The Central Hub for DSM Community and Information

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. This is where the DSM platform history is documented and archived. Log in to help us in our mission, and to remove most ads from the browsing experience.

4g63 cylinder head flow bench results

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

overdoseheroin

15+ Year Contributor
219
4
Dec 4, 2004
your mom, Minnesota
ok, i just flowbenched a stock 1g head and heres the results.

INTAKE

.100 lift : 78.44 cfm
.200 lift : 149.94 cfm
.300 lift : 204.33 cfm
.350 lift : 217.56 cfm
.400 lift : 224.91 cfm

EXHAUST

.100 lift : 84.42 cfm
.200 lift : 170.2 cfm
.300 lift : 204.88 cfm
.350 lift : 206.45 cfm

at .300 lift there was 100% intake-to-exhaust flow. my instrustor said his 8 second Fury with a 440 only has 80% intake to exhaust flow. now, after doing this flowbench, i went and did a MILD port job to the intake, all i did was take the lips off the inside of where the valve seat is and the burrs on the outside of the runners. i have a lot more to take out but heres the results from just taking the edges out.

STOCK INTAKE //////////////////////// MILD PORTED INTAKE

.100 lift : 78.44 cfm ////////////// .100 lift : 82.88
.200 lift : 149.94 cfm ///////////// .200 lift : 157.29
.300 lift : 204.33 cfm //////////// .300 lift : 221.97
.350 lift : 217.56 cfm //////////// .350 lift : 235.2
.400 lift : 224.91 cfm /////////// .400 lift : 244.02

it gained 20 more cfm at .400 lift with just smoothing out the edges. im going to finish things up on monday and post the results of the completely ported head. intake and exhaust.
 
Great job this is the kind of information these forums were meant for. Any before and after pic's would be good to show the extent of what you call clean up!
 
ill get all the other stuff up next week sometime after i finish everything up. BTW...all tesing was done at 28 pounds of pressure. thats what the industry standard. i could have pulled more numbers at a higher flow but 28 is the "standard".
 
Hm. Water seems odd. But I've not played with a flow bench, and don't know if your manometer might be inches of water. It should respond more quickly than mercury, I suppose.
 
you might be right, it may be mercury but we just refer to it as water. i dunno wats its all about, i just know how to use it. LOL
 
You must be logged in to view this image or video.



Start using it.

(please read the strict <a href=http://www.dsmtuners.com/forums/showthread.php?t=20033>guidelines for this highly technical forum</a>)
 
awsome!!:D glad to see another head porter out there! out of curiousity... are you going to unshroud the valves a little bit? are you planning on doing any combustion chamber work, or are you only working the bowls and runners?

Ray
 
slvrstingray said:
awsome!!:D glad to see another head porter out there! out of curiousity... are you going to unshroud the valves a little bit? are you planning on doing any combustion chamber work, or are you only working the bowls and runners?

Ray

im just gonna do the bowls and runners because its the only one i have. i dont wanna go to crazy and #### it up. once i get some more ones or pick up some junk ones ill start to #### with the combustion chamber a bit. but for now im not.
 
Defiant said:
Hm. Water seems odd. But I've not played with a flow bench, and don't know if your manometer might be inches of water. It should respond more quickly than mercury, I suppose.

Crazy business, while water is frequently mentioned it rarely is used because the column length if I'm not mistaken has to be over 400 inches long. So because it's denser Mercury is used in a 30 inch long tube and more accurate for you don't have to consider vapor pressure and temp to calculate. The measurments can be in inches, mm or cm depending on what is expected for the industry or the region. Hospitals have gone to electronics for measuring blood preassure but you can still see some of the folded units attached to the wall some with mercury and some without.

Cheers,
GTM
 
I am working on heads with overdoseheroin. I dont know whether the flowbench we are using is in water or mercury, it is a Superflow SF-600. So whatever that uses. My head actually flowed alittle more than overdoseheroin's on intake(like 241 at .400 if i remember right), and a little less on exhaust(like 185 or so). It was a amazingly good casting. The intake barely had any casting problems, the exhaust side had a few burrs, and there were lips under the seats on both sides. I am currently porting it. I'll post results when i have finished. Didn't bother to bring my sheet home. Oh and I am only doing port, bowl, and runner work. I haven't touched the chambers. I dont think overdoseheroin has either.
 
I am confused by the reference to the different lifts. I do understand how more lift can produce more flow, but………

Were different cams used to produce the different lift numbers?

*** admin edited - off topic ****

Anyway, an explanation to my original question would be appreciated. :laser:
 
LaserDad91 said:
I am confused by the reference to the different lifts. I do understand how more lift can produce more flow, but………

Were different cams used to produce the different lift numbers?
I don't think any cam is used. I would expect the valves are opened by a clamp, press or fixture and lift measured with a dial guage like in this picture.

You must be logged in to view this image or video.


The spec sheet says the pressure measurments are in inches of water, I think you can see the vertical column to the left of the dial indicator.

http://www.superflow.com/acrobat/SF600s.pdf

Steve
 
steve said:
I don't think any cam is used. I would expect the valves are opened by a clamp, press or fixture and lift measured with a dial guage like in this picture.

The spec sheet says the pressure measurments are in inches of water, I think you can see the vertical column to the left of the dial indicator.

http://www.superflow.com/acrobat/SF600s.pdf

Steve

Makes sense, thanks for the response. After thinking about it some, I figured this was the case, for bench marking flow at different constant lifts.

Wonder why some people cannot stay on topic?? (not referancing the person who I quoted above, but the other couplle of responses that added nothing) LOL. :laser:
 
I missed it the first time so took a look again at the PDF file. Indeed it says 180hp but then in paren it says 135kw per cylr. Using conversion of 1.341= 181.035 hp or a whopping 724 hp for the engine. I had to double check my calcs for I remember 755watts=1hp and it doesn't compute. Then you look at the electric demands where it says 240vac, 37A single phase... yeow that's equal to 11hp ??

Cheers,
GTM
 
GTM's numbers are correct, it's ~180HP per cylinder, which comes to a whopping 720HP. But the bench doesn't have to produce said horsepower, it just has to simulate the airflow required at those HP ranges. Doesn't take anywhere near as much juice to do that. Given an effecient enough design, I'd say 11HP could create 720HP worth of airflow.
 
ok, heres the final results. i was able to gain a few more cfm on the intake and ended up with 256cfm at .400 lift. the exhaust on the other hand....i cant figure out, i knife edged the divider, took out the area that surrounds the valve guide down to nothing and went as far as i could possibly go without hitting a water jacket and was only able to get a max of 219.6cfm at .400 lift. one of my friends doing the same head was able to pull 71% flow compared to my 68.5% wich averaged out to be close to 230 cfm. i duuno whats up but at least i gained some. th eother guy that posted above that is also doing a 4g63 head ended up with 2% less than i did but started out at a much lower cfm than i did also. maybe theres just not as much to gain on the exhaust side as i may have thought. ill post some pics up when i am completely done...(i just have the entire intake done and 2 exhaust ports done so far)
 
So with a little porting on the intake side you gained just over 2 lbs/min and going crazy on the exhuast side you got about 1lb/min..good info.

Nick
 
alright heres the flow numbers off my head, stock and ported. In cfm, at 28 inches of water (or whatever)

Stock
intake __________________________exhaust
.100- 80.7------------------------------.100- 70.3
.200- 160.3---------------------------- .200- 142.1
.300- 216.9-----------------------------.300- 185.34
.350- 228.7-----------------------------.350- 186.8
.400- 238.3-----------------------------.400- 188.2


Ported
intake----------------------------------Exhaust
.100- 84.4----------------------------.100- 75.7
.200- 157.7---------------------------.200- 155.9
.300- 217.7---------------------------.300- 197.1
.350- 235.3---------------------------.350- 201.5
.400- 247.1---------------------------.400- 200.0

I didn't go as crazy as the other guys because this is going on my car now, with almost no other mods. This was mostly cleanup, and just trying to smooth the transitions, plus a few other things like knife edge the dividers and take down the area above the guides. It didn't have a valve job though. I expect the low lift numbers to be better with a valve job.
 
I would be very interested to see the effect a good valve job would have on these numbers.

Given the flow disparity, perhaps the two of you could take casts of the ports to see what differences can be identified ? Is the cause a head casting difference that can't be replicated with a burr, or is it related to different approaches each of you took ?


Charles
 
sorry but i can't take casts of the heads. Mine is done and at the machine shop now. I also will not be able to flow it after a valve job. The only thing we noticed was that in stock form my head was a lot better casting on the intake although the exhaust seemed a little rough. The head had been beadblasted. The ridges under the seats were smaller than the other two stock heads we have around here, and the ports were noticably smoother on the intake side. As far as exhaust.....i have no idea. My instructor also said that all our heads(there are three of us that were porting) have outflowed all the other mitsu heads he has seen on the exhaust. The only explanation i can think of is that there might be some difference in nt and turbo heads(im just guessing, anybody know?) As far as overdose's results being better than mine on exhaust, he took more time and more out. I did mine in a few days just looking to improve flow, and the fact that my car has to go back together next week kept me from going as far. Other than that i really don't know why my exhaust flow was lower. Oh well, sorry i couldn't help more. Im happy with the results though. I can give an update in a week or two how it acts with the ported head but i have also pulled a lot of weight out so that may make it hard to tell how much the head makes a difference. Plus i am on mostly stock parts and im sure the head flow improvements would make more of a difference on something more modded.
 
Add Value - Be Respectful - No Trolling - No Misinformation - Participate Often!
Support Vendors who Support the DSM Community

Latest Classifieds

Back
Top