HPE 4mil "bolt in" stroker kit

Location
Chicago
How hard is this kit to install yourself? For example, I would say I have moderate mechanic skills, but have never assembled a 701 based motor on my own? Doable, or don't bother?
 

holeshot

HPE products
Location
ca
How hard is this kit to install yourself? For example, I would say I have moderate mechanic skills, but have never assembled a 701 based motor on my own? Doable, or don't bother?

Very simple install. The only part of the install you will need help with in your instance is measuring squish clearance. (Piston to head clearance)
 

D-Roc

I forgot!
817cc 85mm flat top @185 psi. Just waiting for my wife to get back from town with my spark plugs.
6940033c6b5747f13f7ea9b968243bcf.jpg



Sent from my iPhone using Tapatalk
 

holeshot

HPE products
Location
ca
Adding this to this thread;

Sorry ive been a bit busy. I like the 62t cylinder MUCH better. The transfer allignment is dramatically better, auxillary transfer windows are 2mm wider than the x, exhaust and transfer timing are great even for stock stroke on the 701 62t but 760 a touch too much blowdown for stock stroke to feel as strong off idle as you would expect it to. Total loss can help there and hpe 4 or 5 mil kits wake the 760 dramatically down low. The 62t 701 and 62t 760 do not have the same port timing or transfer angles by the way. 760 has more exhaust timing about 4 degrees more, and 33degrees blowdown compared to 31 on the 62t 701. The 62t cylinders are stronger but do require timeserts or heli coils so they can accept the 61x m8 exhaust bolts. I do think a slight amount if torque might be lost to the larger exhaust passages on the 62t compared to 61x but the benefits outweigh that quite a bit.
When Porting its very inportant to keep roof angles the same on opposing windows and trade pros know to avoid changing roof angles unless absolutely last ditch necessary for this reason. The 62t roof angles can go undisturbed for the mostpart when porting but the 61x has to be moved considerably due to factory misallignment a big plus for the 62t. We want minimal turbulence leaving the port window and a clean collision or merge between opposing transfer charges to minimize fresh charge from mixing with residual exhaust gasses to avoid as much charge dilution as possible. Turbulence in the dome is an entirely different situation.
 
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holeshot

HPE products
Location
ca
as far as stroker cranks and the different cylinders.
760 is great stock or ported with either 4 or 5 mil hpe kits.
The 62t 701 is best with 4 mil non ported and great with 4 or 5 mil hpe when ported.
The stock 61x will benefit from a 4mil hpe kit for sure. But due to transfer misallignment either a properly ported 61x or a swap to 62t cylinder is where the gains get serious. The 4 mil kit on the 61x will keep transfer timing within 1 degree of stock and exhaust timing will stay within 2 degrees. Blowdown will go down about 1 degree. So the stock 61x cylinder will possibly lose just a touch of peak rpm as in 100 rpm and gain hp from idle to peak rpm noticeably. Youll gain case volume and lift the sleeve upout of intake port and transfercups so stock cases behave ported, youll gain dwell as the piston leaves tdc making better use of combustion, youll pump the cases better due to less dwell at bdc, and youll have added leverage at the crankpin, and you will increase displacement. All adds up to nice gains you will feel everytime you grab throttle. By the way 90% of flow in the reed duct is at the port roof so lifting the sleeve there is goodgood.
 

JustinB

Proof I has a brain \l/
Location
Oxford, MS
Is there a link to order these from? And a stock 62t cylinder will be better than my 61x cylinder with this?

I'm interested in this for my new B1 project. how will this react to a 61x bottom end? I guess if I have to break the bottom end open, I can swap to dual 38s. But I'd rather tune a single.
 
Location
Stockton
Is there a link to order these from? And a stock 62t cylinder will be better than my 61x cylinder with this?

I'm interested in this for my new B1 project. how will this react to a 61x bottom end? I guess if I have to break the bottom end open, I can swap to dual 38s. But I'd rather tune a single.

You can send holeshot a private msg
 

holeshot

HPE products
Location
ca
Is there a link to order these from? And a stock 62t cylinder will be better than my 61x cylinder with this?

I'm interested in this for my new B1 project. how will this react to a 61x bottom end? I guess if I have to break the bottom end open, I can swap to dual 38s. But I'd rather tune a single.

Works great with 61x bottom end, stick with a single carb on 61x. Youll see better results with a 62t cylinder but that doesn't mean you wont see good results with 61x cylinder, they work good.

You can always call or txt-matt
714-931-3860
 
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