Has it ever run right? Do you know if it's tuned correctly? There are a lot of things that could be wrong. Don't just start throwing money and parts at it.
Super Jet Porting and polishing/compression
- Thread starter superjetchet21
- Start date
Has it ever run right? Do you know if it's tuned correctly? There are a lot of things that could be wrong. Don't just start throwing money and parts at it.
- Location
- Boynton Beach
Im sorry to get into your thread but it got me really interested. I purchased not long ago a BB engine from a reputable builder ported by another reputable builder. Motor did not run right so I measured the squish and compression (with snap-on) and turned out to be 220 on 36 domes and almost no squish under .0030. I put additional base gasket and squish came to .0042-.0045 which supposedly is in the proper range. However the compression was still too high - 205.
My question is: since I added an additional gasket and raised the top, therefore the porting, does that make a critical difference for the performance of the engine?
Also, since crank compression is irrelevant to the real compression when the engine is working, whats the whole purpose of measuring the crank comp at all?
The motor still does not feel as what I expected from a BB. I am in process of changing from dual 38s to single 48 Novi just for the sake of the experiment.
Thanks to all in advance for sharing your knowledge
.
D.
My question is: since I added an additional gasket and raised the top, therefore the porting, does that make a critical difference for the performance of the engine?
Also, since crank compression is irrelevant to the real compression when the engine is working, whats the whole purpose of measuring the crank comp at all?
The motor still does not feel as what I expected from a BB. I am in process of changing from dual 38s to single 48 Novi just for the sake of the experiment.
Thanks to all in advance for sharing your knowledge
.D.
A lot depends on who built it. I've been on a few engines and the performance can vary greatly. It's more than porting, it's fitting the rest of it together, too.
In your case, I find it curious that it was built by one guy and ported by another.
Lastly, dual 38's are nice and linear, but imho they are linear because they choke off some performance.
In your case, I find it curious that it was built by one guy and ported by another.
Lastly, dual 38's are nice and linear, but imho they are linear because they choke off some performance.
- Location
- United States
I run the stock pump, It had a skat 13/16th in it I just changed to a hooker 10/16th just to try something different, It also has a tbm stuffer
- Location
- United States
No worries DMPUS this is what this site is for haha we all need help! And yeah Im putting the entire ski back together and letting one of my mechanics test and tune it for me I think that maybe half the battle. I was just trying to figure out the whole compression issues why I had it apart
Quinc
Buy a Superjet
- Location
- California
Did you figure it out?
