Performer RPM heads...again

We're working on another combo for Dad's Fairmont. Right now it's a 331" SBF, VJ intake, ron's flying toilet alcohol injector...flat top SRP's and RPM #6025 heads (old style). Best ET so far is a 6.85 in the 1/8 at 104 mph. The car is pretty much a stock body Fairmont with the exception of a leaf spring rear suspension with a 9" rear and 28x9 slicks.

We're going with a 353" stroker this time (347" .060" bore), custom pistons, light billet crank & rods, and a different solid roller grind. Compression will be around 14:1 with the pistons and 57cc chambers (the heads have been milled slightly). The engine won't be done for a while, and may not go into the car until next year, but we're sure looking forward to it! We're going to use the RPM heads just as they are....no porting whatsoever. Just milled to take off the material that was damaged during a previous engine failure. Hoping for some 6.50's in the 1/8...what do ya'll think? Do ya think it would achieve that goal? I'd like to see a set of AFR 205's on there...but $$$ is already a problem. The heads would cost more than the short block. Those things are too pricey for no more than they are.

I've only put together one 347....any of ya'll have any pointers or suggestions? I know...the block is the weak point, but it's my father's engine and he has already bought the parts and they're machining the block as we speak...and you simply cannot tell a 66 year old man to do something that he doesn't want to do. It'll run until it blows as he says. Maybe one pass, maybe 100...who knows.
[addsig]

I would consider some bigger heads, Vic JR's, AFR, Canfield, Dart's Z304's........200-215 intake cc Range, they are going to be worth alot of HP on your combo.

Or have your RPM's full CNC'd????
_________________
1991 LX Mustang 347 C4 combo 11's with the AC on.
1984 Mustang GT 460, Powerglide "Still putting it together" hoping for 9's !!
1929 T-Altered "In the works" 8's are on the horizon

<font size=-1>[ This Message was edited by: dfree383 on 5/23/06 11:13pm ]</font>

<font size=-1>[ This Message was edited by: dfree383 on 5/23/06 11:13pm ]</font>

i would just do a little porting on the rpms heads.
[addsig]

I have been 6.58 @104 1.40 60ft with RPMs but I have done some port work on them.

Yep, porting them goes a long way.

14:1 compression. sounds like some real horsepower. i would strongly look into a girdle. we have a 347 in our grand marquis with 13:1 compression and about 500hp. we run 7.20's in the 1/8 at 93-95mph. i use a girdle/windage tray set up from dss, seems to work good.
freshened the motor last year and had no signs of wear on bearings. we have rpm perform with rpm airgap intake, both have been ported and polished and a demon 850 carb.

<font size=-1>[ This Message was edited by: dholroyd on 8/12/06 8:20pm ]</font>

With no porting, and high compression and moderate lift roller cam your intake ports will stall very early...meaning they will go into sonic choke and no matter how big a cam you use it will lay over at higher rpms (like 5500 and up).
Basiclly it would be like building a 408 stroker with stock heads and expecting big HP.
Brian
[addsig]

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On 2006-08-12 05:19, dholroyd wrote:
14:1 compression. sounds like some real horsepower. i would strongly look into a girdle. we have a 347 in our grand marquis with 13:1 compression and about 500hp. we run 7.20's in the 1/8 at 93-95mph. i use a girdle/windage tray set up from dss, seems to work good.
freshened the motor last year and had no signs of wear on bearings. we have rpm perform with rpm airgap intake, both have been ported and polished and a demon 850 carb.

<font size=-1>[ This Message was edited by: dholroyd on 8/12/06 8:20pm ]</font>
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I also have an '84 Mustang coupe...306, KB116's and RPM heads. Nothing fancy at all...VERY VERY mild build. Solid flat tappet camshaft with only a .538" lift, IIRC and 242 duration at .050". IT also runs 7.20's. I love the way this thing runs....pulls really hard up top (like 5000+). Many of the cars I run against in the 7.0 index class also run 7.20's give or take, and it's a total blast to have them pull a fender on me at the 60' and 330, but about 100' before the finish line, I usually drive right by them and take the stripe by a half fender or so. It's like it's turbocharged and the WG allows more boost at 500 feet LOL. I've also been accused of cheating at least once. No cheating here...just got lucky with a thrown together combo, that's all.

I'd love to have a better set of heads on his car, but again $$$ is going to be the set back (as usual). With the 331 in there, it does hit a wall at about 6000, you can literally hear the engine change tone, but it's deadly consistent with the alcohol injection...and we ain't touching it until it grenades. Then maybe the 353" will go in, and if I win the lottery between now & then, he'll have my Vic Jr's on his, and I'll have a set of something else on mine. Probably 225's if I had a choice.
[addsig]

If you're looking to drop some weight off the front end, I have a D&D tubar crossmember and A arms, coilover setup and BBK adjustable plates for your car that's looking for a good home.