be some serious speed shops near you.

 

local experts are far and few between where i live unfortunately. it'd be a 5 hour journey to anywhere truly capable, in my mind, of achieving strong, measurable gains in performance where the IM is concerned.

i've requested to see data from RRM although i doubt I'm going to get anything. my goal is 300hp which i think is still achievable even without a perfectly crafted intake manifold, so I don't need to go to any extremes, although it is odd that a lot of users are saying a mirror-polish finish is a bad idea, yet RRM actually does this on their IMs...

 

lol rrm doesn't mirror polish at all. I got their intake manifold many years ago , it was ported about 2 inches in , (not to mention the IM i received was 10x as dirty as the core i sent back , the camber was brown from the egr valve ) and had a crappy powder coating that is flaking off as I write this. When i got my head fully p&p , 5 angle valve job ,with bronze bearings I had them re p&p the RRM IM. They got in about 6 inches and smoothed out all of the casting lines in the runners and in the intake chamber, and port matched it to the eclipse gt TB. At WOT the gains are noticeable but but below 3k its the same as before.

I'm really trying to make her more quiet, I think I'm going to look for an oem cat or a big highflow one , the 22'' magna flow resonator helps but she is still very loud.

 

Lanzer, that is exactly the kind of experienced feedback we need

Yeah, for offroad use I'm wanting to bypass just the catcon, and don't know much about it. Are you at all familiar with those exhaust diverters?

 

Yea Ive seen them, I've been running catless for 8 years lol .....


O and Don i have an extra oem IM I'll sell you so u will have less down time. PM me if your interested

 

thanks for the feedback, i guess now i know to more than likely avoid RRM for this.

my car is catless too with the RRM headers and magna catback - it's very loud, although this winter the vehicle is off the road where I'll be rebuilding the motor and adding a turbo kit...hopefully the end result of that will be a slightly quieter ride.

i have a brand new, never used weld-on cat piece from RRM that I don't intend on installing - would you like to buy it? Looks like this: http://roadracemotorsports.com/store..._9836_4804.jpg

thank you for the offer on the IM but the vehicle is parked for the winter (i bought a cheap truck).

i'm going to visit a few local automotive machinists and see what my options are

 

Thanks for the offer but I think I'm going to install a big oem like magnaflow cat, not the racing highflow one, the sound is just a bit to loud for me.