E85 Predator 212cc build

Lykkan

Member
Hi, I'm a new girl here. I've rebuilt a few engines but I'm by no means an expert, and I appreciate any constructive criticism etc.
I'm building a 212cc predator hemi engine for high compression and high rpm (9k peak would be OK) to run e85 only.

I've milled the head so the combustion chamber is down to 17cc, and ported intake and exhaust.

I modified the intake rocker only so it's a 1.27 ratio intake / 1.24 ratio exhaust.

I currently have the stock cam but would like to upgrade to something harder.

22# springs.

Billet +.020 rod

Fly cut piston, waiting on rod to be able to check clearances..

I want a Billet flywheel, and I'll get one before I even try revving it way up.

Compression currently is calculated to 11.7:1 with .012 head gasket but may need to go with a thicker gasket to assist in valve clearance.

Vm22 carb kit

Open header

Removed oil sensor and governor

Anyone see any issues with my current intentions or build? I've never tuned for e85 but I've had many a experience with jetting carbs. I'd appreciate good information from some experienced builders. I'm not sure what timing I should go with either. Thanks!
 

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Lykkan

Member
It's since been cleaned up more, I know I need lighter rockers for higher rpm's and I'll get them also when I can
 

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flattop1

Dawg 89
Looks good to me .
34* should be safe.
 

1fasttiller

Member
Whew.. what did you mill the head with a belt sander? I'd be very cautious as it looks pretty rough and may give you issues sealing. I'd also be very cautious with those homemade rockers, you have greatly affected the metal temper and strength of them now and you are talking serious RPM to not be using a real roller rocker setup. You will definitely need a cam! That stock cam won't come anywhere close to what you're wanting to do.
 

Lykkan

Member
Whew.. what did you mill the head with a belt sander? I'd be very cautious as it looks pretty rough and may give you issues sealing. I'd also be very cautious with those homemade rockers, you have greatly affected the metal temper and strength of them now and you are talking serious RPM to not be using a real roller rocker setup. You will definitely need a cam! That stock cam won't come anywhere close to what you're wanting to do.
thank you for info. The 1.19 rockers increase intake lift from .224 to .266
I threw all my details into desktop dyno - the non-dotted lines are effect from the 1.19 ratio rockers. I have indeed changed their strength, but the push rod's location in the rocker is now further inward, where it has more structural integrity of the edge vs how it was before. Hopefully they hold up at all. I do want roller ratio rockers eventually but $$
 

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Lykkan

Member
I started assembling the engine and checked for valve piston clearances. Measured the cam and it's actually a bit smaller than anything I've read online as them being.
I measured intake lift is .220 and exhaust lift is .223
Probably going to order a cam before I anticipated as it does limit my build a bit
 

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Lykkan

Member
made a 1" exhaust header for it. Wanting to have a removable motorcycle muffler (resonator) for it.
Engine's all together. Waiting on carb still. Picked up a pipe bender for the kart chassis I'm designing. Gonna be slow progress.
 

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Kart43

Member
Can you show how you measured a 17cc chamber and arrived at 11.7:1 ratio. Your Desktop Dyno software is a bit on the optimistic side.
 

flattop1

Dawg 89
Question is ; are you aware welding galvanized metal gives off a poisonous gas .
 

Lykkan

Member
Can you show how you measured a 17cc chamber and arrived at 11.7:1 ratio. Your Desktop Dyno software is a bit on the optimistic side.
Optimistic or not, I'm not racing so I'm not aiming for a specific number, any improvement I can get out of it on a fair budget and I'm happy with it.
Compression Ratio.jpg

I have the longer billet rod, and the deck is shaved to bring the head volume down to 17 cc measured
 

Bandmn

Member
nope I did not lol
I weld for a living and yes this is a true statement.... Now im not saying it will kill you but will make you feel like you have the flu, headaches etc. I had metal fume poisioning 1 time this year and it SUCKED!
 

Lykkan

Member
I weld for a living and yes this is a true statement.... Now im not saying it will kill you but will make you feel like you have the flu, headaches etc. I had metal fume poisioning 1 time this year and it SUCKED!
yeah I read about it, ashamed I didn't know but glad I do now! Thanks for mentioning
 

alvin l nunley

Premium User
I get the same compression ratio in my spreadsheet, but I was wondering, with that gasket thickness and that deck height, isn't that a little thin?
 

Kart43

Member
Yes with details the compression ratio is correct we did not have all the details to verify.
Welding on galvanized and metals that have been cleaned with brake cleaner are extremely dangerous, and are to be avoided at all cost unless you are properly protected.
 

Lykkan

Member
was going to buy a timing key but figured I'd just make one, shaved off .048"
Yes with details the compression ratio is correct we did not have all the details to verify.
Welding on galvanized and metals that have been cleaned with brake cleaner are extremely dangerous, and are to be avoided at all cost unless you are properly protected.
if you're welding with argon + brake fluid, that's when you can get phosgene gas, with just 4 parts per million, it can kill you apparently. Crazy
 
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