SDPC tpi and fastburn heads??
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Pro
Joined: Nov 1999
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From: Auburn Georgia
Cruise-In II Veteran
SDPC tpi and fastburn heads??
I have been looking at the SDPC tpi intake along with the aluminum fastburn heads and LT4 hot cam for my L98. SDPC claims 360 hp :D . Anybody have thoughts on or experience with this setup :confused:
Melting Slicks
Joined: Jun 2000
Posts: 3,215
Likes: 6
From: Tampa Florida
Re: SDPC tpi and fastburn heads?? (WINNER)
I thought the 360 HP version used the SDPC TPI intake, HOT cam, and the Vortec heads rather than the Fastburn models.
I would choose AFR's over Fastburns and not need the SDPC intake.
Good Luck!
I would choose AFR's over Fastburns and not need the SDPC intake.
Good Luck!
Drifting
Joined: Jul 2001
Posts: 1,418
Likes: 1
Re: SDPC tpi and fastburn heads?? (WINNER)
Yes I have done this.Without the Fast Burn Heads
1988 IROC with a 9.5-1 383,700r4 with stock stall and shift kit.2.77 gear w/245/50/16 TA Radials.Maf screen removed and adjustable FPR ,ported plenum.Stock runners.I used 24lb injectors and used the stock but modified cast iron exhaust manifolds" headers will not be considerd on this F Body".A Random Technologies single cat is used.
I port matched the manifold to fully ported iron Vortech heads with screw in studs and a spring upgrade plus I cut the guide bosses down and installed bronze guide liners..I worked the combustion chambers to obtain the 64cc volume that these heads are advertised at to help bring the compression to above specs.When I cc,d them they were 60cc.The cam is a Comp Xtreme Energy Flat Tappet Hydraulic XE 256 H "small base circle"that I had ground on 112 LSA instead of the 110 shelf grind.I degreed it to 5 degrees advanced. I used early style stamped steel 1.5 ratio rockers.I drilled a 0.60 hole in one of the throttle body blades"to get the idle down" and set the timing at 8 degrees but did not use an after market computer chip.
This is my son's car that ran a respectable 14.98 or so at 91-92 mph with 115k on the old 350.It used to burn the tires in first only to bog bad when it hit 2nd gear.Now it lights the tires in first and continues to burn to the top of 2nd.It runs to 5k rpm pretty well.It idles well and is noticeably louder at the muffler.I doubt he will get Street slicks and run it at the track until spring but I am guessing 13,s will not be a problem.We are not going to bother with a chip until this traction problem is cured.I chose this small cam because of the 2.77 gear.I think the next step up XE cam on a 114 lsa would work just as well in hind site but a chip change would probably have been needed.The torque is overkill right now.
All in all it is a fairly decent combo for the price as we were not trying to build it into a street killer however I have seen some draw backs that I will pass along.
1. I would not attempt to completely match the roof of the intake manifold to the heads.The raised roof design of the vortech head and the roof design of the manifold does not make for a good transition if matched completely.It is kind of like a V turned up side down and spread apart.The roof in another way of explaining is lower on the manifold than the head.It is better to let the smaller intake exit dump into the head unobstructed.Small to large equals velocity anyway.
2. The injector bosses are HUGE! I worked them down with a dremel then shaped them appropiately.They still are going to be hurting max flow.
3.The iron Vortec's turn out nice after port work but the user is still stuck with a 1.5 exhaust valve and really they need screw in studs since the springs must be changed for more of a performance cam,lift wise and RPM.A guy can get a bit of money tied up in Iron Vortechs and still have a relatively light duty head"thin decks".One real good overheat is probably going to crack them. For just a little more cash Edelbrock Etech 200's will out perform them by a long ways.However I do not think the S/D manifold can support the flow the Etechs are capable of.I will post those flow numbers if you wish.
4.From my experience although pleased with the results of this particular application I would have spent my money on a TPIS Bigmouth so I could have run a aluminun or other wise conventional head for the near same money.
5. SD told me that after market runners and a 52mm throttle body gained 1 hp! Can you believe it?The removal of the Mass Air screens gained 15hp.They also told me that the dyno motor was a 350 inch with the hot cam and absolutley no port work to any thing and it made 375hp with 24lb injectors.
I hope this helps some one that might be wanting to do this but did not want to throw down the money until some results came in about the new manifold.
edit to add the Etech 200 flow numbers
int/exh
> 100 67/57
> 200 122/110
> 300 175/153
> 400 223/182
> 500 252/196
> 600 259/204
> 700 265/207
Compare these to the Aluminum GM Fast Burn Heads
[Modified by mountainmotor, 5:22 AM 11/26/2001]
1988 IROC with a 9.5-1 383,700r4 with stock stall and shift kit.2.77 gear w/245/50/16 TA Radials.Maf screen removed and adjustable FPR ,ported plenum.Stock runners.I used 24lb injectors and used the stock but modified cast iron exhaust manifolds" headers will not be considerd on this F Body".A Random Technologies single cat is used.
I port matched the manifold to fully ported iron Vortech heads with screw in studs and a spring upgrade plus I cut the guide bosses down and installed bronze guide liners..I worked the combustion chambers to obtain the 64cc volume that these heads are advertised at to help bring the compression to above specs.When I cc,d them they were 60cc.The cam is a Comp Xtreme Energy Flat Tappet Hydraulic XE 256 H "small base circle"that I had ground on 112 LSA instead of the 110 shelf grind.I degreed it to 5 degrees advanced. I used early style stamped steel 1.5 ratio rockers.I drilled a 0.60 hole in one of the throttle body blades"to get the idle down" and set the timing at 8 degrees but did not use an after market computer chip.
This is my son's car that ran a respectable 14.98 or so at 91-92 mph with 115k on the old 350.It used to burn the tires in first only to bog bad when it hit 2nd gear.Now it lights the tires in first and continues to burn to the top of 2nd.It runs to 5k rpm pretty well.It idles well and is noticeably louder at the muffler.I doubt he will get Street slicks and run it at the track until spring but I am guessing 13,s will not be a problem.We are not going to bother with a chip until this traction problem is cured.I chose this small cam because of the 2.77 gear.I think the next step up XE cam on a 114 lsa would work just as well in hind site but a chip change would probably have been needed.The torque is overkill right now.
All in all it is a fairly decent combo for the price as we were not trying to build it into a street killer however I have seen some draw backs that I will pass along.
1. I would not attempt to completely match the roof of the intake manifold to the heads.The raised roof design of the vortech head and the roof design of the manifold does not make for a good transition if matched completely.It is kind of like a V turned up side down and spread apart.The roof in another way of explaining is lower on the manifold than the head.It is better to let the smaller intake exit dump into the head unobstructed.Small to large equals velocity anyway.
2. The injector bosses are HUGE! I worked them down with a dremel then shaped them appropiately.They still are going to be hurting max flow.
3.The iron Vortec's turn out nice after port work but the user is still stuck with a 1.5 exhaust valve and really they need screw in studs since the springs must be changed for more of a performance cam,lift wise and RPM.A guy can get a bit of money tied up in Iron Vortechs and still have a relatively light duty head"thin decks".One real good overheat is probably going to crack them. For just a little more cash Edelbrock Etech 200's will out perform them by a long ways.However I do not think the S/D manifold can support the flow the Etechs are capable of.I will post those flow numbers if you wish.
4.From my experience although pleased with the results of this particular application I would have spent my money on a TPIS Bigmouth so I could have run a aluminun or other wise conventional head for the near same money.
5. SD told me that after market runners and a 52mm throttle body gained 1 hp! Can you believe it?The removal of the Mass Air screens gained 15hp.They also told me that the dyno motor was a 350 inch with the hot cam and absolutley no port work to any thing and it made 375hp with 24lb injectors.
I hope this helps some one that might be wanting to do this but did not want to throw down the money until some results came in about the new manifold.
edit to add the Etech 200 flow numbers
int/exh
> 100 67/57
> 200 122/110
> 300 175/153
> 400 223/182
> 500 252/196
> 600 259/204
> 700 265/207
Compare these to the Aluminum GM Fast Burn Heads
[Modified by mountainmotor, 5:22 AM 11/26/2001]
