How much do i cut from my v-4 tuner

[sixabove]

1996 115 evinrude to drag race on a 1000# weigh in.

[Bill Gohr]

should be 7 in from the bottom of the adaptor plate. See if you can find a 1977 140 (only) it has a better tuner assy it's the only engine that had it. If you need one call Dick at Dicks marine. 847-587-2102

[sixabove]

i have seen quincy pipes with the holes at the base. supposedly they helped with low end torque. should i leave them or plug them?

whats the difference in the 77 140 tuner? bell shape? length?

I have a early 70's 135 tuner. will it work any better than the 115 tuner in the pic?

[Bill Gohr]

The 77 tuner is just slightly different than cutting yours as I said. It has a slightly wider bell to it. The older tuner will not even bolt up to your engine.

[Laker]

Where is the power gained by doing this Mod? Where is it lost? Does it come off the bottom? I melted 2 tuners off my 77... Found them laying in the gearcase.

[Laker]

Bill
Dicks Marine doesnt have any....
Any other Ideas?

[Bill Gohr]

He does tell him to go up on the roof and it's a silver v-4 center section, did you tell him I told you he had it? he doesn't know

[sixabove]

guess ill wip out the old sawzs all and git to hakin

or will a 8" cut give me similar performance?

[Bill Gohr]

Over there today, he doesn't want to go up there and get it. It's there though. All you can do is cut it off. 7" is what we always cut them to. Thats how long the 77 is

[Laker]

Ya bill that Is what I got from dick also
They Didnt want to mess with it........:mad:
Wish I took pics of my last one so I could have it redone.
How much better do you think it is over a stocker cut to 7-8 inches?

[Rickracer]

Bill gave me the same tuner advise 10 years ago on my '76 135. (not changing it, just cutting it)I did reeds, compression increase, and the tuner all at the same time, and the difference was absolutely amazing.

[Laker]

Hi Rick
That makes sense because my 77 (Factory cut tuner) was quite a bit stronger than any other V4 (Or I6 for that matter) only real difference is the tuner and my 77 heads were Very tight.

[sixabove]

HAVE SEEN STOCK 135'S WITH 150LBS

IF I CUT MY STOCK HEADS (125LBS) .030 THAT SHOULD GIT ME PRETTY CLOSE TO THAT FIGURE.

MY ONLY WORRY IS A LEAN RUNNING CONDITION.

HOW MUCH SHOULD I UP THE JETS TO START.

SHOULD I USE THE NEWER (96) 115 CARBS WITH THE EXTRA TUBE IN THE THROAT OR THE OLDER (1990) WITHOUT .

I KNOW THEY ARE ONLY 1 5/16 BUT THE 1 3/8 ARE GOING FOR THE PRICE OF GOLD.

WHO HAS THE BEST DEAL ON EXHAUST STUFFING BLOCKS?

[sixabove]

WILL I GAIN MUCH BY RELIEVING THE EXHAUST IN THE MID SECTION?

MAYBE A 2" HOLE ON EACH SIDE AT THE LOWEST POINT ON THE MID SECTION.

LOUD IS NOT A PROBLEM!

[Rickracer]

I wouldn't necessarily recommend it, but it worked for me, and it was loud, especially at
7000+.
:cool:

[Bill Gohr]

Look for 73 heads they are the best, 317848,849 cutting your stock aren't worth cutting. 78 and 79 V-4 carbs are the best. If you're going to relieve the exhaust do it in the gearcase not the center center section. You usually won't see a gain in performance unless you're turning it over 7000

[Laker]

Bill
I was wondering, Is any of the 125 stuff better? Heard a rumor that their might be a 125 head that worked better than the 73 135 head. How much tighter were the GP heads also.
Thanks
Chris

[Bill Gohr]

I've had people tell me they thought that the 125 heads were better but I've never seen it. The GP heads, the latest ones (KR15M) were modified versions of 135's. The 135's cut down and fitted to the motor work the same.

[Laker]

Bill I thought I saw 125 heads on Jeff Bakers latest motor?

Charlie The production motor Heads that I know about are different the later you go. Like Bill said the 73s are the best, then 74-76 are about the same (slightly looser) then the 77 (looser again) the 78-79 are the tightest heads that have coil mounts. If your gonna run the 73s you will want either want to run 77 type Ignition or make up coil mounting brackets.

[sixabove]

this will be strictly a drag motor no skiing behind this baby.

i have a set of modified 135 heads that produce 215lbs but they need coil brackets.

the class i run is pump gas only 101 octane no boosters

something tells me that thick head gaskets arent going to bring the compression down enough to run pump gas.

and if i retarded the timing that much this motors IQ is going to drop below 40.

what is the main problem in cutting the late model heads, say .030?

most people i talk to dont recomend over 145lbs for drag racing??? timing above 28 deg.???

[Bill Gohr]

For 100 oct. I would run 73 heads with about 170 psi. Don't use thick gaskets to compensate. Keep in mind you need to keep the flat on the heads as close to the piston as possible. Run the timing at 24 or 26.

As far as bakers motor I don't know, I helped them with the first one and he made a couple of other ones later. We tested 125 heads back in the 80's and saw no gain. Actually the best heads I ever had were 1967 OSS Gt heads, don't bother trying to find any.

[sixabove]

WHAT IS THE PREFERER EXHAUST STUFFING BLOCK?

JUST FOR REFERENCE HERE IS A PIC.

1996 115HP ON THE LEFT 1979 140HP ON THE RIGHT.

BOTH MOTORS I TORE DOWN HAD DESTROYED THE LOWER HALF OF THE STUFFING BLOCK ON THE #4 CYL. ANY IDEA ON CAUSES?

[Laker]

What did the Exhaust bubble look like on the 1996?
Did it match the bigger opening?

[Bill Gohr]

The preffered exhaust is the smaller one on the right. It was used from 73 to 77. That one on the right must be a 77 140 or it has the wrong powerhead on it. Use the smaller opening with the matching bubble. Also when you put this together remove the water passage that crosses the exhaust opening in the bottom of the block. Cut it out and weld it up.

[racer]

Might have a set of the 73 heads.

[sixabove]

i dont have my camera with me today.

putting the bubbles side by side the 115 bubble has larger intakes but the exhaust is much smaller than the 140.

the motor is probably a 77 but it has the new style gearcase and the newer style tilt and trim. i actually have $0 invested in the 140 which is about what its worth. tnt dont work and the owner can't find the heads that went with it and to top it all off the drive shaft is stuck in the powerhead. but maybe the bubble will work.

are the stuffing blocks still avalible from omc or is there an aftermarket supplier?

will removing the water passage help on upper end RPM?

i have a set of 135 heads from the early 70'S they produce about 135lbs. any good?

whats a good price on a set of high compression heads?

[sixabove]

just wondering?

[sixabove]

317848,9 on the gp clone i own but these heads make 215lbs any way to bring that down to 170?

319942,43 on the 135 heads i have

[Laker]

The 848/849 heads are 73s How much are they cut up?
the 942/943 heads are 74-76 135 heads. Slightly looser but still good heads.
If that is a 77 motor it may have the "Special" Tuner in it.
Check it out and post a pic

Bill What are 1967 OSS Gt heads? Why were they the best?

[sixabove]

THE BAD CYLINDER HAS 135#

[sixabove]

ACTUALLY ITS 7 3/4"

HAVE SOMETHING SPECIAL IN MIND FOR REMOVING THE 77 TUNER. WILL GET SOME GOOD PICTURES. LOL

[sixabove]

BETTER PIC

[Laker]

Loyd
Post a pic of those 135 heads cut to make 210 psi.