Not getting the boost I should be getting.
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From: Mililani, Hi
Not getting the boost I should be getting. Need some help to figure out what is wrong with mt car. I just changed the pulley on my ATI from a 3.7 to a 3.4 (ati said it should give me 10#'s of boost). Went to the track last night and only seen 7#'s. I did tighten the belt once after a couple of days. The boost seems to rise to 7 and then stop there. I know going down the track I'm running really rich (A/F's are in the 10.8 and 10.9 range). Could this be a good reason? Or is it something to do with the SC?
was it really hot out? alot of times temp can screw around with things, hotter it is less oxygen per cubic foot of air etc... but i dont think that would drop you 3 lbs....maybe belt slipage?
Could be your heads. Boost is a measure of how well your motor flows. If the heads flow realy good you will see less boost but more power. The heads are a bottle neck and the more u open them up to a point the more air they will flow.
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From: Mililani, Hi
Could be your heads. Boost is a measure of how well your motor flows. If the heads flow realy good you will see less boost but more power. The heads are a bottle neck and the more u open them up to a point the more air they will flow.
Maybe it is the heads. But shouldn't I see alittle more boost with the smaller pulley than 1 PSI? I thought Patriots heads flowed good? But if they didn't I should see more boost too right? Bigger bottle neck....
I'm pretty sure the belt isn't slipping. The last time I tightened it down pretty tight. Belt could only turn about 100 degrees to the side.
Maybe it is the heads. But shouldn't I see alittle more boost with the smaller pulley than 1 PSI? I thought Patriots heads flowed good? But if they didn't I should see more boost too right? Bigger bottle neck....
I'm pretty sure the belt isn't slipping. The last time I tightened it down pretty tight. Belt could only turn about 100 degrees to the side.
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Watch the gauge if the needle looks to be bouncing at a certain point on the boost gauge, then you are seeing belt slip.....which it probably is especially on the ATI kit.
Which pulley set up are you running? Stock 6 rib ATI? 8 rib ATI upgrade?
If you are on the stock 6 rib from ATI good luck you are in a loosing battle.
If you want a great pulley set up, go with the SDCE set up. I have had no problems at all with their set up. Quite a few of us are running this set up with excellent results.
Or try the ATI 8 rib upgrade, I know that there are a few having great luck with this set up aswell.
Good luck.
J
Which pulley set up are you running? Stock 6 rib ATI? 8 rib ATI upgrade?
If you are on the stock 6 rib from ATI good luck you are in a loosing battle.
If you want a great pulley set up, go with the SDCE set up. I have had no problems at all with their set up. Quite a few of us are running this set up with excellent results.
Or try the ATI 8 rib upgrade, I know that there are a few having great luck with this set up aswell.
Good luck.
J
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I agree with frcefed98. Hey J!.
Anyways the SDCE is a great set-up and well worth the investment of change over. The most you would see with a .300" drop in pulley size on a stock cube motor is about 2-3 lbs of boost. With that in mind, your combo in mind (383 with good flowing heads) and if you have the stock ATI Crank pulley it may only be around 1 lb. BTW, If you have a 6 rib your pushing the envelope on the 3.4 SC pulley!
Anyways the SDCE is a great set-up and well worth the investment of change over. The most you would see with a .300" drop in pulley size on a stock cube motor is about 2-3 lbs of boost. With that in mind, your combo in mind (383 with good flowing heads) and if you have the stock ATI Crank pulley it may only be around 1 lb. BTW, If you have a 6 rib your pushing the envelope on the 3.4 SC pulley!
, I am just glad that I don't have to buy anymore belts, the one that came with the SDCE kit is doing just fine
Myles, I agree with the SDCE also, as in the emails I sent you before 
I honestly think its more belt slippage, and possibly some clamps needing to be changed to a t bolt style than heads flow or anything else.
OT- Big Mahalo's to WS-6_2002 and Drew778 for installing my heads Thanksgiving since I am deployed. Much love my BK Brother.
I honestly think its more belt slippage, and possibly some clamps needing to be changed to a t bolt style than heads flow or anything else. OT- Big Mahalo's to WS-6_2002 and Drew778 for installing my heads Thanksgiving since I am deployed. Much love my BK Brother.
I'm guessing he is running the 6rib setup,since a 3.4 pulley size on a 8 rib ATI pulley setup would be 14-16lbs of boost.
Ditch the 6rib and go with an 8 rib setup.A D1 put's too much strain on that small 6rib setup.
Ditch the 6rib and go with an 8 rib setup.A D1 put's too much strain on that small 6rib setup.
Also brace the bracket somehow....the ATI s/c bracket flexes a lot. I have a stock warped one that can prove it.
The SDCE kit comes with a bracket brace, small but effective as the bracket doesn't flex anymore.
I also have a automotion steel s/c bracket too.....can never have too much strength
The SDCE kit comes with a bracket brace, small but effective as the bracket doesn't flex anymore.
I also have a automotion steel s/c bracket too.....can never have too much strength
frcefed98- Didnt you see a boost increase swapping out the twin IC for the OBX? If I recall a lot of ppl were getting gains, boost as well as power output from a FMIC over the twins. Something else to spend some $ on Myles!
Originally Posted by Mike2002
Where to get the SDCE kit?
Go to Google and do a search for SDCE.... or SD Concepts..... the link is there and they run about $700 fo rthe whole 8 rib setup...... i love mine and will never look back.......................
Kyle
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From: Mililani, Hi
I'm not sure where to get the SDCE kit? How much is it? I have plans in the future to change to bigger injectors. Trying to fix one problem at a time. The list is getting long... I don't notice any needle twitching going down the track. it kinda hits 7 and stays there. Yes I am running the 6 rib kit. I got jipped when I bought it. I was told by ATI it came standard. When I go the kit I called them and they told me its an extra add on. (more money).
Sent you an Email, I used Kyles info from above, Google is search persons best friend!
Let me know when you get the 60# Motrons, I can pick up your 42#ers
You really didnt get too jipped, free labor
Let me know when you get the 60# Motrons, I can pick up your 42#ers
You really didnt get too jipped, free labor