cch

So if I'm reading correctly you're saying the single plain has a higher flow rating? In which case, yes it would make sense cause more air= more power. But, my cam runs out at 58 and unfortunately I'm beyond the point of changing it, it's gotta stay... so I wouldn't really be able to take advantage of a single plains high end..

Joel5.0

Don't take the following in a negative way, I just read your post regarding the little mishap with the HG's. IMO.... you are going to switch to a carburetor setup for the wrong reason, why?........... Are you 100% sure that change will solve the engine detonation problem?

If the answer starts with "Maybe...", "I've been told....".... don't do it. You could be using the wrong premise to justify an expenditure that will not solve that problem. A simple way to ID what is causing it with the EFI setup currently in the vehicle, is to set timing to ~25° - 30° initial, NOT install the SPOUT plug and test how it does.

BTW..... the advantage of a SP intake is not only limited to the high end.

cch

I was just planning on switching to carbed cause I've tried everything else I can think of and this is about the only thing left. I'm just tired of spending money, working on this damn thing and never being able to drive. To answer your question.. no I'm not 100% sure of anything... but I don't know what else to do.

Would you mind elaborating... as you can probably tell... I still have a lot to learn..

Thanks again

Joel5.0

Au contraire...... a carburetor setup is not the only thing left, as a matter of fact, it could make the problem worse if the cause is not EEC related. The reason why I posted the locked timing test (SPOUT removed) is to help you ID if it's an A/F or spark advance related issue....... which you should do to prevent you "throw a carburetor setup" and continue having the pre-detonation issue.

Regarding the SP intake...... everybody focuses on torque/HP graphs vs RPM...... even if torque/HP could be lower than a DP intake setup...... how fast does it make them is what really matters at the track or street, and the SP intake is one of the "tools" to accomplish just that. You're right though, since you have limited the combo with the cam, you need to crutch it by limiting the intake flow and use ~78% - 85% of what the TW's can contribute.

cch

I'll try the test tomorrow. I realize that removal of the spout will bipass the computer not allowing it to advance timing, but with the 25* set initial time won't that cause the motor to act horrendously? So pretty much I'm just looking to see if it still detonates.. If it doesn't, then it's a computer problem. If it does, then I'm back to square 1, correct? Thanks Joel.

Force4

i would say air gap + 700cfm or 750cfm. I am running 170cc edelbrock performer RPM's with a Edelbrock Air gap and a streefire 750cfm with 80mm secondary jets and the motor runs smooth as butter. ( I had a 650 and the motor seemed to gasp for air)

Joel5.0

25° is the starting point.... if it doesn't detonate, increase it to 28°, step and repeat to 30° if the results don't show any pre-det issues. BTW.... locking timing is a very old school trick at the track with EFI setups..... and it works.

mjr46

cch , do as joel states he is trying to isolate the problem down to a system which is what troubleshooting is all about, it will cost you no money to do as he states however the carb swap will cost you a bunch

cch

Oh I definitely will. But if it detonates at 25*+ then I'm back to square 1, if it doesn't well then I have a computer problem and then what? new computer, chip? well, atleast then I'd know it wasn't an internal problem at which point I'd still probably wanna switch over to carb rather then go through a tuning process which can't be done in my parts.

Oh just for curiosity's sake, Would I have any hood clearance issues with an rpm air gap?

Thanks guys!

mjr46

air gap will fit fine, I know it will...lol......anyway just go perform the test joel stated and lets not speculate or enter into hypothetical "what ifs"