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MG Midget and Sprite Technical - HP Hunting What next?

Ok so I have a 12CJ engine thats bored 0.30 over, It has higher than normal compression, an sw5-07 cam (retarded 7 degrees), standard lifters, intake valves enlarged to 1.401", a maniflow LCB and single box exhaust system, stock dizzy, and standard stroke. It is used for regular street use and I never rev it much beyond 5000 RPM. Which of the following is would bring more HP gains?

Aldon Yellow Distributor

or

Maniflow 20º twin SU Intake manifold

and if its the latter, should I go with the one that is designed to take either Hs2's or HS4's or is the HS2 only version the way to go?
S.A. Jones

S.A. I'd go for the intake over the ignition. As for the ignition, no need for anything trick, just get your stock unit rebuilt and recurved by Jeff at Advanced Distributors after you settle on the rest of your engine package so that he can set up the best curve for your package.
I'd go for the HS2s. Unless you are racing and running very high rpm you'd never need the flow capacity of the HS4s on your engine and would probalby loose some low end torque in the process.
As far as HP gains, I doubt if you'd notice much with either mod from what you have now. You're talking very incremental gains from the intake or dizzy compared to the mods you've already got. Maybe on the dyno, but I really doubt that you'd notice any major improvement in the driver's seat.
Bill Young

The dissy can not increase HP, if it did when fitted it would mean that your old one was NOT timed in correctly. What a different dissy can do is perhaps give you better fuel economy or better mid range drivability if your old one was particularly bad.

Regarding a manifold, IMO these kind of increases tend to be almost measurable on a rolling road, although it will be small, however you will probably not detect an increase simply by driving.
Robert (Bob) Midget Turbo

I'd remove the carpets and door panels and such to reduce weight. ;)

Seriously, though I agree with Bob that a dizzy will not increase your max horsepower, but it might give you a wider band of power if your current dizzy has a really oddball curve or is just worn out.

Trevor Jessie

Seth.

Firstly, I would ask why are you looking for more 'power'...? With the set up you have, the camshaft will give you good torque. (I also can't understand why you say you have the SW5-07 retarded by 7 degrees).

If you want more 'power' just use more revs, you engine should be safe to 6500 with ease and the cam will 'work' to those revs well.

Remember:

'Torque' will give you driveability and acceleration.

'Power' will give you a greater top speed.

That's why I can't see why you are looking for more 'power'...

Mark.
M T Boldry

Hey Seth,

I "Advanced" my cam by 4 degrees, So im looking forward to seeing how torquey my engine is going to be.

Im curious why you "Retarded" for horse power, for street driving I never get that far up the revs range except for highway driving. Then agian with all the truckers vs. one little ol midget, thats probably a good idea to set it up for top end power, LOL

The only place to buy Maniflow intakes in the USA is APT, and they cost just under $400...if you got the tools and the skill level you can make your own for under $10...I could never get my homemades to turn out well, they always warped or leaked,,,but Im only a extreme basic welder, so I scraped that idea, but No Way was I going to fork that much money out for 10 dollars of scrap metal

My recommendation would be roller rockers, or re-configuring the size of the wheels, tires, and rear differintial gearing.


Prop
Prop

Hey seth,

Have you considard knief blading the butterflys, Thats good for at least 30 hp, Isnt that right robert?

LOL.

Prop...Just kidding, its really only good for 40 hp...Prop
Prop

Agree with many comments above.

Time the cam properly, have it set up on a rolling road, and use 6.5K or more to enjoy the power peak.

A
Anthony Cutler

Time your cam in, fit a HIF or a DHLA40, 1.5:1 rockers, rolling road session & rev it around to 6500 or until your scared.
Brad (Sprite IV 1380)

A dissy will not improve your peak HP as optimized on a dyno. It can, however, optimize your torque over a wider band of rpm. Unless you are using your A-Series as a pump engine (hoping that it magically converts into a Coventry), the RIGHT dissy can make a big difference on the road. As Bill indicates above, Jeff has a good reputation in many dimensions.

OTOH, ISTR that you were complaining that your Midget was TOO fast when you put the cam in...
David "HP is just a bench-racing number" Lieb
David Lieb

If you are loking for some real HP, try this page. Lots of info;)

http://www.angelfire.com/nc2/mycoffeecan/page1.html
Tim Michnay

Hey Tim,

Another tip...for sticky tires.

Soak the regular street tires in Dog Doo doo for a couple of days in the hot sun or bake in your oven (wife permitting) at around 200 degrees for 5 hours, the enzimes and acids in the dogs "Pile" actually soften the tire compound to a tacky touch... A WARNING... the more "chocolate dog candy" and the fresher it is, will accelerate the process even faster, so becareful you dont over do it, or your tires will get super sticky.

Its an inside trick, all the good street racers like "Vin Desiel" do it.


Prop
Prop

Prop,

After that treatment I expect the expressions "goes like stink" or "sticks like sh*t to a blanket" would be applicable.
David Billington

Gee Prop, I never would have thought of that. Maybe that's why my lawnmower corners so well. We have a great supply of land mines in our yard!
Tim Michnay

LOL.

That was creative wasnt it...that could be the making of a new book, on "How to really create HP, the Internet way. the whole book would be stupid tips like this, including my favorite of all time...How to port the engine...were the guy got two 25 lbs bags of fine sand fired the engine up and started shovling the sand into the air intake manifold...now that was funny, not sure if it was true or not, but that story still cracks me up

Prop
Prop

Don't forget the lowering kit that consists of four 16-penny nails (and the budget version with only one nail, but it takes four times as long to "install").
David "I could loan you mine" Lieb
David Lieb

Prop-
Don't laugh about the sand. To bed the rings on an Internationa H tractor, the factory manual tells you to put something like 2 tablespoons of Bon Ami powder through the carb and let the engine run for a while.
Tim Michnay

This thread was discussed between 14/10/2009 and 19/10/2009

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