Port Map on 2.0 and 2.0 mods

[Germansaleen]

Happy New Year :thumbsup: to all here at S&F

i just start porting my 2.0 liter block and i got most of my information here at the board from wrenchin,t rex,mach351,jay smith and all the other well known guys here on S&F from older thread's.
THANK'S FOR THAT !! to you all:thumbsup:

i am searching for the stock portmap or spects from an 1990 or similar 2.0 150 to compare

i have a 2.5 slow dog and a well running 2.0 from last year ,the 2.0 has allreaddy horizontal 5 petal reeds ,cross drilled 96770 intake,wh 29 carbs, short 41941 tuner,no can.

it looks to me that the block and piston was decked 0.050 before ? or has little portwork ? and chestwork already done from the previous owner ,to almost an 200 2.5 porting.
take a look at my portmap !


i will stick for 2011 with my high reving little one, the 2.5 is a slow dog compared to my 2.0 liter on my hull.

will rise the exhaust to 1.550 and little more chest cut to get the gas transfered better and more downwards,leave the transfer ports as they are and open up the exhaust and gasket match the ports in the two piece exhaust plate.
have also to drill the mid with 5 1/2inch holes above the cavitation plate like mod vp mid ?. forgot to mention send heads to jay to get cut to 150/155 psi(we have 100 octane V power pump gas here) ,intake/reed cages ported and lapped ,td reeds and 1 inch spacer. (hard to get for 5 petal) and last the velocity stacks for the bling"
the phantom p20 hull less engine is around 800lbs
michael

[wrechin2]

Happy New Year!!!!

Most 2L exhaust porting will be around 1.625 to 1.650 is the normal for either a verticle or horizontal engine. They use the same sleeves and sleeves come with the ports already cut in them. I have measures a lot of the verticle engines prior to porting and the above seem to be the adverage. The transfers are usually around 2.120. If the port map you posted is of the 2L the porting looks normal and untouched. I have a few untoughed I will measure in a little while and post. On the 2.5 you may have a very low ported engine, if it is a idle relief engine, it will have porting around 1.700 and a "O" ring 150 will be around 1.740. A 175 EFI is usually around 1.650 and then a 200 up to 95 will have 1.610 and then a 96-00 will have 1.595. Then you get into the "O" ring stuff. With mercury you may have one that is not adverage. My avitar is a 1.665 2L I built. I never raised the porting on it and it was a brute on bottom but hit a brick wall at 6K. You may have a very low ported 2.5 or a very tired one. Good luck on your project!

[Germansaleen]

thank's wrechin
that will bring light in to my dark

yup.. the map is from my 2.0 and it has the idle relief

anyway i have to port it, i like the sst120 spects 1.545 and 2.040 but thats on a lightweight hull with no drag at all and it works well in that class,have seen a couple of sst120 vids on youtube how fast they are on plane.
i need more torque to get on plane.

would be interesting to know if somebody had an 2.0 sst120 porting on a havier boat or a bassboat in the 1100to1200lbs range and how it worked out.

will post the progress and results if the project is done and in the water:smiletest:

[fyremanbil]

We run many SST120 engines, converted to right hand rotation, on ModVP type hulls with similar weight to yours. They work fine but don't expect great low RPM performance. I have an engine similar to the one you are building ported to 1.550 and 2.100. Peak power occurs at about 7400 RPM. If I build another, I'd cut less out of the exhaust chest. The stock SST120 engines are regularly run above 8000 RPM with stock exhaust chest.

[wrechin2]

Sorry I forgot to get the specs off the blocks last night. I have to crate a block up to ship back to the customer in the am and I will get the specs off it and post it. I have 5 or 6 blocks myself in storage and I one on the shelf in the shop. I will measure it as well in the AM.

I do a lot of 2l for heavier bass boats. I run a combination on the 2L with 1.595 exhaust and stock transfers, 28.5 CC heads, wh-29's with .068's, and keep the verticle front. They work out very well and very stong on bottom and midrange. Here is one that I did on a Ranger boat. We gained just a little over 8 MPH GPS with the modifications and decreased the hole shot by 5 seconds as per the customer. Just my .02

Ranger with a modified 2L running
http://www.youtube.com/watch?v=jDupz_Kcsdo&feature=mfu_in_order&list=UL (http://www.youtube.com/watch?v=jDupz_Kcsdo&feature=mfu_in_order&list=UL)

[Germansaleen]

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If I build another, I'd cut less out of the exhaust chest. The stock SST120 engines are regularly run above 8000 RPM with stock exhaust chest. <!-- END TEMPLATE: newreply_reviewbit --><!-- BEGIN TEMPLATE: newreply_reviewbit -->fyremanbil
thanks for the information,i will cut the exhaust chest just a little only to get the gasses more in an downward motion and keep backpressure as much as possible for low end.


wrechin2

Sorry I forgot to get the specs off the blocks last night


Thank's very much wrechin ..but take your time !!
how did your chest cut work out on the 2.0 second picture(found in an older tread), i will go little less like the first picture 2.0 chest, just a little bit cleaner.
sometimes less portwork is more :smiletest: .

would be very interesting to se a portmap of the last 2.0 200hp carbed offshore oversea version ,what is around here some often on boats and in offers.its a racing block ,carbed and so on. i can get one here lokal right now for around 3000$ rebuild ,but who knows whats inside.
thats wy i do the rebuild most by my self :smiletest:

here are two portmaps of sst120 and sst200 if somebody needs

[Germansaleen]

some pics of the 2.0 offshore 200HP carbed version

[wrechin2]

That 2L overseas is probably a behind the liner 2L like the EFI version is.

I never ran that block. I cut it and was my first attempt at a tuber engine and made a mess out of it. I used it to figure out the angles to mill in the slots for the tubes and to do finger ports. I have ran blocks very similiar to that with great bottom end. I will direct the exhaust like a Pro max (or 96-up 200) on the one I am buiding now. You are right sometimes less is better.:thumbsup:

I got the port specs off of 2 blocks Only thing that seems average is the booster.:mad:

Build date Exhaust Transfer Booster
1-23-84 1.615 2.110 2.200
2-05-87 1.630 2.130 2.200

Here is what I cut the 2L block all up for.

http://www.screamandfly.com/showthread.php?227851-Capt.Insane-o-need-your-opinioin (http://www.screamandfly.com/showthread.php?227851-Capt.Insane-o-need-your-opinioin)!!!!

Hope this helps!!!

[Germansaleen]

Hope this helps!!! <!-- BEGIN TEMPLATE: ad_showthread_firstpost_sig --><!-- END TEMPLATE: ad_showthread_firstpost_sig -->

oh yes !!

i have the same stock porting as your 87 now ,thought my 2.0 was ported a little because it was running so well.
my 00/04/90 1.630 2.130 2.200
your 2-05-87 1.630 2.130 2.200

the merc engineers do change port maps like i my underwear:smiletest:
every day is a different one, maybee alcohol involved or they smoke pot at lunchbreak ?:smiletest:


very nice job on the tuber, i like what you are doing and most.... i like that you chare the "Racing Secrets" with others :thumbsup:thats what makes this board running.

[wrechin2]

You think it runs well now, do a little work to it and you would be surprised. It won't make to brute power of the 2.5L but will run well and take some abuse. I like them!

Merc engineers...... I had a 2L I lost a lot of brain cells on one I was building for a guy. It was a powerhead replacement that was produced in 1994 to replace a 88 XR2. It was a verticle engine. The exhaust porting on it was staggard by .005. It started out at 1.640 and went to 1.615!!! I was trying to figure out what they were trying to accomplish. Hell with all the porting I have seen over the years, they may had several liners left over and just used them on this engine. Who knows, so I said screw it and I then ported it to to 1.595 and was done with it. Matter of fact it was the one that was on the Ranger in the video above.

[ThunderHawk]

Hello

I found this thread when looking for info on porting a 2,0. I have a 150 from 1990 with back pressure relief and exhaust tuner from Bob's Machine Shop, Boyesen reeds, velocity stacks and XR2 intake and flywheel. Advance is set to 24 degrees. Oil injection and all unwanted electronics are removed. I still hit a wall at 5600 rpm, so it was time to check the port timing.

I went for the 1.595 exhaust port, some improvement on the chest and no mods on the transfers. I'm also going to raise the compression closer to 145 PSI.

The questions are:
Should I rejet my WMH-7 carbs from .062 to something in the .066 - .068 range?
Does the 16 x 3/8" holes in the rig relief enough pressure? (Totals at 1 3/4" sq.in.)
How big a hole should the washers have that I use for replacing the thermostats in the heads?

Thanks for a superb forum and greetings from Finland.

Thomas