short stroke hemi

#1
Thinking of building a short stroke hemi. Take a gx160 bore it to 70mm , put a flat top piston in it and a hemi head with a black mamba jr. cam. Might be a torque monster !
 

CarPlayLB

Well-Known Member
#4
I always thought that a longer stroke combo made more torque!
Chevy destroked a 350ci (4" bore, 3.5" stroke) motor to 302ci (4" bore, 3.0" stroke). The Z28's with a 302 had no low end power. Have to dump the clutch at 3 grand to get rolling! They would easily rev to 7 grand though!
 
#5
In basic terms...
short stroke = higher RPMs/power
Long stroke = more low end torque/less RPMs
Bore means nothing really in this factor
 
#6
That's what i'm wanting to hear. Join in everybody, let's hear more about a short stroke hemi . Got some extra parts just laying around so might just try this out and see what happens.
 
#7
One old therory that I've lived by is " you can't out run cubic inch. I never liked the Idea of destroking. Bigger Stroke & Bigger Bore. :thumbsup: Thats what I like.
 
#8
I like the NoN Hemi engine... Comes .050 in the hole, put a Honda crank in .070 in the hole, then a Hemi flat top... .090 in the hole...
Now put a Honda 3.403 rod in for .010 pop up and a .045 gasket...
208cc semi long rod... Revs quick, and hauls the mail out of the corner... Less cc's, less stroke...but a quick revver...

Also I like a Honda with a Predator crank, .020 rod for .010 pop up .045 gasket... Revs quick with good bottom end pull...
Mini Stroker...
 
#10
I have the 208cc Champions...
Was able to get a better price at TSC on them than the Princess 208cc...

Also last year when Canadian Tire had the Rato 212cc on for $99.00 ... I picked up a few...

I have a lot of Honda parts laying around so been playing around with different combos...
 
#11
I have the 208cc Champions...
Was able to get a better price at TSC on them than the Princess 208cc...

Also last year when Canadian Tire had the Rato 212cc on for $99.00 ... I picked up a few...

I have a lot of Honda parts laying around so been playing around with different combos...
You managed to get TSC to budge on a price?
My Gosh the man can get blood from stones and perhaps turn water to wine lol.

Good show chum wish I was around for that I would have jumped in and added some cash and bargaining power.
If that option comes up for the 223 Champion you let me know and I will wire you some coin.

I'm going to try that rod you speak of depending on when the Canadian pesos stops dropping
 
#12
Our dollar really bits right now...
TSC had their screaming deal on $129.99 for the Champion...

But the 208cc Champion has a bigger wrist pin size for the pin and Rod, and a different taper on their crank...
It does come with a flat top piston... 18cc head with 27/25 valves...
It has 7 bolt hole side cover... Extra ribbing on the block front and back.
 
#13
Most 208 engine have that oddball rod do they not?
I have one from PA with that problem ( your Gx160 T2 long rod fix has that block potentialy back in play with a predator piston )

I have a few other 196 clones including a Champion and I noticed the differences around the block on the Champ.

Thanks for the taper issue tip, I just assumed it was a Honda style crank.
 
#15
Most 208 engine have that oddball rod do they not?
I have one from PA with that problem ( your Gx160 T2 long rod fix has that block potentialy back in play with a predator piston )

I have a few other 196 clones including a Champion and I noticed the differences around the block on the Champ.

Thanks for the taper issue tip, I just assumed it was a Honda style crank.
Not sure on the taper and wrist pin size... Sounds like it though...

Interesting thing...
I was in at TSC today... They have a new brand called the Cube...
The 208cc states it is 70mm bore but 56mm stroke...ummm possibilites
The 196cc is the same as the rest...
 
#16
Not sure on the taper and wrist pin size... Sounds like it though...

Interesting thing...
I was in at TSC today... They have a new brand called the Cube...
The 208cc states it is 70mm bore but 56mm stroke...ummm possibilites
The 196cc is the same as the rest...
Ya, saw those but assumed there was a typo.
Its hard to tell what you are dealing with.
Don't ask staff for help lol.
 
#17
There is actually Staff??? Ohh yes if you look long enough you might catch a glimpse of one.
My guess is that they are far in the hole with a dished piston to still come out at 208cc...

I know the Champion was .110 in the hole...
But I put a clone crank, Hemi Flat top and a .020 rod and got it to .020 in the hole...with a dished piston it was flush with the deck...
Or Predator crank with a .020 rod and a flat top for flush with the deck...
 
#18
There is actually Staff??? Ohh yes if you look long enough you might catch a glimpse of one.
My guess is that they are far in the hole with a dished piston to still come out at 208cc...

I know the Champion was .110 in the hole...
But I put a clone crank, Hemi Flat top and a .020 rod and got it to .020 in the hole...with a dished piston it was flush with the deck...
Or Predator crank with a .020 rod and a flat top for flush with the deck...
What did you find with the PA 208?
I don't have one of those Predator pistons to test with and the OEM piston is not compatible with my rods

I have a +020 in reserve for this build when the trail went cold on how to make the hemi head I welded up flow the way I wanted.
Yes I still have the PA head with the valves, but I remain infatuated with the idea of a canted valve squish head.

Ya one more thing is that bastard taper on the PA 208 crank?
 
Last edited:
#19
Have not had a PA motor at home yet... Looked at them in the store lots of times...

My Dad got a Subaru Ex21 from PA for $99.00...
I ended up getting a few Champions from TSC, and a couple Predators from Canadian tire that came with RTC6 heads...

I do have a Hemi head... They look interesting...

Best thing is to contact Youngengines he is the man when it comes to heads and carbs...

A friend I race with has a Young 390 carb and that thing rips!!! It runs just as good if not better than my Tillys...
But, the 390 carb is no slouch... Youngengines made almost 30hp with a 390 carb!!!
 
#20
Young engines and I have talked it over a bit at Bob's.
Great insights but the PA motors are a Canadian thing not too many have played with.
Just you and I talking about this in Canada.

I have a plan that involves more welding and some epoxy for the G200 head.

Rolling the dice on that PA predator and hope its not too deep in with the +020 rod and flat top.
I have plans but I need to see where it sit with a special 290 cam for valves, springs and pushrods.
 
Top