L98 Ignition systems; General questions
11-09-2001, 02:13 PM
#21
Melting Slicks
Thread Starter
Re: L98 Ignition systems; General questions (Beach Bum)
[QUOTE]89vette,
You need to look at the little things very, very closely.
1) Valve train geometry... are you sure its correct.
Yes
2) Are you absolutely dead positive the fuel pump is not dropping fp at wot..... flooring it in the garage is not going to give you the answer.... you gotta be on the road with a gauge taped to the windshield.
Yes
3) Ohm out your plug wires even though they look great
Need to do this
4) disconnect your knock sensor.... unwanted or un-needed retard will knock a lot of power out
No timing retard as reported by Diacom during dyno runs
5) Are you positive the TB opens all of the way at wot
Yes
6) Are you positive a plenum or manifold gasket didn't slide while assembly, thus blocking the intake port severely.... that'll make a head flowing 280 cfm flow 200 cfm in effect.
Yes. I looked into the holes to make sure everything was lined up.
7) Are you absolutely positive you have the right header gasket installed... on that protrudes into the exhaust port will kill performance.
Good question. I used the Felpro gaskets that came with the TPIS headers. I saw an earlier post where someone discovered that the gaskets supplied by TPIS actually covered part of the exhaust port. Plus the fact that I have AFR heads may possibly be worse becasue of a possible different location of the exhaust port compared to a regular L98 head? I did a search and did not find that old post yet. If you happen to find it please let me know.
8) Any change your tranny is robbing some power... is it healthy.
As far as I know its fine. Its a 6 speed.
Thanks for the input.
Jason
You need to look at the little things very, very closely.
1) Valve train geometry... are you sure its correct.
Yes
2) Are you absolutely dead positive the fuel pump is not dropping fp at wot..... flooring it in the garage is not going to give you the answer.... you gotta be on the road with a gauge taped to the windshield.
Yes
3) Ohm out your plug wires even though they look great
Need to do this
4) disconnect your knock sensor.... unwanted or un-needed retard will knock a lot of power out
No timing retard as reported by Diacom during dyno runs
5) Are you positive the TB opens all of the way at wot
Yes
6) Are you positive a plenum or manifold gasket didn't slide while assembly, thus blocking the intake port severely.... that'll make a head flowing 280 cfm flow 200 cfm in effect.
Yes. I looked into the holes to make sure everything was lined up.
7) Are you absolutely positive you have the right header gasket installed... on that protrudes into the exhaust port will kill performance.
Good question. I used the Felpro gaskets that came with the TPIS headers. I saw an earlier post where someone discovered that the gaskets supplied by TPIS actually covered part of the exhaust port. Plus the fact that I have AFR heads may possibly be worse becasue of a possible different location of the exhaust port compared to a regular L98 head? I did a search and did not find that old post yet. If you happen to find it please let me know.
8) Any change your tranny is robbing some power... is it healthy.
As far as I know its fine. Its a 6 speed.
Thanks for the input.
Jason
