Tell me about the Sport G class

[KG4]

Specs and speeds,Thanks guys.

[2us70]

As I recall it was a 70 ci class using product in motors. The first G boats I remember ran inline 6 Merc 700s. There are pictures of a early G class Raveau scattered around on this forum. For a brief time Chyrsler produced a competitive G class motor. Finally the 4 cylinder Merc 800s then the 850s defined the class. In the early 70s the boat length was dropped to 13 feet. I ran a little of both SG and G production in those days. A good SG boat ran over 70 mph but I don't remember exactly how fast we were running.

[OLEGATOR]

As I recall it was a 70 ci class using product in motors. The first G boats I remember ran inline 6 Merc 700s. There are pictures of a early G class Raveau scattered around on this forum. For a brief time Chyrsler produced a competitive G class motor. Finally the 4 cylinder Merc 800s then the 850s defined the class. In the early 70s the boat length was dropped to 13 feet. I ran a little of both SG and G production in those days. A good SG boat ran over 70 mph but I don't remember exactly how fast we were running.

and if you wanted to keep up with mark hauptner, it looked like you needed to run about 5+ mph faster lol!!!

[2us70]

That was for sure. I never ran against Mark in SG but I did race him plenty of times in SE.

[DanUmbarger]

440290In 1970 I ran 64 mph with my Hustler 13' and Merc 80

[WaterZebra]

As I recall it was a 70 ci class using product in motors. The first G boats I remember ran inline 6 Merc 700s. There are pictures of a early G class Raveau scattered around on this forum. For a brief time Chyrsler produced a competitive G class motor. Finally the 4 cylinder Merc 800s then the 850s defined the class. In the early 70s the boat length was dropped to 13 feet. I ran a little of both SG and G production in those days. A good SG boat ran over 70 mph but I don't remember exactly how fast we were running.

Were the Merc 800s and 850s all short shaft models? Aside from kicker fishing motors, I don't think anybody makes the bigger engines less than 20 inches these days. My first "big" outboard was a Merc 800. Ran all day at WOT and never missed a beat. They were a strain to manually tilt. At least the straight 6's had enough top mass / weight to "counterbalance" the mid section and gearcase.

[99fxst99]

If you ran SG in the Mid-Atlantic in the 70s you had to beat Rayner Blair!

[2us70]

OPC boat of that era pretty much ran short shaft motors. I never owned a long shaft motor until I bought a fishing boat in 2001. The 800s and 850s shared the same gear case with the 1500s. They had a much lower gear ratio allowing them to run the same propellers as the 1500s. Those great big slow turning props really worked well on the G class boats.

[WaterZebra]

OPC boat of that era pretty much ran short shaft motors. I never owned a long shaft motor until I bought a fishing boat in 2001. The 800s and 850s shared the same gear case with the 1500s. They had a much lower gear ratio allowing them to run the same propellers as the 1500s. Those great big slow turning props really worked well on the G class boats.

It probably wasn't "legal" for SG but did anybody ever try to run a low water pick up 1500XS gearcase on a Merc 800 nor 850? (LOL)

[2us70]

The 850xs may have had a low water pick up. I stopped racing just before the xs motors came out so I never saw one up close.

[WaterZebra]

The 850xs may have had a low water pick up. I stopped racing just before the xs motors came out so I never saw one up close.
I completely forgot about the 850XS! Seems that all the Merc racing press releases were focused on the 650XS and 1500XS. I think you can thank OMC and the SE class for overshadowing the FG and SG classes and 850XS. Was SG / 850XS, etc ever run in Europe? I suppose the 850XS did not run in Mod 50 against OMC because of displacement. Not sure that and 850 would stand up to OMC's Mod 50 / 110 hp output? I think Merc kind of softened their grip limiting sales of the XS models to "qualified racing enthusiasts" (APBA) not like what the did with Twisters, T2, T2X etc. Only time "XS" showed up again on decals was for the 1750XS (T3). "XS" has only since reappeared in 2019 (4 stroke market). I think the 850XS only showed up in Merc's product catalog for 2 years (1976, 1977)?

[Mark75H]

Yeah, E is 49ci and the 800, 850 and 850XS were 66ci. The original XS motors had to be advertised in the regular catalog and sold thru regular dealers to qualify as production motors

[FMP]

As I recall it was a 70 ci class using product in motors. The first G boats I remember ran inline 6 Merc 700s. There are pictures of a early G class Raveau scattered around on this forum. For a brief time Chyrsler produced a competitive G class motor. Finally the 4 cylinder Merc 800s then the 850s defined the class. In the early 70s the boat length was dropped to 13 feet. I ran a little of both SG and G production in those days. A good SG boat ran over 70 mph but I don't remember exactly how fast we were running.

I'm wondering, maximum 70 ci or a couple more allowed. The triple CHRYSLER then i believe was a about 72 ci. Later in 78/79 they did put out a slightly shorter stroke for a specific reason , maybe class racing but marketed it for higher rpm running, along with a 17' leg and the newly introduced one piece lower, not a speed master type but the powerflow .
I'm wondering if that short short stroke was a leftover from those class motors of a decade earlier, if sticking to the ci limit was absolute .

[99fxst99]

It probably wasn't "legal" for SG but did anybody ever try to run a low water pick up 1500XS gearcase on a Merc 800 nor 850? (LOL)

Don't know about this, but I do know of a JP boat that ran an 850 gearcase for a long time and was never caught. No one ever thought to check it. It was said to help acceleration on a short course turning a bigger prop slower.
Don't know how true that was be he always ran good!

[2us70]

Sounds like a plan to me. I wish I had thought of that trick when I was running EP. Might have helped me against those OMC loopers. In a production class that might not make the motors run out of revs but in a sport class with much lower weight limits you would probably over rev the motors too much.

[FUJIMO]

yes, the 850XS motors came from the factory with the XS gearcase. same housing as the 1500XS housing. different ratio. there were two different XS housings produced. early & late. early had more intake holes. later had less intake holes.

[Instigator]

Great thread!

[vintage v4]

I'm wondering, maximum 70 ci or a couple more allowed. The triple CHRYSLER then i believe was a about 72 ci. Later in 78/79 they did put out a slightly shorter stroke for a specific reason , maybe class racing but marketed it for higher rpm running, along with a 17' leg and the newly introduced one piece lower, not a speed master type but the powerflow .
I'm wondering if that short short stroke was a leftover from those class motors of a decade earlier, if sticking to the ci limit was absolute .
440448440449
Yes, the Special Edition Charger was introduced for the Sport G class. For a few years there was a good field of Chryslers with TCPBA up in region 8. The Special edition was de-stroked to get under the 70 cubes limit for SG. Ron Baker worked for Chrysler and he was the force behind getting them back into OPC racing at the time. There were plenty of cleaver props available because the powerflows were 15 spline so Merc wheels fit. It was a good competitive class that was entertaining to watch.

[WaterZebra]

[QUOTE=FUJIMO;3137545]yes, the 850XS motors came from the factory with the XS gearcase. same housing as the 1500XS housing. different ratio. there were two different XS housings produced. early & late. early had more intake holes. later had less intake holes.[/QUOTE

If it was possible to swap these gearcases (no visible signs of difference), how would you "inspect" for that? Comparison of hand-turning the flywheel with a marked position of the prop shaft? Would there be a performance advantage (hole shot) by using a 850XS case on a 1500XS and vice versa? Would anybody even think of this possibility during a breakdown inspection. Inspection criteria was always focused on engine bore/stroke displacement, exhaust ports, etc I know this thread is focused on SG but it now makes me wonder if gearcases were being swapped undetected in SJ considering how intensely competitive it was.:rolleyes:

[OLEGATOR]

[QUOTE=FUJIMO;3137545]yes, the 850XS motors came from the factory with the XS gearcase. same housing as the 1500XS housing. different ratio. there were two different XS housings produced. early & late. early had more intake holes. later had less intake holes.[/QUOTE

If it was possible to swap these gearcases (no visible signs of difference), how would you "inspect" for that? Comparison of hand-turning the flywheel with a marked position of the prop shaft? Would there be a performance advantage (hole shot) by using a 850XS case on a 1500XS and vice versa? Would anybody even think of this possibility during a breakdown inspection. Inspection criteria was always focused on engine bore/stroke displacement, exhaust ports, etc I know this thread is focused on SG but it now makes me wonder if gearcases were being swapped undetected in SJ considering how intensely competitive it was.:rolleyes:

after having endured numerous inspections for records and national championships, i can assure you, gear ratios were one of the first things checked. it was one of the easiest. they even checked my water pump. to see if i had modified the impeller.

[2us70]

If all they were doing for inspection was weighing boats I guess you could get away with that kind of lower unit swap. In SJ I think they were running pretty much all the prop they could get on the those motors. I don't think they would handle the lower gear ratio very well at top end. They might get out of turns a little better but once they aired out they would likely overrun the power and torque curves of those stock power heads. An stock inline Mercury can only flow so much air.

[FMP]

440448440449
Yes, the Special Edition Charger was introduced for the Sport G class. For a few years there was a good field of Chryslers with TCPBA up in region 8. The Special edition was de-stroked to get under the 70 cubes limit for SG. Ron Baker worked for Chrysler and he was the force behind getting them back into OPC racing at the time. There were plenty of cleaver props available because the powerflows were 15 spline so Merc wheels fit. It was a good competitive class that was entertaining to watch.

Yes thats the one, 1980. Tough to find that leg, I run the 20" with 1.73 powerflow. So how'd they get under the rules back in the late 60s ?

[vintage v4]

Yes thats the one, 1980. Tough to find that leg, I run the 20" with 1.73 powerflow. So how'd they get under the rules back in the late 60s ?
They weren't allowed before they got under 70 cubes, they wouldn't have been competitive with the 2-piece lower anyway.

[FMP]

They weren't allowed before they got under 70 cubes, they wouldn't have been competitive with the 2-piece lower anyway.

I see, no factory race lower permitted.

[2us70]

The original SG motors were DR motors and could run Speedmaster lower units if I remember right. Maybe Sportmaster units as well. Lil Abner and Olegator will know for sure.

[WaterZebra]

Don't know about this, but I do know of a JP boat that ran an 850 gearcase for a long time and was never caught. No one ever thought to check it. It was said to help acceleration on a short course turning a bigger prop slower.
Don't know how true that was be he always ran good!

(LOL) Out here in the wild west, I guarantee you nobody ever checked gear ratios. Even the inspectors schools (region certified) didn't cover it. Now I'm beginning to wonder how many US1 and region high points titles were legitimate? This is something that was out of reach for many weekend racers. Either you had deep pockets for acquiring a myriad of engine components to experiment with or had access to a large inventory of parts (dealer) to find the "perfect" part by dimension / weight. In other words: blueprinting. One of the reasons I quit racing. Did it for the fun and technical experimentation and not to throw an endless pile of $$$ at it. Now that I look back on it, I think the SG class would have really been something using a Merc 850XS on a Sport E hull (with a safety cell of course).

[2us70]

I got torn down several times over the years. Twice by Edgar Rose himself. Never failed a motor inspection.

[FUJIMO]

2us70...only winners got torn down.:smiletest: congrats.

[kdtilt]

441495

May still be his favorite boat.

[FUJIMO]

https://www.screamandfly.com/attachment.php?attachmentid=441495&d=1560299499 (https://www.screamandfly.com/attachment.php?attachmentid=441495&d=1560299499)

[RogerH]

Rayner's E&T today..still running in Vintage with a 1500XS
441542

But this may be his favorite now
441543

[lilabner]

The original SG motors were DR motors and could run Speedmaster lower units if I remember right. Maybe Sportmaster units as well. Lil Abner and Olegator will know for sure.

Very true. We chose speedmaster. the boat actually handled better. My prop was my saviour though. Mercury props were terrible. I bought a bronze Michigan OJ prop that looked like a chopper.. Marcel Raveau beat on it all the time.. I used it on the 800 and 1000 also. Same boat. Lucky to have never thrown a blade.

[bearclaw]

This is fun, this takes me back... My best friend back in high school ran Sport G in Region 6 from the '74 to the '77 seasons. Did pretty well as I recall. He and his dad went out to Colorado to to get the boat, it was a Marathon tunnel, and it seems like the OAL was 16-16.5'. He started with a '74 850 short, then in the '75 season is when the XS's were available, so he switched to that.
As mentioned, same unit as the 1500 except with 2.33/1 gears. As far as props, his were all cleavers, at least a couple were Mercury but I don't believe they all were. I know they had all been "worked" by one of a couple known prop wiz's in the region.
Seems like straightaway speeds were in the upper 70's. The kilo record was probably in the low 80's at the time.

[DanUmbarger]

Don't know if they had SG back in the early 60's but my dad ran a Switzer Shooting Star with an inline 6 in G class.443851

[WaterZebra]

Very true. We chose speedmaster. the boat actually handled better. My prop was my saviour though. Mercury props were terrible. I bought a bronze Michigan OJ prop that looked like a chopper.. Marcel Raveau beat on it all the time.. I used it on the 800 and 1000 also. Same boat. Lucky to have never thrown a blade.

I used to run bass boat chopper props in Sport J and used to get razz'd by my SJ competitors about using them until I soundly beat them with choppers, then the snickering stopped. Always thought that the Merc thru-hub exhaust cleavers were vastly overrated.