put my flathead on the dyno today

I'll second the vote to check the valve spring installed height and seat pressure while your waiting for parts......along with heeding the warning from Max at H+H.

 

I think Max is probably right as far as getting the last few horses from this engine, and maybe more than just a few!
But the OP mentions misfires and popping , etc. and this doesn't come from air/fuel mix starvation. I suspect the actual effect of restricted ports would be similar to the restrictor plate NASCAR uses at Daytona and Talladega in that the engine doesn't pop and misfire, it just flattens out.
I would ask about the exhaust system on the dyno, but it appears that it's open headers to atmosphere.
Just be sure to come back and let us know when you find the problem.
Dave

 

Any updates?

 

Not yet. I have ordered new points and condenser from Speedway, and a complete Chevy distributor converted by Bubba. Parts are supposed to be here next week, so will try once more to get the engine to run right.

 

Just because the dizzy is new doesnt mean its good, check that out first. Number two is, did you mention spark plugs? If so, I missed it. If you have Champions in there, stick them in the garbage where they belong. Screw in some new NGK B 4 L gapped to .030.

 

Think I bought some Autolite.

 

msd the whole thing,dist,coil,and box,i put a 7al box and matching coil and my 38 and man did i wake that ***** up,its definately electric,**** can all that daul point ****

 

any news?

 

Yes, put the engine back on the dyno yesterday. New condenser, new cap, new points on the Mallory dual points. Had purchased a Bubba converted distributor, but didn't fit , maybe the french flat is different from US flat. Shaft collar too large, so doens't fit.
ANyway, with 0.40 mm clearance on the points, engine seems to have picked up some hp, best reading was 90 at 3000 rpm. At this point, took the plugs out, and they were very very white, seems the carbs are not enough for the engine. It's fuel starved. Checked the jets, and are really very small, think they are 51 ( so the mechanic said). Don't know how he came out with this number.
ANyway, engine has possibilities, if I change the carbs or easier yet, modify the jets. Yesterday it was too late to do anything else on the engine.
Thank you everybody for all the input.
I am saying something that will seem a blasphemy here, but will concentrate on a 325 Hemi Dodge for my next project, the flat seems too complicated to extract some good power from it. I was planning on using the flat for my 48 Ford custom, but will change to the small Hemi, better suited to a large car like the 48. I also plan on driving the car for some distances, and want a faster driving / more powerful car. Lots of fast traffic and sometimes good power is needed.
Thank you again

 

sounds like you are on your way to get all you can get out of that engine for now.
It is a flathead, not a hemi for sure. How much hp were you hoping for?
Have fun
Wil
www.sakowskimotors.com

 

I offer one suggestion and that would be to hook up a scope at the motor to check the plug wire resistance and ignition while doing the dyno pulls. This will show if you have any wires-dizzy-condenser or point problems which would eliminate that part of your system allowing you to test elsewhere for problems. Good luck

Now there was some real good advice. there only a couple of people left in the world who own a scope and knows how to use it and one of them (me) is retired BUT you can tell in an instant of it is an ignition problem or not. Beats guessing everytime. Also the advice you got about just because it is new does not make it good was right on. Don

 

Mallory needs more than 0,4mm gap.did you check dwell?
white plugs mean lean mixture.
51 jets are not too bad , should be ok.Did you measure them?
Are you sure that your fuel pump is working correct?

Michael

 

Had a local shop run a flatty on a dyno last week, called me in to see it run. Motor was an 8RT. Dizzy was an original "loadamatic" (no mechanical advance only vacuum and the vacuum was not hooked up). Motor had 2 94's on an early intake and a set of Offie 400 heads. No idea whet cam was installed. Made 87 HP @ 3500. We set the dizzy @ 24 degrees advance @ 2000 rpm for the pull.

Flat owners should really buy Joe Abbins new book on flatties. It shows a lot of dyno info as well as a lot of intake and exhaust flow charts for various heads; with relieved and non-relieved heads. The book is only $25.00 and is an excellent read with many glossy pictures.

To order go to this site:

http://www.roadrunnerengineering.com

 

I am done with the flathead. Was hoping for something around 130 hp, and could probably get there if I was more motivated. 90 at 3000 is not too bad, but I feel I am missing something. I prefer cars with more hp, and the flathead can't get them. Of course, it's an engine that was born in 32, can't pretend too much. My 39 will soon have a 327, the 35 windows has a 354 Hemi, the 32 roadster will have a 392 5 speed with Weber carbs, and the 48 will have a 325 Dodge Hemi. Maybe because I have collected Mopar cars all my life now I can't live without some Hemi valvecovers in front of me. .
Thank you for the help.

 

Like one old LSR said, " I've never spent SO much money to go SO slow !"....

 

was the cam ever dialed in correct.

 

Send the engine over to me to Germany.
I like flatheads!!!

 

This is the second time that you said the engine was born in "32" ? if that is indeed the case those engines were 60 horse. if your getting 90 horse you done good.

just a thought

 

a bone stock French Flathead has 100 HP already when the throttles can open completely
at least that's what our dyno showed

BTW: One of the Bubba's new dizzies for French Flatheads is for my '37.

 

how about draw from the fan? that is some times up to around 10hp. Thanks for the info My flatties is a late model Merc

 

Can you just fit a regular 8BA/8RT front cover to take a 'USA-type' distributor, or is there more to it than that?

 

The vac signal to the dizzy is halved with twin carbs .You will need a cluey auto lectrician to spin it up and check the advance ,initial and total , plus the curve .Also ,pending on the model of dizzy ,some of the 8ba types had brakes over vac .Sort of weird and no sir , I dont like it !

 

I guess he ran a Dizzy with mechanical advance and without vacuum advance anyways...
Friend of mine had a A-V8 Roadster and a very nice Flatty in it.
He was building the car somewhere around 8 years or so cause everytime he was short in beeing finished with it he changed his taste and then dismanteled it again completely to make it different. Never drove it.
Only wanted to say that he was a perfectionist and never satisfied with anything.
He had Eddie Meyer Intake and Heads on a 8BA. Gave the Intake to Chrome it and that allone (without the intake) was abbout 400Eur.!!!
So he spent all his money in that Flatty without regards of costs...
At the end of that story he went on an engine Dyno and ended up with 80HP just like the fella that started tthe thread. That´s less than advertised HP of original engine.
Mike Lange (don´t know his HAMB name) bought it and took it apart.
Said it´s no wonder that engine didn´t make power. inside everything was left original. Only dress up parts were put on. he must have spent a fortune on them.
The guy with the roadster built a Chevy 454 Bigg Block after he sold the Flatty but ended up selling the car in parts before gettin it on the road.
You heard that one for sure "It´s all in the heads"....well Regards the Flatty I would say
"it´s all in the block" weather you make power or not!?