# 91 305 engine ? **URL:** \ **Category:** PittSpeed Automotive\ **Created:** [April 20, 2007, 2:45pm UTC](https://forums.speedlife.net/t/91-305-engine/189411 "2007-04-20T14:45:13Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![neonracer01](https://avatars.discourse-cdn.com/v4/letter/n/9fc348/32.png) [@neonracer01](https://forums.speedlife.net/u/neonracer01)\ **Post date:** [April 20, 2007, 2:45pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/1 "2007-04-20T14:45:13Z")
can a 91 305 engine that has the throttle body be changed over to run a carb and edlebrock 2101 intake? its the 86 and ealier intake. ---
**Author:** ![Quik83Z](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/quik83z/32/6042_2.png) [@Quik83Z](https://forums.speedlife.net/u/Quik83Z)\ **Post date:** [April 20, 2007, 3:23pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/2 "2007-04-20T15:23:52Z")
I believe you need the Edelbrock 2104 for a 86-92 SBC. They changed the angle on the center intake bolts. [http://store.summitracing.com/partdetail.asp?part=EDL-2104&autoview=sku](http://store.summitracing.com/partdetail.asp?part=EDL%2D2104&autoview=sku) ---
**Author:** ![neonracer01](https://avatars.discourse-cdn.com/v4/letter/n/9fc348/32.png) [@neonracer01](https://forums.speedlife.net/u/neonracer01)\ **Post date:** [April 20, 2007, 3:25pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/3 "2007-04-20T15:25:25Z")
could i just change the heads to the old style? ---
**Author:** ![Orr89rocz](https://avatars.discourse-cdn.com/v4/letter/o/ac91a4/32.png) [@Orr89rocz](https://forums.speedlife.net/u/Orr89rocz)\ **Post date:** [April 20, 2007, 3:25pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/4 "2007-04-20T15:25:55Z")
yes it should have centerbolt heads which will need 87 up intakes. but not 100% sure on the TBI cars. think so but check to see if your valve covers are center bolted and yes change the heads it should work fine ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [April 20, 2007, 3:26pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/5 "2007-04-20T15:26:03Z")
> [@13005TEDGP\>\*neonglh-Roll](https://forums.speedlife.net/t/13005tedgp-neonglh-roll/29589/18): > > I believe you need the Edelbrock 2104 for a 86-92 SBC. They changed the angle on the center intake bolts. > > [http://store.summitracing.com/partdetail.asp?part=EDL-2104&autoview=sku](http://store.summitracing.com/partdetail.asp?part=EDL%2D2104&autoview=sku) Same as I thought. What if he would use a set of older style heads? Doesn’t the 2nd gen blocks flow water in reverse? Would that be an issue with the older heads? ---
**Author:** ![Orr89rocz](https://avatars.discourse-cdn.com/v4/letter/o/ac91a4/32.png) [@Orr89rocz](https://forums.speedlife.net/u/Orr89rocz)\ **Post date:** [April 20, 2007, 3:27pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/6 "2007-04-20T15:27:34Z")
LT1 was 93+ which was reverse cooled… i dont think there is any difference from 86 previous heads to the 87 up heads other than bolt hole angles and centerbolt valve covers ---
**Author:** ![Quik83Z](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/quik83z/32/6042_2.png) [@Quik83Z](https://forums.speedlife.net/u/Quik83Z)\ **Post date:** [April 20, 2007, 3:28pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/7 "2007-04-20T15:28:09Z")
86 through 92 are still 1st gen SBC. 2nd gen started with the LT1 in 1993. Yes, he could change the heads to earlier heads then the 2101 would fit. ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [April 20, 2007, 3:29pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/8 "2007-04-20T15:29:08Z")
> [@How would you go about diagnosing this problem...](https://forums.speedlife.net/t/how-would-you-go-about-diagnosing-this-problem/29575/22): > > LT1 was 93+ which was reverse cooled… i dont think there is any difference from 86 previous heads to the 87 up heads other than bolt hole angles and centerbolt valve covers Looks like your getting a 305 with old heads… ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [April 20, 2007, 3:30pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/9 "2007-04-20T15:30:38Z")
> [@5/20 Nyspeed BBQ @ Chestnut Ridge \*\*PAYMENT INFO INSIDE\*\*](https://forums.speedlife.net/t/5-20-nyspeed-bbq-chestnut-ridge-payment-info-inside/24869/491): > > 86 through 92 are still 1st gen SBC. 2nd gen started with the LT1 in 1993. > > Yes, he could change the heads to earlier heads then the 2101 would fit. I didn’t relize that. I thought 87 started the 2nd gen. THanks for the info. did anything other than the rear main chance in 87? ---
**Author:** ![Quik83Z](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/quik83z/32/6042_2.png) [@Quik83Z](https://forums.speedlife.net/u/Quik83Z)\ **Post date:** [April 20, 2007, 3:33pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/10 "2007-04-20T15:33:42Z")
Factory hydraulic roller cams debuted in 1987 as well. ---
**Author:** ![Orr89rocz](https://avatars.discourse-cdn.com/v4/letter/o/ac91a4/32.png) [@Orr89rocz](https://forums.speedlife.net/u/Orr89rocz)\ **Post date:** [April 20, 2007, 3:39pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/11 "2007-04-20T15:39:47Z")
yep 87 was roller cams, 1 pc rear main seals, different intake/head bolt holes ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [April 20, 2007, 3:42pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/12 "2007-04-20T15:42:44Z")
Not that I don’t believe you guys, but why is it when I hit the advance auto web page, it tells the water pump for a 1991 firebird 5.0L is a reverse rotation pump? ---
**Author:** ![Quik83Z](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/quik83z/32/6042_2.png) [@Quik83Z](https://forums.speedlife.net/u/Quik83Z)\ **Post date:** [April 20, 2007, 3:44pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/13 "2007-04-20T15:44:04Z")
Serpentine drive requires reverse rotation water pump. Standard belt drive requires forward rotation water pump. It all depends on the drive system. Serpentine belt loops back around the top of the pump requiring a reverse rotation pump. ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [April 20, 2007, 3:50pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/14 "2007-04-20T15:50:39Z")
> [@How would you go about diagnosing this problem...](https://forums.speedlife.net/t/how-would-you-go-about-diagnosing-this-problem/29575/23): > > Serpentine drive requires reverse rotation water pump. Standard belt drive requires forward rotation water pump. It all depends on the drive system. Serpentine belt loops back around the top of the pump requiring a reverse rotation pump. Thanks. Was thinking that after posting, but firgued I would wait on the experts… ---
**Author:** ![neonracer01](https://avatars.discourse-cdn.com/v4/letter/n/9fc348/32.png) [@neonracer01](https://forums.speedlife.net/u/neonracer01)\ **Post date:** [April 20, 2007, 3:54pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/15 "2007-04-20T15:54:40Z")
> [@How would you go about diagnosing this problem...](https://forums.speedlife.net/t/how-would-you-go-about-diagnosing-this-problem/29575/23): > > Serpentine drive requires reverse rotation water pump. Standard belt drive requires forward rotation water pump. It all depends on the drive system. Serpentine belt loops back around the top of the pump requiring a reverse rotation pump. can i just eliminate the serpetine system and put my old belts on? will the water pump and alternater from the older style bolt on in place of the serpentine? ---
**Author:** ![yelo69](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/yelo69/32/6023_2.png) [@yelo69](https://forums.speedlife.net/u/yelo69)\ **Post date:** [April 20, 2007, 4:28pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/16 "2007-04-20T16:28:04Z")
> [@BUSTED! 142 MPH in 55 zone](https://forums.speedlife.net/t/busted-142-mph-in-55-zone/29605/27): > > can a 91 305 engine that has the throttle body be changed over to run a carb and edlebrock 2101 intake? its the 86 and ealier intake. Answer to your original question…yes the old style intake will work on TBI heads…you just have to egg out the 4 center holes…hope this helps. ---
**Author:** ![Quik83Z](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/quik83z/32/6042_2.png) [@Quik83Z](https://forums.speedlife.net/u/Quik83Z)\ **Post date:** [April 20, 2007, 4:45pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/17 "2007-04-20T16:45:19Z")
Your old water pump and alternator should bolt on but you will have to use all the associated bracketry that goes with them. Yeah, you can elongate the holes on an intake, but the bolt heads on the inner four bolt holes will not sit flat against the intake and could crack it. There are angled spacers available to take up the slack, but I don’t remember who makes them. ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [April 20, 2007, 4:52pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/18 "2007-04-20T16:52:11Z")
> [@Problems with ebay???](https://forums.speedlife.net/t/problems-with-ebay/29555/6): > > Your old water pump and alternator should bolt on but you will have to use all the associated bracketry that goes with them. Do you mean the bracketry that goes with the old equipment, or the bracketry from the new style motor? ---
**Author:** ![Quik83Z](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/quik83z/32/6042_2.png) [@Quik83Z](https://forums.speedlife.net/u/Quik83Z)\ **Post date:** [April 20, 2007, 6:31pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/19 "2007-04-20T18:31:51Z")
The bracketry should stay with the accessories, not the motor. Use the old stuff with the old alternator, water pump, power steering, etc. ---
**Author:** ![tom\_vito](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tom_vito/32/6000_2.png) [@tom\_vito](https://forums.speedlife.net/u/tom_vito)\ **Post date:** [April 20, 2007, 6:44pm UTC](https://forums.speedlife.net/t/91-305-engine/189411/20 "2007-04-20T18:44:07Z")
> [@Quik83Z"](#): > > The bracketry should stay with the accessories, not the motor. > > Use the old stuff with the old alternator, water pump, power steering, etc. Cool thanks for the info… [Next page](https://forums.speedlife.net/t/91-305-engine/189411.md?page=2)