john97z28

I am in the process of building a 355 with a D-1SC blower. Initially I was going to build the motor for nitrous and bought the LT4 conversion and had the heads and intake ported and polished. I changed my mind and wanted to do a blower set up and had the LT4 heads re-ported for a supercharger set-up and had larger SV-4 exhaust valves installed. I have about $1500 in labor and after market components on the heads. I plan on purchasing custom JE pistons to get me in the 8.5-9:1 range.

Would I see a significant difference going with TrickFlow heads. I'm trying to see a cost/benefit.

MEAN LT1

Well the trick flows cambers are like 64cc as to the stock Lt4's. I think you'll be better of with some. It wouldnt hurt.......

mn_vette

Ported LT4's should easily outflow the Trickflow heads and if you are only making a 355 you'll have enough room to drop the compression ratio in the pistons. Stick with your LT4's you'll end up with more HP in the end.

engineermike

Yep. The LT4's can be ported to flow some phenomenal numbers. Over 300 cfm in some cases. You'd be hard pressed to get that from any 23 deg head.

Mike

MEAN LT1

I stand corrected.

n2oblkz

Stay with the LT4's, I don't think that the Trick Flow's are getting very good reviews. The LT4's are a good head and will suit your needs just fine. If a lower compression ratio is what you are looking for, you could always go with a larger dished piston to lower it.

john97z28

Thanks for the replies. I feel much better about keeping them now!

blownbird01

the first thing you should do is sell your civic because you look gay driving around in it. sorry I just couldnt resist. be prepared to shovel a few ton of shell this weekend. Saturday morning to be exact. PS I think what you should do is sell me those lt4 heads for about $200.

93redz

hey you may have a civic but atleast you dont drive a FORD ..since you sold me your p1sc i will give you $300 for the Lt4 heads LOL..

jnjspdshop

flow over 300cfm in some rare and expensive cases, however the castings are still very thin for a blower car. If you wanna get extreme with FI, and stick with a regular 23° LTx head I would go with an AFR comp ported 210cc. Various chamber sizes are available, a plus to this is you don't have to run a larger dish piston. Thicker pistons are always better in blower applications

94zgreenmachine

here is the data on the trick flow head. I was interested for a supercharged car but will do that build up later. They will still need some work to get full potential. My stock lt1 castings after Lloyd is done will flow more. Here it is:

Trickflow Specialties LT1 23* Cylinder Head

Specifications
Part Numbers: Assembled: 30400010 Bare: 3042B010

Material: A356-T6 Aluminum.

Intake Port Size: 195cc 2.07”x 1.26” Port Opening. (Stock LT1 port opening)

Exhaust Port Size: 75cc, 1.35” Tall x 1.50” Wide.

Combustion Chambers: 62cc.

Valve Sizes: 2.02” Intake, 4.690” OAL, 11/32” Diameter, .250” Tip TFS #51400211
1.60” Exhaust, 4.980” OAL, 11/32” Diameter, .250” Tip TFS #51400212

Valve Guide Material: Manganese Bronze, .500” OD.

Valvetrain Componentry
Valve Locks: 7* Steel, + .050” Installed Height. TFS #51400444

Valvespring Retainers: 7* Steel, 1.460” Diameter. TFS #51400423

Valvesprings: 1.460” Diameter, Dual Spring. TFS #31400414
125lbs Seat PSI @ 1.780” Installed Height.
375lbs Open PSI @ 1.180” Compressed Height.
420 lbs / inch Spring Rate.
.600” Maximum lift.

Valve Seals: Positive Clamp Viton Rubber. TFS # 51400454

Rocker arm Studs: ARP 3/8” diameter. TFS # 51400613

Pushrod Guide plates: For use with 5/16” diameter hardened pushrods. TFS #30400623-8

Flow Data
Intake Exhaust
.100” 50 57 Exhaust flow testing was done WITHOUT the use of a pipe.
.200” 135 98
.300” 191 136 2.02”/1.60” Valve sizes. All testing was done on an AS CAST
.400” 229 162 head.
.500” 253 176
.600” 254 189 Flow Testing was done at 28” H2O.

Denny McLain

[QUOTE=
Flow Data
Intake Exhaust
.100” 50 57 Exhaust flow testing was done WITHOUT the use of a pipe.
.200” 135 98
.300” 191 136 2.02”/1.60” Valve sizes. All testing was done on an AS CAST
.400” 229 162 head.
.500” 253 176
.600” 254 189 Flow Testing was done at 28” H2O.[/QUOTE]

Here are the flow numbers as cast using a 2.05 valve and flowed by LE:

.100” 62 45
.200” 130 78
.300” 174 120
.400” 228 151
.500” 253 168
.600” 261 177

For some reason Lloyd was having a little problem flowing the exhaust and these numbers are down some from the ones above. That may account for this.The valve job from Trick Flow was average at best and needed to be redone.

These heads have at least as much potential when ported as LT4's and may have better cooling capabilities. I'll post flow numbers after porting.

94zgreenmachine

Don't forget the heads are 64cc from the factory so compression will go down. They claim thicker deck surface so I wonder how much can be milled before problems begin to show up.

94zgreenmachine

oh, and yes you should sell them to me....for cheap

Denny McLain

I had the heads milled by Trick Flow down to 56cc which is about as much as your going to get out of them with the 2.05 valves. I know of an angle milled set that went to 57cc with 2.05's.

Now Trick Flow telling me they are 56cc and sometimes being 56cc..... is another story. Obviously these will be measured to see if it's correct.

In terms of porting potential, I know of one set using 2.05 valves that are flowing 254cfm @ .400 and 300cfm at higher lifts. There is more potential in the heads but this is from a very good (read.. very high dollar porter) and may not be typical of your average porter.

Again..... these heads according to some do have better cooling passages and frankly is the only reason I choose them over AFR's even though the current quality control issues with AFR has me a bit leery of them. Living in Dallas when it's 100 degrees in the summer kinda changes a few things when your running 12.25 to 1 N/A. Cooler is gooder.