Street porting a 1.9 big valve head

[David McCollam]

Yesterday I was able to uncrate a box in my garage. I found it to contain a new 2.0L short block complete with flywheel and a new 2.0L cylinder head with cam bearings and valves. The 2.0L came with a sheet metal oil dam installed in the rear drain hole. I did not know that it was a factory item. What's something like this worth?

Thanks

[RallyBob]

Originally Posted by Gary I brought a RallyBob ported head to a "Performance" machine shop today to have cam bearings installed. The owner took one look at it and said "Holy Sh*t, look at this"... and proceeded to call everyone in the shop over to look at it. All were commenting on the level of detail and amount of work involved. He was very impressed and was truly admiring the work. He said it must have taken at least a month to do that porting. I explained the difference with porting the SBC heads and how excessive porting of the Opel exhaust ports could hurt performance. He said the difference between the two was evident. He also mentioned one 'trick' that he does is to use 80 grit for the intakes in order to provide a rough area to mix the fuel better. He ran his finger in the intake port, shook his head and said, "just like this one". Once again, the high level of Bob's skills and workmanship was validated by someone who is in the high performance game. Thanks Bob!

Gary, glad he liked my work. Hopefully you'll appreciate it more once it's on your car!

BTW, I used 36 grit sanding rolls on the intake ports of your head. I used 80 grit years ago, but I found that 36 grit was a noticeable improvement, especially when the engine is cold and running on the choke.

Bob

[RallyBob]

Originally Posted by timemachine I've enjoyed the dialogue between RallyeBob and Hiro. Now I have to backtrack and learn more so I can ask an intelligent question or two. Bob, we need to find you another shop, and a grunt or two to turn this stuff around for all your fans. Jim

Jim, I did find a shop, and finally after almost 4 weeks of trying managed to procure insurance for it. I was in a bind, the lease required liability insurance but I couldn't get any...something about me using a commercial space for personal work. There simply weren't any policies for this available, so I had to have a 'custom' policy made up for this. I got nine rejections from various insurance companies prior to getting this one.

The catch is that I truly can't do any outside work from this shop. It's for my use and my use only. If I do any 'outside' work I void the policy and therefore my lease is then in jeopardy of being dropped.

I had considered opening it up as a business but the costs of running a small business in this state are outrageous. C'est la vie.

Bob

PS, happy birthday BTW!

[cherokee]

Originally Posted by RallyBob The catch is that I truly can't do any outside work from this shop. It's for my use and my use only. If I do any 'outside' work I void the policy and therefore my lease is then in jeopardy of being dropped. I had considered opening it up as a business but the costs of running a small business in this state are outrageous. C'est la vie.

Go south!!! The further south you go the better it gets, no cold winders and a LONG riding season. I bet I am not the only one that was wishing for some RallyBob porting and such to be offered again.

[GTJIM]

Originally Posted by RallyBob The catch is that I truly can't do any outside work from this shop. It's for my use and my use only. If I do any 'outside' work I void the policy and therefore my lease is then in jeopardy of being dropped. Bob

Seems to me that you will have to do HEAPS of work for yourself and throw LOTS of it into the skip ... then sell the scrap ... for $100 a pound!

[RallyBob]

Originally Posted by GTJIM Seems to me that you will have to do HEAPS of work for yourself and throw LOTS of it into the skip ... then sell the scrap ... for $100 a pound!

Well, you got the first part right! I have such a huge backlog of personal work, it will be nice concentrating on my stuff only for once. And I refuse to put a computer or phone in the shop (even though there's an office), less distractions for me! I spend an inordinate amount of time on this site, and documenting projects step-by-step consumes even more of my time which should be spent either building cars or racing them.

I figured that if I don't do this now, then there's no way for me to work on my cars anymore as I wouldn't have space for cars or tools otherwise. If that was the case then it would be time to get out of cars altogether, and find another hobby that requires less storage space.

Bob

[GTJIM]

I know exactly where you are coming from, Bob
Just spent two weeks solid doing work for myself - locked the workshop door and threw away the cell phone to get a clear run at my jobs!

[namba209]

Originally Posted by RallyBob Well, you got the first part right! I have such a huge backlog of personal work, it will be nice concentrating on my stuff only for once. And I refuse to put a computer or phone in the shop (even though there's an office), less distractions for me! I spend an inordinate amount of time on this site, and documenting projects step-by-step consumes even more of my time which should be spent either building cars or racing them. I figured that if I don't do this now, then there's no way for me to work on my cars anymore as I wouldn't have space for cars or tools otherwise. If that was the case then it would be time to get out of cars altogether, and find another hobby that requires less storage space. Bob

Methinks it's time for you to do some of your stuff, Bob. You're sure as hell(o) entitled after all the tech support we've gleaned from you over the years. One thing though, there's no such thing as a hobby that doesn't require space. Personal experience talking here. Cars, model boats, motorcycles, golf, and dogs, I've got 2 storage facilities and Margaret has one, plus we have the garage, barn and overhead storage above it, and we still need more room.

[CDN OpelNut]

Originally Posted by David McCollam Yesterday I was able to uncrate a box in my garage. I found it to contain a new 2.0L short block complete with flywheel and a new 2.0L cylinder head with cam bearings and valves. The 2.0L came with a sheet metal oil dam installed in the rear drain hole. I did not know that it was a factory item. What's something like this worth? Thanks

OK, so how does one have something like this and not know it? I could use some surprises like this!

[RallyBob]

Originally Posted by Kadett-o-Maniac Hello! Is somebody here, who has a flow diagram with 1.88" Manley Race Flo intake Valve on a 2,4 street or race performed head? Thanks and regards from Ronny

Ronny, I finally found that old flow chart (from September 1996!). The problem is, the head is a 2.2 head, and not a 2.4 head, so the results will be a little bit different. I noticed than the low lift airflow is rather good on this head, but I cannot remember exactly what I did to the head. I only have the valve sizes listed and the customer's name. I seem to recall it was for road use but he may have raced autocross (slalom) with it as well.

Intake port - 1.88" S.I. Competition valves #1259E

.100" - 40 cfm
.150" - 57 cfm
.200" - 74 cfm
.250" - 89 cfm
.300" - 101 cfm
.350" - 114 cfm
.400" - 126 cfm
.425" - 131.5 cfm
.450" - 135.5 cfm
.475" - 138.5 cfm
.500" - 142 cfm
.525" - 143 cfm
.550" - 144 cfm

Exhaust port - 1.60" S.I. Competition valves #1202E

.100" - 36 cfm
.150" - 51.5 cfm
.200" - 64 cfm
.250" - 74 cfm
.300" - 81 cfm
.350" - 88 cfm
.400" - 93 cfm
.425" - 103.5 cfm
.450" - 107.5 cfm
.475" - 110 cfm
.500" - 111 cfm
.525" - 112.5 cfm
.550" - 114 cfm

In retrospect, I am very surprised at how well the exhaust ports flowed for a 2.2 head. And I did find that I noted on the flow chart that the maximum valve lift was .480"/ 12.19 mm. But overall it did very well.

Bob

PS, happy (late) birthday Ronny!

[Kadett-o-Maniac]

Hello Bob!

Ok, thanks a lot for this flow chart, because we will order exactly these Si valves in 1.88" and 1.60" in the next time and after porting the in- and outlet, we will also use a flow bench for the results of our work, if it is possible, i will show you here on this thread!

Right, we will use a 2,4L head, our "God of porting tuner" here in Germany uses also an flow bench and he selled him on ebay:

Sportzylinderkopf f. 2,4 Ltr. Opel CIH /Kadett C/ bei eBay.de: Antrieb, Motor Getriebe (endet 11.11.07 21:00:00 MEZ)

He promised 221 HP with a intake port flow from 198 cfm,
but he uses 45mm intake valves, we will use 47,75mm, i think
(hope) maybe we will come to 230 cfm, we will see!

And thanks for congratulations to my birthday...

Best regards

[Hiro]

Originally Posted by Kadett-o-Maniac Hello Bob! Ok, thanks a lot for this flow chart, because we will order exactly these Si valves in 1.88" and 1.60" in the next time and after porting the in- and outlet, we will also use a flow bench for the results of our work, if it is possible, i will show you here on this thread! Right, we will use a 2,4L head, our "God of porting tuner" here in Germany uses also an flow bench and he selled him on ebay: Sportzylinderkopf f. 2,4 Ltr. Opel CIH /Kadett C/ bei eBay.de: Antrieb, Motor Getriebe (endet 11.11.07 21:00:00 MEZ) He promised 221 HP with a intake port flow from 198 cfm, but he uses 45mm intake valves, we will use 47,75mm, i think (hope) maybe we will come to 230 cfm, we will see! And thanks for congratulations to my birthday... Best regards

198cfm on a SF600E,
Bob how much would this be on a SF110?
Hiro

[RallyBob]

Originally Posted by Hiro 198cfm on a SF600E, Bob how much would this be on a SF110? Hiro

If he measured at 28", then it is 118.5 cfm (conversion number is 1.67). If he measured at 25", then it is 128.5 cfm (conversion number is 1.54).

Bob

[GTJIM]

Just remember that bigger valves and high, 'dry', air flow cfms do not translate into automatic increases in 'wet' flow (when fuel is introduced to the mix ..) and actual horsepower. The port shape and valve shrouding have a very big influence. Also max air flow (and port/valve size) may increase high rev power but chop the guts out of the torque curve at lower revs ....

Of course - if you are just competing for the big air flow numbers ... and not for a usable head ... keep on grinding!

[RallyBob]

Originally Posted by GTJIM Just remember that bigger valves and high, 'dry', air flow cfms do not translate into automatic increases in 'wet' flow (when fuel is introduced to the mix ..) and actual horsepower. The port shape and valve shrouding have a very big influence. Also max air flow (and port/valve size) may increase high rev power but chop the guts out of the torque curve at lower revs .... Of course - if you are just competing for the big air flow numbers ... and not for a usable head ... keep on grinding!

I agree Jim. More is not always better. The 1.9 heads are particularly notable in this regard. I can hit 138 cfm with those by 'hogging' them out, but they don't make as much power as a properly ported head with 125+/- cfm. But even that number didn't happen overnight, it was after many piles of cast iron dust were made and countless tests in the real world. Which is why I shy away from getting into port size specifics...too many unknown variables.

The flow bench is a tool, just like a dyno is a tool. Nothing more. The only way to know what the final outcome will be is to test the heads on the bench, test them on the dyno, and then test them in their environment (street or race track depending on the intent).

Bob

[Hiro]

Originally Posted by RallyBob If he measured at 28", then it is 118.5 cfm (conversion number is 1.67). If he measured at 25", then it is 128.5 cfm (conversion number is 1.54). Bob

Thanks Bob,
Gross advertized cfm may look impressive,
But of course depends upon experimental conditions!

[Hiro]

Originally Posted by RallyBob Ronny, I finally found that old flow chart (from September 1996!). The problem is, the head is a 2.2 head, and not a 2.4 head, so the results will be a little bit different. I noticed than the low lift airflow is rather good on this head, but I cannot remember exactly what I did to the head. I only have the valve sizes listed and the customer's name. I seem to recall it was for road use but he may have raced autocross (slalom) with it as well. Intake port - 1.88" S.I. Competition valves #1259E .100" - 40 cfm .150" - 57 cfm .200" - 74 cfm .250" - 89 cfm .300" - 101 cfm .350" - 114 cfm .400" - 126 cfm .425" - 131.5 cfm .450" - 135.5 cfm .475" - 138.5 cfm .500" - 142 cfm .525" - 143 cfm .550" - 144 cfm Exhaust port - 1.60" S.I. Competition valves #1202E .100" - 36 cfm .150" - 51.5 cfm .200" - 64 cfm .250" - 74 cfm .300" - 81 cfm .350" - 88 cfm .400" - 93 cfm .425" - 103.5 cfm .450" - 107.5 cfm .475" - 110 cfm .500" - 111 cfm .525" - 112.5 cfm .550" - 114 cfm In retrospect, I am very surprised at how well the exhaust ports flowed for a 2.2 head. And I did find that I noted on the flow chart that the maximum valve lift was .480"/ 12.19 mm. But overall it did very well. Bob PS, happy (late) birthday Ronny!

Here is the plot,
Sorry for the delay!
Exhaust shows a double-hump curve,
Any clue about this Bob?
Hiro

[GoinManta]

The first part of this article was great.. but trying to print it and get the essense of it to the shop wasnt as easy. So I have converted it into an article format in PDF. Let me know if any corrections are needed.

Should be great for giving to any good machine shop to get your head done.

Charles