400 HSR Serpentine setup - What did I do wrong?
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
400 HSR Serpentine setup - What did I do wrong?
Hi Guys,
I've been getting my new 400SBC motor ready to drop into my TransAM and have hit a brick wall.
I bought a 87 350TBI motor specifically for the serpentine setup which came with all the bolts pulleys etc.
I've installed the water pump with no worries, and then started to try to attach the serpentine brackets and it was a VERY tight fit, but managed to get the 3 bolts on by tightening up 1/4 turn at a time.
I was worried about stripping bolts or cracking/warping the AFR heads, but it seems to have gone on.
Now the tension pulley is in the way of the throttle body and I'm at a loss.
I bolted the a/c serpentine bracket to the upper of the 2 bolt holes in the front of the block near the fuel pump plate, and the other 2 into the heads.
Is there a different bracket for TPI as opposed to TBI, or have i just done something really wrong?

Can anyone help?
I've been getting my new 400SBC motor ready to drop into my TransAM and have hit a brick wall.
I bought a 87 350TBI motor specifically for the serpentine setup which came with all the bolts pulleys etc.
I've installed the water pump with no worries, and then started to try to attach the serpentine brackets and it was a VERY tight fit, but managed to get the 3 bolts on by tightening up 1/4 turn at a time.
I was worried about stripping bolts or cracking/warping the AFR heads, but it seems to have gone on.
Now the tension pulley is in the way of the throttle body and I'm at a loss.
I bolted the a/c serpentine bracket to the upper of the 2 bolt holes in the front of the block near the fuel pump plate, and the other 2 into the heads.
Is there a different bracket for TPI as opposed to TBI, or have i just done something really wrong?

Can anyone help?
Joined: Jan 2005
Posts: 10,430
Likes: 500
From: Hurst, Texas
Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Re: 400 HSR Serpentine setup - What did I do wrong?
Hi Guys,
I've been getting my new 400SBC motor ready to drop into my TransAM and have hit a brick wall.
I bought a 87 350TBI motor specifically for the serpentine setup which came with all the bolts pulleys etc.
I've installed the water pump with no worries, and then started to try to attach the serpentine brackets and it was a VERY tight fit, but managed to get the 3 bolts on by tightening up 1/4 turn at a time.
I was worried about stripping bolts or cracking/warping the AFR heads, but it seems to have gone on.
Now the tension pulley is in the way of the throttle body and I'm at a loss.
I bolted the a/c serpentine bracket to the upper of the 2 bolt holes in the front of the block near the fuel pump plate, and the other 2 into the heads.
Is there a different bracket for TPI as opposed to TBI, or have i just done something really wrong?

Can anyone help?
I've been getting my new 400SBC motor ready to drop into my TransAM and have hit a brick wall.
I bought a 87 350TBI motor specifically for the serpentine setup which came with all the bolts pulleys etc.
I've installed the water pump with no worries, and then started to try to attach the serpentine brackets and it was a VERY tight fit, but managed to get the 3 bolts on by tightening up 1/4 turn at a time.
I was worried about stripping bolts or cracking/warping the AFR heads, but it seems to have gone on.
Now the tension pulley is in the way of the throttle body and I'm at a loss.
I bolted the a/c serpentine bracket to the upper of the 2 bolt holes in the front of the block near the fuel pump plate, and the other 2 into the heads.
Is there a different bracket for TPI as opposed to TBI, or have i just done something really wrong?

Can anyone help?
Supreme Member
iTrader: (13)
Joined: Dec 2002
Posts: 2,535
Likes: 17
From: Bowdon, GA.
Car: 1988 Camaro
Engine: 355, 10.34:1, 249/252 @.050", IK200
Transmission: TH-400, 3500 stall 9.5" converter
Axle/Gears: Ford 9", detroit locker, 3.89 gears
Re: 400 HSR Serpentine setup - What did I do wrong?
Yep, I agree. Looks like it came from a truck/suv. The truck brackets are taller and will not work on a third gen.
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Re: 400 HSR Serpentine setup - What did I do wrong?
****!
Am i able to modify them at all?
It's about a 1/4" out on the bottom block bolts so can i drill them out?
The a/c bracket still needs the further right'est bolt needs to be braced to something, but buying a serp setup from the states and shipping it to Australia is not going to be possible with my budget.
Any other options I have?
Am i able to modify them at all?
It's about a 1/4" out on the bottom block bolts so can i drill them out?
The a/c bracket still needs the further right'est bolt needs to be braced to something, but buying a serp setup from the states and shipping it to Australia is not going to be possible with my budget.
Any other options I have?
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Re: 400 HSR Serpentine setup - What did I do wrong?
I still don't get it, even if it was from a truck what difference does that make?
The physical dimensions of a 350 from a truck will be the same as one from a car, the bolt holes should be in the same place on the heads and block.
I understand the clearance potential issue is there, but how does it not line up with the bolt holes?
FYI the P/N for the a/c bracket is 10118751.
The physical dimensions of a 350 from a truck will be the same as one from a car, the bolt holes should be in the same place on the heads and block.
I understand the clearance potential issue is there, but how does it not line up with the bolt holes?
FYI the P/N for the a/c bracket is 10118751.
Joined: Nov 2008
Posts: 2,100
Likes: 180
From: Milwaukee
Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: 400 HSR Serpentine setup - What did I do wrong?
I'm not sure what bolts aren't lining up on the block and heads or why, but does it really matter at this point if brackets won't clear the TB intake ducts anyway? You're still going to need Fbody accessories, now if they have a problem bolting up you'll need to figure out bolt hole modifications.
Trending Topics
Joined: Jan 2005
Posts: 10,430
Likes: 500
From: Hurst, Texas
Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Re: 400 HSR Serpentine setup - What did I do wrong?
I'm not sure what bolts aren't lining up on the block and heads or why, but does it really matter at this point if brackets won't clear the TB intake ducts anyway? You're still going to need Fbody accessories, now if they have a problem bolting up you'll need to figure out bolt hole modifications.
He can also use the serpentine setup from a B/D-car TBI engine.
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Re: 400 HSR Serpentine setup - What did I do wrong?
Again very rare in Australia unfortunately.
As I said above, if I move the bracket over so only one of the 2 head bolts (the outer head bolt) is used, I can attach the brace from the 3rd bracket mounting bolt hole to the exhaust stud using a space and that should provide enough stability yes?
Drilling the holes out on the bracket isn't a problem, it only needs slight adjustment to fit, and the belt should still fit with the tensioner extending out slightly more yes?
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Re: 400 HSR Serpentine setup - What did I do wrong?
I'd go back to a v-belt setup but the motor has already been balanced with the crank serp pulley
Joined: Sep 2005
Posts: 27,934
Likes: 2,454
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: 400 HSR Serpentine setup - What did I do wrong?
Pulley doesn't matter about balance. You can swap them all you want.
Supreme Member
iTrader: (13)
Joined: Dec 2002
Posts: 2,535
Likes: 17
From: Bowdon, GA.
Car: 1988 Camaro
Engine: 355, 10.34:1, 249/252 @.050", IK200
Transmission: TH-400, 3500 stall 9.5" converter
Axle/Gears: Ford 9", detroit locker, 3.89 gears
Re: 400 HSR Serpentine setup - What did I do wrong?
I think the bolts not lining up is the heads. The OP has AFR alum. aftermarket heads..
Most aftermarket heads are off just a tad. The bigger, better heads are really a tad wider than stock to fit the valves and chamber shape the use.
It is not uncommon for brackets not to line up dead on with aftermarket heads and even some aftermarket intakes.. Kind of common to have to drill the acc. bracket holes out a touch.
Most aftermarket heads are off just a tad. The bigger, better heads are really a tad wider than stock to fit the valves and chamber shape the use.
It is not uncommon for brackets not to line up dead on with aftermarket heads and even some aftermarket intakes.. Kind of common to have to drill the acc. bracket holes out a touch.
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Re: 400 HSR Serpentine setup - What did I do wrong?
I think the bolts not lining up is the heads. The OP has AFR alum. aftermarket heads..
Most aftermarket heads are off just a tad. The bigger, better heads are really a tad wider than stock to fit the valves and chamber shape the use.
It is not uncommon for brackets not to line up dead on with aftermarket heads and even some aftermarket intakes.. Kind of common to have to drill the acc. bracket holes out a touch.
Most aftermarket heads are off just a tad. The bigger, better heads are really a tad wider than stock to fit the valves and chamber shape the use.
It is not uncommon for brackets not to line up dead on with aftermarket heads and even some aftermarket intakes.. Kind of common to have to drill the acc. bracket holes out a touch.
Awesome, well that's one bit of good news.
I guess now I just need to find someone who has tried the bracing method with a truck setup and whether it's strong enough to hold or not....
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Re: 400 HSR Serpentine setup - What did I do wrong?
Is there a readily available throttle body elbow i could use?
Going from the twin 58mm throttle body to a LS1 MAF at 90degrees?
I could then pipe the throttle body to the filter and keep the truck brackets.
My mate is drilling out the brackets for me to take some of the tension off the bolts.
I'd rather not experiment with the bracing though and try to be able to have it bolted to the block and heads properly.
Anything available for it?
Going from the twin 58mm throttle body to a LS1 MAF at 90degrees?
I could then pipe the throttle body to the filter and keep the truck brackets.
My mate is drilling out the brackets for me to take some of the tension off the bolts.
I'd rather not experiment with the bracing though and try to be able to have it bolted to the block and heads properly.
Anything available for it?
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Re: 400 HSR Serpentine setup - What did I do wrong?
I found a $20 90degree silicone tube on ebay that looks like it should bypass it so I can use the truck brackets and hopefully it will clear the hood, it's lower than the TB on both sides with the accessories on, so here's hoping.
Otherwise I guess it's back to V-belt
Otherwise I guess it's back to V-belt
Joined: Sep 2005
Posts: 27,934
Likes: 2,454
Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: 400 HSR Serpentine setup - What did I do wrong?
The HSR is well and widely known not to clear a Firebird hood; some of them however will shut over it if some of the bracing is notched out.
Pretty sure there's no chance at all that the hood will close on those brackets. The HSR is parallel to the crank, and thus slopes upward toward the front, significantly; but the hood slopes down toward the front. The farther forward you go, the less space, vertically, there is.
Pretty sure there's no chance at all that the hood will close on those brackets. The HSR is parallel to the crank, and thus slopes upward toward the front, significantly; but the hood slopes down toward the front. The farther forward you go, the less space, vertically, there is.
Joined: Jul 1999
Posts: 12,096
Likes: 126
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Re: 400 HSR Serpentine setup - What did I do wrong?
Those are the same brackets I pulled out of a '95 GMC 3500 for my Corvette. They are quite tall, and about a half inch closer to the block than the fbody brackets.
-- Joe
-- Joe
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Re: 400 HSR Serpentine setup - What did I do wrong?
Hey Joe,
Does that mean they will fit but just closer to the bonnet?
If they fit in a corvette I'd assume they'll fit in an f-body
Does that mean they will fit but just closer to the bonnet?
If they fit in a corvette I'd assume they'll fit in an f-body
Joined: Jul 1999
Posts: 12,096
Likes: 126
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
Re: 400 HSR Serpentine setup - What did I do wrong?
But yes, they are closer to the hood or bonnet as you guys call it.

The tensioner is also in the way of the TB as you have found, but if you have a close radius elbow it should solve that.
A lot of guys also make adapters out of 3/8" sheet stock to relocate these brackets up, down, over, whatever they need or even to mount them on a BBC.
-- Joe
Joined: Mar 2017
Posts: 4,255
Likes: 427
From: Portland, OR
Car: 86 Imponte Ruiner 450GT, 91 Formula
Engine: 350 Vortec, FIRST TPI, 325 RWHP
Transmission: 700R4 3000 stall.
Axle/Gears: 9 Bolt Torsen 3.70
Re: 400 HSR Serpentine setup - What did I do wrong?
Thread Starter
Senior Member

Joined: Feb 2009
Posts: 874
Likes: 18
From: Brisbane, Australia
Car: 1985 Pontiac TransAM
Engine: 400SBC 24x conversion
Transmission: T700r Stage2 Shiftkitted
Axle/Gears: 2.77 9 Bolt
Re: 400 HSR Serpentine setup - What did I do wrong?
Yes you're very helpful aren't you?
As already mentioned you've dug up a 4 year old thread to throw shade instead of offer assistance.
I ended up buying another set of TPI brackets from the states, but being in Australia I was looking for a less costly alternative than shipping heavy brackets overseas.
Just crawl back under your bridge and wait for the next redundant post to jump out at.
Senior Member
Joined: Mar 2017
Posts: 902
Likes: 139
From: waterloo ontario
Car: 1986 trans am
Engine: 305/350
Transmission: 5 speed
Axle/Gears: 3.27
Re: 400 HSR Serpentine setup - What did I do wrong?
my apologies,i was having a very bad week.hopefully you got it all sorted out.did you have a chance to see cleetus mcfarland's "toast" the supercharged third gen camaro at the summernats in Australia? he didn't do too well compared to the veterans,blew up on the first skid(then reinstalled a new engine that was shipped over to Australia) but it was cool to see a third gen down under "trying" to compete with the worlds greatest burnout kings.
Thread
Thread Starter
Forum
Replies
Last Post
philly5eagle
Engine/Drivetrain/Suspension Wanted
6
Apr 21, 2012 08:32 PM












