help with lq4 swap

[beeterolds]

If you live in a strict emissions testing area, a carb conversion on a LS won't pass testing. Factory LS cams aren't really suited for carbs anyway with their wide lobe center angle which is true of any EFI cam. Best way to go is pull everything from the donor car, or even buy a donor car to pull everything out of.

O ya? ever look at the factory L98 camshafts? Wide LCA I have one laying around its 115 or 116 I cant recall. They stuck em in 350 interceptor motors that had a carb perched on top.. I run a nice and wide 117 degree LCA cam.. Nothing but great fuel economy, smooth idle and a wide power band.. Whats the worst thing that can happen he changes the cam to maximize his gains?

 

[Brother Al]

Getting Waay off topic, but beeterolds, you are wrong about:

They stuck em in 350 interceptor motors that had a carb

The '86-88 9C1 Police Package Caprice used the LB4 TBI 4.3L V6 and LM1 E4ME Qjet 5.7L. They had their own specific camshaft profiles, not recycled out of the GM parts bin. The 9C1 LM1 did NOT use an L98 camshaft profile.... Actually, L98 camshaft profiles changed almost every year. Those L98 profiles also differed between the automatic and T-5 equipped '87-'92 F-Body and those were different from the automatic and manual-equipped '85-91 Corvette L98 cam profiles... also, for performance and emissions purposes, its likely the 9C1's had their own unique profile because of their heavy duty usage and heavier weight with police equipment installed...I'd have to search my cam profile notes to give specific numbers. I can assure you that those L98 cams were NEVER put into any '86-88 9C1 Police Package 350 LM1. Like the L69 305 and C/K Truck and G Van LM1 350 engines, they were not roller cam engines and the '87-92 L98 was a roller cam engine...

However, later variants of the LB9/L98 cam profiles were used in the '89-93 9C1 Police Duty LO3 TBI 305 & LO5 TBI 350, (which are roller cam engines). The only camshaft that I am aware of being "shared" by a Qjet engine and a TPI engine was the '85 LB9 TPI 305 & '85 L69 E4ME 305... Chevy took the potent L69 shortblock and dropped the TPI system onto it... in '86, they changed the LB9 cam to its own special EFI-happy but weaker profile, hence the power drop for '86.

 

[Clone TIE Pilot]

Yep, EFI and carburetors have different cam requirements as do different intake manifold designs. Alot of things affect what the best cam is going to be.

 

[beeterolds]

Getting Waay off topic, but beeterolds, you are wrong about:

They stuck em in 350 interceptor motors that had a carb

The '86-88 9C1 Police Package Caprice used the LB4 TBI 4.3L V6 and LM1 E4ME Qjet 5.7L. They had their own specific camshaft profiles, not recycled out of the GM parts bin. The 9C1 LM1 did NOT use an L98 camshaft profile.... Actually, L98 camshaft profiles changed almost every year. Those L98 profiles also differed between the automatic and T-5 equipped '87-'92 F-Body and those were different from the automatic and manual-equipped '85-91 Corvette L98 cam profiles... also, for performance and emissions purposes, its likely the 9C1's had their own unique profile because of their heavy duty usage and heavier weight with police equipment installed...I'd have to search my cam profile notes to give specific numbers. I can assure you that those L98 cams were NEVER put into any '86-88 9C1 Police Package 350 LM1. Like the L69 305 and C/K Truck and G Van LM1 350 engines, they were not roller cam engines and the '87-92 L98 was a roller cam engine...

However, later variants of the LB9/L98 cam profiles were used in the '89-93 9C1 Police Duty LO3 TBI 305 & LO5 TBI 350, (which are roller cam engines). The only camshaft that I am aware of being "shared" by a Qjet engine and a TPI engine was the '85 LB9 TPI 305 & '85 L69 E4ME 305... Chevy took the potent L69 shortblock and dropped the TPI system onto it... in '86, they changed the LB9 cam to its own special EFI-happy but weaker profile, hence the power drop for '86.

Sorry for the derailment brother AL but unless someone swapped cams which I doubt that's what I pulled out of mine...
I called up my friend In the parts dept. at Vandevere Chevy in Akron because I was wondering why I had a roller cammed 350 with a carb
and heres what he gave me
GM Part number 10066049
207/213
.415/.430
117LCA
Same if not similar cam they stuck in the L98. (or one of the variants) :shock: Just going with what I was told.

I also have plenty of pics to show you it IS a carbed roller motor.. Not to mention it has the L98 083 heads on it..

 

[Brother Al]

My apologies, I stand corrected on the use of roller blocks on 9C1 LM1 350's... after digging through my notes, I found two LM1 references I had jotted down long ago... one being Chevy's "Targetmaster 350" replacement and the other being the 9C1 Police/9C6 Taxi LM1 which started in '87 with a roller cam.

As for cam profiles, here's a list of the F Body camshafts.
1983 -'86 F-Body L69: GM PN: 14088843* Hyd. Flat Tappet - Duration @ .050": 202/206 - Max Lift: .403/.415 - 115 - Idle: 650 rpm (*Note: L69 cam is not the same as the L81 "929" cam.* GM Replacement PN: 12523897)
1985 F-Body LB9: GM PN: 14088843 Hyd. Flat Tappet - Duration @ .050": 202/206 - Max Lift: .403/.415 - 115 - Idle: 650 rpm
1986 F-Body LB9: GM PN: 14094097 Hyd. Flat Tappet - Duration @ .050": 178/194 - Max Lift: .350/.385 - 109 - Idle: 650 rpm
1987 F-Body LG4/LB9-AT: GM PN: 14093630 Roller Cam - Duration @ .050": ???/???- Max Lift: ???/??? - ???- Idle: 650 rpm
1987 F-Body LB9-T5: GM PN: 14093643 Roller Cam - Duration @ .050": 202/207 - Max Lift: .404/.415 114.5 - Idle: 650 rpm
1988 -'89 F-Body LB9-AT: GM PN: 10088155 Roller Cam - Duration @ .050": 179/194 - Max Lift: .350/.384 - 109 - Idle: 650 rpm
1988 -'89 F-Body LB9-T5: GM PN: 10066049 Roller Cam - Duration @ .050": 207/213 - Max Lift: .415/.430 - 117 - Idle: 650 rpm
1988 -'92 F-Body LO3: GM PN: 10088155 Roller Cam - Duration @ .050": 179/194 - Max Lift: .350/.384 - 109 - Idle: 650 rpm
1990 -'92 F-Body LB9/L98: GM PN: 10111773 Roller Cam - Duration @ .050": 202/207 - Max Lift: .413/.428 - 114.5 - Idle: 650 rpm