need some help please.
Thread Starter
Instructor
Joined: Jun 2013
Posts: 225
Likes: 1
From: hanceville al
need some help please.
OK so I just had a fast sytem installed and had the car dynoed on a dyno com dyno and the numbers were not what I expected. 245hp 340tq. Here are my mods open air box with K/N, 52mm TB, ported plenum, Edelbrock high flow runners and intake manifold, comp cam lift .480/.480 duration 264/274 lobe sep angle 112, adjustable fuel pressure regulator , 24 lb injectors, exotic muscle long tune headers, no cats, x pipe, corsa cat back exhaust, MSD 8.5mm wires, MSD blaster coil, MSD 6al ignition box, new plugs and all new sensors TPS, IAC extra, FAST efi system, TCI constant prssure valve body, 3:54 gears. I know my heads need to go but I thought better numbers than this! Do these numbers sound right for my mods, what heads do I need to go with to keep around 58cc? thanks for all comments and knowledge.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
You need to tell us that your is a 1990. Stock HP at the engine was 245. Assuming the your posting RWHP....so add 15-20% roughly to bring this back to the engine. Might be a little low..but your plenum and heads are your restriction. You probably picked up most of the gain with the headers. The FAST EFI system will not add HP.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
You made those numbers at the wheel?
They're probably low, but the only things on that lengthy list that actually do anything are;
*Cam
*Base
*Runners
*Headers/Exhaust
Those items with a proper tune should have given you, I'd guess, ~40 - 50 hp...the majority of that coming from the cam and exhaust.
They're probably low, but the only things on that lengthy list that actually do anything are;
*Cam
*Base
*Runners
*Headers/Exhaust
Those items with a proper tune should have given you, I'd guess, ~40 - 50 hp...the majority of that coming from the cam and exhaust.
Thread Starter
Instructor
Joined: Jun 2013
Posts: 225
Likes: 1
From: hanceville al
Hey John, thanks for replying. Sorry about that yes it is a 90 speed density. I had the plenum ported but stock heads. Im on the fence between the trick flow 195s and the AFR 195s. From what I researched the AFR flows better but there about 400 bucks more. Im thinking Im goint to keep my current TPI edelbrock set up so I think the trick flow will work just fine.
Thread Starter
Instructor
Joined: Jun 2013
Posts: 225
Likes: 1
From: hanceville al
Hey Tom, yes that was RWHP. I also relize that different dynos will yeild different numbers. Im hoping to pick up 50 or 60 hp with a good set of heads and 1.6 RR with my current set up. Do you feel that is a liberal estimate?
Thread Starter
Instructor
Joined: Jun 2013
Posts: 225
Likes: 1
From: hanceville al
The trick flow 195s have a 62cc cumbustion chamber and the AFR 195s has a 65cc. The stock heads are 58cc will I have to mill those new heads because of a lose of compression or will they be fine to run with my stock pistons? Thanks
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Putting some numbers down.....
Stock is 245 at the engine and your at 245 rear wheels...so 15% would give you 280 at the engine and 20% would give you 291 at the engine.
Going with the conservative 280 number:
you probably picked up 10-15 HP from the headers
maybe 5 from the ported runners plus the intake
that leaves you with the cam giving you 20
IF you go with a head change....and add 1.6 roller rockers you will pick up more...but you will still be restricted by the breathing of the plenum. You need to complete the package with a SuperRam (no longer in production) or a mini-ram to get the flow to the heads.
I am a big fan of the AFR product. They are not cheap....but HP is not cheap.
Stock is 245 at the engine and your at 245 rear wheels...so 15% would give you 280 at the engine and 20% would give you 291 at the engine.
Going with the conservative 280 number:
you probably picked up 10-15 HP from the headers
maybe 5 from the ported runners plus the intake
that leaves you with the cam giving you 20
IF you go with a head change....and add 1.6 roller rockers you will pick up more...but you will still be restricted by the breathing of the plenum. You need to complete the package with a SuperRam (no longer in production) or a mini-ram to get the flow to the heads.
I am a big fan of the AFR product. They are not cheap....but HP is not cheap.
Race Director
Joined: Feb 2002
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From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
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St. Jude Donor '16
Auto or 6 speed? % of loss at rear wheels is a bit different.
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