H-mod Engine Options

Currently researching a new restoration project; an H-mod racer, similar to the Mercury "H-bomb". (But slightly bigger )



We believe the project car to be a "La Boa", which is mentioned in the "Vintage American Road Racing Cars 1950-1969".
According to that book, engine option for the Mk. 1 is a Coventry Climax, and the Mk. 2/3 are Climax, Saab, Lotus twin-cam, Porsche.
The car is currently setup to run a Mercury outboard, similar to the H-Bomb pictured above, RWD, chain drive.

A BMW 700 motor came up as a possible option, which would be similar in execution to the Shirdlu shown here at BAT when it came up for auction. BMW 700 drivetrains, however, aren't readily available and I've already reached out to Mr. Selbert to inquire as to availability. There aren't many, it seems.

A Porsche/VW powerplant could be a possibility, but, the fan shroud would likely require modifying the rear bodywork. That's also a pretty big lump to have hanging out behind the driver, and as the car is really quite small, would probably be detrimental to any kind of cornering ability.

So, I would be interested in other forum members' thoughts on the matter. The easiest option would be to retain the Mercury, but I'd like to have a complete picture of what is available/possible during the research phase. Perhaps there's some H-mod/DSR historians who could provide a bit more insight than I can immediately gather on the world wide web. On that note, I think I found an old (6+ years) thread with Peter Krause on it, if he's watching perhaps he could chime in?

Thanks!

My initial question is "Why are you thinking of changing what is historically correct?"

As for the Porsche/VW engines, remember that HMod, depending on the year, limited the displacement to 750cc or 850cc. If you put a larger engine in, you no longer have an H-Mod.

Excellent point Stefan - only entertaining options on behalf of the car's owner, and partly due to a current lack of knowledge of the period equipment on my behalf. I don't know that the Mercury was the original motor for this car, but if that is the case, then retaining it would be correct.

What would you consider to be most appropriate in this case?
I suppose a more precise identification of the actual car will help, once I know that, I will follow up.

A few quick photos of the car can be found here http://imgur.com/a/FblJT#0

Ian,
Great little car, I know very little about them so I did a couple of Google searches and found this. I thought it might be of interest, although you might have already seen these links.

Anyway, here you go.

http://sportsracernet.smugmug.com/H-Mod ... d-Specials

http://www.vintageracerules.com/forums/ ... g_class,_D

Regards,

Ian:

What is the thing in the last picture of the rear suspension that looks like it needs to be replaced by a coil over? It looks like it has a rubber bushing in the middle.

Also, where does the rod that attaches to the top link of the rear upright (hub carrier) go? I don't mean the radius rod or the anti-roll bar but the black rod that goes through the hole in the chassis member. I assume in this pic the half shaft is missing.



Mack

Rick - thanks for the links! I've seen them, but I keep losing the bookmarks so now, I know where to find them!

Mack - not certain on either point; we only spent a short while with the car, and will be investigating further soon. The halfshafts are missing. The uprights are place holders, and it's likely the case that a lot of the suspension is the same. I think this was very much a work in progress, or yet to be started, when the current owner purchased it. Sorry to leave you hanging. Hope to have some more details in the next week or so.

Finding a relative of this chassis, if one exists, is going to be important me thinks.

Excellent point Stefan - only entertaining options on behalf of the car's owner, and partly due to a current lack of knowledge of the period equipment on my behalf. I don't know that the Mercury was the original motor for this car, but if that is the case, then retaining it would be correct.

What would you consider to be most appropriate in this case?
I suppose a more precise identification of the actual car will help, once I know that, I will follow up.

A few quick photos of the car can be found here http://imgur.com/a/FblJT#0

Neat car!
The Mercury certainly could have been the original motor, as the H-Bomb proves such a configuration did exist in-period.

I don't necessarily believe that every racecar needs to be returned to its original configuration. Rather, I would choose the car's most "significant" configuration as a point to aim for. Not knowing more of the car's history, the Mercury seems to be the simple and logical choice. If you later learn that the car originally had a Crosley or SAAB or something else in it... Then there's a decision to be made.

If you are struggling with a lack of information, there is a YahooGroup for HMod. https://groups.yahoo.com/neo/groups/HMOD/
I'm a member. There are a lot of members actually, though only a few are active at posting. Still, if you send photos and want to identify something, SOMEONE there will probably recognize it.

HMod was the "tinkerer" class in the 50's-60's. No other class allowed for so much variation and invention, especially at such a low cost of entry. You could race everything from a near-stock production car, to a wildly modified production car, to a modified racecar, to a pure 100% homebuilt. Accordingly, "mystery" H-Mods show up all the time.

If you are struggling with a lack of information, there is a YahooGroup for HMod. https://groups.yahoo.com/neo/groups/HMOD/
I'm a member. There are a lot of members actually, though only a few are active at posting. Still, if you send photos and want to identify something, SOMEONE there will probably recognize it.

HMod was the "tinkerer" class in the 50's-60's. No other class allowed for so much variation and invention, especially at such a low cost of entry. You could race everything from a near-stock production car, to a wildly modified production car, to a modified racecar, to a pure 100% homebuilt. Accordingly, "mystery" H-Mods show up all the time.

Excellent - thanks for the link to the HMod group, that should provide for a great resource.

It does seem that the Mercury would be the obvious choice, pending something else turns up. So, I think best to do some homework, and then see what best suits the needs and parts availability. From what I've been reading, it does seem like there was wild variation and innovation taking place during that time - really an interesting class to be researching. This should allow for a serviceable and period appropriate solution.

Will follow up when we find out more information. Thanks again!

OK - something of a revelation. I was close, in my googling, when trying to track down the car, but the owner passed along some information that got me the correct search terms. I was just a page or two away on the following site.

http://sportsracernet.smugmug.com/VintageSportsRacersnon-H/Murray

^^ That link contains both ads for the car when it was for sale, and provides enough back story to cement the Mercury as the original/correct motor.
Cool, time for more homework!