307 to 403 OLDS

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Oct 14, 2008
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Other than shorter pushrods and the thrust button, besides cost, a roller is a straight forward swap. I believe Lunati offers that 204/214 cam on a 112 LSA vs the 114 LSA. I had those Melling and the Edelbrock cams in my 403. I picked up the Edelbrock used with a bunch of parts, so the Melling ended up in my truck with the 350 the first time I pulled down the 403. I had 140 to 155 psi compression with that Edelbrock cam in my 8 to 1 403 and 140 to 142 psi on my awesome shape 76 Olds 350 with its factory high 7's to 1. So any octane can be used and get aggressive on part throttle timing. Aim for 36 to 40 total on the street without vacuum advance. I always found 36 total fastest at the track but 38 to 40 on a low compression Olds felt better, seat of the pants.
 
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TURNA

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Jul 24, 2009
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I would love a roller $$$$ and the ones I am seeing are 15/1800to 6000 power range .

Needs a convertor blah blah blah

I dont want that.

This is a stock rebuild 403 with just a little cam thorson shorty headers and thats it


If you guys see a roller that is 1000-5500 stock (D5) convertor please post it up!!
 
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TURNA

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Jul 24, 2009
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OOFA!!!!!!!! thats twice as much as the engine!!!!!!!!!!!!!!
 
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TURNA

Rocket Powered Basset Hound
Jul 24, 2009
10,941
19,992
113
Socialist NY
Other than shorter pushrods and the thrust button, besides cost, a roller is a straight forward swap. I believe Lunati offers that 204/214 cam on a 112 LSA vs the 114 LSA. I had those Melling and the Edelbrock cams in my 403. I picked up the Edelbrock used with a bunch of parts, so the Melling ended up in my truck with the 350 the first time I pulled down the 403. I had 140 to 155 psi compression with that Edelbrock cam in my 8 to 1 403 and 140 to 142 psi on my awesome shape 76 Olds 350 with its factory high 7's to 1. So any octane can be used and get aggressive on part throttle timing. Aim for 36 to 40 total on the street without vacuum advance. I always found 36 total fastest at the track but 38 to 40 on a low compression Olds felt better, seat of the pants.


Did you like them???

Did you see an improvement with them???
 

TURNA

Rocket Powered Basset Hound
Jul 24, 2009
10,941
19,992
113
Socialist NY
307 and 403 use the same timing pointer????
 
Oct 14, 2008
8,823
7,775
113
Melville,Saskatchewan
Did you like them???
Did you see an improvement with them???
Yes, anything is better than the 186/200 .400/.402 stock cam. Supposedly a single pattern is better. I currently have a 214/214 .472/.472 on a 110 LSA Erson custom from Cutlassefi. I like it OK, was way better with a 2300 flash stall, rated a 2200 to 2500, 1/4 block one wheel burnouts even with the 2.78 gears. The current 1700 rpm stall and 2.78 gear combo blows, no wheel spin on launch. My custom cam is very similar to the Erson TQ20 214/214 .478/.478 on a 111 LSA. The larger Lunati High Efficiency series 210/210 .470/.470 on a 110 LSA could also work. You will want at least a 2000 stall converter for fun launches.
307 and 403 use the same timing pointer????
Yes
 

TURNA

Rocket Powered Basset Hound
Jul 24, 2009
10,941
19,992
113
Socialist NY
All the other cams i am seeing say they need an adjustable valve train did you change yours
 
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