Why is this such a slug without the spray?
It's not these cam specs 236/248@.50 113LSA .586" / .562" that are killing it. It is the overlap between the valves that will do it. If there is 16* of positive overlap then thats 100% the problem. Minirams no good either.
A have a gauge plumbed into the intake manifold, plus it matches the MAP sensor.
As far as boost/RPM: the boost climbs as the RPM climbs, I haven't really noticed it flatten out.
As far as boost/RPM: the boost climbs as the RPM climbs, I haven't really noticed it flatten out.
Originally Posted by RealQuick
Are you verifying boost with a gauge in the intake tract or are you quoting 11psi by the pulley ratio?
Originally Posted by 860 Performance
A have a gauge plumbed into the intake manifold, plus it matches the MAP sensor.
As far as boost/RPM: the boost climbs as the RPM climbs, I haven't really noticed it flatten out.
As far as boost/RPM: the boost climbs as the RPM climbs, I haven't really noticed it flatten out.
I disagree.
First off, a 236/246 is a pretty big cam.
Kiss, so what are you saying, that he would make more power with a smaller cam? Care to throw out a spec?
I made 73_rwhp with a 230/236//115 cam, but like I said before, it was a lot peakier of a cam than the current one.
I think this guy has a big cam, and a good longblock, and you would run a big cam like that to bring up your hp under the curve. A smaller cam with less overlap MIGHT make more peak hp but ask yourself, is 25rwhp more at peak faster or better than say someone who makes higher average hp from say 5000 to 7000 rpms? The school of thought for big racier cams is to bring up av. hp so that when the rpms drop back on shifts you are still dropping to a point where you make killer power.
So if someone makes 770rwhp but at 7000, and on shifts they drop back down to 5000, where they make 650rwhp, they are not necessarily faster.
But I think this guy has a problem elsewhere, he should make over 500rwhp, maybe 550rwhp. Check the belt my man.
First off, a 236/246 is a pretty big cam.
Kiss, so what are you saying, that he would make more power with a smaller cam? Care to throw out a spec?
I made 73_rwhp with a 230/236//115 cam, but like I said before, it was a lot peakier of a cam than the current one.
I think this guy has a big cam, and a good longblock, and you would run a big cam like that to bring up your hp under the curve. A smaller cam with less overlap MIGHT make more peak hp but ask yourself, is 25rwhp more at peak faster or better than say someone who makes higher average hp from say 5000 to 7000 rpms? The school of thought for big racier cams is to bring up av. hp so that when the rpms drop back on shifts you are still dropping to a point where you make killer power.
So if someone makes 770rwhp but at 7000, and on shifts they drop back down to 5000, where they make 650rwhp, they are not necessarily faster.
But I think this guy has a problem elsewhere, he should make over 500rwhp, maybe 550rwhp. Check the belt my man.
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Originally Posted by 860 Performance
Wow, thoes are some serious numbers with a kinda-similar cam....huh
Well, its easy enough to increase boost. I'm not getting belt slip, but it has a monster pulley on the blower, so thats why its only producing 11 psi. I had called paxton directly before about getting a smaller pulley, but they couldn't help me because its a custom set-up.
Anybody reccomened a place who could set me up with a pulley for the Novi?
Well, its easy enough to increase boost. I'm not getting belt slip, but it has a monster pulley on the blower, so thats why its only producing 11 psi. I had called paxton directly before about getting a smaller pulley, but they couldn't help me because its a custom set-up.
Anybody reccomened a place who could set me up with a pulley for the Novi?
Its a 10rib.
I'll give ASP a call, maybe I can get a toothed belt instead.
Monday I'm going back to the dyno and I'm going to go after the timing map. I'll post the results from that.
I'll give ASP a call, maybe I can get a toothed belt instead.
Monday I'm going back to the dyno and I'm going to go after the timing map. I'll post the results from that.
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Yes actually after re going over everything it's a blower setup, not a turbo setup so the overlap issue can be thrown out the window. and seeing as how pro stock john's is right around there with about 14 degrees i dont think that is the problem. I think there has to be a boost issue. Are you positive you're getting 11 lbs? Old plugs? wires? anything?? Something has to be wrong with the peripherals.
Nate
Nate
I am positive about the boost.
Everything like plugs and wires are good, anything like that would show up when I sprayed. It responded very well to the spray a clean 300hp shot.
I will scan the dyno sheet tonight, but I have no way to post it. I can email it anyone who wants to see it.
Everything like plugs and wires are good, anything like that would show up when I sprayed. It responded very well to the spray a clean 300hp shot.
I will scan the dyno sheet tonight, but I have no way to post it. I can email it anyone who wants to see it.
Originally Posted by taufern
Yes actually after re going over everything it's a blower setup, not a turbo setup so the overlap issue can be thrown out the window. and seeing as how pro stock john's is right around there with about 14 degrees i dont think that is the problem. I think there has to be a boost issue. Are you positive you're getting 11 lbs? Old plugs? wires? anything?? Something has to be wrong with the peripherals.
Nate
Nate
I'm sure it responded to a 300 shot. 
If I sprayed my engine with a 300 shot I would do 1000rwhp but you might need to wear protective gear during the dyno session.
860, I know other folks with blown LT1 and TPI setups, your numbers don't make sense. You have to figure out why. I know of stroker TPI's on motor making 350-375rwhp with those heads.
If I sprayed my engine with a 300 shot I would do 1000rwhp but you might need to wear protective gear during the dyno session.
860, I know other folks with blown LT1 and TPI setups, your numbers don't make sense. You have to figure out why. I know of stroker TPI's on motor making 350-375rwhp with those heads.
I run the newer style HEI distributor (not vac advance), which ties into my DFI. I checked it at idle to sync it up to the DFI.
Dosen't 22* sound real low for this combo? I'm guessing 27* would be a lot more like it, Mondays dyno trip will tell...
Dosen't 22* sound real low for this combo? I'm guessing 27* would be a lot more like it, Mondays dyno trip will tell...
Originally Posted by Pro Stock John
You running a distributor? MSD box? Are you sure on your timing?
I doubt 5 more degrees of timing will net 150rwhp more.
I think you need to think about what power level you should hit at that boost level given the parts you have. Then you can poke around and check stuff.
My ideas are:
-belt slippage
-trans slippage (big converter?, or bad trans)
-your timing is not right
-loss of ignition in higher rpms
-fuel pressure problem
If I had a lockable 700R4 instead of my T400 I would hit almost 800rwhp.
I think you need to think about what power level you should hit at that boost level given the parts you have. Then you can poke around and check stuff.
My ideas are:
-belt slippage
-trans slippage (big converter?, or bad trans)
-your timing is not right
-loss of ignition in higher rpms
-fuel pressure problem
If I had a lockable 700R4 instead of my T400 I would hit almost 800rwhp.
i would have to agree alot on what Johns Saying if his overlap was a problem it would show in him boosting. with that cam you chould make around 350-370rwhp at 10 compression, your running at 8 and only pushing 11psi, you slugishness is well b/c of the low compression ,low boost and mild overlap. your power will be high. you not losing power b/c and any of these just making it high in the power band, i say it's either your blower is maxing out or getting out of it's effiency level, your pulley is not big enough, you should be atleast at 15lbs with what say 24-26* timing guys? or yeah ur belt is slipping, or something along the lines of what other problems John mentioned.
I dont see overlap ever being a problem, just need a better bigger blower, and the less streetable it will be, and more race-only ready it will become.
I dont see overlap ever being a problem, just need a better bigger blower, and the less streetable it will be, and more race-only ready it will become.
Well, work up a list and check out different things.
When I had too large of a converter my numbers were down. But there are like 5-6 things that could cause you to make low power. I didn't even list internal engine issues.
When I had too large of a converter my numbers were down. But there are like 5-6 things that could cause you to make low power. I didn't even list internal engine issues.
