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Discussion Starter · #1 · (Edited)
Cam Help Conclusion with Pics, Vid and a trophy

A friend has built a 383 in a 98 Corvette. The tuner has told him the car feels sluggish and he thinks the cam is too big for the intake and is keeping the car from reaching it's full potential. He's now wanting to get some input on specing a new cam for his setup that will give him the most potential. So for you cam gurus out there, give me/him some input. The engine specs are below. If you have any other questions ask away and I will answer.

383cu in
12:1 Compression
215cc Trick Flow heads
Fast 92 Intake
Ported LS2 Throttle Body
Cam Motion Solid Roller Cam, 256/264 .680/.680 110+4
Comp solid lifters
T&D shaft mount rockers
 

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Where and when does the car feel sluggish? My thought would be that it feels sluggish in the RPM range up to 2500 and thats just because that cams power band starts in the 2500 to 6800 range.
 

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Discussion Starter · #3 ·
Where and when does the car feel sluggish? My thought would be that it feels sluggish in the RPM range up to 2500 and thats just because that cams power band starts in the 2500 to 6800 range.
You're about right. I just found out he has yet to drive the car and is simply going on the tuners word. He lives in Nashville and the tuner is in Harrodsburg, KY. He has told him that up to 1500 it seems to stumble. My thought is that basically the cam is so big it's starving the engine for air. Some elsewhere have suggest a 102mm intake but I'm not sure how much more that would help. Some yes, but enough?
 

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Discussion Starter · #4 ·
I forgot to mention, the car does stumble a little bit up to the 1500 range but he said it actually felt sluggish across the entire RPM range.
 

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That is a rediculously big cam. It probably starts to hit the power band around 4500RPM, so anything < that would feel a bit week. Is this a race car i hope? A cam that big has no business on the street.
 

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yea, that cam is on the large side for a 383 ls1. Hell, the LG G5X4 is a good size cam for a 383 and it isn't nearly that big.
 

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Discussion Starter · #7 ·
Yep, it is a big cam:laughing:.

It is actually a car intended for the street that will see the strip from time to time. It's a completely stock bodied 98 C5 the only addition being a roll cage. He seems to have taken the opinion of "bigger is ALWAYS better" mentality. This time that's not quite the case though.

He has spoken today with Cam Motion and Comp both. He's speccing a cam with each of them that would be more in line with what it needs for the street. He's either going to go with one of those cams or with a new intake and the current cam.
 

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The big kill for him in his current cam is the 110 lsa. It makes it harder to deliver air to the cylinders at low RPM.
 

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If I were him I'd look for something around 240I and 246E, .612" with a 112* LSA. That will give him better manners, likely more total HP and a way better curve. That's still pretty darn big, but doable in a 383.
 

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Discussion Starter · #10 ·
Just an update to those who responded about this problem. It appears the problem was not actually in the cam itself. The reluctor wheel was 3deg off and was causing the engine power issues. Doing a few different things to the car at the moment. I'll post dyno figures once we get them. It may be near the end of the month though.:thumbsup:
 

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Discussion Starter · #11 · (Edited)
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