RenegadRomeo
Member
Gents I installed a hemi predator 212 this weekend - I'm totally lost ( I think ) idk.....
So my previous setup was - non hemi predator 212 - pvl flywheel - weenie pipe - top plate - fuel pump. Everything else is stock ( stock predator class ).......
I paired the engine with a 12 tooth clutch - 65 outback..... This has worked nicely for us ( won our first night out...
12/65 = 5.42 gear ratio......
Our next time out I bumped the gearing to - 13/71 = 5.46.
We ran good with this - 2nd in heat and feature..... Less bogging - engine stayed high in RPMs but never over revved....... I felt as if I was on the very edge.....
So the next weekend I ordered 11 tooth driver and 60th sprocket..... 5.45 gearing - I also went up a 1/2 in size on both rear tires....
We rained out for 4 weeks straight - Durning our down time a friend talked me into dropping on a brand new hemi....... Swears the hemi make more power.
This seems to be the point everything went wrong......
So this last Saturday - rain stayed away and we showed up with a brand new hemi.....
With the 11/60 gear installed - we went out for hotlaps..... Right away I notice the engine is floating valves at the very end of the straight away..... No mistaken - gearing was wrong......
Went into the pits and did a fast gear swap - back to what we know works ( 12/65 )....... Went back out for hotlaps and still had the issue - but not as bad......
I get back to the pits and at this point I'm thinking I have a running condition - not a gearing issue....... These are the same engines from what I understand the hemi just flows better........ At this point I'm scrambling trying to figure out the issue....... Not gonna name a name but someone at the track ( you would think ) knows what they are doing - told me to go up a gear size in the rear ( 3 tooth )....... Went out for the heat race with a 12/67 - same issue....... Engine would top at about 5200 rpms.....
We won our heat and believe it or not put some decent ground on the other drives......
Once again I'm in the pits....... This time changing plugs - coils - so on...... Again ( one of the top people tell me ) go up a gear or two more..... ( I went to a 70 in the rear )....
A main comes - it engine is worse then it has been all night..... Engine starter over revving mid straightaway... it took everything I had to keep my lead - all I could do is hold the bottom line and not swing up high on the straightaways........ It worked but I'm telling you - they wear all over me - any mistake and it would have been over..... Even tho we won...... I was cursing from the moment I took the checkered to the scale house - to my pit.....
All I could think was ( this motor is trash )...... After loading up and heading all I called a friend ( Chris cooper ) ( he is on here with us )......... After talking with him - turns out I was going the wrong way with the rear gear...... Should have been going down in size....... In my defense - I was told to go up..... However..... I'm very disappointed in how this weekend turned up - I should have known better - in fact I did know better but somehow it all got away from me......
Now that I know wear I went wrong....... One thing still bothers me.......
The 12/65 works perfect on our non hemi engine - but is not enough for our hemi engine..... Is there that much difference between the two - has anyone swapped between a non hemi and a hemi? The non hemi appears to be able to hold higher RPMs vs the hemi...... I would have thought the exact opposite....... Does my hemi engine have some kinda issue? Anyone else experience this?
also after running the engine in such a manner - should I junk it. Should I rebuild it....... I was advised to just change valve springs and it will probably be ok..... But idk I'm kinda uncomfortable running a engine that ways abused in such manor...... Thought and opinions please! Thanks all!
So my previous setup was - non hemi predator 212 - pvl flywheel - weenie pipe - top plate - fuel pump. Everything else is stock ( stock predator class ).......
I paired the engine with a 12 tooth clutch - 65 outback..... This has worked nicely for us ( won our first night out...
12/65 = 5.42 gear ratio......
Our next time out I bumped the gearing to - 13/71 = 5.46.
We ran good with this - 2nd in heat and feature..... Less bogging - engine stayed high in RPMs but never over revved....... I felt as if I was on the very edge.....
So the next weekend I ordered 11 tooth driver and 60th sprocket..... 5.45 gearing - I also went up a 1/2 in size on both rear tires....
We rained out for 4 weeks straight - Durning our down time a friend talked me into dropping on a brand new hemi....... Swears the hemi make more power.
This seems to be the point everything went wrong......
So this last Saturday - rain stayed away and we showed up with a brand new hemi.....
With the 11/60 gear installed - we went out for hotlaps..... Right away I notice the engine is floating valves at the very end of the straight away..... No mistaken - gearing was wrong......
Went into the pits and did a fast gear swap - back to what we know works ( 12/65 )....... Went back out for hotlaps and still had the issue - but not as bad......
I get back to the pits and at this point I'm thinking I have a running condition - not a gearing issue....... These are the same engines from what I understand the hemi just flows better........ At this point I'm scrambling trying to figure out the issue....... Not gonna name a name but someone at the track ( you would think ) knows what they are doing - told me to go up a gear size in the rear ( 3 tooth )....... Went out for the heat race with a 12/67 - same issue....... Engine would top at about 5200 rpms.....
We won our heat and believe it or not put some decent ground on the other drives......
Once again I'm in the pits....... This time changing plugs - coils - so on...... Again ( one of the top people tell me ) go up a gear or two more..... ( I went to a 70 in the rear )....
A main comes - it engine is worse then it has been all night..... Engine starter over revving mid straightaway... it took everything I had to keep my lead - all I could do is hold the bottom line and not swing up high on the straightaways........ It worked but I'm telling you - they wear all over me - any mistake and it would have been over..... Even tho we won...... I was cursing from the moment I took the checkered to the scale house - to my pit.....
All I could think was ( this motor is trash )...... After loading up and heading all I called a friend ( Chris cooper ) ( he is on here with us )......... After talking with him - turns out I was going the wrong way with the rear gear...... Should have been going down in size....... In my defense - I was told to go up..... However..... I'm very disappointed in how this weekend turned up - I should have known better - in fact I did know better but somehow it all got away from me......
Now that I know wear I went wrong....... One thing still bothers me.......
The 12/65 works perfect on our non hemi engine - but is not enough for our hemi engine..... Is there that much difference between the two - has anyone swapped between a non hemi and a hemi? The non hemi appears to be able to hold higher RPMs vs the hemi...... I would have thought the exact opposite....... Does my hemi engine have some kinda issue? Anyone else experience this?
also after running the engine in such a manner - should I junk it. Should I rebuild it....... I was advised to just change valve springs and it will probably be ok..... But idk I'm kinda uncomfortable running a engine that ways abused in such manor...... Thought and opinions please! Thanks all!