i was a 310 (n/a) before the MMR 290 block. then with the new block (10.5:1), longtubes and intake spacer i made.....312whp. But throw a ported blower with a lower pulley and give it hell
MMR Shortblock=Lost power???
- Thread starter SVTwnaRUN
- Start date
Could be a number of places to check
Belt slip?
Boost bypass?
Motor still tight from being new?
Dyno software updates or calibration changes between tunes?
All these things could lead to lower numbers
Take it to the track and see how it runs and go from there
Belt slip?
Boost bypass?
Motor still tight from being new?
Dyno software updates or calibration changes between tunes?
All these things could lead to lower numbers
Take it to the track and see how it runs and go from there
If you didnt have belt slip issues before you shouldnt have any now. Boost is a measure of restriction...you lost boost because the motor became more efficient. Even though you lost boost the motor is still moving the same amount of air but with less restriction. It should still make the same if not more power than before. If it was the same dyno in the same temperature and conditions as your previous numbers its possible that the cam timing is off. Who put the motor together? Were the cams degree'd or just installed by the timing marks?
Are both the dyno #s corrected?. to the same correction factor sae or std?. You would think it would at least make the same hp up top. just like when long tubes are installed most times you make less boost but still gain some hp. I would make sure your not slipping the belt and do a leak down just to make sure its ok which it probably is then at least port the blower and put a lower setup on it and throw some air thru the shortblock. Quick question did the last short block get hurt? just wondering why a killer shortblock and leave the unported stock supercharger. Also why go from 60s to 80s it would never need them with that eaton. If you want to make big hp its almost all gonna come from a bigger sc and more boost
Last edited:
I was told that the stock cams can't degree? We just had them set where the timing marks where... I will look in to a new belt and see if it helps on anything i currently have the gatorback belt but I think its time to replace bc its been used before.
Stock cams can be degreed.
Yes they can be, and also you should've grabbed some 96-98 cobra cams to put in. Cheap and decent gains
As to why you didn't have boost drop off before your new bottom end I don't know. You should have. But your stock eaton cannot handle that much PSI at 6000 rpms. I believe the eaton's efficiency ends at 4000 rpms @13lbs or so. Then when it hits 5800-6000rpm its max boost drops to 10.5 lbs. My termi does that exact thing currently. I will be sending my eaton to Posi performance for porting and it will be an easy and cheap(relative to buying an aftermarket blower) way to get all that HP back that I am missing from the infamous boost drop off.
I highly recommend getting with Posi performance or Steggy and have your eaton ported. You will definitely be happy after that.
I highly recommend getting with Posi performance or Steggy and have your eaton ported. You will definitely be happy after that.
- Joined
- Feb 28, 2007
- Messages
- 19,524
Posi doesn't port anymore, so you're going to have to go with Steg.
WHAAAAA?!?!?!?!?!? That makes me very upset! Oh well. My point stands.
I been really thinking of porting it,but also thinking about the 2.9...today when I was going home I got into the hwy and some kid with a z06 c5? 2003 past me Flyn and I down shiften to 3rd and I felt like the belt spinning??? But then when to 4th asoon I pass him i let off smell like clutch with the spec 2+ .
If you have enough $$ for a built motor then why stick with an eaton. Get the 2.9. The majority of ported eaton owners ended up growing TS.
Whom told you the stock cams can't be degree'd. If you would've done a little research here you will find many posts that say you can. The best way to find out if both sides are close is to get a compression test. If one whole side of the engine is higher than the other side than you cam timing is off. If they are about the same than your cam timing is set about the same, doesn't mean it's timed correctly just that they are about the same. Cam timing could be costing you about 20hp or so. 97 cobra cams degree'd are worth about 40hp.
Clutch slipping could be your loss of hp.
Users who are viewing this thread
